ABSTRACT - 202307-202402 Flashcards

Question

Quinn - 2024 - VETSURG - Adjunctive fixation of the humeral epicondyle in a lateral condylar fracture model - Ex vivo comparison of pins and plates with a novel composite (AdhFix)

Answer 1

Abstract Objective: To compare the biomechanical properties of using a novel composite construct (AdhFix) to an interfragmentary Kirschner wire or a reconstruction plate as adjunctive epicondylar stabilization in simulated lateral unicondylar humeral fractures. Study design: Cadaveric biomechanical assessment. Sample population: Paired humeri harvested from skeletally mature dogs (14-41 kg), nine cadavers per group. Methods: Simulated lateral unicondylar humeral fractures were stabilized with a transcondylar 4.5 mm cortical screw placed in lag fashion. Adjunct fixations consisting of a novel composite incorporating 2.7 mm cortical screws on one side, and either a 2.7 mm reconstruction plate or a 1.6 mm Kirschner wire on the contralateral side, were tested within paired humeri. Repaired humeri were axially loaded to failure and construct stiffness, yield load, and ultimate load were obtained from the load-deformation curves. Results: In pairwise comparison, yield load was significantly higher for AdhFix group compared to the pin group, p = .016. No statistical significance was seen in the comparison between AdhFix group and the plate group, p = .25. Conclusion: Adhfix was mechanically superior to K-wires, and comparable to plate fixation, for adjunctive fixation in a lateral humeral condylar model. Our results support further investigation of the novel composite for adjunct fracture fixation in lateral humeral condylar fractures. Clinical significance: The novel composite tested may be a viable alternative for adjunct fixation of humeral condylar fractures, a technique that circumvents plate contouring.

Answer 2

Abstract Objective: To report perioperative complications and client-perceived outcome following laparoscopic surgical treatment for sliding hiatal hernia (SHH) in dogs. Animals: Client-owned dogs (n = 9). Methods: Medical records were reviewed and perioperative data collected including preoperative diagnostic imaging, operative details, complications, and need for conversion to open celiotomy. A single-incision, multicannulated port was inserted in the subumbilical region followed by placement of an additional 2 or 3 instrument portals. Hiatal plication, esophagopexy, and left-sided gastropexy were performed laparoscopically. Follow-up information was collected with telephone interview with the owners and/or referring veterinarian. A standardized questionnaire was completed by dog owners postoperatively. Results: Intraoperative pneumothorax occurred in 5 of 9 (55.6%) dogs and resulted in conversion to open celiotomy in 2 (22.2%) dogs. In 4 dogs, pneumothorax was suspected to be the result of progressive leakage of capnoperitoneum through the suture bite holes of the esophageal hiatal plication sutures. Hiatal plication was performed using intracorporeal simple interrupted sutures (n = 4) or a simple continuous pattern with barbed suture (4). Esophagopexy was performed using barbed suture in all dogs. Gastropexy was performed using a total laparoscopic technique (n = 4) or laparoscopic-assisted technique (3). Using a standardized questionnaire, dog owners perceived a postoperative improvement in regurgitation after eating and regurgitation after excitement/increased activity. Clinical relevance: Laparoscopic treatment of SHH resulted in owner-perceived improvement in clinical signs. Intraoperative pneumothorax occurred in a high proportion of dogs but did not result in long-term sequelae.

Answer 3

Objective: To describe the use of a barrier membrane in dogs for repair of congenital hard palate defects and closure of oronasal fistulae (ONF) remaining after previous cleft palate (CFP) repair. Animals: 7 client-owned dogs. Methods: The hard palate defect was closed with medially positioned flaps (Von Langenbeck technique) or pedicle flaps (2-flap palatoplasty) and a membrane composed of autologous auricular cartilage from the pinna or allogenous fascia lata underlying the mucoperiosteal flaps. Results: All palate defects were considered to have a high risk of dehiscence based on their type and size and the characteristics of the surrounding tissue. The barrier membrane was used in 5 dogs for repair of congenital hard palate defects and in 2 dogs for closure of ONF remaining after previous CFP repair. Resolution of clinical signs occurred in all cases. Complete success (ie, complete closure of the palate defect and absence of clinical signs) was achieved in 5 dogs (4 with congenital hard palate defects and 1 with an ONF remaining after previous CFP repair). The persistent ONF in 1 dog with functional success (incomplete closure, but no clinical signs) was smaller than prior to surgery. Clinical relevance: Barrier membranes underlying mucoperiosteal flaps may constitute an alternative technique in dogs for repair of congenital hard palate defects and closure of ONF remaining after previous CFP repair.

Answer 4

Objective: To report the rate of surgical site infections (SSIs) after clean-contaminated and dirty gastrointestinal surgery in dogs and cats that did and did not receive incisional infiltration of Nocita and report the bacteria isolated. Animals: Client-owned dogs (n = 211) and cats (78). Methods: Records of dogs and cats that underwent gastrointestinal surgery at the Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania and the University of Florida Small Animal Hospital between July 1, 2020, and April 1, 2023, were reviewed for surgical procedures, presence of preoperative septic peritonitis, use of Nocita, perioperative antibiotics administered, postoperative antibiotic use, SSI development postoperatively, and aerobic bacteria isolated. Results: 7 of 124 (5.6%) dogs that received Nocita and 9 of 87 (10.2%) that did not receive Nocita developed an SSI. No dogs presenting with septic peritonitis and given Nocita (n = 5) developed an SSI. Two of 55 (3.6%) cats that received Nocita and 1 of 23 (4%) that did not receive Nocita developed an SSI. Multidrug-resistant (MDR) Escherichia coli was the most common aerobic bacteria isolated from SSIs (n = 3), and MDR bacteria were isolated commonly from both groups (4). Clinical relevance: Use of Nocita for gastrointestinal surgery in dogs and cats is not associated with higher rates of SSI than published rates of SSI after gastrointestinal surgery. Use of Nocita in dogs with preoperative septic peritonitis is not associated with the development of SSI. MDR bacteria are commonly isolated via culture from both dogs that received Nocita and those that did not.

Answer 5

Objective: To report clinical features and outcomes of cats undergoing either stereotactic radiotherapy (SRT) or surgical excision for the treatment of intracranial meningioma. Animals: 61 client-owned cats. Methods: Medical records were retrospectively reviewed of cats with intracranial meningiomas that were treated with surgical removal and/or SRT between 2005 and 2017. Signalment, clinical signs, duration of clinical signs, diagnostic imaging reports, histopathology reports, treatment protocol, complications, recurrence or progression, and survival time were obtained from the medical record and through follow-up phone calls. Results: Of the 61 patients, 46 had surgery, 14 had SRT, and 1 had surgery followed by SRT for initial treatment. Significantly more cats that underwent surgery had peritreatment complications compared to the SRT group (P < .0001). Cats that received surgery initially had a significantly longer median survival time (MST) of 1,345 days compared to the MST of 339 days for the SRT cats (P = .002). Fourteen (30%) cats in the surgery group and 4 cats in the SRT group (28%) had MRI- or CT-confirmed tumor regrowth or new tumor growth (P = 1.00). Five cases that had SRT for subsequent recurrence had an MST of 700 days (range, 335 to 1,460 days) after the last treatment. Clinical relevance: SRT proved to be a safe, alternative treatment option for feline patients with intracranial meningiomas; however, the survival times with surgery alone were significantly longer. SRT for the treatment of recurrence following initial surgery may show promising results.

Answer 6

Objective: There is limited information on the normal appearance of the cisterna chyli (CC) in cats on CT and MRI. The aim of this retrospective study was to describe the CT and MRI characteristics of the CC in a group of cats without lymphatic system pathology. Sample: A total of 31 CT and 63 MRI images were obtained of client-owned cats between January 2017 and March 2022. Methods: The presence, location, shape, maximum width, MRI-signal intensity, mean attenuation, and contrast enhancement of the CC were recorded from CT and MRI scans. Results: The CC was identified in all the CT scans and in 60 MRI studies. The CC was located level with the cranial mesenteric artery in 56 of 91 cases. It was crescent shaped in 34 of 54 cases. On precontrast CT images, the mean attenuation of the CC was 17 HU, and the mean postcontrast attenuation was 28 HU. On T2-weighted sequences, the CC was isointense to CSF and hyperintense to the muscles, while on T1-weighted images, it was isointense to the muscles. Contrast enhancement was variable in both techniques. Clinical relevance: CT and MRI have the potential for noninvasive evaluation of CC in cats.

Answer 7

Objective: To identify predictive factors for postoperative continence in female Golden Retrievers following cystoscopic-guided laser ablation of intramural ectopic ureters (CLA-EU). Animals: 41 client-owned female entire Golden Retrievers with uni- or bilateral intramural ectopic ureter(s) were retrospectively enrolled. Methods: Patients were diagnosed with ectopic ureters with a combination of ultrasonography and cystoscopy. CLA-EU was performed for all dogs so that each ureteral opening was considered to be in an appropriate position by a single operator. All dogs had short-term follow-up 4 weeks and long-term follow up > 10 weeks after the procedure via telephone, which included urinary continence scoring. Clinical factors and ultrasonographic and cystoscopic findings from initial presentation were evaluated to identify predictive factors for postoperative continence. Results: Short-term urinary continence was achieved in 46.3% of dogs with no additional medical therapies. Presence of historical urinary tract infections prior to CLA-EU (OR, 0.130; 95% CI, 0.020 to 0.621; P = .018) was negatively correlated and ureteral dilatation (OR, 34.260; 95% CI, 1.813 to 2,143; P = .043) was positively correlated with likelihood of urinary continence. Long-term urinary continence was achieved in 63.4% of dogs, and presence of historical urinary tract infections was negatively prognostic (OR, 0.173; 95% CI, 0.023 to 0.856; P = .048). Clinical relevance: Female Golden Retrievers undergoing CLA-EU have similar outcomes to those reported for other mixed-breed cohorts with > 30% of dogs failing to regain urinary continence. Historical urinary tract infections were significantly associated with both short- and long-term urinary continence in our population.

Answer 8

Objective: To report the prevalence of presumed concurrent medial coronoid process fractures in a series of cases of humeral condylar fractures and evaluate factors influencing the presence of a suspected fracture of the medial coronoid process. Animals: 48 dogs and 7 cats, with a total of 57 humeral fractures. Methods: Medical records of dogs and cats diagnosed with a humeral condylar fracture with radiographs were reviewed between October 2013 and March 2022. Species, sex, neutered status, age, weight, and the nature of the trauma were noted. Radiographs were assessed for the configuration of humeral condylar fracture, the presence of a suspected fractured medial coronoid process (MCP), number of MCP fragments, nature of fracture, degree of radioulnar incongruity, soft tissue swelling, and elbow luxation/subluxation. Results: A presumed fracture of the MCP was seen in 26 of 57 cases. Comminution of the condylar fracture was the only parameter that had a positive effect on the presence of a possible fractured MCP. Body weight was significantly associated with size of the suspected fractured MCP. The presence of this fracture was not associated with the type of humeral condylar fracture. The size of the presumed fractured MCP fragment was positively correlated with body weight. Clinical relevance: There was a high prevalence of presumed fractured MCPs in dogs with humeral condylar fractures (almost 50%) and even more so in animals with comminuted fractures. The consequences of suspected fractured MCP associated with humeral condylar fractures and whether dogs and cats would benefit from removal of the fragment remain unknown.

Answer 9

Objectives: Angiosarcomas are rare malignant mesenchymal neoplasms of endothelial cell origin with a predilection to the ventral abdominal wall in cats. Larger case series describing this entity are lacking. Methods: Two referral centre laboratory databases were searched for angiosarcoma of the ventral abdominal wall. Nine cases with a histological diagnosis were included. Immunohistochemistry (factor VIII and PROX-1 antibodies) was used to phenotype them as haemangiosarcoma or lymphangiosarcoma. Results: All cats presented with a ventral abdominal mass, five of which were producing a serosanguinous discharge. Eight underwent tumour staging and pulmonary metastases were suspected in one cat (but not histologically confirmed). With histopathology alone, a diagnosis of angiosarcoma and lymphangiosarcoma was made in four and five cases, respectively. After immunohistochemistry, five cases had a haemangiosarcoma phenotype and four had a lymphangiosarcoma phenotype, including two cases of lymphangiosarcoma that were reclassified as hemangiosarcoma. Eight cats received treatment (either surgery with or without adjuvant therapies or medical management alone). Six cats were euthanased due to local disease progression. The median survival time for haemangiosarcoma was 166 days (range 137-381), and for lymphangiosarcoma it was 197 days (range 67-208). Two cats with haemangiosarcoma remained alive for a follow-up period of 329 and 580 days, respectively. Conclusions and relevance: Feline ventral abdominal angiosarcomas are rare locally aggressive neoplasms. While histology often provides a diagnosis of angiosarcoma, immunohistochemistry is ultimately required to differentiate between haemangiosarcoma and lymphangiosarcoma phenotypes. Further studies are required to evaluate whether the different phenotypes have an impact on treatment response and outcome.

Answer 10

Objective: The purpose of this study was to evaluate a sit to stand test with the walk test for the identification of unilateral cranial cruciate ligament rupture in dogs. Materials and methods: Peak vertical force and vertical impulse were measured on a pressure-sensitive walkway, during a sit to stand test and walk test, and in 10 dogs with unilateral cranial cruciate ligament rupture and 18 non-lame dogs. Data collected were used to calculate symmetry indices (SI) of ipsilateral and contralateral hindlimbs (HL), diagonal limb pairs (DLP) and ipsilateral limb pairs (ILP). Results: The symmetry indices of peak vertical force of HL during the walk test and sit to stand test were 100% and 90% sensitive for discriminating lame and non-lame dogs respectively. The symmetry indices of vertical impulse of HLs during the walk test and sit to stand test were 100% and 50% sensitive for discriminating lame and non-lame dogs respectively. Analysis of ipsilateral and diagonal limb pairs did not improve the discrimination in either test. The time taken to collect data from the sit to stand test data was shorter than for the walk test. Clinical significance: Whilst the sit to stand test required a shorter time for collection of data than the walk test, it did not accurately identify all dogs with lameness associated with CCLR, and thus has relatively limited clinical utility in its tested form.

Answer 11

Osteoarthritis is a progressive degenerative disease process that affects a significant proportion of the canine population, impacting these animals' quality of life. Currently, there is no cure and treatment consists of managing the clinical signs of pain and reduced mobility. There are many treatments for canine osteoarthritis and in this review we discuss the evidence base behind non-pharmaceutical, non-surgical treatments of this disease. These treatments include weight management, nutraceuticals, acupuncture, physiotherapies such as therapeutic exercise, hydrotherapy as well as other therapeutic modalities including photobiomodulation therapy, electromagnetic field therapy and others.

Answer 12

Objectives: The purpose of this study was to determine changes in urolith trends and factors associated with different urolith types in dogs from the Republic of Ireland and Northern Ireland between 2010 and 2020. Materials and methods: A laboratory database was searched for canine urolith submissions between 2010 and 2020. Trends in urolith composition between 2014 and 2020, and associations between patient characteristics with each urolith type were evaluated. Results: A total of 1162 submissions were included. Struvite (39.0%), calcium oxalate (27.8%) and compound (10.2%) were the most prevalent uroliths. Calcium oxalate urolith (CaOx) incidence significantly increased from 27.8% to 31.2% and that of struvite significantly decreased from 41.7% to 33.0% between 2014 and 2020. Struvite uroliths were overrepresented among females compared to males (odds ratio 8.7, 95% confidence interval 6.6 to 11.5). Males (odds ratio 9.6, 95% confidence interval 6.9 to 13.3) and dogs >7 years of age (odds ratio 4.1, 95%, confidence interval 3.0 to 5.4) were more likely to have CaOx while males (odds ratio 9.6, 95% confidence interval 5.3 to 17.8) and dogs ≤7 year of age, purine uroliths (odds ratio 3.0, 95% confidence interval 1.8 to 5.0). Incidence was higher in bichon frise (odds ratio 1.7, 95% confidence interval 1.3 to 2.4) and Yorkshire terrier (odds ratio 2.8, 95% confidence interval 1.9 to 4.1) for CaOx and higher in shih-tzu for compound uroliths (odds ratio 1.7, 95% confidence interval 1.1 to 2.7) compared to the remaining reported breeds. Clinical significance: Factors associated with different uroliths were similar to the ones previously reported. Proportion of CaOx submissions increased and that of struvite decreased over the study period which was in agreement with the changes identified in other European countries.

Answer 13

Objectives: To describe the clinical presentation, treatment and outcomes of cats diagnosed with thymic epithelial tumours and to determine prognostic factors for survival and recurrence. Materials and methods: Clinical records of cats diagnosed with a thymic epithelial tumour between 1999 and 2021 at three referral institutions were retrospectively reviewed. Results: Sixty-four cats were included. Paraneoplastic syndromes were present in nine cats and metastatic disease was seen in two cats, one at diagnosis and one at the time of recurrence. Median tumour diameter was 6 cm (range, 2 to 15) and a cystic appearance was described on imaging in 25 cats. Surgical excision was attempted in 54 cats with a perioperative mortality rate of 11%. Median survival time for cats surviving to hospital discharge was 897 days (range, 21 to 3322). The 1-, 2- and 5-year survival rates for surgically treated thymic epithelial tumour were 86%, 70% and 66%, respectively. Survival was longer for cats with Masaoka-Koga stage I and II tumours compared to stages III and IV (1366 days versus 454 days; P=0.002). Masaoka-Koga stage was the only significant prognostic factor detected on multi-variable analysis, with stage III and IV tumours associated with increased risk of death (hazard ratio: 5.67, 95% confidence interval: 1.29 to 24.91, P=.021). Tumour recurrence occurred in 11 cats at a median of 564 days (range, 93 to 1095); no significant prognostic factors for recurrence were identified. Clinical significance: Cats with thymic epithelial tumours had a good long-term prognosis following surgery. Tumour recurrence can occur late in the disease course and ongoing monitoring should therefore be considered. Masaoka-Koga stage may influence survival time and could be used to predict outcome.

Answer 14

Objectives: To characterise head tilt as a rare clinical sign of cervical spinal or paraspinal disease in dogs. Materials and methods: Retrospective single-centre case-series study of dogs with head tilt and cervical spinal or paraspinal disease in the absence of intracranial abnormalities. Descriptive statistics were used. Results: Fifteen dogs met the inclusion criteria of this study. Median age at onset was 6 years (range 2.5 to 12 years). Onset of neurological signs was mainly chronic (9/15, 60%). Most common presenting complaints included head tilt (9/15, 60%) and cervical hyperaesthesia (8/15, 53%). Most common neurological findings included head tilt (15/15, 100%), generalised proprioceptive ataxia and tetraparesis (6/15, 40%) and cervical hyperaesthesia (8/15, 53%). Diagnoses included post-operative complication of C2 spinal nerve root mass removal (2/15, 13%), C3-C4 intervertebral disc extrusion (2/15, 13%), cervical paraspinal myositis (2/15, 13%) and one of each: C2 vertebral malformation, C2 spinal nerve root mass, C1-C2 meningioma, C2 vertebral fracture, C4-C5 intervertebral disc extrusion, C4 vertebral body mass, C5-C7 osseous-associated cervical spondylomyelopathy, and concurrent C5-C6 and C6-C7 intervertebral disc protrusions. Two dogs were euthanased shortly after diagnosis and two of 15 were dogs lost to follow-up. No post-mortem examination was performed for these cases. For the 11 of 15 remaining dogs, head tilt resolved in eight of 15 (53%) dogs after treatment of the underlying condition and in three of 15 (20%) dogs, it remained static. Clinical significance: Head tilt can be a rare clinical sign of cervical spinal or paraspinal disease in dogs.

Answer 15

Objective: The aim of this study was to evaluate the feasibility of safe positioning of double 2.3-mm headless cannulated self-compression screws (HCS) in a small dog cadaveric sacroiliac luxation model and to compare the static rotational biomechanical properties of fixation repaired using two different screw systems with a minimally invasive osteosynthesis technique: double 2.3-mm HCS and a single 3.5-mm standard cortical screw placed in a lag fashion. Study design: A unilateral small dog sacroiliac luxation model was stabilized using double 2.3-mm HCS (n = 11) or a single 3.5-mm cortical screw (n = 11). Radiographic and computed tomography (CT) imaging analyses and biomechanical testing of rotational force on the sacroiliac joint of both fixations were performed. The maximum load at failure and failure modes of each fixation were recorded and compared. Results: Fluoroscopically guided percutaneous application of double HCS was safe in a unilateral sacroiliac luxation model in small dogs without violation of the vertebral and ventral sacral foramen. Furthermore, resistance to rotational force applied on fixation of the sacroiliac joint repaired with double 2.3-mm HCS estimated by maximum failure load was significantly higher than that of a single 3.5-mm cortical screw (p < 0.001). Conclusion: Although this was an experimental cadaveric study, based on our results, the use of smaller double HCS may be beneficial as an alternative to the conventional single lag screw for stabilization of sacroiliac luxation in small dogs.

Answer 16

Objective: The aim of this study was to determine the effect of plate-bone distance (PBD) and working length on 2.0-mm locking compression plate (LCP) stiffness and strain in four-point bending and torsion in a diaphyseal fracture gap model. Study design: A total of 54 LCP with three screws per fragment were assigned to one of nine combinations of working length (WL; short, medium, and long), and PBD (1, 1.5, and 3 mm) for a sample size of six per construct configuration. Stiffness was measured under quasistatic, nondestructive four-point compression bending and torsion. Plate surface strain was recorded using three-dimensional (3D) digital image correlation during four-point compression bending. Results: WL had a significant effect on overall construct stiffness in both compression bending and in torsion, with shorter WL constructs having higher stiffness (p < 0.0001). PBD had no effect on construct stiffness in compression bending; however, a significant reduction in stiffness was noted in torsion (p = 0.047) as PBD incrementally increased. WL had a significant effect on plate strain in compression bending, with shorter WL constructs having lower plate strain (p < 0.0001). PBD had no effect on plate strain in compression bending except for lower plate strain recorded in long WL constructs with 1-mm PBD, compared with 1.5- and 3-mm PBD constructs (p < 0.0001). Conclusion: Longer WL constructs, regardless of PBD, had lower stiffness in compression bending, while in torsion, some modulation of this effect was noted with incremental decreases in PBD. Longer WL resulted in high plate strain, regardless of PBD.

Answer 17

Objective: The aim of this study was to determine the prevalence of contralateral cranial cruciate ligament rupture (CCLR) in dogs 8 years of age or older, weighing more than or equal to 15 kg at the time of first-side CCLR and to assess associated risks. Study design: It is a cross-sectional retrospective study of 831 client-owned dogs METHODS: Medical records of dogs weighing more than or equal to 15 kgs that were more than or equal to 8 years of age at the time of first CCLR diagnosis were reviewed. Data collected included weight, sex, pre-operative tibial plateau angle, co-morbidities, time between diagnosis of first CCLR and diagnosis of contralateral CCLR. Multivariate logistic regression analysis was used to estimate odds ratio. A median follow-up period of over 112.7 months (25th/75th quartiles 75.4/157.7 months) from first CCLR diagnosis was allotted. Results: Eight-hundred thirty-one dogs were identified and included. About 19.1% (159/831 dogs, 95% confidence interval: 16.6-22.0%) of dogs that experience a first-side CCLR at 8 years of age or older will rupture the contralateral side, a median of 12.9 months (25th/75th quartiles 6.5/24.3 months) later. Age (p = 0.003) and breed, Golden Retrievers (p = 0.028) and Labrador Retrievers (p = 0.007), were factors significantly associated with contralateral CCLR. Clinical relevance: The prevalence of contralateral CCLR in medium-to-large breed dogs more than or equal to 8 years of age old is less than previously reported and the risk decreases as they age. This important information will help guide owners when deciding to pursue surgical stifle stabilization following CCLR in older dogs.

Answer 18

Objective: The aim of this study is to describe the use of String of Pearls (SOP) plates for the surgical management of feline pelvic fractures, including surgical technique, proposed indications, complications, and outcomes in a cohort of cats. Study design: This study is a single-center retrospective clinical case series. Methods: Medical records (2015-2019) of cats presenting for pelvic fractures (n = 33) were reviewed. Type of fracture, preoperative and postoperative imaging, and complications were retrospectively retrieved. Owners were contacted via questionnaire for medium- and long-term follow-up. Results: A total of 20 cats met the inclusion criteria. Minor intraoperative complications were encountered in three patients. One patient suffered a major intraoperative complication. Five major complications were encountered postoperatively. These included two greater trochanter osteotomy fixation implant removal and three SOP plate removal. Full function was recovered in all patients according to the owners' assessment. Clinical significance: The use of SOP plates in feline pelvic fractures appears to yield a consistently good outcome with a very low incidence of canal narrowing and screw loosening. SOP plates are easy to contour and to apply along the entire pelvic length.

Answer 19

Objectives: This study aims to report complications and long-term outcomes of combined tibial plateau leveling osteotomy and tibial tuberosity transposition (TPLO-TTT) for treatment of concurrent cranial cruciate ligament rupture and medial patellar luxation (MPL). Study design: This is a retrospective study. Dogs that underwent TPLO-TTT for treatment of combined cranial cruciate ligament rupture and grade III or IV MPL were included. Signalment, fixation method, and complications were recorded. Long-term outcome assessment (minimum 1 year postoperatively) was performed through clinical and radiographic reexamination at the authors' institution. Results: Twenty-four stifles (22 dogs) were included. Twenty-one stifles had a grade III MPL, and 3 stifles had grade IV MPL. Four major complications consisting of surgical site infection (n = 3) and recurrent grade II MPL (n = 1) were observed. Dogs with surgical site infections were successfully treated with implant removal and oral antibiotics. No additional surgery was performed for the patient with recurrent MPL as no signs of lameness were observed. Minor complications occurred in five cases. At long-term evaluation (median: 27 months; range: 12-67 months), 21/22 dogs were clinically sound and 23/24 stifles had a complete resolution of MPL. Conclusion: TPLO-TTT can be considered as an effective surgical option to treat patients with concurrent cranial cruciate ligament rupture and MPL with a relatively low major complication rate. Owners should be warned of the potential need for implant removal.

Answer 20

Objective: Canine hip dysplasia is a common orthopaedic disease in dogs. The Norberg angle value is a measure of hip joint laxity. The aim of this study was to quantify the degree of rotation necessary to consider the radiograph as inadequately positioned and to determine the influence of rotation on the Norberg angle. Study design: Three sets of radiographs with different positioning and projections were acquired using 10 canine cadavers. Rotation of the pelvis was simulated by rotating the X-ray tube without changing the position of the patient. Results: In dorsoventral projections, the Norberg angle value is increased by 3.2 to 5.8%. Due to rotation along the long axis, the Norberg angle increases on one side and decreases on the contralateral side by approximately the same value. Rotation of greater than 2 degrees in a lateral direction is visually perceived by the observer as tilted. Rotation of the projection in the caudoventral to craniodorsal direction causes mild increase of the Norberg angle (≤1%), while rotation of the projection in a cranioventral to caudodorsal direction causes moderate (≤2%) decrease of the Norberg angle. Rotation of less than -10 degrees (caudoventral to craniodorsal) or greater than 10 degrees (cranioventral to caudodorsal) is visually perceived as tilted. Conclusion: Tilted images that are subjectively perceived evaluable have only little effect on the Norberg angle and are therefore probably acceptable. Dorsoventral projections can be recognized based on the proximal position of the patella and should be excluded from evaluation, as the Norberg angle value can be falsely increased.

Answer 21

Objective: While it has been known for a long time that laxity in the hip joint is the primary cause of degenerative changes later on in canine hip dysplasia, limited data are available on the fundamental characteristics that define the procedure used to quantify this. The aim of this study was to evaluate the force-laxity relation to assess the repeatability of repeated cycles of stress on the hip joint and determine the force necessary tomeasure a sufficient proportion of laxity present in hip joints. Materials and methods: Thirty-four canine cadavers underwent a radiographic protocol including stress radiographs with increasing force using the Vezzoni modified Badertscher distension measuring device (VMBDmD). Three dogs underwent five repeat examinations. The laxity index (LI) and osteoarthritis were scored. Results and conclusion: The curves and the maximal LI (LImax) were not significantly influenced by osteoarthritis, weight, gender, and side. The position of the VMBDmD influenced the curve but not the LImax. The force-laxity curve itself and the LImax were repeatable, which indicated that it did not cause permanent damage to the joint and also confirmed the practicability of the procedure. Ninety percent of hip joints reached sufficient laxity at a force of 95.32 N, which is realistically achievable. Further studies are necessary before extrapolating these results to patients and to further enlighten the biomechanics of stress radiographs.

Answer 22

Objective: The aim of this study was to define the extent of the biceps tendon, subscapularis tendon, and cranial border of the medial glenohumeral ligament within the field of view during standard lateral shoulder arthroscopy in the dog. We also examine the effect of joint flexion on the field of view of the biceps tendon. Study design: This was a cadaveric study using 21 shoulders of large breed dogs. Each shoulder was explored with a 30-degree arthroscope using standard lateral ports. For each supporting structure, the margins within the arthroscopic field of view were marked with ink. In 11 shoulders, the distal margin of the biceps tendon was identified and marked first with the limb at a standing angle and then in flexion. The margins of the cranial border of the medial glenohumeral ligament were marked at the standing angle. In 10 additional shoulders, the margins of the subscapularis tendon were evaluated. Each joint was fully dissected and the portion of each stabilizing structure within the field of view was quantified. Results: Fifty-eight percent of the cranial border of the medial glenohumeral ligament was within the arthroscopic view. At a standing angle, 48% of the intra-articular length of the biceps tendon was within the arthroscopic view, compared to 63% with the limb flexed. Twenty percent of the subscapularis tendon was within the arthroscopic view. Conclusion: A significant portion of the biceps tendon and medial stabilizing structures of the canine shoulder are outside the field of view of arthroscopy through a standard lateral approach. The limitations of the arthroscopic field of view should be appreciated when evaluating the shoulder.

Answer 23

Objective: To compare the prevalence of pre-, intra-, and postoperative variables and complications associated with staphylectomy (S) and folded flap palatoplasty (FFP). Study design: Retrospective study. Sample population: Client-owned dogs (n = 124). Methods: Medical records of S and FFP dogs from a veterinary teaching hospital were reviewed between July 2012 and December 2019. Signalment, clinical pre-, intra-, and postoperative data were collected and reviewed. Median (interquartile range) was reported. Results: A total of 124 dogs among 14 breeds underwent surgical treatment for an elongated soft palate with either a S (n = 64) or FFP (60). FFP dogs without concurrent non-airway procedures were associated with longer duration of surgery (p = .02; n = 63; S, median = 51 min [34-85]; FFP, median = 75 min [56.25-94.5]) and anesthesia (p = .02; n = 63; S, median = 80 min [66-125]; FFP, median = 111 min [91-140.8]). Neither soft palate surgery was associated with the occurrence of anesthetic complications (p = .30; 99/120; S, 49; FFP, 50), postoperative regurgitation (p = .18; 27/124; S, 17; FFP, 10), or with hospitalization duration (p = .94; n = 124; S, median = 1 day [1]; FFP, median = 1 [1]). Postoperative aspiration pneumonia (9/124; S, 4; FFP, 5) and major complications were rare (5/124; S, 3; FFP, 2). Conclusion: S and FFP had similar anesthetic and perioperative complications, although FFP dogs had longer anesthetic and operative times. Clinical significance: Although FFP took longer, no other clinically significant differences were appreciated between S and FFP procedures. Because of limitations inherent in study design, surgeons should continue to use clinical judgment when deciding on a procedure.

Answer 24

Objective: To determine morphologic differences between four tibial osteotomy techniques used to correct excessive tibial plateau angle (eTPA). Study design: Retrospective radiographic analysis. Sample population: Sixteen dogs (27 tibias) with eTPA. Methods: Virtual corrections of eTPA were performed on sagittal plane radiographs of canine tibia using four tibial osteotomy techniques and categorized into respective groups. Group A represented the center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) and coplanar cranial closing wedge ostectomy (CCWO), Group B the tibial plateau leveling osteotomy (TPLO) and CCWO, Group C the modified CCWO (mCCWO), and Group D the proximal tibial neutral wedge osteotomy (PTNWO). Pre- and post-correction TPA, tibial length and mechanical cranial distal tibial angle (mCrDTA) were measured and compared. Results: Mean TPA prior to correction was 42.67 ± 6.1°. Post-correction mean TPAs were 10.47 ± 2.1°, 6.77 ± 1.6°, 4.76 ± 1.5°, and 7.09 ± 1.3° for Groups A, B, C, and D, respectively. TPA correction accuracy in Groups A and D varied least from target TPAs. Tibial shortening was documented in Group B in contrast to other groups. The greatest mechanical axis shift was identified in Group A. Conclusion: Each technique achieved TPA < 14° despite having different effects on tibial morphology including alteration of tibial length, mechanical axis shift and variation in correctional accuracy. Clinical significance: Despite all methods being able to correct eTPA, the choice of technique will affect morphology in unique ways and should be considered prior to surgery to consider the implications in a given patient.

Answer 25

Objective: To determine the influence of preclosure antiseptic versus saline lavage on surgical site infections (SSI) in dogs following tibial plateau leveling osteotomy (TPLO). Study design: A multicenter retrospective study. Sample population: Dogs treated with TPLO (n = 1422) between December 2019 and October 2021. Methods: The medical records of dogs treated with TPLO were reviewed for preclosure antiseptic lavage or saline irrigation. Additional collected data included signalment, unilateral or bilateral TPLO, postoperative administration of antimicrobial medications, antibiotic agent, surgeon, and development of SSI within 90 postoperative days. Eleven factors were analyzed for association with SSI using univariate and multivariate analysis. Results: Data were collected from the records of 519 dogs treated with antiseptic lavage and 903 dogs treated with saline lavage during TPLO. Surgical site infections were diagnosed more frequently in dogs that received preclosure antiseptic lavage (77/519, 14.84%) than those with saline irrigation (80/903, 8.86%) (p = .001). Single session bilateral TPLO increased the odds of SSI by 2.5x (p = .004). The odds of SSI increased by 11% (p = .001) for every 5 kg increase in bodyweight. Postoperative administration of antimicrobials decreased the risk of SSI (p = .008). Conclusion: The preclosure antiseptic lavage tested here did not decrease the incidence of SSI after TPLO. Clinical significance: The results of this study do not provide evidence to support preclosure antiseptic lavage during TPLOs.

Answer 26

Objective: (1) To determine whether Oxley's modified cranial closing wedge osteotomy (CCWO) results in a tibial plateau angle (TPA) of 5° in silico, (2) compare in silico to clinical postoperative TPA and (3) determine the impact of ostectomy distalization in silico. Study design: Cross-sectional retrospective radiographic in silico study. Sample population: A total of 100 stifle radiographs; 90 dogs (small ≤25 kg = 84; large >25 kg = 16). Methods: Tibial plateau angles were measured preoperatively (TPAPre ), after in silico planning (TPAPlan ), and postoperatively (TPAPost ). Virtual ostectomies were evaluated for plate fit. Postoperative ostectomy position was measured. Virtual ostectomies were performed 5/7.5/10/15 mm from the patellar tendon insertion in 10 dogs from each preoperative TPA category (≤20°/21-25°/ 26-30°/31-35°/>35°). Comparisons for TPAPre , TPAPost , and TPAPlan were made between small and large dogs, and the outcome to the target 5° between TPA categories and ostectomy positions. Results: Mean ± SD TPAPre was 28.6 ± 6.2° and higher in small than large dogs. Mean TPAPlan was 7.6 ± 2.7°. Plate fit was appropriate in all. In silico, TPAs were greater than 5° except for cases with TPAPre > 35°. Median TPAPost was 5.5° (-4-21) and was higher in small (7°) than large (4.5°) dogs. Postoperative ostectomy position was more distal than Oxley's guidelines. When distalized >7.5 mm in silico, the magnitude of under-correction increased. Conclusions: Oxley's modified CCWO did not result in TPA of 5° in most cases. Ostectomy distalization exacerbated under-correction. Clinical impact: Current guidelines should be modified to achieve 5° TPA postoperatively.

Answer 27

Objective: To compare intra- and interobserver agreements in two-dimensional measurements of changes in nasopharyngeal dimensions during breathing in pugs and French bulldogs. Study design: Experimental randomized study. Animals: A total of 20 French bulldogs and 16 pugs. Methods: Four observers with different levels of experience measured the dorsoventral dimensions of the nasopharynx during inspiration and expiration on fluoroscopy videos. Measurements were performed at the maximal narrowing of the nasopharynx for the functional method and at the level of the tip of the epiglottis for the anatomically adjusted method. The intra- and interobserver agreements of the measurements, ratio of the dynamic nasopharyngeal change (ΔL), and grade of nasopharyngeal (NP) collapse (no, partial or complete) were evaluated. Results: The functional method resulted in intraobserver correlation coefficients of 0.532 (p < .01) and 0.751 (p < .01) and interobserver correlation coefficients of 0.378 (p < .01) and 0.621 (p < .01) for NP collapse grade and ΔL, respectively. The anatomically adjusted method, 0.491 (p < .01) and 0.576 (p < .01) and 0.495 (p < .01) and 0.729 (p < .01) for NP collapse grade and ΔL, respectively, were being used. One observer (radiologist) achieved intraobserver correlation coefficients >0.9 for both methods. Conclusion: Fair interobserver agreement was found for NP collapse grade (functional method), moderate intra- and interobserver agreements were found for NP collapse grade and ΔL (both methods) while intraobserver agreement for ΔL was good (functional method). Clinical significance: Both methods seem repeatable and reproducible but only for experienced radiologists. The use of ΔL may offer higher repeatability and reproducibility than grade of NP collapse regardless of the method used.

Answer 28

Objective: To assess diagnostic value and clinical utility of multidetector computed tomographic positive contrast arthrography (CTA) for meniscal lesions in dogs. Study design: Prospective case series. Study population: Client-owned dogs (n = 55) with cranial cruciate ligament injuries. Methods: Sedated dogs underwent CTA using a 16-slice scanner, and subsequently received mini-medial arthrotomy for meniscal assessment. Scans were anonymized, randomized, and reviewed twice for meniscal lesions by three independent observers with varying experience. Results were compared with surgical findings. Reproducibility and repeatability were assessed with kappa statistics, intraobserver changes in diagnosis by McNemar's test, and interobserver differences using Cochran's Q test. Test performance was calculated using sensitivity, specificity, proportion correctly identified, and positive and negative predictive values and likelihood ratios. Results: Analysis was based on 52 scans from 44 dogs. Sensitivity for identifying meniscal lesions was 0.62-1.00 and specificity was 0.70-0.96. Intraobserver agreement was 0.50-0.78, and interobserver agreement was 0.47-0.83. There was a significant change between readings one and two for the least experienced observers (p < .05). The sum of sensitivity and specificity exceeded 1.5 for both readings and all observers. Conclusion: Diagnostic performance was suitable for identifying meniscal lesions. An effect of experience and learning was seen in this study.

Answer 29

Objective: To investigate how tibial long axis (TLA) shift affects the postoperative tibial plateau angle (TPA) in four cranial closing wedge ostectomy (CCWO) techniques. Study design: In silico study. Sample population: A total of 15 client-owned dogs. Methods: Computed tomography (CT) scans of 15 client-owned dogs were reviewed using an open-source 3D computer graphics editor. Each computer-generated 3D tibia model underwent a CCWO, with cranial cortex alignment, in 10° increments up to 70° using each of the four previously described techniques. The TLA shift, TPA and mechanical tibial length (mTL) were calculated, using trigonometry, for each model. Equations for predicting final TPA were generated with linear regression. Results: A total of 433 3D computer generated tibial models were analyzed. With each technique, the TPA varied in a linear fashion within the studied range of wedge angles. The TLA shift and tibial shortening magnitude varied between the four different CCWO techniques, with maximum mTL reduction of ranging from 7.5% to 40.9%. All predicted TPAs using the generated equations were within the target range of 4-6°. Conclusion: A linear relationship between ostectomy wedge angle and TPA correction was observed in this study, which allowed for generation of accurate corrective equations. Clinical significance: These results allow extrapolation of the wedge angle required to reach a postoperative TPA of 5°, by considering the TLA shift. The use of the generated corrective equations may thus increase CCWO planning precision.

Answer 30

Abstract Objective: To report sensitivity, specificity, predictive values and accuracy of a client questionnaire at diagnosing surgical site infections (SSIs) and describe the impact of active surveillance on SSI detection. Study design: Prospective, cohort study. Animals: Dogs and cats undergoing soft tissue or orthopedic surgery over a 12-month period at a referral hospital. Methods: Clients were emailed a questionnaire 30 days postoperatively, or 90 days where an implant was used. Three algorithms were developed to diagnose SSIs using one or both of two criteria: (1) presence of any wound healing problems; (2) wound dehiscence or antibiotic prescription, and either purulent discharge or two or more clinical signs (redness, pain, heat, swelling, discharge). Algorithmic diagnoses were compared to gold standard diagnoses made by veterinarians. Results: Of 754 surgical procedures, 309 responses were completed with 173 corresponding gold standard diagnoses. The most accurate algorithm determined "SSI" or "No SSI" from 90.2% of responses with 95.5% (92.4-98.6) accuracy, 82.6% (77-88.3) sensitivity, 97.7% (95.5-100) specificity, 86.4% (81.2-91.5) positive predictive value, and 97% (94.5-99.6) negative predictive value. "No SSI" was diagnosed in responses not meeting criterion 1, and "SSI" in responses meeting criteria 1 and 2. "Inconclusive" responses, comprising 9.8% of responses, met criterion 1 but not 2. Overall SSI rate was 62/754 (8.2%) and 12/62 (19.4%) SSIs were detected by active surveillance only. Conclusion: Use of this client questionnaire accurately diagnosed SSIs; active surveillance increased SSI detection. Clinical significance: Surveillance of SSIs should be active and can be simplified by using a client questionnaire and algorithmic diagnoses, allowing automated distribution, data collection and analysis.

Answer 31

Objective: To compare the effects of three different rhinoplasty techniques on the postoperative cross-sectional areas (CSAs) of the nares and nasal vestibuli. Study design: Experimental study. Sample population: Ninety-nine 3D-printed, remolded silicone models of a single French bulldog's rostral nose. Methods: Models were fabricated based on a computed tomographic (CT) scan of the nose of a French bulldog with moderately stenotic nares. Each model underwent either vertical wedge resection (VW), modified horizontal wedge resection (MHW), or ala-vestibuloplasty (AVP) performed by a single surgeon (n = 33 per group). Preoperative and postoperative CT scans of the models were performed, and CSAs of the airway from the nares to the caudal end of the nasal vestibules were calculated. Results: All three rhinoplasty techniques increased CSAs (adjusted p values <.001) but to different levels caudally within the nasal vestibule. Vertical wedge resection achieved this up to the start of the alar fold, MHW up to halfway between the nares and the alar fold and AVP up to the caudal nasal vestibule. Average percentage increases in CSA were 26%, 15% and 74%, respectively. Ala-vestibuloplasty led to larger CSAs than VW and MHW from the nares to the caudal nasal vestibule (adjusted p values <.05). The proportional difference within each technique was <7%. Conclusion: Ala-vestibuloplasty resulted in a larger increase in the airway CSA of silicone modeled nares and nasal vestibules of a single French bulldog in comparison with VW and MHW. Clinical significance: Ala-vestibuloplasty can be considered for French bulldogs with moderately stenotic nares and evidence of nasal vestibular stenosis.

Answer 32

Objective: To determine the effect of indocyanine green (ICG) dose and timing of administration on near-infrared fluorescence (NIRF) imaging of the normal canine biliary tree. Study design: Preclinical prospective study. Animals: Eight purpose-bred beagles. Methods: The dogs were randomized to receive two of four intravenous ICG dose (low [L]:0.05 mg/kg or high [H]:0.25 mg/kg)/time (0 and 3 h prior to NIRF) combinations. NIRF images were collected every 10 min for 120 min. Target (cystic duct)-to-background (liver) ratios were calculated for all timepoints and compared. Results: ICG cholangiography was successful in all dogs. The contrast ratio was above 1 in the L0 group by 20 min and reached its peak at 100 min. In the H0 group, the ratio was above 1 by 60 min and reached its peak at 90 min. Contrast ratios above 2 (fluorescence twice as bright in the cystic duct compared to the liver) were maintained from 180 to 300 min for L3 and H3 and was achieved after 80 min for L0. Conclusion: Low dose ICG provided better ratios early after injection compared to the high dose which remained highly concentrated in the liver tissue after injection. Both doses provided excellent visualization of the biliary tree at 3 h post injection, low dose ICG provided better ratios from 3 to 5 h post injection. Based on these results, 0.05 mg/kg of ICG administered at anesthetic premedication, or as early as 3 h prior to laparoscopic surgery should yield optimal fluorescence images. Clinical significance: This study provides guidelines for NIRF cholangiography in clinically normal dogs.

Answer 33

Objective: To assess the use of adrenaline (0.00198%) in a bilateral maxillary nerve block to reduce intraoperative hemorrhage in dogs undergoing staphylectomy for the treatment of brachycephalic obstructive airway syndrome (BOAS). Study design: Prospective, randomized, double-blinded controlled study. Sample population: A total of 32 client owned, clinically affected dogs undergoing a cut and sew sharp staphylectomy for treatment of BOAS. A total of 16 dogs randomly assigned to adrenaline (A) group and 16 to no-adrenaline (NA) group. Methods: A bilateral maxillary nerve block was performed in all dogs prior to staphylectomy using lidocaine alone (group NA) or a combination of lidocaine and adrenaline (group A). Total hemorrhage was measured by weighing cotton-tipped applicators and swabs used on precision scales. In addition, a semi-quantitative hemorrhage score (1-5) was determined. Dogs were monitored for intraoperative hemodynamic stability during the procedure. Results: Total hemorrhage was significantly (p = .013) lower in group A compared with group NA. The median semi-quantitative hemorrhage score was significantly lower for group A (p = .029) compared with group NA. No significant adverse effects were noted due to adrenaline usage. Conclusion: This study demonstrated that the use of adrenaline in a bilateral maxillary nerve block results in significantly lower intraoperative hemorrhage during cut and sew sharp staphylectomy and appeared safe to use. Clinical significance: Potential clinical advantages include improved visualization, prevention of unnecessary blood loss and reduction in risk of blood aspiration.

Answer 34

Objective: To compare mortality of dogs undergoing partial staphylectomy using conventional incisional, carbon dioxide (CO2 ) laser, and bipolar vessel sealing device (BVSD) techniques for the treatment of brachycephalic obstructive airway syndrome (BOAS). Study design: Retrospective multicenter cohort study. Animals: A total of 606 client-owned English bulldogs, French bulldogs, and pugs. Methods: Medical records from 2011 to 2021 were reviewed for signalment, history, surgical technique, length of hospitalization, and complications. Multivariate statistical analysis was performed to compare odds of mortality between the three techniques of staphylectomy. Results: The overall mortality rate was 24/606 (4.0%). Of those 24 dogs, staphylectomy was performed with BVSD technique in 13 cases, with CO2 laser in nine, and using conventional incisional technique in two. Nine dogs were graded II or III laryngeal collapse, 14 were graded I, and one was unknown. BVSD technique was associated with mortality prior to discharge compared to the other two techniques (OR = 6.0, 95% CI: 1.3-28.4, p = .023). No differences were detected between conventional incisional and CO2 laser techniques. Concurrent higher grade (stage II or III) laryngeal collapse was independently associated with mortality prior to discharge (OR = 4.6, 95% CI: 1.8-11.8, p = .002). Conclusion: The use of BVSD and grade of laryngeal collapse were associated with a higher risk of perioperative mortality. Clinical significance: Clinical studies using a randomized trial design should be conducted to further determine the putative influence of surgical instrumentation in the perioperative mortality rate following multilevel surgery in dogs with BOAS.

Answer 35

Objective: To establish parameters that describe acidic gastroesophageal reflux (GER) events in nonbrachycephalic, hospitalized dogs without gastrointestinal disease following short total intravenous anesthesia, to establish upper reference limits for parameters that describe GER. Study design: Clinical prospective study. Animals: Healthy, client-owned dogs presenting for elective orthopedic surgery. Methods: Dogs were sedated with IM methadone (0.2 mg/kg) and medetomidine (5 ug/kg), followed by alfaxalone total intravenous anesthesia. The Digitrapper esophageal dual pH monitoring probe was placed transnasally into the esophagus. Dogs were unsedated during the subsequent recording period. A GER event was defined as esophageal pH less than 4.0. Parameters that described GER were: (1) number of GER events per hour, and (2) cumulative esophageal acid exposure (percentage of recording duration) at each sensor. Upper reference limits were calculated for each parameter. Results: Thirty-five dogs were included (median age 7 years, range 1-12). The median recording duration was 21.1 h (range 13.6-29.3). Productive regurgitation was not noted in any dog. The median number of distal and proximal GER events per hour was 0.3 (range 0-4.3) and 0 (range 0-1), respectively. The median cumulative distal and proximal esophageal acid exposure was 0.2% (range 0.3-9%) and 0% (range 0%-1%), respectively. Conclusion: Upper reference limits for distal and proximal GER per hour was 2.4 and 0.4, respectively, and, for cumulative distal and proximal esophageal acid exposure, 2.3% and 0%, respectively. Clinical significance: Dogs undergoing esophageal pH monitoring in a similar hospital setting with parameters above these upper reference limits have excessive GER.

Answer 36

A 4-year-old French bulldog was presented with neck pain and left forelimb lameness. CT scan revealed a bony defect in the craniodorsal rim of the endplate of C5 with a concomitant disc protrusion leading to ventral spinal cord compression. Ventral slot at C4-C5 was performed to remove the protruding material and the fragment. Based on CT and histological findings, this bone defect was consistent with osteochondritis dissecans. Neck pain was absent immediately after the operation and the dog recovered without complication. Only a slight proprioceptive deficit of the left forelimb persisted during the 6-month of follow-up. Based on our search of the veterinary literature, this is the first published report of an osteochondritis dissecans of cervical endplate treated surgically.

Answer 37

Abstract Objective: To identify risk factors for intra- and postoperative ventricular arrhythmias (VAs) and in-hospital mortality in dogs undergoing splenectomy for splenic masses. Animals: 308 dogs. Methods: Records from 2010 through 2018 were reviewed for dogs undergoing splenectomy for a splenic mass. Clinical and laboratory findings on admission, diagnostic imaging, anesthesia, surgery and pathology reports, treatment records, and in-hospital mortality were evaluated with logistic regression. Results: VAs occurred in 138 (44.8%) dogs (126/308 [40.9%] postoperative, 51/308 [16.6%] intraoperative, 26/308 [8.4%] preoperative), with 50/308 (16.2%) dogs having more than one type of VA. Increasing heart rate and body weight, decreasing PCV and platelet count, hemoperitoneum, receipt of a transfusion, and diagnosis of hemangiosarcoma were associated with the presence of intra- and postoperative VAs on univariable analysis (all P < .001). On multivariable analysis, hemoperitoneum (P < .001 , < .001), increasing body weight (P = .026, < .001), and increasing heart rate (P = .028, < .001) were significant for intra- and postoperative VAs, respectively. Twenty dogs died (20/308 [6.5%]; 14/138 [10.1%] with VAs, 6/170 [3.5%] without VAs). Intra- and postoperative VAs were associated with in-hospital mortality (P = .009, .025, respectively). Clinical relevance: Perioperative VAs were common and odds of VAs were increased with hemoperitoneum, increasing heart rate, and increasing body weight. Presence of VAs increased the odds of in-hospital mortality. Despite this, the overall in-hospital mortality rate was low (6.5%), indicating a good prognosis for survival of surgery in dogs with splenic masses, regardless of the presence of VAs or hemoperitoneum.

Answer 38

Objective: To investigate the incidence and patterns of gunshot wound trauma in patients that were presented to an urban level 1 veterinary trauma center before and after the start of the coronavirus disease of 2019 (COVID-19) pandemic. Animals: 24 dogs and 1 cat. Methods: Medical records were retrospectively reviewed for patients presenting with gunshot wound injuries between March 2018 and February 2020 (prepandemic) and March 2020 and February 2022 (pandemic). The total number of patients presented to the hospital during those same time periods was also obtained. Patient data were collected including species, breed, age, sex, location of injury, trauma score (if available), surgical procedures performed, length of hospitalization, and case outcome. Results: In the prepandemic period, 9 patients were presented for gunshot wound injuries, whereas there were 16 patients evaluated for gunshot wound injuries during the pandemic period. The total number of gunshot wound cases increased by 77.8% in the pandemic period. The total number of hospital patient visits, however, decreased by 12.2% in the pandemic period as compared to the prepandemic period: 65,168 versus 74,262 patients, respectively. Injuries were predominantly localized to the extremities (55%) in the prepandemic period versus maxillofacial (56%) in the pandemic period. Clinical relevance: There was an increased number of gunshot wound injuries in companion animals presenting to an urban level 1 veterinary trauma center during the COVID-19 pandemic. A shift in the predominant location of injury was also identified during the pandemic period. This study highlights the ramifications that societal dynamics can have on animal health and welfare.

Answer 39

Objective: To describe the clinical presentation, diagnostic imaging findings, surgical technique, histopathological diagnosis, and postoperative outcome in 3 cats with extensive vaginal masses. Animals: Medical records of cats diagnosed with vaginal masses that had a bilateral pubic and ischial osteotomy and vaginectomy between 2004 and 2022 were retrospectively reviewed. Three cats met the inclusion criteria. Clinical presentation: Histopathological diagnosis included T-cell-rich B-cell lymphoma (n = 1), mycetoma (1), and vaginal polyp (1). Diagnostic imaging included CT (n = 2) and MRI (1), and tumor length/width/height percentages in relation to the pelvic dimensions were 53% X 62% X 63% (case 1), 50% X 100% X 60% (case 2), and 150% X 120% X 120% (case 3). A bilateral pubic and ischial osteotomy was performed in all 3 cases. Results: All 3 cases developed mild pelvic-limb splaying postoperatively; all resolved within 8 weeks, and 2 cases fully resolved within 14 days. Two of the 3 cases presented with mild stranguria postoperatively, which resolved fully in both cases. Clinical relevance: Vaginal neoplasia, either malignant or benign, is infrequently reported in cats in the veterinary literature. Bilateral pubic and ischial osteotomy for resection of vaginal masses in cats is a successful surgical approach, offering good exposure for resection of large vaginal masses, with minimal postoperative complications.

Answer 40

Objective: To conduct a retrospective multi-institutional study reporting short- and long-term outcomes of adrenalectomy in patients presenting with acute hemorrhage secondary to spontaneous adrenal rupture. Animals: 59 dogs and 3 cats. Methods: Medical records of dogs and cats undergoing adrenalectomy between 2000 and 2021 for ruptured adrenal masses were reviewed. Data collected included clinical presentation, preoperative diagnostics, surgical report, anesthesia and hospitalization findings, histopathology, adjuvant treatments, and long-term outcome (recurrence, metastasis, and survival). Results: Median time from hospital admission to surgery was 3 days, with 34% of surgeries being performed emergently (within 1 day of presentation). Need for intraoperative blood transfusion was significantly associated with emergent surgery and presence of active intraoperative hemorrhage. The short-term (≤ 14 days) complication and mortality rates were 42% and 21%, respectively. Negative prognostic factors for short-term survival included emergent surgery, intraoperative hypotension, and performing additional surgical procedures. Diagnoses included adrenocortical neoplasia (malignant [41%], benign [12%], and undetermined [5%]), pheochromocytoma (38%), a single case of adrenal fibrosis and hemorrhage (2%), and a single case of hemangiosarcoma (2%). Local recurrence and metastasis of adrenocortical carcinoma were confirmed in 1 and 3 cases, respectively. Overall median survival time was 574 days and 900 days when short-term mortality was censored. No significant relationship was found between histopathological diagnosis and survival. Clinical relevance: Adrenalectomy for ruptured adrenal gland masses was associated with similar short- and long-term outcomes as compared with previously reported nonruptured cases. If hemodynamic stability can be achieved, delaying surgery and limiting additional procedures appear indicated to optimize short-term survival.

Answer 41

Objective: To investigate the use of a locking 3.5/4.0-mm jumbo tibial plateau leveling osteotomy (TPLO) plate in maintaining the postoperative tibial plateau angle (TPA) in giant-breed dogs weighing > 50 kg and to report the associated complications. Animals: Canine patients weighing > 50 kg that underwent TPLO stabilized with a locking 3.5/4.0-mm jumbo TPLO plate between January 2017 and May 2022. Methods: Retrospective case series retrieving postoperative outcomes from the medical records. Healing scores and TPAs were calculated using postoperative and recheck radiographs. Owner-perceived outcomes were obtained via questionnaire. Results: 24 stifles in 22 dogs were included. Postoperative complications were recorded in 11 of 24 cases (45.8%) inclusive of 1 minor, 1 catastrophic, and 9 major complications. A statistically significant increase in TPA over the convalescent period was found. Grade 4 healing was present in 18 of 24 (75%) stifles, while the remainder were scored as grade 3. Clinical relevance: The use of a locking 3.5/4.0-mm jumbo TPLO plate did not prevent a statistically significant increase in TPA through convalescence. This procedure displayed an unacceptably high complication rate when compared with contemporary literature of TPLO. Despite a high complication rate in this patient population, most complications were successfully managed with medical and/or surgical treatment, and high mean and median healing scores were achieved at the radiographic recheck. Additionally, owner-perceived long-term outcomes were excellent.

Answer 42

Objective: To report the short- and long-term outcomes of laparoscopic adrenalectomy (LA) for resection of unilateral adrenal masses and to document risk factors for conversion and peri- and postoperative morbidity. Animals: 255 client-owned dogs. Methods: Dogs were included if LA was attempted for resection of a unilateral adrenal mass. Medical records were evaluated and relevant data were reported, including complications, conversion, perioperative death, and long-term outcomes. Signalment, clinicopathological data, and surgical experience were factors statistically evaluated for possible associations with capsular penetration during surgery, conversion, surgical time, duration of hospital stay, death prior to discharge, mass recurrence, and survival time. Results: 155 dogs had left-sided tumors, and 100 had right-sided tumors. Conversion to an open approach was performed in 9.4% of cases. Capsular penetration (19.2%) and major hemorrhage (5.4%) were the most prevalent intraoperative complications. Of the dogs operated on, 94.9% were discharged from the hospital. Lesion side, portion of the gland affected, and surgeon experience influenced surgical time. Conversion rate increased with increasing body condition score and lesion size. Risk of death prior to discharge increased with increasing lesion size. Risk of conversion and death prior to discharge were lower when performed by more experienced surgeons. Capsular penetration during LA increased the risk of tumor recurrence. Clinical relevance: LA for resection of unilateral adrenal masses is associated with excellent outcomes in experienced centers. Surgeons with greater experience with LA have lower surgical times, conversion rates, and risk of death prior to discharge.

Answer 43

Objective: To identify prognostic indicators and inflammatory markers associated with nonsurvival in dogs with gallbladder mucoceles (GBMs) following cholecystectomy and to evaluate C-reactive protein (CRP) and haptoglobin concentrations in dogs with GBMs compared to healthy controls. Animals: 25 dogs that underwent cholecystectomy for removal of GBM and 20 healthy control dogs. Methods: A prospective, multicenter cohort study. Survival outcomes to hospital discharge and 2 weeks postdischarge were recorded from medical records. Laboratory variables, inflammatory markers (CRP and haptoglobin), and 25-hydroxyvitamin(OH) D (25[OH]D) concentrations were measured preoperatively. Associations between signalment, clinicopathologic variables, acute patient physiologic and laboratory evaluation (APPLEFAST) scores, inflammatory markers, 25(OH)D concentration, and survival were analyzed using logistic regression. Results: 76% (19/25) and 68% (17/25) of dogs survived to hospital discharge and 2 weeks postdischarge, respectively. For each additional year of age, the odds of nonsurvival in hospital and 2 weeks postdischarge increased by 2.2 (P = .01; 95% CI, 1.2 to 5.0) and 1.7 (P = .04; 95% CI, 1.0 to 3.2), respectively. Intraoperative systolic blood pressure ≤ 65 mm Hg increased the probability of nonsurvival in hospital (P < .04). Gallbladder perforation, APPLEFAST scores, and preoperative serum concentrations of CRP, haptoglobin, and 25(OH)D were not associated with survival. Serum CRP and haptoglobin concentrations were greater in dogs with GBM compared to controls (P < .001). Clinical relevance: Increasing age and intraoperative systolic blood pressure ≤ 65 mm Hg were associated with nonsurvival in dogs with GBM undergoing cholecystectomy. Serum CRP, haptoglobin, and 25(OH)D were not associated with nonsurvival postcholecystectomy in this sample population.

Answer 44

Objective: To describe the application and owner experience of tube cystostomy for management of upper motor neuron urinary bladder dysfunction secondary to intervertebral disk extrusion (IVDE) or ischemic myelopathy, and to report complications associated with cystostomy tube management. Animals: 61 dogs. Clinical presentation: Medical records of dogs with IVDE or ischemic myelopathy cranial to the L3 spinal cord segment that underwent tube cystostomy placement via a short, caudal ventral midline celiotomy were reviewed. Days from tube placement to hospital discharge, days from placement to tube removal, and complications were recorded. An owner questionnaire was distributed to ascertain ease of use and perceived time commitment. Results: 58 dogs were diagnosed with IVDE, and 3 dogs were diagnosed with ischemic myelopathy. The modal neurologic grade at cystostomy tube placement was 4 (range, 3 to 5). The median number of days from cystostomy tube placement to hospital discharge was 1 (range, 0 to 3). Follow-up data was available for 56 dogs. The median number of days from cystostomy tube placement until removal was 19 (range, 3 to 74). Fifteen minor and 6 severe postoperative complications were reported, mainly inadvertent removal (n = 11) and peristomal urine leakage (6). Twenty-seven owners responded to the questionnaire and primarily reported that cystostomy tube use was easy (22/27) and perceived time commitment was low or minimal (20/27). Clinical relevance: Tube cystostomy facilitates early hospital discharge and allows at-home, extended urinary management in dogs recovering from upper motor neuron urinary bladder dysfunction secondary to IVDE or ischemic myelopathy. This technique is simple for owners to use.

Answer 45

Objectives: The objectives of this study were to investigate the c.1024G>T SNP in the TRPV4 gene in Scottish Straight and Fold cats, and to evaluate the pattern of skeletal phenotype and the evolution of radiological signs of Scottish Fold osteochondrodysplasia (SFOCD) over time in heterozygous subjects. Methods: DNA was obtained from blood samples of 17 cats (Scottish Fold: n = 12; Scottish Straight: n = 5) and subsequently genotyped by sequencing in a 249 bp region of the TRPV4 gene (exon 6), including the known c.1024G>T causative mutation for osteochondrodysplasia. Orthopaedic and radiographic analyses were performed on animals carrying the mutant allele. Results: Genotyping by sequencing confirmed that all and only the Scottish Fold cats carried the mutant allele in a heterozygous asset. Furthermore, two other exon variants, already described in the literature as silent variants, were found in some of the sampled cats. Comparative orthogonal radiographic views of the shoulder, elbow, carpus, hip, stifle and tarsus were obtained. A mediolateral projection of the thoracic and lumbar column was also performed. Three out of four cats were clinically and radiographically examined again 1.5 years later. Conclusions and relevance: Although the presence of the mutant allele in all the tested Scottish Fold cats was confirmed, only 1/12 showed clinical signs of SFOCD. Furthermore, no cats in the 1.5-year follow-up showed skeletal changes. Although significant, the c.1024G>T mutation in the TRPV4 gene, supposedly, is not the only cause or risk of developing SFOCD.

Answer 46

Objective: To report and evaluate the risk factors for complications following bi-oblique proximal ulnar osteotomy (PUO) in dogs. Animals: 82 client-owned dogs (93 limbs). Methods: Clinical records of dogs treated with bi-oblique PUO over a 5-year period were reviewed. Postoperative radiographs were analyzed, and osteotomy location and angles were recorded; follow-up radiographs were reviewed to assess the degree of osteotomy healing. Complications were classified as minor, major, and catastrophic. Logistic regression analysis was performed to investigate possible associations between the predictor variables and occurrence of complications. Results: 82 dogs (93 limbs) were included. Postoperative complications were documented in 39 limbs (13 major and 26 minor). The most common major complication was osteotomy nonunion (8 limbs), while the most common minor complication was delayed union (21 limbs). Statistical analysis revealed that lower body weight (P = .01) and older age (P = .04) were significantly associated with the development of postoperative complications. Clinical relevance: In this study, lighter and older dogs were more likely to develop complications following bi-oblique proximal ulnar osteotomy. We did not identify an association between osteotomy angle and location on complication rate. Careful patient selection is therefore required to reduce the incidence of postoperative complications after bi-oblique PUO.

Answer 47

Objective: To report the short-term and long-term outcomes of dogs that underwent the modified closed and traditional closed anal sacculectomy procedures for the treatment of anal sac neoplasia. Animals: 90 client-owned dogs. Methods: The medical records of 2 tertiary referral hospitals were reviewed to identify dogs that underwent anal sacculectomy for treatment of anal sac neoplasia between January 2016 and December 2020. Data collected included signalment and preoperative diagnostic findings. The occurrence of intraoperative and postoperative complications, short-term outcomes, and long-term outcomes were also collected. Descriptive statistics were calculated to summarize dog signalment information, and recurrence, metastasis, and survival proportions were compared between techniques using Fisher exact tests. Results: 35 and 55 dogs, respectively, underwent the modified or traditional closed anal sacculectomy procedure. Minor postoperative complications that resolved with minimal intervention occurred in 5 of 35 (14.3%) modified approach dogs and 12 of 55 (21.8%) traditional approach dogs. Tumor recurrence was confirmed in 8 of 35 (22.9%) modified and 8 of 55 (26.4%) traditional approach dogs and was suspected in 3 of 35 (8.6%) and 6 of 55 (13.2%; P = .68), respectively. Confirmed metastatic disease was identified in 8 of 35 (22.9%) and 14 of 53 (26.4%) modified and traditional approach dogs, respectively, and was suspected in 4 of 35 (11.4%) and 7 of 53 (13.2%). Sixty-three (70%) dogs survived to study conclusion. Clinical relevance: No benefits in complication rate or local recurrence were identified in dogs following the modified approach as opposed to the traditional closed anal sacculectomy technique.

Answer 48

Objective: Cranial cruciate ligament disease (CCLD) is the most prevalent orthopedic problem in canines, affecting 3% to 5% of dogs, causing stifle instability, mobility dysfunction, and pain. The objective of this study was to evaluate the American Kennel Club field trial community's knowledge of CCLD and estimate its perceived prevalence within this population. Sample: 401 field trial participants responded, with 701 field trial canines reported. Methods: A survey instrument was emailed to a population of Retriever field trial participants to collect information on perceptions and experience with CCLD and current canine participants. Analyses included descriptive statistics, multiple logistic regression, and χ2 tests (significant at P < .05). Results: The majority of respondents appropriately identified the connection between genetics and CCLD (69%). There was under-recognition (6%) of the degenerative nature of the disease, with 61% inappropriately identifying trauma as the major cause. Respondents also indicated that a CCLD diagnosis in a dog's sibling or offspring affected their breeding decisions less than a diagnosis in their parents, indicating a misunderstanding of genetics. More than half of respondents indicated prior experiences with CCLD. The reported occurrence of CCLD was found to be 12% (72/610) in field trial Labrador Retrievers. Clinical relevance: There is a lack of knowledge in the field trial community regarding CCLD. This population showed a higher owner-perceived occurrence of CCLD compared to data collected from medical records. Further investigation is warranted to validate the true prevalence of CCLD in field trial Retrievers.

Answer 49

Objective: Pancreatitis resulting in extrahepatic biliary obstruction (EHBO) can cause substantial morbidity and mortality. Endoscopic retrograde cholangiopancreatography is utilized for diagnostic and therapeutic purposes in humans; however, this is not available in veterinary medicine. Treatment options include medical management and biliary drainage procedures. The aim of this study was to describe the management of EHBO secondary to pancreatitis in dogs, treated medically and surgically and to determine whether the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) differ between the treatment groups. Animals: 41 dogs treated for EHBO secondary to pancreatitis during the period of May 2015 to November 2021. Methods: Records from 41 dogs diagnosed with EHBO secondary to pancreatitis were reviewed, and information extracted included clinical signs, ultrasound findings, NLR, PLR, histopathology, treatment, and outcomes. Results: 18 of 19 (95%) surgical patients survived, while 12 of 21 (57%) medical patients survived. There was no difference in the length of hospitalization or time to return to adequate function between the groups; however, there was a significant difference in the 2- and 12-month survival between those treated surgically and medically. There was no difference in the NLR or PLR between surgically versus medically treated dogs or between survivors and nonsurvivors. Clinical relevance: The mortality rate of surgery for EHBO secondary to pancreatitis may be lower than previously described, and in this cohort of dogs, those treated surgically had improved survival at 2 and 12 months compared to those treated medically.

Answer 50

Objective: To evaluate the effect of variable centrifugation protocols on the cellular composition of the final product of a canine autologous conditioned plasma double-syringe system. Animals: 30 client-owned healthy adult medium- to large-breed (17- to 45-kg) dogs. Methods: 35 mL of anticoagulated whole blood from each subject was aliquoted into 3 samples: a baseline and 2 double syringes. The syringes were processed for platelet-rich plasma (PRP). Each double syringe was randomly assigned to 1 of 5 groups, which varied in centrifugation settings between 580 and 1,304 X g and 5 and 10 minutes. CBC analysis was performed on each of the samples to determine cellular composition. A mixed-effect linear model was fit to the data. Results: 60 PRP samples and 30 whole blood samples were analyzed. Manufacturer settings generated a platelet fold change > 1 but did not increase concentration to the extent expected. When comparing speed alone, increased centrifugation force was associated with lower platelet fold change. When comparing time alone, increased centrifugation time was also associated with lower platelet fold change and lower leukocyte concentration. Clinical relevance: Autologous conditioned plasma double syringes require a low volume of initial whole blood, making them preferable for canine PRP in clinical settings. This study aimed to evaluate the effect of the centrifugation protocol on the final product cellular composition in dogs and add to the available data on protocols to maximize platelet yield in PRP. Due to inherent individual variability, this study emphasized the importance of evaluating biological samples prior to administration to predict and improve patient outcomes.

Answer 51

Objective: To determine the prevalence of splenic malignancy in cats undergoing splenectomy and to investigate possible factors associated with post-operative outcome. Animals: 62 client-owned cats that underwent splenectomy. Methods: Medical records of 4 UK-based referral hospitals were searched and data reviewed retrospectively over 17 years. Factors associated with outcomes post-splenectomy were analyzed. Results: 50 out of 62 cats (81%) were diagnosed with splenic neoplasia. Mast cell tumor ([MCT], 42%), hemangiosarcoma ([HSA], 40%), lymphoma and histiocytic sarcoma (6% each) were the most common tumor types. Fifteen cats (24%) presented with spontaneous hemoabdomen and were all diagnosed with splenic neoplasia. The diagnostic accuracy of cytology to detect splenic malignant lesions was 73% (100% for MCTs and 54% for mesenchymal tumors). Median survival time for cats with nonneoplastic splenic lesions was 715 days (IQR, 18 to 1,368) and 136 days for cats with splenic neoplasia (IQR, 35 to 348); median survival time was longer for cats with splenic MCT when compared to cats with HSA (348 vs 94 days; P < .001). Presence of metastatic disease and anemia (PCV < 24%) at diagnosis were associated with a poorer survival when considering all cats. Presence of anemia, a splenic mass on imaging or spontaneous hemoabdomen were associated with a diagnosis of HSA (P < .001). Clinical relevance: Benign splenic lesions were uncommon in this cohort of cats. Spontaneous hemoabdomen should prompt the clinician to suspect neoplasia in cats with splenic disease. Anemia and evidence of metastasis at diagnosis were poor prognostic factors regardless of the final diagnosis.

Answer 52

Objective: To compare the effect of a geometric, landmark-guided lymphadenectomy (LL) approach to peripheral lymph nodes (LNs) on successful LN identification, surgical time, tissue trauma, and ease of LN identification compared to standard lymphadenectomy (SL) and methylene blue-guided lymphadenectomy (MBL). Sample: 18 adult, mixed-breed canine cadavers operated on by 7 veterinarians and 5 fourth-year veterinary students between July 23 and October 12, 2022. Methods: Participants were provided standardized, publicly available materials regarding the anatomy and surgical techniques for SL of 3 peripheral lymphocentrums: superficial cervical, axillary (ALN), and superficial inguinal (SILN). Participants performed the 3 SLs unilaterally on canine cadavers. Thereafter, they were randomly assigned to 2 crossover groups: MBL and LL. All dissections were separated by at least 2 weeks for each participant. Primary outcome measures included successful LN identification, surgical time, tissue trauma scores, and subjective difficulty. Results: Successful LN identification was highest with LL (86%) compared to SL (69%) and MBL (67%). Subjective difficulty scores were reduced with LL for SILN dissections. Tissue trauma scores were reduced when using LL for ALN and SILN compared to MBL and SL. Time to LN identification was reduced for ALN with LL. No significant differences were observed between MBL and SL, or for the superficial cervical dissections. Clinical relevance: Peripheral lymphadenectomies are time consuming and difficult for veterinarians in early stages of surgical training. Little surgical guidance is provided within current literature. Geometric, landmark-guided lymphadenectomies may improve LN identification success and reduce surgical time, tissue trauma, and procedure difficulty, which could encourage their clinical application.

Answer 53

Objective: To describe the dome trochleoplasty procedure and report the short-term outcomes and complications associated with a novel technique to correct patellar luxation and patella alta. Animals: 13 dogs (16 stifle joints) diagnosed with medial patellar luxation with concurrent patella alta in dogs > 20 kg. Clinical presentation: Medical records of dogs weighing > 20 kg that underwent a dome trochleoplasty for correction of a medial luxating patella were prospectively evaluated. The procedure described involves an osteotomy of the femoral trochlea, which is then translated and/or rotated to correct patellar luxation. Clinical results were assessed using subjective lameness scoring, radiographic evaluation, and the Canine Brief Pain Inventory (CBPI) tool. Results: 16 stifle joints were included in this study. The overall complication rate was 50%. Major complications occurred in 43.8% of stifle joints due to pin migration and recurrent luxation of the patella. One dog experienced a catastrophic complication 4 months postoperatively. Uncomplicated osteotomy healing was present in 94% of dogs. The median initial lameness score was 2 (mean, 1.81; range, 0 to 4) and at the final recheck was 0 (mean, 0.31; range, 0 to 2). The CBPI scores were available for 50% of stifle joints. The median initial CBPI score was 45.5 (mean, 48.8; range, 32 to 74) and at the final recheck was 17.5 (mean, 20.5; range, 0 to 43). Clinical relevance: The dome trochleoplasty procedure offers an alternative technique for surgical correction of patellar luxation secondary to patella alta in large-breed dogs, but due to its higher complication and reluxation rates, it should be used cautiously and probably in combination with other corrective procedures, such as tibial tuberosity transposition, soft tissue imbrication, and/or soft tissue release rather than as a stand-alone procedure.

Answer 54

Objective: To describe radiotherapy outcomes for canine infiltrative lipomas and provide detailed radiotherapy planning data. Animals: 24 dogs from 2000 to 2020. Methods: In this retrospective study, dogs received 1 to 3 surgeries prior to conventionally fractionated radiotherapy for gross (18) or microscopic (8) infiltrative lipomas. Dogs received 45 to 51 Gray (Gy) in 15 to 20 daily fractions, with 71% of dogs receiving 48 Gy in daily 3-Gy fractions. Results: Masses were regionally located as follows: limbs (7), trunk (13), head/neck (4). At analysis, 16/24 dogs were deceased, 5/24 were alive (median follow-up for alive dogs: 1,216 days [range, 741 to 1,870 days]), and 3/24 were lost to follow-up. One living dog had progressive disease 923 days after completing conventionally fractionated radiotherapy and received another surgery. The estimated median overall survival (OS) after completing radiotherapy was 4.8 years (1,760 days; 95% CI, 1,215 to 2,777 days; range, 23 to 3,499 days) for any cause of death, and no patients were reported to have been euthanized or died from their tumor. No statistically significant difference was found for dogs based on gross versus microscopic disease (gross OS, 4.8 years vs microscopic OS, 3.6 years; P = .45). Furthermore, the number of surgeries before radiotherapy did not impact survival (P = .96). The survival difference between females (median OS, 7.6 years; 95% CI, 963 days to not reached) versus males (median OS, 4.6 years; 95% CI, 335 to 2,245 days; P = .05) was statistically significant, although 4/5 living dogs were female. Clinical relevance: This study demonstrates lengthy survivals with radiotherapy, even with gross disease, for dogs with infiltrative lipomas.

Answer 55

Practical relevance: Diseases of the hepatobiliary system are not uncommon in first-opinion practice. The anatomy of the feline hepatobiliary tract differs from that of dogs and may predispose cats to inflammatory hepatobiliary disease. Case management can be challenging, and the prognosis is variable and dependent on the underlying disease process. Clinical challenges: Biliary tract disease in the cat has non-specific clinical signs that overlap with those of diseases of other body systems. Diagnostic tests of the hepatobiliary system are widely available, but interpretation of results can be challenging. Deciding on medical or surgical management can also be challenging; for example, various degrees of cholestasis may be seen with different diseases and disease severities, and will influence the decision to manage the patient medically or surgically. Surgery is indicated in cases of bile peritonitis, severe cholestasis, focal neoplasia or disease that is refractory to medical management. Intensive perioperative and postoperative management, with 24 h hospitalisation facilities, is essential. Audience: This review article is written for the small animal general/primary care practitioner, with an emphasis on decision-making in the surgical management of feline hepatobiliary disease. Evidence base: Evidence available in the published literature is reviewed and presented, and the inherent limitations are discussed.

Answer 56

Objectives: To investigate short-term outcome and complications following the use of the cranial superficial epigastric axial pattern flap to reconstruct cutaneous defects in dogs. Materials and methods: Medical records from dogs undergoing reconstructive surgery between 2008 and 2022 by means of cranial superficial epigastric axial pattern flap were reviewed. Data on signalment, reason for reconstruction, defect size, flap healing, post-operative complications and need for revision surgery were collected. Results: Six dogs were included in the study. Indications for reconstruction included neoplasia (4/6), skin necrosis due to vehicular trauma (1/6) and dog bite (1/6). Postoperative complications occurred in 50% of the patients and included seroma (1/6), bruising (2/6) and necrosis of the distal portion of the flap (2/6), with two dogs developing concurrent complications. One dog required open wound management and additional surgery. Overall outcome was scored excellent in three, good in two, and fair in one dog. Clinical significance: Despite the relatively high complication rate, most of the complications were deemed minor and could be managed conservatively. Eventually, all wounds healed completely and only one flap required revision surgery.

Answer 57

Objectives: This study aims to describe a perioperative protocol for dogs recovered from anaesthesia with the owners and discharged from the hospital on the same day after surgical management of brachycephalic obstructive airway syndrome and to determine whether implementation of this protocol was associated with reduced incidence of complications compared with standard anaesthesia recovery and 24 hours hospitalisation. Materials and methods: Medical records of dogs that underwent brachycephalic obstructive airway surgery over two consecutive years (June 2017 to May 2019) were reviewed retrospectively. Signalment, clinical signs, diagnostic findings, surgical procedures and postoperative respiratory complications were recorded. Data were compared using the chi-squared or Fisher's exact tests. Results: Sixty-three dogs met the inclusion criteria for the study. Forty-two dogs underwent owner-assisted recovery and 21 dogs standard recovery. No statistical difference was found between groups in age, breed, gender, severity of respiratory or gastrointestinal clinical signs and surgical techniques employed. The incidence of postoperative complications was higher in dogs that received standard recovery (28%) compared to dogs recovered with the owners (2%). None of the dogs recovered with the owners and discharged the same day required veterinary assistance after discharge from the hospital. Clinical significance: Corrective surgery for brachycephalic obstructive airway syndrome was associated with lower postoperative respiratory complications when dogs were discharged on the same day after recovery with the owners. Owner-assisted recovery and early discharge are possible and safe and may decrease the incidence of postoperative complications. However, other unmeasured factors may have contributed to the lower complication rate in dogs recovered with the owners during the course of this study.

Answer 58

An 8-year-old male neutered American English Coonhound was presented for a 2-day history of increased respiratory effort and rate with an occasional cough. Thoracic radiographs noted pleural effusion, which was chylous based on cytological and chemical evaluation. The dog also had a 2-year history of a slow growing fatty mass in the right cervical region. A CT scan confirmed the large cervical fat attenuating mass extending from the base of the skull to the cranial thorax and right axillary region with compression of vascular structures. Severe bilateral effusion and secondary pulmonary atelectasis was noted within the thoracic cavity. It was elected to surgically remove the cervical mass and place a PleuralPort within the thoracic cavity. The mass was diagnosed as a lipoma and its removal led to rapid and complete resolution of chylothorax. Based on the literature search, this is the first case report of chylothorax secondary to a cervical mass or subcutaneous lipoma.

Answer 59

Objectives: To describe the treatment of four dogs with splenophrenic shunts using percutaneous shunting vessel embolisation with Amplatzer vascular plugs II and IV and provide information on their clinical outcomes. Materials and methods: Dogs with splenophrenic shunts treated at a veterinary hospital from January 2019 to December 2022 were identified through a medical record search. Results: Six dogs with splenophrenic shunts were identified. Two dogs were excluded because they were treated with laparoscopic surgery. Four underwent percutaneous shunting vessel embolization with Amplatzer vascular plugs and were included in the case series. A sheath was placed in the left external jugular vein and a balloon catheter was advanced to the shunting vessel under fluoroscopy. Portal vein pressure was confirmed to be within an acceptable range during temporary balloon occlusion. Based on preoperative CT angiography and intraoperative contrast examination, Amplatzer vascular plugs II were selected for two dogs and IV were selected for two dogs. Under fluoroscopy, the plug was deployed into the shunting vessel, and angiography confirmed occlusion. In all cases, the increase in portal pressure after temporary occlusion was within the acceptable range, and complete occlusion of blood flow was possible with a single plug. There were no major procedure-related complications. No dogs developed post-ligation seizures or signs of portal hypertension. In addition, improvements in ammonia values were observed in all cases. Clinical significance: Percutaneous splenophrenic shunt embolisation using Amplatzer vascular plugs II and IV is technically feasible in dogs, and assessed by intra-procedure angiography, a single plug completely obstructed blood flow in all dogs. Based on the literature search, this is the first report describing Amplatzer vascular plugs for the treatment of splenophrenic shunts.

Answer 60

Objective: The aim of this study was to examine a method for measuring femoral trochlear morphology in dogs using ultrasonography, and survey femoral trochlear morphology in skeletally normal dogs. Study design: To examine the validity of ultrasonography, three raters measured the sulcus angle (SA; the angle between the medial and lateral facets) five times in five skeletally normal dogs. Intra- and interrater reliabilities were then calculated. We also calculated the correlation coefficient between SAs measured using ultrasonography and computed tomography (CT) or magnetic resonance imaging (MRI). Then, we surveyed the femoral trochlear morphology in skeletally normal dogs using ultrasonography. Results: The intra- and interrater reliability for SAs measured using ultrasonography was good, and the correlation coefficient between SAs measured using ultrasonography and CT, or MRI, was strong. In skeletally normal dogs, the SAs for osseous contours decreased until 6 months of age. However, the SAs for cartilaginous contours did not change during the growth period. Conclusion: The ultrasonographic measurement method is reliable for the evaluation of femoral trochlear morphology in dogs. The contour of the articular cartilage surface of the femoral trochlea is already determined early in life, and ossification of the articular cartilage of the femoral trochlea proceeds until 6 months of age. The results of this study will provide crucial information for the evaluation of femoral trochlear morphology in dogs.

Answer 61

Objectives: The aim of this study was to evaluate the post-sterilization dimensional accuracy of a standardized drilling guide, three-dimensionally printed using biocompatible methacrylate monomers. Study design: A mock surgical guide was designed and printed in five resins (n = 5/material) using a commercially available desktop stereolithography printer. Pre- and post-sterilization dimensions were measured for each sterilization method (steam, ethylene oxide, hydrogen peroxide gas), then statistically compared; p-value less than or equal 0.05 was considered significant. Results: While all resins produced highly accurate replicas of the designed guide, the amber and black resins were unaffected by any sterilization method (p ≥ 0.9). For other materials, ethylene oxide produced the largest dimensional changes. However, mean post-sterilization dimensional changes for all materials and sterilization methods remained less than or equal to 0.05mm CONCLUSION: This study demonstrated that post-sterilization dimensional change of evaluated biomaterials was minimal, and less than previously reported. Additionally, amber and black resins may be preferred to reduce post-sterilization dimensional change, as they were unaffected by any sterilization method. Given the results of this study, surgeons should feel confident using the Form 3B printer to create patient surgical guides. Furthermore, bioresins may provide safer alternatives for patients compared with other three-dimensional printed materials.

Answer 62

Objective: The aim of this study was to determine the accuracy of client recollection of their dogs' preconsultation status using clinical metrology instruments such as the Liverpool Osteoarthritis in Dogs (LOAD) and Canine Brief Pain Inventory (CBPI) questionnaires in dogs presenting to a referral orthopaedic clinic. Study design: This is a longitudinal prospective cohort study of client-owned dogs presenting for investigations of lameness (n = 217). LOAD and CBPI questionnaires were completed by the owners at the first consultation (T0). Owners were contacted at 2 (T1), 6 (T2), and 12 (T3) months and asked to recall their dogs' T0 status by completing another LOAD and CBPI questionnaire. The agreement between the T0 and recalled LOAD and CBPI scores was determined using the two-way mixed effects intraclass correlation coefficient (ICC). The Wilcoxon signed-rank test was used to determine the difference between scores. Results: For the LOAD scores, there was moderate agreement between T0 and T1 (ICC: 0.64) and T0 and T2 (ICC: 0.53) scores and poor agreement between T0 and T3 (ICC: 0.496). For the CBPI Pain Severity Scores, there was poor agreement between T0 and all three subsequent time points (ICC < 0.5). For the CBPI Pain Interference Scores, there was moderate agreement between T0 and T1 (ICC: 0.57) and T2 (ICC: 0.56) scores and poor agreement between T0 and T3 (ICC: 0.43). Conclusion: The LOAD and CBPI questionnaires are subject to recall bias. Studies reporting retrospectively acquired CMI data should be interpreted with caution.

Answer 63

Objective: The aim of this study was to describe partial parasagittal patellectomy for the surgical management of patellar luxation, including surgical technique, proposed indications, complications, and outcomes in a cohort of dogs. Study design: This is a single-center retrospective clinical case series. Methods: Medical records (2019-2020) of dogs presenting for patellar luxation were reviewed. Clinical signs, luxation direction and grade, preoperative imaging and intraoperative findings, and complications were retrospectively retrieved. Owners were contacted via questionnaire for medium- and long-term follow-up. Results: A total of 24 stifles in 19 dogs met the inclusion criteria. Intraoperative minor complications occurred in four stifles. A single minor complication occurred postoperatively with no major complications. Increased thickness and radiographic attenuation of the patellar ligament were noted in 14 stifles at radiographic reassessment. Re-luxation was not encountered, with long-term owner-assessed outcome as good to excellent in all cases. Conclusion: Partial parasagittal patellectomy, used in conjunction with block recession trochleoplasty and tibial tuberosity transposition, provided reliable resolution of patellar luxation in canine stifles with grade 2 or 3 luxation where width mismatch between the patella and the trochlea was noted intraoperatively. Long-term outcome appears to be good to excellent with a low rate of complication.

Answer 64

Objective: The aim of this study was to evaluate the biomechanical effects of transfixation pin positioning in acrylic columns of external skeletal fixators (ESF). Study design: Twenty-four type I acrylic ESF were built simulating a fracture gap-model. Transfixation pins were placed centric (n = 12) or eccentric at ¼ of the column diameter (n = 12) in the acrylic columns. Six constructs from each group were subjected to axial compression and four-point bending tests. Stiffness, yield load and mode of failure were recorded. Results: Stiffness was not influenced by centring (p = 0.373), but it was higher in four-point bending than in axial compression (p < 0.001). Pin positioning had no influence on the yield (p = 0.535) and failure loads (p = 0.715) in axial compression, nor on the yield load in bending (p = 0.135). Eccentric pin positioning decreased failure loads by 28% in bending (p < 0.001). Conclusion: Eccentric position of transfixation pins within the acrylic columns alters the biomechanical properties of type I ESF constructs. While acrylic offers several advantages, when forming the columns, frame strength will be optimized if pins are centrally located.

Answer 65

Objective: The aim of this study was to determine the influence of time between the beginning of clinical signs, presentation and decompression, and combinations of several factors on the outcome and recovery of dogs undergoing surgery for thoracolumbar intervertebral disk extrusion (IVDE). Study design: In all, 433 client-owned dogs treated for IVDE between 2016 and 2020 were reviewed for signalment, neurological grade, rate of onset, duration of clinical signs, and surgical variables. Time from presentation to surgery was divided into three categories: S1 (0-12 hours), S2 (12-24 hours), and S3 (>24 hours). These variables were investigated to determine their influence on the return of pain sensation, urinary continence, ambulation and overall outcome. Results: A significant association was found between an acute onset of clinical signs, worse neurological grade at presentation and poorer outcomes. There was a significant difference between S1, S2, and S3 in neurological grade at presentation (p < 0.001) and at discharge (p < 0.001); however, the latter was no longer significant when adjusted for the grade at presentation (p = 1,000). Disk fenestration was associated with a faster return to ambulation (p = 0.033). Duration of clinical signs and time of surgery did not correlate with the time to recovery and return of pain sensation, urinary continence, or ambulation. Conclusion: Dogs presented with severe neurological status and/or rapid onset of clinical signs were operated on more promptly, but their outcomes were also poorer. There was no significant evidence for a better outcome when surgery was not delayed.

Answer 66

Objective: An increased rate of surgical site infection (SSI) following treatment of canine humeral intracondylar fissure (HIF) with a lateromedially (LM) placed transcondylar screw (TCS) compared with a mediolateral (ML) TCS has been previously postulated. We hypothesized that the direction of insertion of the TCS would not affect the incidence of postoperative SSI. Study design: It was single-centre retrospective study. Dogs with HIF confirmed by computerized tomography, treated by TCS placement (between 2008 and 2019) and with a minimum follow-up of 12 weeks, were included. The following data were recorded: signalment, presenting clinical signs, direction of placement and size of the utilized TCS, surgical and anaesthetic times, concurrent surgical procedures, presence of concomitant elbow pathology, perioperative and postoperative antibiotic usage and postoperative complications. Recorded data were analysed with a multinomial logistic regression model with a p-value less than or equal to 0.05. Results: Thirty-five dogs (46 elbows) met the inclusion criteria. Median clinical follow-up interval was 52 weeks. Seven of thirty-one elbows with a ML TCS, and 4/15 elbows with a LM TCS developed SSI. Four of nine dogs that underwent bilateral single-surgery TCS placement developed SSI unilaterally. Conclusion: No significant difference was shown in short-term SSI occurrence between the ML and the LM direction of placement of the TCS.

Answer 67

Objective: The aim of this study was to develop a three-dimensional (3D) model to identify the isometric component of the cranial cruciate ligament (CCL) in dogs. Methods: A static 3D model of the specimen was generated from a computed tomography scan of the stifle of a dog and a kinematic model was generated from data collected, every 5 degrees from full extension (131 degrees) through 80 degrees of stifle flexion, from four sensors attached to the tibia. Kinematic data were superimposed on the static model by aligning the points of interest, which were defined for both models. This allowed the tibia to rotate and translate relative to the femur based on the kinematic data. The contours of the distal femur and proximal tibia were converted into point clouds and the distance between each point in the femoral point cloud and all the points in the tibial point cloud were measured at each of the 15 positions. The difference between the maximum and minimum distances for each pair of points was calculated, and when it was less than 0.2 mm, points were illustrated as two red dots connected by a line at their locations on the femur and tibia. Results: A total of 3,681 pairs of isometric points were identified and were located at the origin and insertion of the CCL and on the lateral aspect of the stifle. Conclusion: Isometric areas are present at the origin and insertion of the CCL and lateral aspect of the stifle. Better understanding of these locations may lead to refinements in techniques to replace the ruptured CCL.

Answer 68

Objective: To compare the analgesic effect of surgical wound infiltration with liposomal bupivacaine (LB) to saline placebo in dogs after tibial plateau leveling osteotomy (TPLO). Study design: Blinded, randomized, placebo-controlled clinical prospective study. Animals: Fifteen client-owned dogs receiving LB and 17 dogs receiving an equivalent volume of saline placebo, all with confirmed unilateral cranial cruciate ligament insufficiency. Methods: Preoperatively and up to 48 h after surgery, Glasgow Composite Measure Short Form (CMPS-SF) pain scores were assigned and using a weight distribution platform, static bodyweight distribution (%BWdist ) to the operated limb was measured. Postoperatively, dogs also received carprofen 2.2 mg/kg subcutaneously every 12 h. Rescue analgesia was provided. Treatment success was defined as not requiring rescue analgesia over the 48-h postoperative period. Results: There was no difference between treatment success, postoperative opioid consumption, CMPS-SF pain scores, or %BWdist in dogs that received surgical wound infiltration with LB compared with those receiving saline placebo, following TPLO. There was no linear correlation between CMPS-SF pain scores and %BWdist . Conclusion: For the population of dogs that underwent TPLO and received postoperative carprofen at our institution, LB did not provide an analgesic effect discernable by success/failure analysis, CMPS-SF pain scores, or %BWdist measurement using a weight distribution platform, compared with saline placebo. Clinical significance: LB may not provide detectable analgesia during the first 48 h for dogs recovering from TPLO and receiving only postoperative carprofen.

Answer 69

Objective: To report the outcome of double pelvic osteotomy (DPO) for craniodorsal luxation of total hip replacement (THR). Study design: Retrospective case series. Animals: Eleven client-owned animals. Methods: Dogs with craniodorsal luxation of THR and high angle of lateral opening (ALO) were considered candidates for DPO. The ALO and the version angle (VA) were measured on pre- and post-DPO radiographs. Pre- and post-DPO ALO and VA were compared using a Wilcoxon signed-rank test. Clinical and radiographic outcomes were assessed at 2 and 6 months post-DPO. Results: Eleven DPOs were performed on 11 dogs after THR luxation. The ALO was reduced from a median of 66.2° (range 37.3-73.1°) to 55.9° (range 13.2-60.0°) (p ≤ .001), and VA increased from a median of 25.6° (range 6.8-51.9°) to 35.3° (range 15.1-51.7°) (p ≤ .03). Craniodorsal luxation recurred in five dogs and was managed with closed reduction (one dog), capsulorrhaphy (one dog), or repositioning of the acetabular cup (three dogs). The median clinical follow-up duration was 19.7 months (range 3.4-73.0). In the long term, seven dogs required explantation (five aseptic loosenings, two infections) (median 8.2 months, range 2.6-50.6). Conclusion: Reluxation was frequent after DPO, 5/11 dogs requiring additional procedures, including three cup revisions. The long-term outcome was considered to be poor due to frequent explantation. Clinical significance: Double pelvic osteotomy may be considered to avoid cup replacement when managing craniodorsal THR luxations in dogs but is not recommended due to high complication rates.

Answer 70

Objective: To evaluate the feasibility of feline diagnostic coxofemoral arthroscopy. Study design: Ex vivo feline cadaveric descriptive study. Animals: Seven feline cadavers (14 hips). Methods: Gross dissection of two feline hips was performed to evaluate anatomic landmarks, guide arthroscopic portal development, and determine optimal limb positioning. A 1.9 mm, 0° arthroscope, inserted through a supratrochanteric lateral portal, was used to assess intraarticular structures in 12 feline cadaver hips. Arthroscopy was followed by gross dissection of periarticular soft tissues. Relative portal locations and damage to periarticular structures were recorded. Hips were disarticulated, and an India ink assay was performed to assess whether there was iatrogenic cartilage injury (ICI). Results: Scope insertion was achieved in all hips. Articular cartilage of the femoral head and acetabulum, round ligament, joint capsule, transverse acetabular ligament, and dorsal acetabular rim were identified arthroscopically in all hips. Probe insertion and intra-articular structure palpation was achieved in all hips. Scope and instrument portals resulted in minimal periarticular muscle trauma. No sciatic nerve damage was detected. Minor partial thickness ICI was observed in all hips at the site of scope insertion. Focal full thickness ICI was noted in one hip. Conclusion: Arthroscopy of the feline coxofemoral joint allowed visual and probe evaluation of intra-articular structures without evidence of major periarticular neurovascular trauma. Iatrogenic cartilage injury occurred in all hips but severity of lesions was considered mild. Clinical significance: Coxofemoral arthroscopy is feasible in cats and can be utilized as a diagnostic tool for minimally invasive joint evaluation.

Answer 71

Objective: To evaluate the accuracy of a 3-dimensionally (3D)-printed custom endoscopy port (3DEP) for minimally invasive cervical ventral slot decompression. Study design: Cadaveric study. Animals: Fifteen cadavers of dogs weighing between 3.1 and 34.4 kg. Methods: Minimally invasive cervical ventral slots were created using a 3DEP and an endoscopic system at the C3-C4 intervertebral disc space in each dog by 1 experienced and 1 inexperienced surgeon. Postoperative computed tomography was performed to compare the planned and postoperative screw trajectories (angle, entry point, exit point, and length of the screw entering the spinal canal) and quantify slot formation dimensions. Results: Thirty screws were inserted in 30 vertebral bodies. Mean screw angle deviation was less than 2.5°, entry and exit point deviation was less than 1.6 mm, and length of the screw entering the spinal canal was less than 0.6 mm. No differences were identified between the experienced and inexperienced surgeons. Ventral slot length ratio was 30.15 ± 1.86 for the experienced surgeon and 29.38 ± 1.61 for the inexperienced surgeon (p = .372). The mean ventral slot width ratio was 45.60 ± 1.80 for the experienced surgeon and 47.20 ± 1.54 for the inexperienced surgeon (p = .261). Conclusion: Screw positioning and creation of ventral slots were accurately performed using the 3DEP by both inexperienced and experienced surgeons. Clinical significance: The use of a 3DEP for minimally invasive cervical ventral slot decompression may be an alternative to the conventional ventral slot in dogs. Additional studies are needed to evaluate efficacy and safety.

Answer 72

Objective: To report small intestinal herniation through the epiploic foramen in a dog. Animals: Nine-year-old male castrated Shih Tzu. Study design: Case report. Methods: The dog presented with an 8-year history of vomiting and regurgitation and acute onset of melena, lethargy, anorexia, anemia, and suspected gastrointestinal mass or obstruction on prereferral imaging. Abnormalities on abdominal radiographs included a large, midcaudal soft tissue structure and cranial displacement and segmental dilation of the small intestine. On abdominal ultrasound, severe gastric dilation, jejunal tortuosity and stacking, and peritoneal effusion were observed. Epiploic herniation of the small intestine and segmental jejunal devitalization was diagnosed on exploratory laparotomy, and the dog underwent hernia reduction, jejunal resection and anastomosis, and nasogastric tube placement. Results: Severe gastric distention and atony persisted 24 h after surgery, despite medical management. The dog was taken to surgery for decompressive gastrotomy and placement of gastrostomy and nasojejunostomy tubes for postoperative decompression and feeding, respectively. Three days after the original surgery, the dog developed a septic abdomen from anastomotic dehiscence and underwent jejunal resection and anastomosis and peritoneal drain placement. Gastric dysmotility gradually resolved with the administration of motility stimulants, removal of gastric residual volume, and nutritional support via nasojejunostomy tube feedings. Three months after discharge, the dog was clinically normal. Conclusion: Epiploic foramen entrapment should be considered a type of herniation in dogs. Clinical suspicion should be raised in dogs with unresolving regurgitation and vomiting, visceral displacement, and stacking and distension of small intestine.

Answer 73

Objective: To describe a naso-facial reconstruction technique following bilateral rostral maxillectomy and its functional and cosmetic outcomes. Animals: Two dogs. Study design: Clinical case series. Methods: Two dogs were presented with a right rostral maxillary mass. Preoperative biopsy and staging revealed a biologically high-grade and histologically low-grade fibrosarcoma (Hi-Lo FSA). A combined nasal planectomy and radical bilateral rostral maxillectomy was performed sparing the labial/buccal mucocutaneous flaps bilaterally. Surgery resulted in asymmetry of the width of the flaps; the narrower flap was rotated medially to reconstruct the lip and create an oral vestibule. The wider flap was rotated medially to cover the remaining dorsolateral opening of the nasal conchae. The flaps overlapped in a parallel manner, discretely concealing the nasal passages, and separating them from the oral cavity. Hemorrhage occurred in both dogs, with one dog requiring a blood transfusion postoperatively. Results: Oral Hi-Lo FSA with tumor-free margins was confirmed in both dogs. Both dogs recovered uneventfully within 4 weeks. Owners reported being very satisfied with the functional (return to normal exercise/activities and uncompromised respiration) and cosmetic outcomes. Based on the owners' telephone follow up, no tumor recurrence was noted at 15 (Dog 1) and 6 (Dog 2) months postoperatively. Conclusion: The full-thickness bilateral labial/buccal rotational flaps were used successfully to reconstruct the rostral maxilla, external nose and facial defects involving the nasal cavity. The technique resulted in acceptable functional and cosmetic outcomes and can be considered for naso-facial reconstruction in selected cases.

Answer 74

Objective: To assess the incidence of transcortical fracture (TCF) development based on screw insertion angle and screw insertion speed. Study design: Cadaveric experimental study. Sample population: Sixty-six canine tibiae. Methods: Sixty-six cadaveric tibiae were randomly assigned to one of six groups that varied based on screw insertion angle relative to the pilot hole (0, 5, or 10°) and screw insertion speed (650 or 1350 revolutions per minute [rpm]). Each tibia was mounted in a custom jig. Locking self-tapping screws (3.5 mm) were inserted at varying speeds and insertion angles, based on group assignment. Orthogonal radiographs were evaluated for TCFs. Fisher's exact tests with a Bonferroni correction were performed to evaluate differences in the frequency of TCF between groups. Results: In Group A (0°/650 rpm: control), a 0% TCF rate was observed (n = 0/80). Group B (5°/650 rpm) had a 3.75% TCF rate (n = 3/80). Group C (10°/650 rpm) had a 12.5% TCF rate (n = 10/80). Group D (10°/hand insertion) had a 3.75% TCF rate (n = 3/80). Group E (10°/1350 rpm) had a 17.5% TCF rate (n = 14/80). Group F (0°/1350 rpm) had a 0% TCF rate (n = 0/80). Groups C and E had the highest TCF rates with a difference in TCF rates observed between the control group and Group C (p = .001) and between the control group and Group E (p < .001). Conclusion: Increased screw insertion angle and insertion speed appear to be predisposing factors for TCF development in cadaveric bone. Clinical significance: Ensuring screw insertion is coaxial with the pilot hole and using slower screw insertion speeds may help reduce the risk of TCF development.

Answer 75

Objective: To evaluate the effects of three adjunctive methods of tension band wire fixation (TBWF) on the biomechanical properties, gap formation, and failure mode in simulated canine patella tendon rupture (RPT). Study design: Randomized, ex vivo. Sample population: Paired hindlimbs from 32 dog cadavers. Methods: Patellar tendons (PTs) and associated bone-muscle-tendon units were harvested. Each PT was transected then sutured using a core locking loop and simple continuous epitendinous pattern. Each hindlimb was randomly assigned to one of three groups (n = 18 hindlimbs/group) using 18 gauge 316 L wire, anchored to the tibial crest distally, to perform transpatellar, suprapatellar, or combined tension band-wire (TBW) augmentation. Ten hindlimbs were utilized as control specimens. Yield, peak, and failure loads, stiffness, loads to 1 and 3 mm gap formation, and failure mode were evaluated. Results: Combined transpatellar and suprapatellar TBW augmentation was superior to transpatellar or suprapatellar groups alone. Yield (p = .0008), peak (p = .004), and failure loads (p = .005) were greater for the combined group than for the transpatellar (p = .048) and suprapatellar groups (p = .01) respectively. There was no difference regarding the occurrence of 1 or 3 mm gap formation (1 mm, p = .05; 3 mm, p = .06); however, loads required to cause gap formation were greater in the combined group (p = .036). Mode of failure differed between techniques used for PT augmentation (p < .001). Conclusion: Combined transpatellar and suprapatellar adjunctive TBW augmentation for simulated PT repairs was biomechanically superior to either transpatellar or suprapatellar TBWF alone. Clinical significance: Combined suprapatellar and transpatellar TBWF may offer a viable surgical option for increased repair-site strength and greater loads to gap formation. Further studies investigating alternative techniques and materials for RPT repair augmentation are warranted.

Answer 76

Objective: To describe a craniectomy using a lateral, transzygomatic approach to the middle fossa and rostral brainstem, and to report clinical outcomes and complications in three dogs. Animals: Two cadaver dogs and three client-owned dogs. Two of the client-owned dogs with middle fossa lesions, and one with a rostral brainstem lesion. Methods: Two cadavers were used to describe the lateral, transzygomatic surgical approach to the middle fossa and rostral brainstem. The medical records of three dogs undergoing this surgical approach were reviewed for data on signalment, preoperative and postoperative neurological status, diagnostic imaging, surgical technique, complications, and outcome. Results: Indications for this surgical approach included incisional biopsy (n = 1) and debulking surgery for brain lesions (n = 2). Definitive diagnoses were achieved in two cases, and tumor volume reduction in all cases. Two of the three dogs developed postoperative facial nerve paralysis ipsilateral to the surgical site, which resolved within 2 and 12 weeks after surgery. Conclusion: The lateral, transzygomatic approach provided useful access to ventrally located cerebral/skull base lesions in dogs without major complications.

Answer 77

Objective: To assess the accuracy of CT angiography (CTA) in predicting resectability, degree of surgical difficulty, and individual factors that may impact resectability of isolated hepatic masses in dogs. Animals: Prospective study of 20 dogs with 21 isolated hepatic masses. Procedures: All CTAs and surgeries were performed between June 16, 2013, and November 30, 2016, at The Animal Medical Center in New York. Preoperative CTA images were evaluated by a board-certified surgeon (n = 2). A preoperative assessment was completed, documenting several predetermined factors aimed at predicting resectability of each mass and the degree of surgical difficulty. Resectability was divided into gross resectability and complete histologic excision. Following surgery, the surgeon completed a postoperative assessment documenting the intraoperative findings. Independently, a blinded board-certified radiologist analyzed the images and completed an identical preoperative assessment. Results: The radiologist was more accurate in lesion localization compared to the surgeon (P = .023). Seventeen (17/21) masses were grossly resectable in surgery. Two additional (2/21) masses that were deemed grossly resectable were incompletely excised on histopathologic analysis. Both the surgeon and radiologist were accurate in their prediction of gross resectability and complete excision. Major vascular involvement, multilobar involvement, and right-sided laterality negatively affected resectability. The surgeon was significantly more accurate in predicting the degree of surgical difficulty (κ = 0.50) when compared to the radiologist (κ = 0.38). Clinical relevance: Preoperative CTA of isolated hepatic masses is useful in prediction of surgical difficulty and resectability, as well as identifying several factors that impact resectability.

Answer 78

Objective: To describe the management of extensive hepatectomy in 2 dogs. Animals: A 10-year-old female intact mixed-breed dog (case 1) and an 11-year-old male castrated mixed-breed dog (case 2) were presented for surgical evaluation following diagnosis of a hepatic mass. Clinical presentation, progression, and procedures: 16 months before presentation, case 1 had undergone a left lateral liver lobectomy, which resulted in an incomplete resection of hepatocellular carcinoma. Both dogs underwent surgical excision of the liver mass. Treatment and outcome: In case 1, surgery consisted of the removal of the remaining left medial lobe, as well as the central division. Case 2 received a complete left and central division hepatectomy. Histopathology confirmed a diagnosis of hepatocellular carcinoma in both dogs. Liver enzyme resolution and lack of tumor recurrence were confirmed with chemistry panel and abdominal ultrasonography in both dogs. Clinical relevance: This case report describes, for the first time, the clinical management and outcome of extensive hepatectomy in 2 dogs. We propose that extensive hepatectomy, staged or synchronous, is possible in a clinical setting.

Answer 79

Abstract Objective: To evaluate the clinical outcomes associated with the Biomedtrix Centerline canine cementless total hip arthroplasty implant (C-THA). Animals: 17 dogs (20 hips) surgically implanted with C-THA to treat coxofemoral pathology. Clinical presentation and procedures: Dogs with C-THA (2015 through 2020) with follow-up of ≥ 6 months were evaluated. Data included signalment, complications, management of complications, radiographs (bone implant interface), and clinical outcomes. Outcomes were assessed radiographically and subjectively via surgeon orthopedic examinations. Results: 15 of 20 (75%) with long term radiographic follow-up had an excellent outcome. 5 hips (25%) had postoperative complications: femoral neck fracture (n = 1; 5%), aseptic loosening (2; 10%), and septic loosening (2; 10%). Clinical relevance: C-THA can restore function in dogs with coxofemoral pathology. This novel procedure showed outcomes comparable to initial reports of other traditional THA implants (cemented, cementless, and hybrid) but complications occurred at a higher rate than recent outcomes of other long-standing THA procedures. Increased case numbers and surgeon experience with this novel implant system may eventually yield results comparable to other accepted THA systems.

Answer 80

Objective: To compare the use of the video telescope operating monitor (VITOM) and use of a conventional unassisted surgical method for treatment of cervical intervertebral disc herniation in dogs. Animals: 39 dogs with cervical intervertebral disc disease. Methods: Prospective study. Dogs were prospectively nonrandomly assigned to either the VITOM (n = 19) or conventional surgery (20) group depending on VITOM system availability. Signalment and preoperative neurologic status were recorded for all dogs. Preoperative and postoperative CT myelography was performed to compare intervertebral space location, spinal cord dimensions at the decompression level, ventral slot dimensions, and residual disc material. Surgical complications and postoperative neurologic outcomes were recorded. Data were compared between the 2 groups using fixed-effects or mixed-effects models to consider double reading of CT myelography images. Results: No significant differences were noted between the 2 groups regarding the decompression ratio (P = .85), vertebral length body ratio (P = .13), ventral slot width ratio (P = .39), residual disc material (P = .30), and sinus bleeding (P = .12). No significant differences were found between the 2 groups regarding postoperative neurologic grade (P = .17). Clinical relevance: VITOM-assisted ventral slot decompression is equivalent to conventional surgery in treatment of cervical intervertebral disc herniation in dogs. The use of VITOM remains a good alternative to the conventional surgical method.

Answer 81

Objective: To retrospectively evaluate complications reported in dogs and cats with a closed suction subcutaneous drain that were either managed completely in hospital (Group ND) or discharged home for ongoing outpatient care (Group D). Animals: 101 client-owned animals involving 94 dogs and 7 cats with a subcutaneous closed suction drain placed during a surgical procedure. Procedures: Electronic medical records (January 2014 to December 2022) were reviewed. Signalment, reason for drain placement, surgical procedure, location and duration of drain placement, drain discharge status, antimicrobial usage, culture and sensitivity results, and intraoperative and postoperative complications were recorded. Associations among variables were evaluated. Results: There were 77 animals in Group D and 24 animals in Group ND. Majority (n = 21/26) of complications were classified as minor and were all from Group D. Length of hospitalization in Group D (1 day) was significantly shorter than Group ND (3.25 days). Duration of drain placement was significantly longer in Group D (5.6 days) than Group ND (3.1 days). There were no associations between drain location, drain duration, or surgical site contamination with risk of complications. Clinical relevance: There is a higher risk of complications associated with discharging an animal from hospital (37%) with a subcutaneous closed suction drain than removing it prior to discharge (4%). These complications, however, were primarily minor and easily managed. Discharging an otherwise stable animal to home with a subcutaneous closed suction drain may be feasible to decrease duration of hospitalization, cost to the owner, and stress for the animal.

Answer 82

Objective: To assess the effect of tibial compression on radiographic cranial tibial translation measurements in healthy dogs and those with cranial cruciate ligament (CCL) rupture and establish specific criteria for the radiographic diagnosis of CCL rupture. Animals: 60 dogs. Procedures: Dogs were divided into 3 groups with 20 dogs each: group 1, healthy adult dogs; group 2, adult dogs with CCL rupture; and group 3, healthy young dogs. For each dog, 2 images of the stifle joint in mediolateral projection were taken, of which 1 was conventional and 1 was under tibial compression. Variables were measured in each radiographic projection: the patellar ligament angle, the patellar ligament insertion angle, the angle of tibial translation measured by 2 different methods, and the linear distance between the points of CCL origin and insertion (DPOI). Additionally, a novel variable, DPOI ratio, was evaluated. Results: Regarding radiographic positioning, tibial compression significantly changed most of the variables in the within-group comparison. The variable DPOI were not different with and without tibial compression in the group of healthy adult dogs but were different for dogs with CCL rupture. Thus, these are important parameters in the diagnosis of CCL rupture. In the analysis of a novel variable, DPOI ratio, dogs with CCL rupture could be distinguished from healthy dogs at a high level of specificity and sensitivity. Clinical relevance: DPOI ratio values above 1.18 were consistently indicative of CCL rupture, thus allowing for a precise radiographic diagnosis of the condition.

Answer 83

The purpose of this manuscript, which is part of the Currents in One Health series, is to take a comparative approach to stem cell treatment for tendon injury and consider how the horse might inform treatment in other veterinary species and humans. There is increasing experimental and clinical evidence for the use of bone marrow-derived mesenchymal stem cells to treat tendon injuries in the horse. The same evidence does not currently exist for other species. This manuscript will review why the equine superficial digital flexor tendon core lesion might be considered optimal for stem cell delivery and stem cell interaction with the injury environment and will also introduce the concept of stem cell licensing for future evaluation. The companion Currents in One Health by Koch and Schnabel, AJVR, October 2023, addresses in detail what is known about stem cell licensing for the treatment of other diseases using rodent models and how this information can potentially be applied to tendon healing.

Answer 84

Objective: To report perioperative characteristics and outcome following bilateral, single-session, laparoscopic adrenalectomy (BSSLA) in dogs. Animals: Client-owned dogs (n = 6). Clinical presentation and procedures: Medical records were reviewed and perioperative data collected, including preoperative diagnostic imaging, operative details, complications, and need for conversion to open laparotomy. Bilateral, single-session, laparoscopic adrenalectomy was performed on the right or left side with a standard 3- or 4-portal transperitoneal technique. The dog was repositioned to contralateral recumbency, and laparoscopic adrenalectomy was repeated. Follow-up information was collected by telephone interviews with the owners and/or referring veterinarian. Results: Median age and weight of dogs were 126 months and 14.75 kg, respectively. Contrast-enhanced CT (CECT) was performed in all dogs. Median maximal tumor diameter was 2.6 and 2.3 cm for the right and left-sided tumors, respectively. Median surgical and anesthesia times were 158 and 240 minutes, respectively. Conversion to open laparotomy was performed in 1 dog following renal vein laceration during initial adrenalectomy. Left adrenalectomy and ureteronephrectomy were performed, and the right adrenal tumor was left in situ. Cardiac arrest occurred in 1 dog following initial adrenalectomy (left); however, the dog was resuscitated successfully, and contralateral laparoscopic adrenalectomy was performed without complication. All dogs survived to hospital discharge. Follow-up ranged from 60 to 730 days (median, 264 days) for dogs that successfully underwent BSSLA. Clinical relevance: BSSLA was associated with favorable outcomes in this cohort of dogs. Laparoscopy may be considered in dogs with bilateral, modestly sized, noninvasive adrenal tumors.

Answer 85

Objective: To describe the clinical characteristics, procedural techniques, complications, and outcomes of dogs and cats undergoing any of the following modified hemipelvectomy techniques: concurrent partial sacrectomy and/or partial vertebrectomy, osseous excision crossing midline, and reconstruction without the use of local musculature. Animals: 23 client-owned animals (20 dogs and 3 cats) that underwent modified hemipelvectomy techniques. Animals that underwent traditional (nonmodified) hemipelvectomy techniques were excluded. Procedures: The medical records of 3 academic institutions were reviewed, and data were recorded and analyzed. Results: Modified hemipelvectomy was performed with partial sacrectomy and/or vertebrectomy in 11 dogs, excision crossing pelvic midline with concurrent limb amputation in 5 dogs and 2 cats, and closure without use of native muscle or mesh in 4 dogs and 1 cat. Surgery was performed for tumor excision in all cases. Excision was reported as complete in 16 of 23, incomplete in 6 of 23, and not recorded in 1 of 23 animals. All animals survived to discharge. Only animals undergoing partial sacrectomy/vertebrectomy (4/11) experienced postoperative mobility concerns. Major intra- or post-operative complications (grades 3 and 4) occurred in 2 dogs that underwent partial sacrectomy/vertebrectomy, and 1 of these animals experienced a complication that resulted in death. The median time to death or last follow-up was 251 days (range, 3 to 1,642). Clinical relevance: The modified hemipelvectomy techniques reported in this cohort were overall well tolerated with good functional outcomes. These findings support the use of these modified hemipelvectomy techniques in dogs and cats, and previous notions regarding tolerable hemipelvectomy procedures should be reconsidered. However, additional studies with larger numbers of patients undergoing modified hemipelvectomy techniques are needed to gain more information.

Answer 86

Objective: To evaluate short- and long-term outcomes for dogs undergoing anal sacculectomy for massive (> 5 cm) apocrine gland anal sac adenocarcinoma (AGASACA). Animals: 28 client-owned dogs with massive AGASACA. Procedures: A retrospective multi-institutional study was performed. Pre-, intra-, and post-operative data was collected, and variables were statistically analyzed for associations with progression-free interval (PFI) and overall survival (OS). Results: At the time of anal sacculectomy, 19 (68%) dogs underwent concurrent iliosacral lymph node extirpation, including 17 of 18 (94%) dogs with suspected nodal metastasis preoperatively. Five (18%) dogs experienced grade 2 intraoperative complications. Ten (36%) dogs experienced postoperative complications, including 1 grade 3 and 1 grade 4 complication. No dogs had permanent fecal incontinence, tenesmus, or anal stenosis. Nineteen dogs received adjuvant chemotherapy, radiation, or both. Local recurrence occurred in 37% of dogs. Dogs with lymph node metastasis at surgery were more likely than dogs without metastasis to develop new/progressive lymph node metastasis (10/17 [59%] vs 0/10 [0%]; P = .003) and distant metastasis (7/17 [41%] vs 0/10 [0%]; P = .026). Median PFI was 204 days (95% CI, 145 to 392). Median OS was 671 days (95% CI, 225 to upper limit not reached). Nodal metastasis at the time of surgery was associated with shorter PFI (P = .017) but not OS (P = .26). Adjuvant therapy was not associated with outcome. Clinical relevance: Dogs with massive AGASACA experienced prolonged survival following anal sacculectomy despite a high incidence of local recurrence and metastasis. Lymph node metastasis at the time of surgery was a negative prognostic indicator for PFI but not OS.

Answer 87

Objective: To prospectively evaluate clinical outcomes using acellular fish skin grafts (FSGs) for the management of complete wound healing by secondary intention after wide surgical excision of skin tumors in dogs. Animals: 5 dogs undergoing wide surgical excision of skin tumors on the distal extremity. Clinical presentation and procedures: FSGs were applied to surgical wound beds following wide excision of the tumor. Bandages were changed weekly and additional grafts placed when integration of the previous graft was complete. The wounds were assessed for the following: dimensions, tissue health (color), time to complete epithelialization, complications, and tumor recurrence. Results: All masses were excised with 2-cm lateral margins and 1 fascial plane deep to the tumor. Tumor diagnoses included 3 mast cell tumors and 2 soft tissue sarcomas. Surgical wounds had a median area of 27.6 cm2 (range, 17.6 to 58.7 cm2). The median number of FSG applications was 5 (range, 4 to 9 applications). Complete epithelialization occurred within 7 to 9 weeks for uncomplicated wounds (3 of 5) and 12 to 15 weeks for complicated wounds (2 of 5) that sustained self-trauma. There were no adverse events related to the use of FSGs. Local recurrence was not seen over a follow-up period ranging from 239 to 856 days. Clinical relevance: Wide surgical excision of distal extremity skin tumors, followed by repeated application of acellular FSGs, resulted in complete healing of all wounds with no adverse events. This treatment method does not require advanced reconstructive surgical skills and may be useful for the management of skin tumors on the distal extremities.

Answer 88

Objective: To describe the diagnostic findings, surgical techniques, and outcomes of thoracolumbar vertebral instability associated with or without articular process (AP) anomalies in Pekingese dogs. Animals: 11 client-owned Pekingese dogs. Procedures: Medical records (2007 to 2022) were reviewed. Inclusion criteria were Pekingese dogs with thoracolumbar vertebral instability that underwent decompressive laminectomy and vertebral stabilization. Dynamic myelographic study and/or intraoperative spinal manipulation were used to diagnose vertebral instability. Data on preoperative and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes were retrieved. Results: The dogs presented with paraparesis (n = 9) or paraplegia (2). Five dogs had caudal AP anomalies. Dynamic myelographic study demonstrated single (n = 7) or multiple (4) dynamic compressions with poststress spinal cord height reduction (median, 12.5%; IQR, 6.8% to 21.2%). Of the 17 dynamic compression lesions, 5 lesions were at the disc spaces with caudal AP abnormalities. All dogs had vertebral instability confirmed by intraoperative spinal manipulation and underwent hemilaminectomy and unilateral vertebral stabilization. One dog had adjacent segment vertebral instability and underwent vertebral stabilization 3 months after the initial operation. All but 1 dog showed successful outcomes at the last follow-up (median, 16 months; IQR, 3 to 32 months). Clinical relevance: Vertebral instability associated with or without AP abnormalities is a potential cause of thoracolumbar spinal cord injury in Pekingese dogs. Dynamic myelographic studies and/or intraoperative spinal manipulation demonstrated vertebral instability. Spinal cord decompression and vertebral stabilization are effective, resulting in neurologic improvements in most dogs.

Answer 89

Objective: To compare the prognosis of small dogs with cervical intervertebral disc herniation (C-IVDH) when treated with ventral slot decompression (VSD) alone or with concomitant vertebral fixation (VF). Animals: Small dogs (n = 303) weighing < 15 kg diagnosed with C-IVDH and treated with VSD. Procedures: We recorded signalment, cervical myelopathy grade, surgical site, use of VF, degree of adjacent disc degeneration, recovery, recurrence, recurrence site, and postoperative course, including the time elapsed from recovery to recurrence. We examined factors associated with recovery and recurrence during the 30-month postoperative period using multivariate logistic regression analysis. Results: VF did not affect recovery (P = .79). However, nonchondrodystrophic breeds had poorer recovery (OR, 5.89; P = .023) than chondrodystrophic breeds, and a higher preoperative cervical myelopathy grade (grade 3 or 4) was associated with poorer recovery (OR, 7.09 or 3.46, respectively; P = .019 or .042, respectively), compared with grade 1. VF did not affect recurrence (P = .79); however, increasing age was associated with recurrence (OR, 1.79; P = .001). Clinical relevance: In small dogs weighing < 15 kg, there was no difference in postoperative recovery and recurrence rates after VSD with or without concomitant VF. Therefore, in small dogs with C-IVDH, even if the slot volume is increased to remove sufficient disc material during VSD, a good prognosis can be achieved with or without VF.

Answer 90

Objectives: The aim of the present study was to investigate whether diagnostic assessment methods used on radiographs in humans with slipped capital femoral epiphysis (SCFE) can be used in cats. Methods: The ventrodorsal (VD) extended-leg and VD frog-leg pelvic radiographs of 20 cats with SCFE without fully displaced femoral capital epiphyses (FCE), eight cats with fully displaced FCE and five control cats with normal pelvic anatomy were assessed by five observers on two separate occasions 3 months apart. The Klein's line and modified Klein's line were assessed on each VD extended-leg radiograph, and the S-sign was assessed on each VD extended-leg and VD frog-leg radiograph. Results: Excluding cases of fully displaced FCE, the S-sign on the VD frog-leg radiographs more accurately diagnosed SCFE than the S-sign on the VD extended-leg radiographs and the Klein's line (92.4% vs 88.8% vs 60.6%, respectively), and had the greatest sensitivity (93.9% vs 79.2% vs 30.6%, respectively). The S-sign on the VD extended-leg radiographs had greater specificity than the Klein's line and S-sign on the VD frog-leg radiographs (99.2% vs 97.9% vs 90.9%, respectively). The modified Klein's line detected SCFE in 40.2% of cases that were negative for the Klein's line. Conclusions and relevance: The S-sign in both VD extended-leg and VD frog-leg views successfully detected SCFE in cats and can be used to increase early diagnosis and treatment in cats with SCFE that have only subtle radiographic changes.

Answer 91

Objectives: The aim of this study was to determine whether an association existed between cephalometric measurements, maxillomandibular dental arch distances and the occurrence of traumatic malocclusions in the mandibular soft tissues of cats. Methods: Cats that had presented for dental consultations and that underwent cone-beam CT during diagnostic assessment were included in the study and categorised as cases and controls in a 1:2 ratio. Cases were designated as cats with a clinical diagnosis of malocclusion causing trauma to the buccal mandibular soft tissues or pyogenic granuloma secondary to the trauma, and controls were designated as cats with the absence of such diagnoses and without a history of other musculoskeletal anomalies in the head. Cephalometric measurements, including skull and facial indexes, as well as distances and angulations between dental crowns and crown tips, were calculated and analysed statistically. Results: In total, 72 cats (24 cases and 48 controls) were included in the study. Cephalometric measurements revealed a significant association between the skull and facial indexes and the occurrence of traumatic malocclusions in the caudal teeth. Brachycephaly was a strong predictor of the occurrence of traumatic malocclusions. In addition, the space between crown tips and teeth angulations was a contributing factor to the trauma. Conclusions and relevance: Cats with traumatic malocclusions in the cheek teeth tend to present a narrower interdental space between the maxillary and mandibular carnassial teeth, mostly attributed to skeletal and dental malocclusion. These findings can be used to help raise awareness about this disease in cats and its association with brachycephaly. Cut-off values have been proposed and could be used in the selection of cats by breeders to reduce the occurrence of this disease.

Answer 92

Objectives: The aims of the study were to investigate if feline middle ear anatomy can be visualized using endoscopy via a lateral bulla approach and to determine if scope-assistance increases rates of successful entry into the hypotympanum during feline total ear canal ablation and lateral bulla osteotomy (TECA-LBO). Methods: A total of 13 feline cadaver heads underwent CT to confirm the absence of pre-existing middle ear disease. For each head, an electronic coin toss was used to determine which ear would undergo endoscope-assisted TECA-LBO; a traditional TECA-LBO without the use of the scope was performed on the contralateral side. In endoscope-assisted procedures, a 1.9 mm scope was intermittently inserted into the tympanic bulla via a lateral bulla approach and used to identify middle ear structures, visualize the bony septum and confirm entry into the hypotympanum. After the bilateral TECA-LBO, the cadaver heads were imaged again and assessed for evidence of entry through the septum. Results: Soft tissue and osseus structures of the middle ear were readily visualized with a 1.9 mm scope. Success rates for entry into the hypotympanum were high between both endoscope-assisted and traditional procedures, with entry confirmed for 12/13 ears in each group. Conclusions and relevance: Endoscope assistance can facilitate the identification and examination of middle ear structures but does not appear to increase the success rate of entry into the hypotympanum during feline TECA-LBO, as entry through the bony septum was consistently accomplished even without scope-assisted visualization. Alternative benefits to scope assistance may exist, and future studies to elucidate its impact on rates of intraoperative trauma to middle ear structures are indicated.

Answer 93

Objectives: The present study aimed to evaluate the postoperative quality of life (QOL) after surgery for the treatment of intracranial meningioma in cats. Methods: The study included 14 cases that underwent craniotomy from May 2009 to March 2021. Owners were contacted via telephone after a median time of 967 (range 227-4209) days after surgery and surveyed with a specially designed questionnaire that consisted of three domains, subdivided into different items. Physical behaviour, including general condition, food intake, mobility and overall impression, was evaluated from 0, reflecting the worst status, to 10, reflecting the best. The development of preoperative existing clinical signs, seizures and concurrent medication were evaluated individually for each patient. The time span necessary for the improvement of each item was recorded. Finally, satisfaction about the decision for surgery was ranked from 0 to 10. Results: Thirteen questionnaires were completed. Three cats were evaluated twice owing to revision surgery. Owners reported a statistically significant (P <0.001) improvement from immediately after the operation to 240 days after surgery. Preoperative clinical signs resolved in 95% of cases. All questioned owners would opt for surgery again. Conclusions and relevance: QOL after surgery for intracranial meningioma in cats seems encouraging regarding our study. Nevertheless, limitations, such as small sample size, recall bias, lack of a control group and validation of the questionnaire, need to be kept in mind when interpreting the results.

Answer 94

Objectives: The present study aimed to determine the inheritance pattern and genetic cause of congenital radial hemimelia (RH) in cats. Methods: Clinical and genetic analyses were conducted on a Siamese cat family (n = 18), including two siblings with RH. Radiographs were obtained for the affected kittens and echocardiograms of an affected kitten and sire. Whole genome sequencing was completed on the two cases and the parents. Genomic data were compared with the 99 Lives Cat Genome data set of 420 additional domestic cats with whole genome and whole exome sequencing data. Variants were considered as homozygous in the two cases of the siblings with RH and heterozygous in the parents. Candidate variants were genotyped by Sanger sequencing in the extended pedigree. Results: Radiographs of the female kitten revealed bilateral absence of the radii and bowing of the humeri, while the male kitten showed a dysplastic right radius. Echocardiography suggested the female kitten had restrictive cardiomyopathy with a positive left atrial-to-aortic root ratio (LA:Ao = 1.83 cm), whereas hypertrophic cardiomyopathy was more likely in the sire, showing diastolic dysfunction using tissue Doppler imaging (59.06 cm/s). Twenty-two DNA variants were unique and homozygous in the affected kittens and heterozygous in the parents. Seven variants clustered in one chromosomal region, including two frameshift variants in cardiomyopathy associated 5 (CMYA5) and five variants in junction mediating and regulatory protein, P53 cofactor (JMY ), including a missense and an in-frame deletion. Conclusions and relevance: The present study suggested an autosomal recessive mode of inheritance with variable expression for RH in the Siamese cat family. Candidate variants for the phenotype were identified, implicating their roles in bone development. These genes should be considered as potentially causal for other cats with RH. Siamese cat breeders should consider genetically testing their cats for these variants to prevent further dissemination of the suspected variants within the breed.

Answer 95

Objectives: To review long-term outcomes of dogs with acute oropharyngeal stick injuries managed with rigid endoscopy at a UK referral centre. Materials and methods: Retrospective analysis and follow-up with referring veterinary surgeons and owners of patients treated between 2010 and 2020. A medical record search was performed and data regarding signalment, clinical presentation, treatment and long-term outcomes were recorded. Results: Sixty-six dogs with acute oropharyngeal stick injury were identified and 46 (70.0%) of these had endoscopy of the wound. The dogs were of various breeds, ages (median=3 years; range 0.6 to 11 years) and weights (median=20.4 kg; range 7.7 to 38.4 kg) and 58.7% of patients were male. The median time from injury to referral was 1 day (range 2 hours to 7 days). Patients were anaesthetised, and injury tracts were explored using 0° and 30° forward-oblique, 2.7 mm diameter, 18 cm length rigid endoscopes with a corresponding 14.5 French sheath using saline infusion via gravity. All foreign material that could be grasped was removed using forceps. Tracts were flushed with saline and reinspected to confirm removal of all visible foreign material. Out of 40 dogs with long-term follow-up, 38 (95.0%) had no major long-term complications. The remaining two dogs developed cervical abscessation after endoscopy, one of which resolved after repeat endoscopy and the other resolved after open surgery. Clinical significance: Long-term follow-up of dogs with acute oropharyngeal stick injury managed with rigid endoscopy showed an excellent outcome in 95.0% of cases.

Answer 96

Objectives: To describe the surgical technique and evaluate the outcome and complications after coccygeal vertebral fracture repair in dogs using internal fixation. Materials and methods: Medical records and radiography of client-owned dogs were reviewed retrospectively. A lateral approach to the vertebral body was used, and a 1.5 or 1.0 mm plate was applied laterally. Initial follow-up included clinical and radiographic assessment at 6 to 8 weeks postoperatively. Short-term follow-up was assessed by the completion of an adapted functional questionnaire by owners. Results: Four dogs presented with mid-vertebral body fractures. The neurological function of the tail was preserved, and fracture repair was performed in all cases. One dog developed a surgical site infection, which was successfully treated with antimicrobial therapy. One dog experienced prolonged postoperative pain and delayed union. Fracture healing occurred in all patients at the final follow-up. Neither discomfort nor reduced function or mobility of the tails was noticed during the postoperative patient assessment. The questionnaire was completed by all owners with a mean follow-up time of 40 weeks. Excellent outcomes were established from subsequent clinical reviews and owner questionnaires, related to their dog's activity and comfort levels. Clinical significance: Excellent outcomes can be achieved following the repair of coccygeal vertebral fractures in dogs using internal fixation, including a return to normal function of the tail.

Answer 97

Objectives: To quantify the physical activity levels in dogs with cranial cruciate ligament rupture before and after lateral fabellar suture stabilisation surgery. Materials and methods: Seventeen dogs (mean weight, 12.3±5.1 kg) with unilateral cranial cruciate ligament rupture were fitted with an accelerometer for seven consecutive days at four different time points: before surgery (T0), one (T1), three (T3) and six (T6) months after surgery. The total activity and times spent in sedentary activity, light to moderate activity and vigorous activity were recorded by the accelerometer, and preoperative and postoperative data were compared. At all time points, dogs underwent clinical evaluations (lameness score, stifle pain score and thigh circumference) and their owners were asked to respond to questionnaires to subjectively score the physical activity and quality of life of the dogs. Results: At the four time points, the dogs spent between 21.2 and 21.4 hours on sedentary behaviour, 2.3 and 2.5 hours performing light to moderate activity, and 13 to 15 minutes performing vigorous activity. There was no increase in physical activity variables or decrease in sedentary behaviour over time. Lameness scores, pain score and dogs' quality of life improved significantly during the postoperative period. At T6, 17 (100%) of 17 dogs presented no lameness, 16 (94%) of 17 dogs presented no stifle pain, 16 (94%) of 17 owners rated the quality of life as very good and excellent, and 16 (100%) of 16 owners reported a total return to normal activity levels. Clinical significance: The clinical recovery after extracapsular stabilisation of the stifle joint was not associated with a spontaneous increase in physical activity or a decrease in sedentary behaviour.

Answer 98

Mobility impairments associated with musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, affect approximately 200,000 dogs annually and pose a notable challenge to canine health and welfare. Osteoarthritis causes the remodelling of synovial joints, alongside inflammation and impaired mechanical function which can be extremely debilitating. Secondary osteoarthritis commonly affects dogs and can be exacerbated by previous joint abnormalities, such as patellar luxation or cranial cruciate ligament rupture. Although musculoskeletal diseases can affect dogs of any age, the early subtle signs of gait abnormalities are perhaps missed by owners, thus, dogs may be in the latter stages of osteoarthritis progression when they are presented to veterinarians. Dogs showing subtle signs of gait abnormalities must be presented to veterinary practices for acute diagnosis to prevent long-term deterioration. Musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, are commonly diagnosed via visible radiographic changes. However, veterinarians can use a combination of subjective and objective clinical scoring systems, such as clinical metrology instruments and gait assessment in conjunction with radiography to aid their diagnosis and longitudinal monitoring of musculoskeletal diseases. These scoring systems may be more sensitive to earlier signs of mobility impairments in dogs, ultimately, promoting increased canine health and welfare by enabling pain reduction, improvement of muscle strength and preservation of joint function. Current canine mobility scoring systems available to veterinarians will be discussed in turn throughout this review for implementation into clinical practice.

Answer 99

Objective: To describe (1) the surgical anatomy of the accessory lung lobe (ALL) including vasculature and pulmonary ligamentous attachments and (2) lobectomy through a right thoracotomy and median sternotomy. Study design: Cadaveric anatomical study. Animals: Nine adult canine cadavers, free of disease affecting the thoracic cavity and lung parenchyma. Methods: Median sternotomy and right and left lateral thoracotomies were performed to describe and image relevant variations in anatomy using accompanying photographs and thorough voice notes. Consideration for ALL removal via right thoracotomy at the fifth through seventh intercostal spaces and median sternotomy were documented and compared. Results: The median weight of the cadavers was 20.85 kg (6.9-45.5 kg). Variation in the configuration of venous drainage of the ALL was identified. The lateral vein varied in its location and was also observed to combine with the medial vein in one cadaver. The pulmonary ligament attached to the ALL in a caudally pointing apex on the dorsal process of the lobe. Medial and lateral extensions of the ALL parenchyma were found. The ALL was most easily accessed by a right lateral thoracotomy at the sixth intercostal space. Although not optimal, removal of this lung lobe via median sternotomy was feasible. Conclusion: Significant variations were found in the blood supply to the ALL. A right lateral thoracotomy at the sixth intercostal space was preferred for a surgical approach to the ALL. Clinical significance: Surgeons should be aware of several anatomical particularities including the venous drainage, ligamentous attachments, and parenchymal extensions of the ALL.

Answer 100

Objective: To compare postoperative analgesic use and postoperative complications between dogs that received liposomal bupivacaine (LB) during surgical gastrointestinal foreign body (GIFB) removal and those that did not. Study design: Retrospective study. Animals: Two hundred five dogs. Methods: Medical records for all dogs with GIFB removal at the Purdue University Veterinary Hospital between May 2017 and August 2021 were searched. Incomplete records and dogs with less than 2 weeks' veterinary follow up were excluded. Data collected included: patient information, time until surgery, intraoperative findings, surgical data (including perforation at time of surgery, linear vs. solid, enterotomy vs. enterectomy), use of LB (including time and manner of administration), time to extubation after surgery, in-hospital postoperative analgesic use and duration, and postoperative complications. Fentanyl was noted as used/not used, quantified as mean hourly rate over 12 h intervals. All analyses were performed using commercial statistical software with p < .05 as the significance level. Results: Dogs that received LB were heavier (n = 65, median 28.5 kg) than those that did not (n = 140, median 24.4 kg) (p = .005). Postoperative fentanyl use (p < .05 between 13 and 72 h) and hourly rates (p < .05 between 13 and 48 h) were less, and postoperative time in the intensive care unit (ICU) (p < .001) and hospital were shorter (p < .001) in dogs receiving LB. Postoperative wound complications were seen in 7/65 dogs (10.8%, 95% CI = 4.4-21.0%) with LB and 4/140 (2.9%, 95% CI = 0.8-7.2%) without LB (p = .039). Conclusion: Use of LB was associated with reduced postoperative analgesic use, and shortened ICU and hospital stay but also with wound complications.

Answer 101

Objective: To report a surgical technique and outcomes of transiliosacral toggle suture repair to treat feline bilateral sacroiliac luxation/fracture (SILF). Study design: Retrospective study. Animals: Fifteen client-owned cats. Methods: The medical records of cats with bilateral SILF treated using a transiliosacral toggle suture repair were reviewed. Short- and medium-term outcomes were assessed through standard postoperative clinical evaluation and radiographs, including measurements of angle of deviation (AoD), percentage of reduction (PoR), and pelvic canal width ratio (PCWR). Long-term functional follow up was obtained from a questionnaire derived from the Feline Musculoskeletal Pain Index (FMPI). Results: Fifteen cats were enrolled retrospectively, among which 13 survived to discharge. One minor wound complication, treated by secondary intention healing, was encountered. No major complication was reported. Immediately postoperatively, the mean absolute PoR values were 88.1 ± 11.2% and 91 ± 11.6% on the right and left side, respectively. The mean absolute AoD was 3.1 ± 2.8°, and the mean PCWR was 1.24 ± 0.08. The medium-term radiographic follow up at a median of 205 (71-682) days postsurgery revealed the good stability of the repair. Excellent functional outcomes were identified upon the analysis of 12 long-term questionnaires at a median of 365 (119-798) days postsurgery. Conclusion: Anatomic reduction was satisfactory and comparable with previously described techniques with good implant placement documented. Functional outcomes based on FMPI-derived questionnaires were good to excellent in our population. Clinical significance: Transiliosacral toggle suture stabilization of bilateral SILF was associated with good outcomes in cats. Further studies are required to compare biomechanical properties and outcomes between this technique and previously described transiliosacral stabilization.

Answer 102

Objective: To report the clinical outcomes of gastrointestinal surgery using unidirectional barbed sutures in single-layer appositional closure in dogs and cats. Study design: Retrospective and descriptive study. Sample population: Twenty-six client-owned dogs; three client-owned cats. Methods: Medical records of dogs and cats that received gastrointestinal surgery closed with unidirectional barbed sutures were reviewed to collect information on signalment, physical examinations, diagnostics, surgical procedures, and complications. Short- and long-term follow-up information was collected from the medical records, the owners, or the referring veterinarians. Results: Six gastrotomies, 21 enterotomies, and nine enterectomies were closed with a simple continuous pattern with unidirectional barbed glycomer 631 sutures. Nine dogs had multiple surgical sites closed with unidirectional barbed sutures. None of the cases in the study developed leakage, dehiscence, or septic peritonitis during the 14-day short-term follow up. Long-term follow up information was collected for 19 patients. The median long-term follow-up time was 1076 days (range: 20-2179 days). Two dogs had intestinal obstruction due to strictures at the surgical site 20 and 27 days after surgery. Both were resolved with an enterectomy of the original surgical site. Conclusion: Unidirectional barbed suture was not associated with a risk of leakage or dehiscence after gastrointestinal surgery in dogs and cats. However, strictures may develop in the long term. Clinical significance: Unidirectional barbed sutures can be used during gastrointestinal surgery in client-owned dogs and cats. Further investigation of the role of unidirectional barbed sutures leading to abscess, fibrosis, or stricture is necessary.

Answer 103

Objective: To describe the surgical technique for extravesicular, two-layer, side-to-side ureteroneocystostomy combined with tension-relieving techniques (ETSUTT) for feline proximal ureteral obstruction and report clinical outcomes. Study design: Retrospective case series. Animals: Ten privately-owned cats with ureteral obstruction near the ureteropelvic junction (UPJ). Methods: Medical records were retrospectively reviewed for cats with ureteral obstruction close to the UPJ that underwent ETSUTT (2018-2021). The ETSUTT procedure consisted of a modified extravesicular technique (two-layer, side-to-side ureteroneocystostomy) and tension-relieving techniques (renal descensus, ureterocystopexy, and nephrocystopexy). Results: All cats survived through discharge. In all cats, postoperative blood urea nitrogen and creatinine concentrations were decreased, compared with preoperative concentrations. Perioperative complications included ureteral catheter dislodgement (3), transient pollakiuria (2), and dysuria (1), but no specific treatments were required. Urinary tract infection was observed postoperatively in three of the 10 cats. The median follow-up was 648 days (min-max: 86-1229 days). Seven of the 10 cats were alive without recurrent ureteral obstruction at the end of this retrospective study. Conclusion: The ETSUTT procedure was successfully performed without major complications in cats with ureteral obstruction occurring near the UPJ. Use of ETSUTT provided a fair-to-good, long-term prognosis in cats that were otherwise difficult to manage. Clinical significance: This novel procedure, ETSUTT, was feasible, safe, and could be a viable treatment option for feline proximal ureteral obstruction, including the UPJ, especially for obstructions caused by stricture.

Answer 104

Objective: To compare the mechanical properties of suture tape and orthopedic wire cerclage in an ex vivo canine median sternotomy model. Study design: Ex vivo. Animals: Twelve large-breed canine cadaveric sternums. Methods: Median sternotomies were performed, leaving the manubrium intact. The specimens were randomly assigned to group W (20-gauge stainless steel orthopedic wire cerclage in a figure-of-eight pattern) or group ST (suture tape in a figure-of-eight pattern). Each specimen was laterally distracted until failure using an electrodynamic materials-testing system. Results: No differences were observed for displacement, yield load, maximum load, implant failure between the groups. The orthopedic wire construct was stiffer than the suture tape construct. Conclusion: Suture tape was biomechanically similar to orthopedic wire cerclage for sternotomy closure in dogs, although wire constructs were stiffer. Clinical significance: Suture tape may represent an alternative to cerclage wire for sternotomy closure in dogs. Additional studies evaluating its clinical use are needed.

Answer 105

Objective: To describe two techniques for nephrocystostomy (NCT) in cats. Study design: Experimental study. Animals: Twelve, adult, purpose-bred, cats. Methods: A simple NCT (n = 3) or bladder cuff NCT (n = 9) was performed in the right or left kidneys. For simple NCT, an 8F catheter was placed through the caudal pole into the renal pelvis and the bladder was sutured around the catheter. For bladder cuff NCT, a 6 mm defect was removed from the caudal pole and a cuff of bladder mucosa was advanced and sutured into the renal pelvis. A 10F catheter was placed through the defect into the renal pelvis and the bladder wall was sutured around the catheter. Catheters were removed 41-118 days post-surgery. Computed tomography (CT) was performed 25 days after catheter removal for the simple NCT and 30 (n = 6) and 90 (n = 3) days after catheter removal for bladder cuff NCT. Histological evaluation of the nephrocystostomy site was performed. Results: All simple NCTs became obstructed after catheter removal. All bladder cuff NCTs were patent, and CT revealed contrast flow into the bladder. Hematuria, clot-associated urethral obstruction, catheter dislodgement, and bladder infection occurred variably after surgery. Histological findings consisted of smooth epithelialization of the NCT and degenerative changes in the caudal pole of the kidney. Conclusion: Bladder cuff NCT was feasible in normal cats and remained patent for 90 days. Methods to limit nephrostomy track hemorrhage should be investigated. Degenerative changes may be related to vascular impairment from the bladder cuff sutures. Clinical significance: Complete ureteral bypass was possible in cats using only native tissues.

Answer 106

Objective: To report the incidence of metastatic calcification in cats with renal failure presenting for renal transplantation, and to determine if metastatic calcification detected prior to renal transplantation is associated with complication rates and patient survival. Study design: Retrospective case series. Sample population: Seventy-four cats. Methods: In imaging studies, 178 feline renal transplant recipients from 1998 to 2020 were evaluated for metastatic calcification. Demographic, clinicopathological data, intraoperative complications, postoperative complications, need for hemodialysis, and survival times were recorded. Exclusion criteria were cats lacking imaging reports and cats with gastric, renal, or tracheal/bronchial calcification alone. Univariable and multivariable analyses were performed to determine variables that were independently associated with survival. Kaplan-Meier analysis was used to generate survival plots and estimate median survival times with a 95% confidence interval (CI). Results: Seventy four of 178 cats met the inclusion criteria. Fifteen of 74 (20.3%) cats had metastatic calcification prior to renal transplantation. Twelve of 74 (16.2%) cats developed calcification following transplantation, and 47 of 74 (63.5%) cats had no calcification during the study period. Median follow-up time was 472 days, with a range of 0-1825 days. Cats with pretransplant calcification had shorter median survival times (147 days) than cats without calcification (646 days) (p = .0013). Metastatic calcification pretransplant was associated with an increased risk of death by 240% (95% CI, 1.22-4.71). Conclusion: Metastatic calcification in renal transplant cats is a negative prognostic indicator and is associated with decreased survival times. Clinical significance: These findings may help guide therapeutic recommendations and owner expectations in cats undergoing renal transplantation.

Answer 107

Objective: To compare complications between a modified incisional gastropexy (MIG) technique and standard incisional gastropexy (SIG). Animals: 347 client-owned dogs. Procedures: Dogs that had undergone SIG or MIG from March 2005 through April 2019 were identified through a medical record search of the University of Missouri Veterinary Health Center. The MIG technique is identical to SIG except 2 additional simple interrupted sutures are added, 1 cranial and 1 caudal to the continuous suture line, going full thickness into the stomach to ensure engagement of submucosa. Medical record information was used to identify intraoperative, postoperative, and short-term complications, and telephone or email communication to pet owners and/or referring veterinarians was used to identify complications (short-term and long-term) after discontinuance of care at the University of Missouri Veterinary Health Center. Intraoperative, postoperative, short-term, and long-term complications were analyzed in aggregate within 6 matched groupings: (1) gastropexy for gastric dilatation-volvulus, (2) prophylactic gastropexy without other procedures, (3) gastropexy with ovariohysterectomy, (4) gastropexy with castration, (5) gastropexy with splenectomy, and (6) gastropexy with celiotomy other than splenectomy. Overall rates of complications potentially attributed to gastropexy were compared between SIG and MIG using the Fisher exact test. Overall rates of complications not attributed to gastropexy were compared between SIG and MIG using the χ2 test. Results: There were no significant differences in overall complication rates between SIG and MIG. Clinical relevance: Surgeons who feel that engagement of gastric submucosa is important for gastropexy success may use the MIG technique with minimal fear of complications. However, superiority of one technique over the other cannot be determined on the basis of this study.

Answer 108

Objective: To compare outcomes and short-term complications of dogs with laryngeal paralysis treated with unilateral arytenoid lateralization performed on an outpatient versus inpatient basis. Animals: 44 client-owned dogs. Procedures: Medical records were retrospectively reviewed to identify dogs that underwent unilateral arytenoid lateralization for the treatment of laryngeal paralysis between 2018 and 2022. Signalment, surgical technique, anesthesia time, comorbidities, laryngeal examination, concurrent procedures, use of prokinetics and sedatives, episodes of vomiting, episodes of regurgitation, duration of hospitalization, postoperative complications, anxiety scores, and pain scores were recorded. Variables were compared between dogs and grouped by outpatient or inpatient management. Results: The overall complication rate was 22.7% (10/44), with 35% (7/20) being in the inpatient group and 12.5% (3/24) being in the outpatient group. The overall mortality rate was 6.8% (3/44). The overall morbidity for hospitalized patients versus those undergoing and outpatient procedure was 5% (1/20) and 4.2% (1/24), respectively. There was no significant difference between overall rate of complications and mortality rates between the inpatient and outpatient groups. Clinical relevance: Results suggested that outpatient management of dogs with laryngeal paralysis treated with elective unilateral arytenoid lateralization is an appropriate method of postoperative management with no difference in complication or mortality rates. Further prospective studies with standardized surgical, sedative, and antiemetic protocols are warranted to evaluate more definitely.

Answer 109

Objective: Describe surgical guidelines for a new technique to correct stenotic nares in brachycephalic cats. Animals: 8 client-owned brachycephalic cats with stenotic nares between April 2017 and July 2022. Procedures: 8 brachycephalic cats with severe stenotic nares presented to the Angell Animal Medical Center with the patient age ranging from 2 years to 9 years of age. Surgical correction was performed on each cat with the combined use of the "Alar Fold Lift-Up" and "Sulcus Pull-Down" techniques. Results: Successful correction of the stenotic nares was achieved, enabling each cat to breathe normally. Clinical relevance: The combined use of the "Alar Fold Lift-Up" and "Sulcus Pull-Down" techniques is simple to perform on an outpatient basis. Surgery is restricted to the adjacent skin and does not require the surgical alteration of the external nose or nares. Long-term follow-up indicates the procedure is effective in improving nasal breathing in each cat.

Answer 110

Objective: To report the presence of urolithiasis in dogs long-term after gradual attenuation of congenital extrahepatic portosystemic shunts (cEHPSS). Animals: 25 client-owned dogs that underwent gradual attenuation of a cEHPSS, of which 19 had a closed cEHPSS and 6 developed multiple acquired portosystemic shunts (MAPSS) following surgery. Procedures: A retrospective study with prospective follow-up was performed. Dogs that underwent cEHPSS surgery and had their postoperative cEHPSS status determined by transsplenic portal scintigraphy or CT angiography 3 months postoperatively were prospectively contacted and invited for a long-term follow-up visit (a minimum of 6 months postoperatively). Retrospective data were collected, and during the prospective follow-up visit a thorough history, blood tests and urinalysis, and ultrasonography of the urinary tract were performed to assess the presence of urinary signs and urolithiasis. Results: Of 25 included dogs, 1 of 19 (5%) dogs with closed cEHPSS and 4 of 6 (67%) dogs with MAPSS had urolithiasis at long-term follow-up. Three (50%) dogs with MAPSS developed new uroliths. Long-term, dogs with closed cEHPSS that initially presented with and without urolithiasis had significantly less urolithiasis compared to dogs with MAPSS (P = .013 and P = .010, respectively). In the 4 dogs with closed cEHPSS that initially presented with nephrolithiasis, nephroliths became smaller or were no longer visible at the long-term follow-up visit. Clinical relevance: Dogs that developed MAPSS following cEHPSS surgery are at greater risk of urolithiasis compared to those with closed cEHPSS. Furthermore, ammonium urate uroliths might dissolve if portosystemic shunting ceases to exist.

Answer 111

Objective: To report the complication rate of dogs undergoing oral oncological surgery when using a bone-cutting piezoelectric unit for osteotomies. Clinical presentation and procedures: Retrospective cohort evaluation of medical records from 2012 through 2022 for canine patients that underwent mandibulectomy or maxillectomy for the treatment of oral neoplasia at the Companion Animal Hospital at Cornell University. Cases were included if osteotomy was performed using a piezoelectric unit. Medical records were then reviewed for documentation of intraoperative hemorrhage and administration of blood products. Results: 41 maxillectomies and 57 mandibulectomies met the inclusion criteria (98 in total). Only 1 (1.02%) case was associated with excessive surgical bleeding requiring administration of blood products. Clinical relevance: Results of this study show that intraoperative hemorrhage requiring the use of blood products during or immediately after a mandibulectomy or maxillectomy is rare when using a piezoelectric unit to perform osteotomies, and is substantially lower than that previously reported when using oscillating saws or other bone-cutting devices for maxillectomies.

Answer 112

Objective: To compare the acute strength (failure load and work to failure) of standard incisional gastropexy (SIG) and modified incisional gastropexy (MIG). Animals: 37 pig cadavers. Procedures: Stomachs and right abdominal walls were harvested from pigs euthanized for reasons unrelated to this study. The tissues were stored in lactated Ringer's solution overnight in a 5 °C cooler. Matching body wall and stomach tissue pairs were randomized and divided into 2 groups, on which either SIG or MIG was performed the following day. The MIG technique was identical to SIG except 2 additional simple interrupted sutures, 1 cranial and 1 caudal to the continuous suture line, were placed full thickness into the stomach to ensure engagement of the submucosa. After gastropexy, the samples underwent biomechanical testing. Information regarding change in position and load was generated by the MTESTQuattro software. Mode of failure was examined after the procedure was complete. Results: The MIG had higher failure load and work to failure compared to SIG. All failures were caused by gastric tissue tearing. Clinical relevance: The MIG is biomechanically superior to SIG and may provide more security than SIG during healing. However, clinical study is needed to ascertain if there is a difference in gastropexy failure and complications between these 2 techniques.

Answer 113

Objectives: The present study aimed to evaluate the inter-observer reliability of three feline pain scales commonly used in clinical practice. Methods: Twenty cats undergoing elective neutering surgery were assessed both pre- and postoperatively by three independent assessors (a board-certified anaesthetist, a veterinary anaesthesia nurse and a final-year veterinary student) using three different pain scales: the Glasgow Feline Composite Measure Pain Scale (CMPS - Feline), the Colorado State University Feline Acute Pain Scale (CSU - FAPS) and the Feline Grimace Scale (FGS). Reliability statistics was used to evaluate the level of agreement between assessors. Results: Twenty-seven groups of paired observations were evaluated, of which 16 (59%) showed fair agreement, eight (30%) showed none to slight agreement and the remaining three (11%) showed moderate agreement based on Cohen's weighted kappa statistics. Based on Cronbach's alpha statistics, 12 (44%) of the 27 groups of observations showed moderate reliability, 12 (44%) showed poor reliability and the remaining three (11%) showed good reliability. No scale was superior to the others in terms of inter-rater reliability (P = 0.179); however, the pair composed of the final-year veterinary student and anaesthesia nurse showed better agreement than the two other pairs of assessors, both of which included the board-certified anaesthetist (P = 0.015). Conclusions and relevance: Despite the usefulness of behavioural pain scales as clinical tools, their users should bear in mind their limitations, particularly the intrinsic subjectivity and potential variability of outcome between assessors with different backgrounds and level of expertise. Keywords: Behavioural pain scale; acute pain; inter-observer reliability; postoperative pain.

Answer 114

Objectives: The present study aimed to document the use of the wound infusion catheter (WIC) following a variety of surgical procedures in cats, investigating complications and risk factors associated with catheter placement or local anaesthetic (LA) administration. Methods: A retrospective, multicentric study was performed. Medical databases of eight veterinary referral hospitals from 2010 to 2021 were searched to identify records of cats where WICs were used. Information regarding signalment, type of surgery, size and type of WIC placed, and LA protocol used, as well as postoperative complications, were retrieved. Results: One hundred and sixty-six cases fulfilled the inclusion criteria. Feline injection site sarcoma resection was the most common surgery. Overall complications were identified in 22/166 cats (13.2%). Thirteen cats (7.8%) experienced wound-related complications, whereas nine cats (5.4%) experienced drug-delivery complications. The only factor associated with an increased risk of complications was the amount of a single dose of LA delivered through the catheter (P <0.001). An amount higher than 2.5 ml of LA delivered at each administration was associated with an increased risk of complications. All complications were minor and self-limiting. Conclusions and relevance: WICs were used for a large variety of surgical procedures with different protocols of LA administration as part of a multimodal analgesic plan in cats. The risk of complications was relatively low and self-limiting, suggesting its safe use in cats. Further prospective studies are required to evaluate efficacy of postoperative analgesia and to determine the suitable protocol for WIC handling and maintenance.

Answer 115

Objectives: The aim of the present study was to report clinical findings, surgical complications and outcomes for previously hoarded cats treated surgically for otitis media-interna (OMI) and to investigate the risk factors for complications and poor outcomes. Methods: A retrospective study was conducted of 58 cats from an institutional hoarding environment that underwent ventral bulla osteotomy (VBO). Results: Inappetence was uncommon at presentation (9/58, 16%) compared with pruritus/alopecia (50%), nasopharyngeal signs (45%), otitis externa (OE) (79%) and otitis interna (OI) (ataxia ± head tilt/head excursions) in 40%. Purulent aural discharge occurred in 36% and polyps in 26%. The tympanic bulla wall was moderately or severely thickened radiographically in 38/108 (35%) ears. Cultures were positive for Streptococcus equi subspecies zooepidemicus in 26/48 (54%) cats. Of the 58 cats, 40 (69%) had complications after the first VBO and 19/30 (63%) after the second. Of 101 complications, 56 (55%), from 27/88 (31%) surgeries, were considered serious, including life-threatening perioperative complications in seven, OI in eight, prolonged anorexia in six and worsening of pruritus/alopecia in nine cases. Three cats developed xerostomia (dry mouth) after the second VBO. Pruritus/alopecia, nasopharyngeal signs, OE and purulent aural discharge resolved in a statistically significant proportion of cats but persisted in some. Full resolution of OI was uncommon. OI preoperatively, and surgery performed by a generalist (vs specialist) surgeon, were risk factors for OE at recheck (OI: odds ratio [OR] 4.35; 95% confidence interval [CI] 1.21-15.70; P = 0.02; surgery: OR 3.64; 95% CI 1.03-12.87; P = 0.045). No other prognostic indicators were identified. No variables tested were significantly associated with risk of serious complications or euthanasia. Conclusions and relevance: Surgical management of chronic OMI was successful in most cases but was not benign and not always beneficial. The analysis was unable to identify clinically helpful outcome predictors. Optimal management of chronic feline OMI remains a challenge, particularly for animal shelters. Less invasive approaches and chronic medical management require further investigation. Keywords: Otitis media; Streptococcus equi subspecies zooepidemicus; animal hoarding; complications; otitis interna; outcomes; surgery; ventral bulla osteotomy.

Answer 116

Objectives: The aim of the present study was to describe the distribution of gastrointestinal histopathology findings associated with gastrointestinal obstructions secondary to trichobezoar formation in cats. Methods: A total of 100 surgical gastrointestinal biopsies were obtained from 44 cats with gastrointestinal obstructions secondary to a trichobezoar. Medical records, including signalment, type and duration of clinical signs, surgical reports and histopathologic analysis, were reviewed for each cat. Results: Biopsies taken near the site of the trichobezoar were more likely to show neutrophilic inflammation and mucosal erosion/ulceration compared with biopsies taken elsewhere in the small intestine. Lymphoplasmacytic and mixed lymphocytic and eosinophilic populations were the most common histopathologic findings from all biopsies followed by alimentary small cell lymphoma. Biopsy samples were more likely to represent a diagnosis of alimentary lymphoma in cats older than 10 years. Conclusions and relevance: Gastrointestinal biopsies taken at the time of surgery in cats with trichobezoar obstructions may represent an important diagnostic tool for further evaluation of potential feline chronic enteropathy. Biopsies taken at the site of the obstruction should be interpreted cautiously as the presence of a trichobezoar may induce an acute inflammatory reaction. The resultant histologic interpretation at this site may not represent the chronic state of the intestinal mucosa, supporting the utility of obtaining multiple biopsies orad and aborad to the obstruction.

Answer 117

Objectives: This study evaluated success rates of surgical treatment of head and neck abscesses and draining tracts for suspected migrating vegetal foreign body and oropharyngeal penetrating injuries, and compared the outcomes according to whether a vegetal foreign body was identified in preoperative computed tomography (CT) examination. Materials and methods: This retrospective study involved 39 dogs that underwent CT and subsequent surgical exploration of abscesses and/or draining tracts in the head and neck, in a single institution between 2010 and 2021. Recorded data included signalment, history, physical examination, CT and surgical findings. The postoperative follow-up period was at least 8 months. Cases were classified according to whether a foreign body was identified on CT or was only suspected because of the presence of cavities and/or draining tracts on CT. Results: A vegetal foreign body was identified on CT in 11 of 39 cases and later confirmed at surgery in 10 cases. In 28 of 39 cases, a vegetal foreign body was not identified on CT, but in seven of these 28 cases it was found at surgery. Resolution of clinical signs was achieved in 11 of 11 cases when a vegetal foreign body was identified on CT and in 26 of 28 cases without a foreign body identified on CT. Two cases of recurrence were observed in animals in which no foreign body was detected. Clinical significance: In this population of dogs undergoing surgery after preoperative CT scan, we observed resolution of clinical signs after a single surgical procedure in 95% of the cases. All animals in which a foreign body was identified were cured.

Answer 118

Objective: The aim of this study was to describe the use of a procedure-specific fixation method for tibial tuberosity transposition and report clinical outcome. Study design: This is a multi-institutional case series, evaluating 37 cases that were treated surgically for medial patellar luxation (MPL) and in which the tibial tuberosity transposition (TTT) was performed using the Rapid Luxation Plating System (RLPS). Surgical technique, implants, clinical outcome, and complications are reported. Results: Surgery was successfully performed in dogs weighing 2.5 to 36.2 kg. Postoperative minor complications occurred in 13 cases (35%) and major complications occurred in 3 cases (8%). No implant-related complications or tibial tuberosity avulsions or fractures were seen. Outcome related to surgery was good or excellent in all cases. Conclusion: The RLPS for TTT provides a feasible technique in a large range of patients with MPL and lowers the occurrence of implant-related complications and tibial tuberosity avulsion or fracture.

Answer 119

Objectives: The aim of this study was to define landmarks of the intermetatarsal channel of the dorsal pedal artery and to assess whether damage to the dorsal pedal artery during metatarsal screw placement in dogs undergoing pan- and partial-tarsal arthrodesis (PanTA/ParTA) could be a mechanism in the development of plantar necrosis. Study design: This study was divided in to two parts: (1) ex-vivo anatomical study: 19 canine cadavers, (2) retrospective clinical study: 39 dogs. Cadaveric dissection documented the mean intermetatarsal channel position. Metatarsal screw position was evaluated on postoperative radiographs of dogs after PanTA or ParTA. Screw position, arthrodesis type and surgical approach were assessed for their impact on complications, including plantar necrosis. Results: The mean proximal and distal extent of the intermetatarsal channel lies between 4.3% ± 1.9 and 22.8% ± 2.9 the length of metatarsal III (MTIII) respectively. The intermetatarsal channel lies within the most proximal 25% of MTIII in 95% of cases. At least one screw risked damaging the mean intermetatarsal channel position in 92% of dogs; 8% of these dogs went on to develop plantar necrosis. The mean screw position did not differ between ParTA cases with or without plantar necrosis (p > 0.05). Conclusion: Violation of the intermetatarsal channel is possible during metatarsal screw placement. Care should be taken when placing screws in the proximal 25% of the metatarsals, specifically avoiding exiting dorsally between MTII and MTIII and across the distal region of the intermetatarsal channel, where the perforating metatarsal artery passes interosseously, as damage may contribute to the aetiology of plantar necrosis.

Answer 120

Objective: The aim of this study was to compare the interfragmentary compressive force and area of compression generated by cortical screws inserted as either a lag screw or position screw in simulated lateral humeral condylar fractures. Study design: Ex vivo biomechanical study. Materials and methods: Thirteen pairs of cadaveric humeri from skeletally mature Merinos with simulated lateral humeral condylar fractures were used. Pressure sensitive film was inserted into the interfragmentary interface prior to fracture reduction with fragment forceps. A cortical screw was inserted as a lag screw or a position screw and tightened to 1.8Nm. Interfragmentary compression and area of compression were quantified and compared between the two treatments groups at three time points. Results: After fracture reduction using fragment forceps (Time point 1: T1), there was no significant difference in interfragmentary compression and area of compression between the two treatments. A combination of fragment forceps and a cortical screw inserted as a lag screw (Time point 2: T2) produced significantly greater interfragmentary compression and area of compression compared with the same screw inserted as a positional screw. After removal of the fragment forceps, leaving only the cortical screw (Time point 3: T3), both the interfragmentary compression and area of compression remain significantly greater in the lag screw group. Conclusion: Lag screws generate a greater force of compression and area of compression compared with position screws in this mature ovine humeral condylar fracture model.

Answer 121

Objective: The main aim of this study is to compare the impact of six proximal tibial osteotomies on the geometry and alignment of tibias with and without excessive tibial plateau angle (TPA). Study design: Mediolateral radiographs of 30 canine tibias were divided into three groups (n = 10/group): moderate TPA (≤34 degrees), severe TPA (34.1-44 degrees) and extreme TPA (>44 degrees). Six proximal tibial osteotomies were simulated on each tibia using orthopaedic planning software: cranial closing wedge ostectomy (CCWO), modified CCWO (mCCWO), isosceles CCWO (iCCWO), neutral isosceles CCWO (niCCWO), tibial plateau levelling osteotomy with CCWO (TPLO/CCWO) and coplanar centre of rotation of angulation-based levelling osteotomy (coCBLO). All tibias were reduced to a standard target TPA. Pre- and postoperative measurements were obtained for each virtual correction. Compared outcome measures included tibial long axis shift (TLAS), cranial tibial tuberosity shift (cTTS), distal tibial tuberosity shift (dTTS), tibial shortening and osteotomy overlap. Results: Across all TPA groups, TPLO/CCWO had the lowest mean TLAS (1.4 mm) and dTTS (6.8 mm); coCBLO had the largest TLAS (6.5 mm) and cTTS (13.1 mm); CCWO had the largest dTTS (29.5 mm). CCWO had the largest degree of tibial shortening of 6.5 mm, while mCCWO, niCCWO and coCBLO resulted in minimal tibial lengthening (1.8-3.0 mm). These trends were generally conserved across different TPA groups. All findings had a p-value less than 0.05. Conclusion: mCCWO balances moderate alterations to tibial geometry while preserving osteotomy overlap. The TPLO/CCWO has the least effect on tibial morphology alteration, whereas the coCBLO results in the largest alteration.

Answer 122

This article, as part of the Currents in One Health series, reviews the current state of diagnostics for synovial sepsis. Synovial sepsis is a condition that affects veterinary and human medicine and requires coordinated efforts from both parties, as well as environmental considerations to accurately diagnose and preserve effective treatments. The article discusses best practices to identify the causative agent in septic synovitis, trends in bacterial identification and antimicrobial resistance patterns across common bacterial species, and a one-health perspective to optimize diagnostics across species. Antimicrobial resistance is a challenge facing both human and veterinary medicine and requires mindful and attentive prescribing to reduce the development of antimicrobial resistance and preserve antimicrobials for future application. The current standard of care for bacterial identification in veterinary practice is culture and antimicrobial susceptibility; however, positive culture rates from synovial sepsis cases often remain < 50%. Recent developments in advanced bacterial identification present opportunities for improved bacterial identification in synovial sepsis. Increased bacterial isolation will also help guide empirical antimicrobial therapy. Utilizing information and recommendations from both the human and veterinary literature will improve timely and accurate bacterial identification and therefore rapid and effective treatment of synovial sepsis across species and limit the development of antimicrobial resistance.

Answer 123

Objective: To report the outcome of locally administered antibiotic-impregnated poloxamer 407 (P407) hydrogel in dogs diagnosed with orthopedic surgical site infections (SSIs) and to identify risk factors for treatment failure. Animals: 34 client-owned dogs diagnosed with an orthopedic surgical site infection treated with local antibiotic-impregnated P407 hydrogel. Procedures: Medical records were reviewed of dogs receiving antibiotic-impregnated P407 hydrogel for an active orthopedic SSI between March 2018 and December 2020. The rate of successful infection clearance was calculated. Risk factors for failed treatment were evaluated with statistical analyses. Results: 34 dogs met the inclusion criteria. Vancomycin-impregnated P407 hydrogel (20 mg/mL) was implanted in all dogs. The rate of infection clearance was 77%. Each unit increase in the number of surgeries performed at a site before gel implantation decrease the chance of successful infection clearance by 25% (P = .005; unit OR, 0.25; 95% CI, 0.08 to 0.81). Presence of multidrug or methicillin resistance increased risk for treatment failure by 7.69 times (P = .042; OR, 0.13; 95% CI, 0.01 to 1.14). No adverse events related to gel administration were seen. Clinical relevance: Treatment outcomes were negatively impacted by the presence of multidrug or methicillin resistance and by an increased number of surgeries before gel implantation. Local administration of antibiotic-impregnated P407 hydrogel had a high success rate with no adverse effects in this population. Local antibiotic gel administration may improve treatment outcomes in dogs with complicated SSI.

Answer 124

Objective: To evaluate the short- and long-term outcomes of dogs undergoing surgical ligation for a left-to-right shunting patent ductus arteriosus (PDA), identify risk factors for intraoperative hemorrhage and intra- and postoperative complications, and report overall mortality rates. Animals: 417 client-owned dogs undergoing surgical ligation for a left-to-right shunting PDA between January 2010 and January 2020. Procedures: Data recorded included patient signalment, echocardiogram findings, intraoperative complications and mortality, postoperative complications, and short- and long-term outcomes. Results: There was no association between age and risk of intraoperative hemorrhage (P = .7), weight and intraoperative hemorrhage (P = .96), or increasing left atrium-to-aortic (LA:Ao) ratio and intraoperative hemorrhage (P = .08). Intraoperative hemorrhage occurred in 10.8% of patients. Intraoperative mortality was 2%. Ninety-five percent of dogs experiencing intraoperative hemorrhage survived to discharge. Survival to discharge was 97%. One- and 5-year survival rates were 96.4% and 87%, respectively. Clinical relevance: Surgical ligation for a left-to-right shunting PDA is recommended due to the good long-term prognosis. Certain preoperative factors such as age, weight, and the presence and degree of mitral valve regurgitation had no detectable association with risks of intraoperative hemorrhage and, therefore, should not preclude surgical treatment for a left-to-right shunting PDA. Future studies are needed to further assess the association between increasing LA:Ao ratio and risk of intraoperative hemorrhage.

Answer 125

Case series summary: Salivary gland adenocarcinoma, of major or minor salivary gland origin, is an uncommon tumor in cats. This article describes the clinical features, morbidity and survival rates of four cats with salivary gland adenocarcinoma arising from minor salivary gland tissue. Medical records from a private multicenter dentistry and oral surgery practice were reviewed for the period between 2007 and 2021. Four cats were included in this retrospective case series study, with oral masses on either the right or left caudal mandibular labial buccal mucosa. The inclusion criteria included a diagnosis of salivary gland adenocarcinoma in an anatomical location with lack of involvement of a major salivary gland, complete medical history and a follow-up of at least 6 months. The age range of the cats was 9-15 years; three of the cats were castrated males and one was a spayed female. Curative intent surgery was performed in three cats, whereas palliative surgery (debulking) owing to extensive soft tissue invasion was performed in one cat. Survival times were in the range of 210-1730 (mean 787) days. All four cats were euthanized owing to local recurrence and decreased quality of life, regardless of treatment modality. Relevance and novel information: There are limited documented studies reporting the prevalence of salivary gland neoplasia affecting minor disseminated glands in the oral cavity of feline patients. Salivary gland adenocarcinoma should be a differential in cats presenting with caudal labial masses. Surgical resection has been the recommended treatment for salivary gland neoplasia of major salivary gland origin. According to this current case series, we propose that early aggressive surgical treatment with wide surgical margins should be performed for cats with salivary gland adenocarcinoma of minor salivary gland origin. Surgery increased the quality and duration of life; however, each patient was euthanized owing to local recurrence and morbidity.

Answer 126

Objective: To describe the conservative management and outcome of gastrointestinal metallic sharp-pointed straight foreign bodies in dogs and cats. Materials and methods: Clinical records of dogs and cats presented to a university teaching hospital between 2003 and 2021 with gastrointestinal metallic sharp-pointed straight foreign bodies (e.g. needles, pins, nails) were reviewed. Conservative management was defined as leaving the foreign body in situ. Cases were excluded if the foreign body was identified outside of the gastrointestinal tract (including oropharynx and oesophagus) or if it was removed by endoscopy or surgery as the first treatment choice. Patient signalment, presenting complaint, foreign body location, treatment, complications, gastrointestinal transit time, length of hospitalisation and outcome were recorded. Results: A total of 17 cases (13 dogs and four cats) were included in the study, being treated with primary conservative therapeutic approach (11) or following failure of endoscopy (two), surgery (three) or both (one). Clinical signs associated with the foreign body were reported in three (17.6%) cases. Conservative management was successful in 15 (88.2%) cases, with no complications reported. Patients were clinically and radiographically monitored with variable supportive care. In two (11.8%) cases, surgery was subsequently performed as the foreign body failed to progress on repeated radiographs after 24 hours. Mean foreign body gastrointestinal transit time for patients treated conservatively was 59.2 (±31.4) hours. All patients survived to discharge. Clinical significance: Conservative management is a treatment option for clinically stable cats and dogs with metallic sharp-pointed straight gastrointestinal foreign bodies in the absence of perforation.

Answer 127

Objective: To evaluate the feasibility of laparoscopic vertical sleeve gastrectomy (LVSG) in feline cadavers using endoscopic stapling equipment and report clinical outcomes in two live feline subjects. Study design: Cadaveric study and experimental case series. Animals: Ten feline cadavers; two feline subjects. Methods: LVSG technique was refined on feline cadavers and included retraction of the liver, dissection of the stomach, assessment of proper location for gastrectomy via stapling, and leak testing. Appropriateness of gastrectomy, gastrectomy %, surgical times and complications were recorded. The procedure was performed on two live feline subjects, and they were followed for 4 months to report surgical complications. Results: LVSG was completed in 9/10 cadavers and both live patients. Stenosis at the incisura was recorded in 2/9 cadavers. No obvious leaks were seen in the 8 cadavers that were tested or either live patient. The mean surgical time for all cadaver procedures and live patients was 110.4 and 115 minutes, respectively. Mean weight of resected cadaver stomach was 10 g and the mean % of the total stomach weight resected was 27.6%. No intra- or postoperative surgical complications occurred in the live subjects. Conclusion: LVSG technique appears feasible and safe for use in live patients. Clinical relevance: This LVSG technique may be safely used for partial gastric resection in cats. Further studies are necessary to determine if it is effective at reversing the effects of obesity and diabetes in this population.

Answer 128

Objective: To evaluate custom 3D printed laparoscopic cannulas (3DPC) in a feline cadaveric abdominal surgery model and report their use in two live feline subjects. Study design: Experimental cadaver study, live subject case series. Animals: Ten feline cadavers; two feline subjects. Methods: Custom 3DPCs were initially modeled in a PLA filament material and then created in an autoclavable dental resin for use in live patients. The surgery time, number of surgical collisions and cannula complications were recorded during cadaver procedures before and after use of 3DPCs. Cannula complications were recorded during live procedures and patients were followed to suture removal to record any incisional complications. Results: There was a significant reduction in mean surgical time (125.6 vs. 95.2 min, p = 0.03), mean number of instrument collisions (6.8 vs. 2.6, p = 0.03), and mean number of cannula complications (10 vs. 2.2, p = 0.03) with the use of only 3DPCs during the procedure. During the live procedures the use of the 3DPCs was successful and no postoperative complications occurred at the incision sites. Conclusion: The use of customized 3DPCs may improve surgical dexterity and decrease complications in advanced procedures and was not associated with any clinical complications in two cats. The use of 3DPCs in veterinary medicine may allow for wider practice of laparoscopic techniques in small animals.

Answer 129

Objective: To describe and evaluate minimally invasive repair of acetabular fractures in dogs using plates contoured to 3D-printed hemipelvic models. Study design: Ex vivo feasibility study and case report. Sample population: Adult canine cadavers (n = 5); 8 year old male neutered Chihuahua. Methods: Bone plates were contoured to 3D printed hemipelvic models derived from computed tomographic scans of each dog. In cadavers, acetabular, ischial, and pubic osteotomies were performed. A small craniolateral approach to the ilial body and a caudal approach to the ischium were made and connected through epiperiosteal tunnels. Under fluoroscopic guidance, fractures were reduced, and precontoured bone plates were applied with locking screws. Postoperative computed tomographic images were used to assess fracture gaps, step defects, and pelvic angulation. Cadavers were dissected for subjective assessment of sciatic nerve injury. Radiographic and clinical follow up was acquired for the clinical case. Results: Small fracture gaps (<2 mm) and step defects (<1 mm), low pelvic angulation (<5°), and minimal (none n = 4 and mild n = 1) sciatic nerve injuries were observed in cadaver testing. There was slight (~1 mm) medial displacement of the pubic segment and good functional outcome for the clinical case, with radiographic healing documented at 3 months postoperatively. Conclusion: Minimally invasive acetabular fracture repair in dogs with the aid of 3D printing was feasible and accurate. Clinical significance: Minimally invasive repair techniques assisted by 3D printing may be applicable for acetabular fractures in dogs. The technique should be evaluated further before routine use can be recommended.

Answer 130

Objectives: To report the short-term clinical outcome and complications in dogs that underwent surgical repair of femoral capital physeal or neck fractures via fluoroscopic-guided percutaneous pinning (FGPP). Study design: Retrospective case series. Animals: Client owned dogs (n = 11) with femoral capital physeal or neck fractures (n = 13). Methods: Records (July 2018-July 2021) of dogs that underwent surgery for femoral capital physeal or neck fracture repair with FGPP from two hospitals were reviewed. Data collected included signalment, age, weight, preoperative lameness severity, fracture factors (etiology, Salter-Harris classification, time from injury to surgery, radiographic displacement), surgical factors (surgery time, number/size of implants, reduction quality) and outcome (follow-up examination findings, radiographic findings, complications). Results: Most fractures (11/13) occurred secondary to trauma. The median time from injury to surgery was 5.5 days. There was mild radiographic displacement preoperatively in 10/13 fractures. Satisfactory fracture healing and limb function was achieved in 10/13 femurs. Complications occurred in 5/11 cases and included intra-articular implants, implant failure/nonunion, implant migration (2), and malunion. Of these five complications, two resolved with implant removal, and a salvage procedure was recommended in the remaining cases. Of the three cases requiring salvage procedures, two originally presented with radiographic evidence of fracture chronicity. Conclusions: FGPP can be used to successfully treat femoral head and neck fractures with appropriate case selection and precise surgical technique.

Answer 131

Objective: To report outcomes of thoracoscopic (TL) and thoracoscopic-assisted lung lobectomy (TAL) for treatment of non-neoplastic pulmonary consolidation (PC) in dogs. Study design: Retrospective case series. Animals: Twelve client-owned dogs. Methods: The medical records of 12 dogs that underwent TL or TAL for PC at 3 veterinary institutions between 2011 and 2020 were reviewed. Signalment, history, physical examination, diagnostics, days in hospital, anesthetic and procedure times, intraoperative/postoperative complications, conversion rates, duration of indwelling thoracic drain, and long-term outcomes were recorded. Results: Nine patients underwent a TL approach and 3 underwent TAL. In those that underwent TL, conversion to an intercostal thoracotomy was performed in 4 out of 9 dogs. Conversion was performed due to adhesions (n = 3) or poor visualization (1). Histopathologic examination was consistent with pneumonia due to an infectious process (n = 10), bronchioalveolar malformation with abnormal cilia (1), and left-sided cardiac insufficiency vs. pulmonary alveolar proteinosis (1). The mean duration of hospital stay was 4 days (range, 1-6 days). Complications occurred postoperatively in 7 dogs and included self-limiting hemorrhage (n = 3), self-resolving pneumothorax (2), incisional dehiscence (1), and severe dyspnea in a brachycephalic breed leading to euthanasia (1). For the 11 dogs that survived the perioperative period, there was no evidence of recurrence with a median follow up of 24 months (range, 5-120 months). Conclusion: Thoracoscopic (TL) and thoracoscopic-assisted lung lobectomy (TAL) is a reasonable surgical approach in select dogs with PC. Clinicial relevance: Conversion rates were higher than those historically reported for dogs undergoing thoracoscopic lung lobectomy for primary lung tumors.

Answer 132

Objective: To determine the accuracy of needle arthroscopy (NA) for the diagnosis of medial meniscal tears in dogs with cranial cruciate ligament rupture (CCLR). Study design: Prospective clinical trial. Animals: Twenty-six client-owned dogs. Methods: Dogs with CCLR and scheduled to undergo tibial plateau leveling osteotomy were recruited for the study. Needle arthroscopy was performed by an experienced surgeon; the same dog subsequently underwent standard arthroscopy (SA) by another experienced surgeon who was blinded to the NA findings. The SA arthroscopy findings were used as the gold standard. Arthroscopy time, visibility of the menisci, ability to probe the menisci, and the presence of meniscal tears were recorded for both arthroscopies. The degree of lameness before and after NA was subjectively quantified. Results: The sensitivity and specificity to diagnose medial meniscal tears with NA was 95% and 100%, respectively. Visibility of the menisci was lower (P < .01), probing of the lateral meniscus was harder (P = .0017), and procedure time was shorter (P = .073) with NA when compared to SA. The lameness scores did not differ before and after NA (P = .25). Conclusion: Needle arthroscopy could be performed rapidly with low morbidity, and had high accuracy for detecting medial meniscal tears in dogs with CCLR. Clinical significance: Needle arthroscopy is a promising minimally invasive technique for diagnosing medial meniscal tears in dogs with CCLR.

Answer 133

Objective: To describe the technique, complications, and outcome of the laparoscopic extra-abdominal transfascial suturing method for diaphragmatic rupture repair in a cat. Study design: Case report. Animals: A 10 year old, female domestic shorthair cat. Methods: An acute traumatic diaphragmatic rupture was diagnosed in a cat. Following initial stabilization, 3-port laparoscopic surgery was performed. After the laparoscopic reduction of herniating organs, a circumferential diaphragmatic tear was diagnosed, which was repaired using a multiple extra-abdominal transfascial suture technique. The total surgical time was 50 min with no intraoperative complications encountered. Results: The successful procedure was confirmed by normalization of chest radiography, clinical signs, and blood gas analysis in the perioperative and postoperative periods. Mild skin irritation occurred 3 weeks after surgery but was resolved following the removal of sutures. The cat recovered well without major complications; the final reexamination was performed 3 months postoperatively. Conclusion: The laparoscopic extra-abdominal transfascial suturing technique appears to be a feasible, and effective technique for feline diaphragmatic circumferential rupture repair. This technique may be an alternative option to intracorporeal suturing for diaphragmatic rupture treatment in the cat.

Answer 134

Objective: To describe arthroscopic-assisted hip toggle stabilization (AA-HTS) in cats, evaluate its feasibility and associated rate of iatrogenic injury, and assess deviations from planned surgical technique. Study design: Ex vivo study. Animals: Skeletally mature cat cadavers (n = 7). Methods: Preoperative pelvic computed tomography (CT) was performed for surgical planning and to identify the ideal femoral bone tunnel projection. Ultrasound-guided transection of ligament of head of femur was performed. Following exploratory arthroscopy, AA-HTS was performed using a commercially available aiming device. Surgical time, intraoperative complications, and feasibility of technique were recorded. Iatrogenic injury and technique deviations were assessed by postoperative CT and gross dissection. Results: Diagnostic arthroscopy and AA-HTS were successfully performed in all 14 joints. Median (range) surgical time was 46.5 (29-144) min, including 7 (3-12) min for diagnostic arthroscopy and 40 (26-134) min for AA-HTS. Intraoperative complications occurred in 5 hips, related to bone tunnel creation (4) and toggle dislodgment (1). Toggle passage through the femoral tunnel was the most challenging component of technique, recorded as mildly difficult in 6 joints. No damage to periarticular/intrapelvic structures was identified. Minor articular cartilage damage (<10% total cartilage area) was identified in 10 joints. Thirteen deviations (8 major, 5 minor) in surgical technique from preoperative planning were identified in 7 joints. Conclusion: In feline cadavers AA-HTS was feasible but was associated with a high rate of minor cartilage injury, intraoperative complications, and technique deviations. Clinical significance: Hip toggle stabilization using an arthroscopic-assisted approach may be an effective technique for management of coxofemoral luxation in cats.

Answer 135

Objective: To compare short- and long-term clinical variables between dogs undergoing a modified percutaneous cystolithotomy (PCCLm) and open cystotomy (OC) and evaluate for risk factors associated with complications and outcomes within the groups. Study design: Retrospective study. Animals: A total of 218 dogs. Methods: Records were reviewed for dogs that underwent PCCLm or OC between January 2010 and December 2019. Signalment; history and diagnostic findings; procedural, anesthetic, and hospitalized care data; complications; urolith recurrence; and follow-up were recorded. Logistic regression analysis was used to evaluate effects of clinical variables on outcomes within PCCLm and OC groups and to identify significant categorical variables between PCCLm and OC groups. Two sample t-tests were used to identify significant numerical variables between PCCLm and OC groups. Results: A total of 60.1% (131/218) of dogs underwent the PCCLm procedure and 39.9% (87/218) of dogs underwent the OC procedure. Anesthesia time (p < .001) was significantly longer in the OC group. No significant difference in incomplete urolith removal was noted between groups. Although surgical site infection and inflammation rates were not significantly different between OC and PCCLm groups, incisional infections were significantly associated with complications occurring during PCCLm (p = .027). Significantly reduced postoperative lower urinary tract signs (p = .022) were noted in the PCCLm group. Conclusion: The PCCLm may result in reduced lower urinary tract signs postoperatively compared to OC, but other clear advantages of the PCCLm were not identified in this study. Clinical significance: PCCLm procedures are an effective alternative to OC for urolith removal in dogs.

Answer 136

Objective: To develop and describe a minimally invasive technique for excisional biopsy of the axillary lymph nodes in dogs. Study design: Descriptive cadaver and clinical case series. Animals: Four canine cadavers and three clinical patients. Methods: A 3D computed tomographic reconstruction of the canine axilla was used to identify an optimal avenue of approach to the lymph nodes. This approach was refined using endoscopic techniques in four cadavers (six procedures) and potential surgical hazards, landmarks, and the surgical time required for excisional biopsy of the nodes was recorded. The procedure was then performed in three clinical cases. Results: Axillary lymph node removal was achieved using an endoscopic technique with surgical times of 58 and 35 minutes in two of three clinical cases. The third case required conversion to an open approach after endoscopic identification of the node. No major complications were encountered. Conclusion: Excisional biopsy of the axillary lymph nodes can be performed successfully using a minimally invasive technique in the dog. Further investigation in clinical cases is needed to determine the risks and complications of this procedure. Clinical significance: Minimally invasive excisional biopsy of the axillary lymph nodes in dogs can be performed and may have a role in assisting with staging and local disease control in oncologic cases.

Answer 137

Objective: To summarize the current peer-reviewed publications on minimally invasive surgery (MIS) for medial coronoid process disease (MCPD) in dogs. Study design: Invited review. Methods: Pubmed, CAB Abstracts and Scopus databases were utilized for literature review (1990-2023). Results: More than 60 papers have been published that involve MIS evaluation or treatment of MCPD. Six prospective trials incorporated quantitative gait analysis evaluating outcome following MCPD debridement, of which three included a control group. Whilst case numbers were limited, all studies employing a control group failed to demonstrate superiority of surgery over nonsurgical management. Of three studies employing gait analysis and no control group, all documented some improvement in function compared to pretreatment lameness. Multiple studies document progression of osteoarthritis in dogs following MCPD debridement although this may not be synonymous with worsened function. Subtotal coronoid osteotomy (SCO) is described as an alternative to MCP fragment removal, although the long-term biomechanical consequences are currently unclear and quantitative data on the efficacy of this treatment in isolation for MCPD is awaited. Conclusion: Arthroscopy of the canine elbow joint is a safe means by which to evaluate MCP pathology. Quantitative longitudinal analysis of outcome following minimally invasive surgery for MCPD is required. Correlation with clearly defined subclassification inclusion criteria such as age, incongruity and the precise arthroscopic findings in each case are required to more accurately differentiate any superiority of surgery over nonsurgical management for this disease.

Answer 138

Objective: Assess the accuracy and efficiency of reduction provided by application of plates precontoured to 3-dimensional (3D)-printed femoral bone models using a custom fracture reduction system (FRS) or intramedullary pin (IMP) to facilitate femoral minimally invasive plate osteosynthesis (MIPO) in dogs. Study design: Experimental cadaveric study. Sample population: Seven dog cadavers. Methods: Virtual 3D femoral models were created using computed tomographic images. Simulated, virtual mid-diaphyseal femoral fractures were created and reduced. Reduced femoral models were 3D-printed and a plate was contoured. Custom drill guides for plate screw placement were designed and 3D-printed for the FRS. Mid-diaphyseal simulated comminuted fractures were created in cadavers, and fractures were aligned using FRS or IMP and stabilized with the precontoured plates. Number of fluoroscopic images acquired per procedure and surgical duration were recorded. Computed tomographic scans were repeated to assess femoral length and alignment. Results: Compared to the preoperative virtual plan, median change in femoral length and frontal, sagittal, and axial alignment was less than 3 mm, 2°, 3°, and 3° postoperatively, respectively, in both reduction groups. There was no difference in length or alignment between reduction groups (P > .05). During FRS, fewer fluoroscopic images were taken (P = .001), however, surgical duration was longer than IMP procedures (P = .011). Conclusion: Femoral alignment was accurate when using plates precontoured to 3D printed models, regardless of reduction method. Clinical significance: Accurate plate contouring using anatomically accurate models may improve fracture reduction accuracy during MIPO applications. Custom surgical guides may reduce fluoroscopy use associated with MIPO.

Answer 139

Objective: To evaluate long-term clinical outcomes of dogs surgically treated for proximal humeral osteochondrosis (OC). Study design: Cross-sectional study. Sample population: Twenty dogs (n = 26 shoulders). Methods: Dogs treated with surgical debridement of proximal humeral OC lesions >12 months prior were enrolled. Orthopedic examination (including limb circumference and shoulder goniometry), kinetic gait analysis, shoulder radiographs, shoulder computed tomography (CT), and shoulder arthroscopy were performed. All owners completed a dog mobility questionnaire. Results: Brachial circumference (P = .003) and maximum shoulder extension (P = .013) were decreased and maximum shoulder flexion (P = .008) was increased (ie less flexion) in the OC limb versus the contralateral limb in unilaterally affected dogs. There were no differences in peak vertical force and vertical impulse between affected and unaffected limbs. Dogs demonstrated a 4.4% decrease in load distributed to the operated limb. Osteoarthritis was present in all shoulders treated for OC lesions. The degree of osteoarthritis in OC-affected shoulders was increased compared to the contralateral limb as evaluated on CT (P = .005) and radiography (P = .0001) in unilaterally affected cases. Moderate-to-severe synovitis was seen in all OC-affected joints. Arthroscopically, all lesions were noted to have patchy, incomplete cartilaginous infilling. Median of aggregate Liverpool Osteoarthritis in Dogs (LOAD) scores was 6. Conclusion: All dogs exhibited ipsilateral muscle atrophy and progressive osteoarthritis, with most dogs exhibiting subtle lameness on the subjective gait examination. Despite this, owner-perceived mobility was satisfactory. Clinical significance: Progression of joint disease over time should be expected; however, the abnormalities detected on examination appear to be of questionable clinical relevance.

Answer 140

Objective: To evaluate factors contributing to owner decision-making, satisfaction, and perception of quality of life (QOL) with treatment of dogs with nontraumatic hemoabdomen (NTH). Animals: 132 client-owned dogs. Procedures: An electronic survey was administered to owners of 436 dogs that presented emergently with NTH to a single institution between January 2015 and May 2022. Following survey response, retrospective data collection was performed. Results: Owners reported QOL as the most important factor influencing their decision-making (92%), followed by risk of cancer (57%) or time remaining with their pet (56%). QOL scores were significantly higher with surgery versus those with palliative care (P = .007). Median survival time (MST) was 213 days with surgery and 39 days with palliative care (P = .049). Survival benefit of surgery was lost when considering only dogs with malignant histopathology (MST, 81 days; P = .305). Owners were more likely to be satisfied when they chose surgery over either euthanasia or palliative care (P = .039). Thirty-four owners (26%) second-guessed or were unsure of their decision. Clinical relevance: Surgery resulted in the longest MST with greater perceived QOL and owner satisfaction compared with both palliative care and euthanasia and should therefore be considered highly. The importance of malignancy and survival time on owners' decisions, along with the negative impact of metastasis on survival, underscores the importance of timely preoperative staging. The rate of second-guessing highlights the need for standardization of NTH discussions including treatment options and potential outcomes in order to effectively and efficiently guide treatment of patients with this common presentation.

Answer 141

Objective: The aim of this study was to assess the kinetic and radiographic outcome of unilateral double pelvic osteotomy (DPO) using a temporospatial pressure walkway, preoperative and postoperative radiographs. Study design: Retrospective case series of six dogs that underwent unilateral DPO for canine hip dysplasia. The untreated limb was unfit for DPO due to radiographic evidence of osteoarthritis and was therefore managed non-surgically. Preoperative and postoperative radiographs and kinetic data were compared between untreated and DPO-treated hips using a Wilcoxon signed-rank test. Results: There was no significant difference in British Veterinary Association Hip Dysplasia Scheme (BVA-HD) scores between untreated and DPO-treated hips preoperatively (p-value = 0.09) and postoperatively (p-value = 0.06). The median postoperative GAIT4 Dog Lameness Score was lower in untreated hips than DPO-treated hips but was not statistically different (p-value = 0.18). Conclusions: All dogs in this case series achieved a total pressure index and GAIT4 Dog Lameness Score on the DPO-treated hip comparable to normal limbs. All untreated hips in this series had increased BVA-HD scores at follow-up, whereas all DPO-treated hips had reduced BVA-HD scores. This difference was not significant and warrants further studies. We conclude total pressure index may be preserved in hips treated with unilateral DPO, while the contralateral hip is managed non-surgically.

Answer 142

Objectives: Two-dimensional measurements of acetabular geometry are widely used for the assessment of acetabular component orientation following total hip replacement (THR). With the increasing availability of computed tomography scans, there is an opportunity to develop three-dimensional (3D) planning to improve surgical accuracy. The aim of this study was to validate a 3D workflow for measuring angles of lateral opening (ALO) and version, and to establish reference values for dogs. Methods: Pelvic computed tomography scans were obtained from 27 skeletally mature dogs with no radiographic evidence of hip joint pathology. Patient-specific 3D models were built, and ALO and version angles were measured for both acetabula. The validity of the technique was determined by calculating intra-observer coefficient of variation (CV, %). Reference ranges were calculated and data from left and right hemipelves were compared using a paired t-test and symmetry index. Results: Measurements of acetabular geometry were highly repeatable (intra-observer CV 3.5-5.2%, inter-observer CV 3.3-5.2%). Mean (± standard deviation) values for ALO and version angle were 42.9 degrees (± 4.0 degrees) and 27.2 degrees (± 5.3 degrees) respectively. Left-right measurements from the same dog were symmetrical (symmetry index 6.8 to 11.1%) and not significantly different. Conclusions: Mean values of acetabular alignment were broadly similar to clinical THR guidelines (ALO of 45 degrees, version angle of 15-25 degrees), but the wide variation in angle measurements highlights the potential need for patient-specific planning to reduce the risk of complications such as luxation.

Answer 143

Objective: The main aim of this study was to determine the effective magnitude of proximal tibial segment medialization achievable during tibial plateau levelling and medialization osteotomy (TPLO-M) with Fixin 1.9-2.5 mm pre-contoured T plates with three different offsets. Methods: In this in vitro study, 36 tibia bone models reconstructed using stereolithography from hindlimb CT scans of a 5 kg dog and a 10 kg dog without orthopaedic disease were used. TPLO-M was performed using plates with three different offsets (2, 4 and 6 mm). Post-osteotomy radiographic and bone models measurements were performed. Results: Regardless of patient weight, the +4 mm offset plates provided a translation of 2.93mm (± 0.51) while the +6 mm offset plates provided a translation of 5.03mm (± 0.47). In the 5kg dog bone model group limited bone contact at the osteotomy site was documented when using the +6mm offset plate. Conclusion: The +4mm and +6mm offset Fixin plates may be considered for TPLO-M in dogs weighing between 5 and 10 kg. The +6mm offset plate should be used cautiously in dogs weighing less than 10 kg since this plate may result in insufficient postoperative bone apposition at the osteotomy site.

Answer 144

Objective: To compare angled dynamic compression holes in a tibial plateau levelling osteotomy (TPLO) plate to a commercially available TPLO plate in an ovine cadaveric model. Study design: Ovine tibias (40 bones) were mounted on a custom-made securement device and radiopaque markers were placed to aid radiographic measurements. A standard TPLO procedure was performed on each tibia with either a custom-made six-hole 3.5 mm angled compression hole plate (APlate) or a six-hole 3.5 mm standard commercial plate (SPlate). Radiographs were obtained before and after tightening of the cortical screws and evaluated by an observer blinded to the plate. Measurements of cranio-caudal displacement (CDisplacement), proximo-distal displacement (PDisplacement) in relation to the long axis of the tibia, and change in tibial plateau angle (TPA) were determined. Results: CDisplacement was significantly greater in APlate (median 0.85 mm, Q1-Q3: 0.575-1.325 mm) compared to SPlate (median 0.00 mm, Q1-Q3: -0.35-0.50 mm, p < 0.0001). There were no significant differences in the PDisplacement (median 0.55 mm, Q1-Q3: 0.075-1.00 mm, p = 0.5066) or TPA change (median -0.50°, Q1-Q3: -1.225-0.25°, p = 0.1846) between the two plate types. Conclusion: APlate increases cranially directed displacement of the osteotomy in a TPLO procedure without causing TPA change. The reduced interfragmentary distance across the whole osteotomy could improve osteotomy healing compared to standard commercial TPLO plates.

Answer 145

Objective: The aim of this study was to determine the factors related to functional patella alta, with which the proximodistal patellar position exceeds the reference range of healthy small dogs proximally when the stifle is at full extension. Study design: Mediolateral-view radiographs of dogs weighing less than 15 kg were obtained and classified into the medial patellar luxation (MPL) and control groups. The reference range of the proximodistal patellar position was determined from the control group. In both groups, a patellar position exceeding this reference range proximally was considered functional patella alta. Multiple logistic regression analysis was performed to examine the factors related to functional patella alta. A receiver operating characteristic (ROC) curve was made for each factor. Results: Overall, radiographs of 127 stifles of 75 dogs were obtained. Eleven stifles in the MPL group and one stifle in the control group were determined to be functional patella alta. The factors associated with functional patella alta included a greater full extension angle of the stifle joint, longer patellar ligament, and shorter femoral trochlear length. The full extension angle of the stifle joint had the biggest area under the ROC curve. Conclusion: Mediolateral radiographs of the stifle joint in full extension are clinically important in dogs with MPL because some dogs might have a proximally positioned patella that is recognizable only when the stifles are extended.

Answer 146

Objectives: The main aim of this study was to report the surgical technique, the complications and the clinical outcomes of the mini-Tight Rope system (mini-TR) for a modified hip toggle stabilization of coxofemoral luxation in cats. Study design: A multicentre retrospective study. Animals: Thirty-two client-owned cats. Methods: Medical records (2009-2017) of cats, which underwent stabilization of a coxofemoral luxation with the mini-TR and had at least a 3-month follow-up, were reviewed. The femoral tunnel diameter, the use of one or two FiberWire loops, perioperative complications and clinical outcomes were recorded. Follow-up information was obtained through clinical and radiographic examinations and an owner questionnaire. Results: Thirty-two cats met the inclusion criteria. Concurrent injuries were present in 16 cats. A single or double loop mini-TR was used in 21 and 12 cats respectively. One double loop (1/12 cats) and four single loop (4/16 cats) sutures failed. Moderate-to-severe coxofemoral osteoarthritis developed in 14/27 cats. Owner questionnaires revealed excellent clinical outcomes. Clinical significance: Mini-TR with a double-stranded implant is recommended to decrease the risk of suture failure. Osteoarthritis is common after open reduction of hip luxations.

Answer 147

Objectives: The purpose of this cadaveric study was to determine whether patient-specific guides (PSGs) improve the accuracy of tibial and femoral cut alignment in canine total knee replacement (TKR), as compared with generic cutting guides. Study design: Original research. Animals: Sixteen pelvic limbs from skeletally mature medium- to large-breed canine cadavers. Methods: Specimens were randomly allocated to one of two groups (PSG or Generic; N = 8/group). In the Generic group, femoral and tibial ostectomies were made using the standard canine TKR femoral cutting blocks and tibial alignment guide. In the PSG group, the cuts were made using a series of custom 3D-printed cutting guides. "Planned" and "actual" tibial and femoral cut alignments were compared in the frontal and sagittal planes, and errors were calculated by subtracting actual from planned values. Results: Use of 3D-printed PSGs improved tibial cut alignment in the frontal plane but not the sagittal plane. PSGs also improved the alignment of the cranial and distal femoral ostectomies but did not impact varus-valgus alignment. Conclusions: These findings support the use of PSGs for TKR in dogs. Clinical trials are now needed to determine whether the benefits of PSGs translate into measurable improvements in joint function and implant longevity. Clinical significance: PSGs have the potential to improve femoral and tibial component alignment in canine TKR.

Answer 148

Objectives: To investigate stifle kinematics and kinetics following TPLO and TPLO combined with an extra-articular lateral augmentation (TPLO-IB) during the tibial compression test (TCT) and the tibial pivot compression test (TPT), applied with an external (eTPT) and an internal moment (iTPT). Study design: Experimental ex vivo study. Sample population: Ten cadaveric hindlimbs of dogs weighing 23-40 kg. Methods: 3D-kinematic and kinetic data were collected while performing TCT, eTPT, and iTPT and compared under the conditions (1) normal, (2) CCL deficient, (3) TPLO, and (4) TPLO-IB. Two-way repeated-measures ANOVA was used to examine the effect of test and treatment on kinetic and kinematic data. Results: Mean ± SD preoperative TPA was 24.7° ± 1.7°, postoperative TPA was 5.9° ± 0.7°. During TCT, there was no difference in cranial tibial translation between the intact stifle and after TPLO (p = .17). In contrast, cranial tibial translation was six times larger in TPLO compared to intact when performing eTPT and iTPT (p < .001). Cranial tibial translation with TCT, eTPT and iTPT was not different between intact stifle and TPLO-IB. Intraclass correlation coefficient for eTPT and iTPT after TPLO and TPLO-IB was excellent being 0.93 (0.70-0.99) and 0.91 (0.73-0.99), respectively. Conclusion: Whereas TCT is negative after TPLO, instability persists when a rotational moment is combined using eTPT and iTPT. TPLO-IB neutralizes craniocaudal and rotational instability when performing TCT, eTPT, and iTPT.

Answer 149

Objective: To report a modification of the tibial tuberosity transposition (m-TTT) technique used to treat medial patellar luxation (MPL) in dogs, and report its complications. Study design: Retrospective case series. Sample population: Dogs (n = 235) undergoing MPL correction, using m-TTT (n = 300 stifles). Methods: Medical records and client surveys were reviewed to determine complications associated with this technique and they were compared with previously reported complications using similar techniques. Results: Short-term minor complications included low-grade reluxation (11 stifles, 3.6%), incisional seroma (nine stifles, 3%), pin-associated swelling (seven stifles, 2.3%), patellar desmitis (six stifles, 2%), superficial incisional infection (four stifles, 1.3%), pin migration (three stifles, 1%), tibial tuberosity (TT) fracture (two stifles, 0.6%), tibial tuberosity displacement and patella alta (one stifle, 0.3%), pin-associated discomfort (one stifle, 0.3%), trochlear block fracture (one stifle, 0.3%). Short-term major complications included pin migration (three stifles, 1%), incisional infection (two stifles, 0.6%), tibial tuberosity fracture (two stifles, 0.6%), and high grade reluxation (two stifles, 0.6%). Long-term follow-up examination data were available for 109/300 (36.3%) stifles. One minor complication and four major complications were documented. All long-term complications were due to pin migration. The overall major complication rate was 4.3% (13/300 stifles), with a minor complication rate of 15% (46/300 stifles). The owner survey indicated a 100% satisfaction rate. Conclusion: The m-TTT technique yielded acceptable complication rates, with high owner satisfaction. Clinical significance: The m-TTT should be considered as an alternative technique for treating dogs with MPL requiring a tibial tuberosity transposition.

Answer 150

Objective: To determine the influence of extreme brachycephalic conformation on presenting signs, imaging findings, intraoperative and perioperative complications following total ear canal ablation and lateral bulla osteotomy (TECA-LBO). Study design: Cross-sectional retrospective study. Animals: A total of 306 (n = 242 dogs) TECA-LBOs (extreme brachycephalic breeds [EBB] = 81, other breeds [OB] = 225). Methods: Medical records of patients undergoing TECA-LBO at a single referral institution (2010-2022) were evaluated. Results: Extreme brachycephalic breeds most commonly presented acutely, at a younger age with oto-neurological signs (46/81, 56.8%). Chronic otitis externa without neurological signs (171/225, 76.0%) was most common in OBs. Extreme brachycephalic breeds preoperatively presented more frequently with facial nerve paresis (p = .001), vestibular syndrome (p = .001), and Horner's syndrome (p = .002) compared to OBs. On diagnostic imaging, bilateral changes (p = .038), aural masses (p = .045), para-aural abscesses (p = .011), otitis interna (p = .001), and brainstem changes (p = .001) were more common in EBBs. The apparent difference in intraoperative complication rate between EBBs (9/81, 11.1%) and OBs (12/225, 5.3%) did not reach statistical significance (p = .078). Perioperative complications occurred in 85/306 (27.8%) of TECA-LBOs with no difference in perioperative complication rate between EBBs (19/81, 23.5%) and OBs (66/225, 29.3%) (p = .586). Conclusion: Extreme brachycephalic breeds are more likely to present for TECA-LBO acutely, with neurological signs and more advanced diagnostic imaging abnormalities. Intra- and perioperative complication rates did not differ between EBBs and OBs. Clinical significance: Despite being subjectively more technically challenging, TECA-LBO did not result in more surgical complications in EBBs. Reported data are useful for effectively informing clients of the specific risks of TECA-LBO surgery.

Answer 151

Objective: To compare leakage pressures of vesicourethral anastomosis (VUA) performed with conventional and unidirectional barbed sutures in canine cadaveric tissue. Study design: Experimental, ex-vivo, randomized study. Animals: A total of 24 male canine bladders with the urethra. Methods: Specimens after prostatectomy were randomly divided into a unidirectional barbed suture (UBS) or a conventional suture (C) group. For the UBS group, the VUA was performed with 4-0 unidirectional barbed sutures. For the C group, the VUA was performed with 4-0 monofilament absorbable suture. The VUA was completed with two simple continuous sutures. Surgical time, leakage pressure, site of leakage, and the number of suture bites were recorded. Results: The median suturing time was 12.70 minutes (range: 7.50-16.10 min) for the UBS group and 17.30 minutes (range: 14.00-21.30 min) for the C group (p < .0002). The median leakage pressure was 8.60 mmHg (range: 5.00-17.20 mmHg) for the UBS group and 11.70 mmHg (range: 6.00-18.50 mmHg) for the C group (p = .236). The median number of suture bites was 14 (range:11-27) for the UBS group and 19 (range:17-28) for the C group (p = .012). Conclusion: Unidirectional barbed suture does not statistically affect the acute leakage pressure of VUA in normal cadaveric specimen. It resulted in a shorter surgical time and fewer suture bite placements. Clinical significance: A urinary catheter will still be required when a unidirectional barbed suture is used to complete a VUA in dogs to prevent extravasation of urine in the postoperative period.

Answer 152

Objective: To determine if closed glove exchange (CGE) increases hand contamination. Study design: Prospective experimental study. Sample population: Surgical teams participating in 65 individual surgical procedures were included, resulting in 200 individual enrollments. Methods: At the completion of surgery, gloves were removed and hands were swabbed. The inside of the gown cuff was swabbed. Each participant regloved, using a closed gloving technique. The new gloves were removed, and hands were swabbed for culture a second time. Swabs underwent standard bacterial culture. Results: Before glove exchange, or baseline, contamination was found on 17/200 dominant hands and 13/200 nondominant hands. After performing CGE, contamination was found on 14/200 and 15/200 dominant and nondominant hands, respectively. No difference was detected between the number of CFUs cultured from a surgeon's hands before CGE and the number of CFUs cultured from a surgeon's hands post-CGE (one sided sign test, p = .61). Twelve (12) different bacterial species were identified, the most common were Staphylococcus spp. (97/154; 63%). Conclusion: Closed glove exchange did not increase bacterial hand contamination over baseline levels. Clinical significance: We found no evidence to support discontinuing CGE.

Answer 153

Objective: To compare the analgesic effect of surgical wound infiltration with liposomal bupivacaine (LB) to saline placebo in dogs after tibial plateau leveling osteotomy (TPLO). Study design: Blinded, randomized, placebo-controlled clinical prospective study. Animals: Fifteen client-owned dogs receiving LB and 17 dogs receiving an equivalent volume of saline placebo, all with confirmed unilateral cranial cruciate ligament insufficiency. Methods: Preoperatively and up to 48 h after surgery, Glasgow Composite Measure Short Form (CMPS-SF) pain scores were assigned and using a weight distribution platform, static bodyweight distribution (%BWdist ) to the operated limb was measured. Postoperatively, dogs also received carprofen 2.2 mg/kg subcutaneously every 12 h. Rescue analgesia was provided. Treatment success was defined as not requiring rescue analgesia over the 48-h postoperative period. Results: There was no difference between treatment success, postoperative opioid consumption, CMPS-SF pain scores, or %BWdist in dogs that received surgical wound infiltration with LB compared with those receiving saline placebo, following TPLO. There was no linear correlation between CMPS-SF pain scores and %BWdist . Conclusion: For the population of dogs that underwent TPLO and received postoperative carprofen at our institution, LB did not provide an analgesic effect discernable by success/failure analysis, CMPS-SF pain scores, or %BWdist measurement using a weight distribution platform, compared with saline placebo. Clinical significance: LB may not provide detectable analgesia during the first 48 h for dogs recovering from TPLO and receiving only postoperative carprofen.

Answer 154

Objectives: To investigate the accuracy and intra- and interobserver reliability of the cranial drawer test (CD), tibial compression test (TCT), and the new tibial pivot compression test (TPCT) in an experimental setting resembling acute cranial cruciate ligament rupture (CCLR) and to elucidate the ability to subjectively estimate cranial tibial translation (CTT) during testing. Study design: Experimental ex vivo study. Sample population: Ten cadaveric hindlimbs of large dogs. Methods: Kinetic and 3D-kinematic data was collected while three observers performed the tests on each specimen with intact (INTACT) and transected cranial cruciate ligament (CCLD) and compared using three-way repeated-measures ANOVA. Subjectively estimated CTT (SCTT), obtained during a separate round of testing, was compared to kinematic data by Pearson correlation. Results: CTT was significantly higher for CCLD than for INTACT for all tests, resulting in 100% sensitivity and specificity. TPCT induced the highest CTT and internal rotation. Intra- and interobserver agreement of translation was excellent. For rotation and kinetics, agreement was more variable. SCTT strongly correlated with the objectively measured values. Conclusion: The CD, TCT and the new TPCT were all accurate and reliable. The high translations and rotations during TPCT are promising, encouraging further development of this test. SCTT was reliable in our experimental setting. Clinical significance: Veterinary manual laxity tests are accurate and reliable in acute CCLR. The TPCT might have potential for the assessment of subtle and rotational canine stifle instabilities. The high reliability of SCTT implies that grading schemes for stifle laxity, similar to human medicine, could be developed.

Answer 155

Objective: To determine whether one larger or two smaller diameter pins used for tibial tuberosity avulsion fracture (TTAF) stabilization provides greater axial tensile strength and stiffness when subjected to monotonic mechanical load to failure in normal skeletally mature canine cadavers. Study design: Paired ex vivo biomechanical study. Sample population: Eleven pairs of adult cadaveric dog tibias. Methods: Twenty-two tibias from 11 dogs were collected to model a TTAF. Each limb of a pair was randomly assigned a one or two-pin fixation. Tibias were subjected to monotonic, axial load to failure. Fixation stiffness, strength, and pin insertion angles were analyzed with parametric testing. Significance was set at p < .05. Results: The mean strength of the single-pin fixation was 426.2 ± 50.5 N compared to two-pin fixation at 639.2 ± 173.5 N (p = .003). The mean stiffness of the single-pin fixation was 57.3 ± 18.7 N/mm and the two-pin fixation was 71.7 ± 20.5 N/mm (p = .029). The normalized ratio between one and two-pin fixation had a mean stiffness of 68% ± 25.8% and strength of 82.8% ± 24.6%. Conclusions: In an ex vivo cadaveric TTAF model, vertically aligned two-pin fixation offers greater strength and stiffness when compared to a single-pin fixation. Clinical significance: When repairing TTAF, surgeons should aim to apply two vertically aligned pins rather than a single pin for greater strength and stiffness.

Answer 156

Objective: To describe the application and early outcome of a custom-made unipolar partial tarsal replacement in a dog with an extensive medial talar ridge OCD. Animal: A 7-month-old, 25 kg male Rhodesian Ridgeback with progressive left hindlimb lameness (grade III-IV/IV) and diagnosis of talar OCD. Methods: The dog presented with progressive lameness attributed to extensive medial talar ridge OCD. Due to the severity of the lesion, a resurfacing procedure was chosen. Based on CT data, a bi-layered resurfacing implant consisting of a titanium socket and a polycarbonate urethane bearing surface was constructed. For intraoperative guidance, a set of matching drill guides were 3D-printed, along with some models of the affected talus, to allow for dry-lab training. Surgical implantation using a medial malleolar osteotomy to approach the lesion was without complications. Orthopedic follow-up examinations were conducted at 10 days, 4 weeks, 6 weeks, 6 months and 12 months. Radiographic examinations were included at the 6-week, 6-month, and 12-month follow-ups. Results: Function improved considerably during the follow-up period with a lameness grade of 0-I/IV at the 12-month follow-up. ROM differed by 15° in flexion compared to the contralateral side, while there was no difference in extension. Moderate periarticular fibrosis was present at 12 months. Implant positioning was unchanged at follow-up-radiographic examination and there was only mild progression of osteoarthritis (OA). Conclusion: Patient specific instrumentation - guided tarsal OCD resurfacing with a synthetic patient-specific implant may be an effective treatment option.

Answer 157

Objective: To compare pin placement accuracy, intraoperative technique deviations, and duration of pin placement for pins placed by free-hand probing (FHP) or 3D-printed drill guide (3DPG) technique. Sample population: Four greyhound cadavers. Methods: Computed tomography (CT) examinations from T6-sacrum were obtained for determination of optimal pin placement and 3DPG creation. Two 3.2/2.4-mm positive profile pins were inserted per vertebra, one left and one right from T7-L7 (FHP [n = 56]; 3DPG [n = 56]) by one surgeon and removed for repeat CT. Duration of pin placement and intraoperative deviations (unanticipated deviations from planned technique) were recorded. Pin tracts were graded by two blinded observers using modified Zdichavsky classification. Descriptive statistics were used. Results: A total of 54/56 pins placed with 3DPGs were assigned grade I (optimal placement) compared with 49/56 pins using the FHP technique. A total of 2/56 pins placed with 3DPGs and 3/56 pins using the FHP technique were assigned grade IIa (partial medial violation). A total of 4/56 pins placed using the FHP technique were assigned grade IIIa (partial lateral violation). No pins were assigned grade IIb (full medial violation). Intraoperative technique deviations occurred with 6/56 pins placed using the FHP technique and no pins with 3DPGs. Overall, pins were placed faster (mean ± SD 2.6 [1.3] vs. 4.5 [1.8] min) with 3DPGs. Conclusions: Both techniques were accurate for placement of spinal fixation pins. The 3DPG technique may decrease intraoperative deviations and duration of pin placement. Clinical relevance: Both techniques allow accurate pin placement in the canine thoracolumbar spine. The FHP technique requires specific training and has learning curve, whereas 3DPG technique requires specific software and 3D printers.

Answer 158

Objective: To determine the effect of flushing of the common bile duct (CBD) on hepatobiliary markers and short-term outcome in dogs undergoing cholecystectomy for the management of gallbladder mucocele (GBM). Study design: Randomized, controlled, prospective study. Animals: Thirty-two client-owned dogs. Methods: Dogs were allocated randomly to either a "flush" group or a "non-flush group." Flushing was performed in a normograde fashion, followed by a routine cholecystectomy. Data collected included presenting clinical signs, preoperative and 3-day postoperative hepatobiliary markers (alkaline phosphatase, ALP; alanine aminotransferase, ALT; gamma glumatyl-transferase, GGT; bilirubin; cholesterol; triglycerides), duration of hospitalization, and complications. These data were compared between groups. Results: Sixteen dogs were enrolled in each group. One dog (in the flush group) was excluded following diagnosis of hepatic lymphoma. Border terriers were overrepresented (20/31). Overall, there were marked reductions from preoperative to 3 days postoperative in serum bilirubin (p = .004), ALP (p = .020), ALT (p < .001), GGT (p = .025), and cholesterol (p < .001) values. There was no difference in any marker between groups. Survival to discharge was 90.3% (28/31 dogs). Conclusion: Cholestatic markers decreased significantly 3 days postcholecystectomy. No short-term clinical or clinico-pathological benefits were identified when flushing the CBD in dogs undergoing cholecystectomy for GBM. Clinical significance: The findings of the study do not support routine flushing of the CBD during cholecystectomy for GBM in dogs.

ABSTRACT - 202307-202402 Flashcards

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