Ch 31 Cervical vertebral column Flashcards

Question

What is this device? What are its advantages?

Answer 1

Kishigami tension band for dorsal stabilisation of AA sublux Reduced risk of damaging the spinal cord as it does not need to be passed under the dorsal arch

Answer 2

Transarticular screws or pins - 47% Pins and PMMA - 94% (long-term complications 34%) Screws and PMMA (placed 30-40 degrees) Ventral plating (mini H-plate 2.0mm, 5-hole butterfly plate 1.5mm)

Answer 3

**40+/-1** degree in medial to lateral direction **20+/-1** degree in VD direction from ventral aspect of vertebral foramen of the axis Mean corridor length 7mm, width 3-5mm AIming in a craniolateral direction

Answer 4

Dorsal 71% Ventral 53% Implant failure of the transarticular pins most common complications. Implant failure 48% dorsal vs 44% ventral, may or may not require re-op Fracture of the Atlas or Axis The dorsal arch of the atlas can fracture following a dorsal stabilization techniqu Episodic pain has been reported in dogs for several months to life postoperatively Improper pin placement with inadequate bone purchase is the main cause of implant migration. Implant failure can be an incidental finding at recheck post-op nsaid, monitor, restrict 4-8wks | another surgery may not be necessary, > strong fibrous or osseous union.

Answer 5

**Age**of onset: Dogs under 24m had greater odds of successful outcome **Duration**and severity of clinical signs: Under 10m associated with greater odds of successful outcome

Answer 6

conservative: good long-term outcome has been documented in 10 of 26 (38%) cases perioperative mortality rate: 4% and 30% of dogs

Answer 7

4 techniques (dorsal wire, modified dorsal clamp kishigami, ventral transarticular pin, and augmented ventral transarticular pin fixation). experimental (13 skull) The AAJs with dorsal wire, ventral transarticular pin, and augmented ventral transarticular pin fixations had similar biomechanical properties, but not clamp. load cycling and clinical studies are needed

Answer 8

To report outcome and complications following atlanto-axial stabilisation by polymethylmethacrylate applied to screws placed using 3D-printed patient-specific drill guides. Materials and Methods: Case series Of 61 bicortical screws placed, 57 (93%) were fully contained rate of vertebral canal screw penetration of 7% in this study compares favourably to previously reported values of 21% and 9% using similar patient-specific guides **stainless steel screws resulting in greater CT artefact then would have occurred with titanium screws**

Answer 9

ventral compression index: ratio between ventral and dorsal atlantodental interval - VCI ≥0.16 in extension (100% sens, 94.5% spec) ≥0.2 in flexion (100%, 96.7%)

Answer 10

cadavers The CT data revealed that TSF achieved significantly better apposition than cemented constructs 4.4% were graded as dangerous and 86.8% as optimal.

Answer 11

Study design: Retrospective multicenter study. Sample population: Client-owned dogs (n = 123) and 28 cadavers. ventral compression index (VCI f ≥0.16 in extended and ≥0.2 in flexed head positions were diagnostic for AAI (sensitivity of 100% and 100%, specificity of 94.54% and 96.67%, respectively).

Answer 12

These dorsal compressive lesions, identified with MRI, are a significant predictor of craniocervical junction abnormalities, such as atlantooccipital and AA instability, atlantooccipital overlap,

Answer 13

Brachiocephalic Suprascapular Subscapular Axillary Musculocutaneous Radial Median Ulnar Dorsal thoracic Lateral thoracic Long thoracic Pectoral Muscular branches

Answer 14

Class 1: Neurapraxia - interruption of the function and conduction of a nerve without structural changes. Reversible, up to 6 weeks to improve Class 2: Axonotmesis - crush or percussion injuries causing Wallerian degeneration. Internal architecture of the nerve, including the endoneurium and Schwann sheath is well preserved. Recovery expected but can take several weeks Class 3: Neurotmesis - Disruption of axons and endoneurium but fascicular orientation is maintained by intact perineurium Class 4: Neurotmesis - Disrupted perineurium Class 5: Neurotmesis - Entire nerve severed neurotmesis: Full recovery usually not seen and accompanied by scar.

Answer 15

myelin sheath for each myelinated axon is formed by Schwann cell plasma membranes wrapping around the axon like an “onion peel.” The Schwann cells are separated by junctions called nodes of Ranvier, which assist in the rapid conduction of action potentials along the axon. Endoneurium surrounds each axon Groups of axons are surrounded by perineurium tissue around the entire nerve, called the epineurium

Answer 16

Injury of the **cranial portion (C5-C7)** - Effects musculocutaneous, axillary, subscapular and suprascapular nerves. Loss of shoulder movement and elbow flexion, shoulder atrophy Injury to the **caudal potion (C8-T2)**- Radial, median and ulnar nerves. Cannot extened elbow and thererfore cannot weight bear. Radial nerve involved in 92% of dogs. Can sometimes see Horners syndrome and loss of cutaneous trunci **Complete injury (C6-T2)** - Drags leg knuckles, shoulder more ventral, hypotonic and atrophy If the injury is severe > damage the spinal cord - **ipsilateral pelvic limb** general proprioceptive ataxia - UMN paresis or plegia.

Answer 17

Early decreased radial nerve conduction velocity indicates a poor prognosis Electromyography allows detection of abnormal spontaneous electrical activity indicative of denervated muscles 1 week to 10 days after injury

Answer 18

Neurotization (nerve transfer) - Can be neuroneural or neuromuscular using 9-0 monofilament nylon Reimplantation via hemilaminectomy, durotomy, incision into pia mater and spinal cord Successful neurotization in cats using right lateral thoracic and thoracodorsal nerve to reinnervate the left transected musculocutaneous nerve adult dog, this **axonal regrowth** can reach at least 10 to 15 cm within a 4-month period

Answer 19

grave if radial nerve avulsion occurs Carpal arthrodesis or tendon transposition > triceps innervation is required to be able to bear weight through the elbow given at least 4 to 6 weeks before a grave prognosis Limb amputation should be discussed if self-mutilation becomes apparent and is not responsive

Answer 20

14-25% most type I extrusion smll.chondrodys breeds or Labs, doberman, dalmation

Answer 21

80% C2-C4 44-59% C2-C3 Caudal disc spaces are more common in Yorkies and Chihuahuas as well as large breeds

Answer 22

every intervertebral space (except between C1 and C2), uniting the bodies of adjacent vertebrae to form amphiarthrodial joints the widest cervical intervertebral spaces are C4-C5 and C5-C6; the narrowest is C2-C3. AF > provide a means for transmission of stresses and strains required by all lateral and upward movements. one and a half to three times thicker ventrally than dorsally hyaline cartilaginous end plates cover the epiphyses of the vertebral bodies > attached to annular lamellae, a continuation of the Sharpey fibers

Answer 23

Dorsal longitudinal (dorsal to AF) thickest in the cervical vertebral column, offering greater resistance to dorsal herniation of nucleus pulposus material ventral longitudinal epidural space ventral yellow (ligamentum flava) interspinous and supraspinous

Answer 24

FCE AA CSM MUO Noeplasia Fracture/luxation Disco cyst syringohydromyelia

Answer 25

45% acute, hyperaethesia 90%, 60% minimal signs (dt larger canal) nerve root signature 34% LMN cor C1-5 in msall dogs respiratory comromise > paresis/paralysis of resp. muscles causes hypoventilation

Answer 26

1. CSF 2. rads: rule out disco/#/malformation. Narrow IVd/mineralisation (25% accuracy) 3. myelogram CT: heterogenous, hyperattenuating extradural mass with loss of epidural fat. possible compression inversely proprtional to ppst-op neuro status 4. MRI: nonivasive, high res image with increase localisation accuracy compared to CT. degree of compresion not prognostic. Hypointense on T2W ID hydrated IVD (hyperintense, seagull)

Answer 27

enables resolution of the inflammation and stabilization of the ruptured intervertebral disc by fibrosis, preventing further herniation 4-6 weeks rest meds | 36% recurrence

Answer 28

Intradiscal injection of chondroitinase ABC to treat disc herniation. 92% of dogs improved with 77% having excellent improvement

Answer 29

severity or progressive fail to respond to medical unremitting pain finances

Answer 30

Pros - remove disc easier - minimal muscle dissection - prophylactic fenesrtation cons - haemorrhage - poor field of view - reduced exposure for lateral/foramen disc

Answer 31

pros - provide increased decompression - better lateral access

Answer 32

modified paramedian approach: protect trachea, sheath and recurrent n. and reduce bleed from thyroid a. 33% length of vertebral body 50% width (but preferably 33%) excessive may lead to instability ad subluxation haemorrhage: cool avage, wax, gelatin sponge, macerated muscle | most residual compression post CT

Answer 33

Provides access at the site of herniation without removing a large portion of the annulus, thereby preserving more stability Window: 20% width and 20-25% length

Answer 34

9.9% complications, 6.4% of which are major Mean mortality 3-8% Respiratory compromise (**phrenic nerve C5-C7**) > hypovent + aspiration Cardiac dysrhythmmias (VPC) dt near sheath Haemorrhage (18.9%) Neuro deterioration > excessive manipulation, horners, layngeal paralysis Instability (8% when width 50%) seroma

Answer 35

dorsal multifidus elevated, pinous and yellow lig removaed laminectomy extended 75% not include articular process Hemi indicated in lateral disc

Answer 36

A: shoud prevent further extrusion therefore reduce recurrence H: 30% new disc materila into canal in TL - unable to check if V-slot may exacerbate bulging in Type II collapse of sublux (major controbutor to stability > not recommended if >30kg

Answer 37

Site: caudal to C3-C4 have poorer prognosis (likely included Wobblers) single vs lutli vlsot not affect outcome (Gou 2020) Degree of injury: LMN dysfunction, presence of VMF not predicitive non-ambulatory ~70% recovery Duration of disease: Able to walk within 96hr are likely to make a full recovery, dogs that do not walk within 2 weeks are likely to have residual deficits Type of Tx: 36% recurrency with conservative vs 5-10% surgical brazil: 10% recurrence v-slot 90% full recovery 1m and 98% (60% caudal in large breed) hemilam 80% at 12m, outcome better with Type I small breed than type II large breed hihger complication with v-slot but longer recovery wtih slanted slot, Hansen type II good and excellent in 47% and 32%

Answer 38

Interarcuate branch (IAB) is a vascular structure, particularly developed in C2-3 intervertebral space, forming a dorsal bridge that connects ventral venous plexi in the vertebral canal, forming a ventrodorsal triangle surrounding the spinal nerve root. when performing a laminectomy or hemilaminectomy, precise knowledge of those vascular structures is critical to prevent hemorrhage

Answer 39

On the basis of the results of the present study, we concluded that distraction-fusion of the C5-C6 vertebrae did not alter the IDP in the C6-7 (caudally adjacent) IVD in ex vivo cadaveric canine C4-T1 vertebral specimens without evidence of IVD degeneration. Although the limitations of this study precluded us from drawing any definitive conclusions regarding the complex pathogenesis of ASDis, IDP does not appear to play a major role in the early phase of the disease process while the IVD has no degenerative changes. Because degeneration alters the ability of nucleus pulposus to absorb forces, it is possible that the IDP in IVDs adjacent to vertebral distraction-fusion sites may increase in vivo as disk degeneration progresses.

Answer 40

incidence IVDD in cats 0.12 to 0.24%, compared with 2% in dogs Hansen type I disc disease and protrusions (Hansen type II Methods retrospective case series n=3 Results A routine ventral slot surgery without complication, neurological improvement in all Clinical Significance Ventral slot surgery good long-term outcome in for feline cervical intervertebral disc herniation. To avoid excessively wide slot > careful surgical planning was performed with preoperative measurement of the desired maximum slot dimensions

Answer 41

Prospective case-series. Sample Population: Thirty-two cervical pedicle screws (CPS) placed in 3 large breed dogs. The majority (29/32) of these screws were placed without evidence of vertebral canal breach (grade 0), whereas a vertebral canal breach <2 mm (grade 1) was detected in 3/32 screws. In a cadaveric study comparing the biomechanics of bicortical pins and monocortical screws with PMMA placed free-hand in the canine cervical vertebral column, 100% of bicortical pins violated the vertebral canal compared with a much lower incidence after monocortical screw fixation.32 The angles for ideal screw insertion are of limited use in dogs, because of conflicting reports, inter- and intra-breed anatomical variations, and rotational effects of both surgical positioning and intraoperative probing or screwing on vertebral alignment.14,33,34 Consequently, free-hand CPS placement in dogs is not recommended.14,33

Answer 42

Non-ambulatory: single 123 versus multiple 62 ventral slot Retrospective After surgery, 96.2% of the dogs reached ambulatory status. 36.8% residual neuro deficits time to recovery of ambulation and presence of residual neuro deficits not different between single vs multiple site ventral slot

Answer 43

Vertebral fixation does not affect recovery or recurrence (< 15 kg) (n = 303) The recurrence rates were 4.7% (n = 7) in the VF group and 4.3% (6) in the nVF group. 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 44

Video telescope operating monitor–assisted surgery 39 dogs V-slot Prospective study. No significant differences regarding the decompression, ventral slot width ratio, residual disc material, and sinus bleeding. No significant differences were found between the 2 groups regarding postoperative neurologic grade (P = .17).

Answer 45

Cadaveric study. Animals: Fifteen 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 46

rate of recurrent clinical signs following successful Sx or medical Tx of cervical IVDD. Retrospective. Recurrence = clinical signs or imaging complete initial recovery: medical 36/119 (30.3%), 83/119 (69.7%) - recurrence of clinical signs: 40/119 (34%) overall, 27/83 (33%) sx, 13/36 (36%) medical - imaging-confirmed recurrent extrusion: 24/40 (60%); 80% within 2 years of fx - medical most commonly same site - surgical most commonly adjacent disc - no difference in rate of recurrence with treatment types (small number of recurrences and lack of imaging confirmation)

Answer 47

no association between cord compression and neuro grade or recovery time caudal/cranial compression and recovery time - recovery: complete recovery at 10 days (77.2% overall) more likely with gr2 vs gr3 gr1,2,3 → faster recovery than gr4 - no significant difference in complete recovery rate at d30 - 77.2% by 10d, 15.8% (93% overall) complete recovery by 30d

Answer 48

distribution: 222/307 (72%) chondrodystrophic, 77/307 (25.1%) non-chondrodystrophic - disc-associated vertebral instability 45/307 (14.7%) - outcome: 295/307 (96.1%) recovery - associations: non-chondrodystrophic → older age, requirement for vertebral stabilization vertebral stabilization → male, caudal cervical site, non-chondrodystrophic - vertebral stabilization performed on the basis of apparent correction of mild compression on dynamic myelography

Answer 49

- 18/36 surgical, 18/36 conservative - site: C4-C5 most common, 3/36 T13-L1 - outcome: median time to ambulation: sx 6.6d (0-28d) vs conservative 5.9d (0-15d) - prognostic factors: intramedullary lesion length ratio on MRI associated with recovery - mortality 3/36 (8.3%) - 3/3 cardiac arrest – 2/3 immediate post-op - conservative tx no worse/better than sx - possibly due to liquid/gelatinous nature of HNPE

Answer 50

The vertebral height of the cranial aspect of the foramen in significantly smaller than small dogs, resulting in a funnel shaped vertebral foramen therefore cerase threshold of cumulative effects of structures encraoching on spinal cord | dober/g.dane have stenotic in caudal

Answer 51

**Vertebral canal stenosis = key static lesion** Pornounced torsion of the caudal cervical column leading to IVD degeneration (caudal cervical spine has three times more torsion than cranial) Protrusion of larger volume intervertebral discs **C6-C7, C5-C6 in 90%** leads to compression of spinal cord | middle age, large breeed

Answer 52

causing severe formaen stenosis dt joint OA and : Proliferation of the laminae dorsally Articular processes dorsolaterally Pedicles laterally +/- disc, lig.flavem hypertrophy **c4-c7 in 80%** | young, giant breed

Answer 53

**Apoptosis of oligodendrocytes** interfering with remyelination Significant reduction in monocyte chemoattractant protein/chemokine ligand 2 (MCP-1/CCL2) concentrations - Elevation of **IL6** - implicated in generation and propagation of chronic inflammation

Answer 54

Large breeds: 50/50 Giant breeds: 20% single site, 80% multiple

Answer 55

concept explains developemnt of CS based on experimental studies + proposed key mechanism in humans worsen or improve depending on position og vertebral column > cord more compressed with flexed or extnded > extension: 25% reduction of C4-7 diameter in dogs thus, combo of static and dynamic factors > no evidence that instability plays a role in most cases

Answer 56

instability = loss of ability of vertebral column to maintain normal amounts of displacment under physioloical loads

Answer 57

rads: not confirm **CT** good bone resolution, rapid, sedation may miss main compression site or not ID mutple due to decreased contrast resolution invasive with myelogram more useful for OACSM **MRI** best access spinal cord pathology inc. accurtae predict site/severity/nature of compression (de caost 2006) cord atrophy = poorer prognosis tractography to assess for dynamic component (traction, flex/extend) *concept of dynamic lesions subjectove and assessment method have not be standadarised (da costa 2000)

Answer 58

vwf helps platelt adhesion tp subendothelium, platelet aggregation and bind FVIII > deficiency reduced aggregation and primary haemostatic dz congenital or 3 types, tupe I most common in doberman where reduced [ ] of all multimers Dx: vwf antigen assay (eliza) sensitive + BMBT/genetic test Tx cryopreciptate w Vwf (effective within 30min, last 4hr)/FFp/desmopressin DCM: can be occult, therefore ECG + echo recommended

Answer 59

Conservative: - 54% improved - 27% static Surgery - 81% improvement

Answer 60

de costa: 20% worse vs 80% improve with sx 53% euthanised regardless if medical or sx non-diff in survival time (prob because slow progression) DACSM 1 yr MRI, OACSM 2yr MRI Tx: ex restrict/physio/nsaid or CCS

Answer 61

Decrease vasogenic oedema Protection from glutamate toxicity Reduction of apoptosis

Answer 62

- decompress and reduce recurrence - patient specific - consdier if >1 site - dynmic? - prosepctive studies to compare tehcniques > most literature based on surgeon preference - current evidence does not support instability as a factor - distraction-stabilise eliminate dynamic whch is prob presetn in all forms - pros/cons of surgery

Answer 63

Ventral slot (72%) Inverted cone Dorsal laminectomy (79-95%, 30% recurrence) increase obidity Hemilaminectomy

Answer 64

Pins and PMMA (73%) Screw Bar-PMMA PMMA plug (82%, long term 62%) Locking plate (73%) Distractible titanium cage polyetheretherketone (PEEK) cage with locking plates Traction screw with locking plates

Answer 65

**1. PMMA + Pins** single, increased failure if 2 v-slot then threaded positive profile pins, bone graft angles: 35 C5-6, 45 C7 monocoruical screw performed similar biomehcnically > reduced PMMA amount to reduce oeisiohageal irritation > modifications: corticcancellous bone to distract + u-shape wire spacer 71% sucess long term penetration risk 25-57% **6. disc arthroplasty** in humans no consensus aim to preserve all motion to reduce ASS (no fusion) probs: long-term lacking, high subsidence rate + still reduce IVD mobility

Answer 66

A technique to distract the spine while preserving moton - Allows direct decompression - Allows reestabishment of normal disc space with preserved motion to decrease risk of domino effect (adjacent segment disease) --

Answer 67

Discectomy, leaving approx 3-5mm of dorsal annulus intact Anchor holes in the adjacent vertebral end plates Bone graft into ventral disc space once PMMA has hardened A retention screw can help to prevent migration

Answer 68

- Neuro deterioration (70% after continuous dorsal laminectomy, up to 42% with ventral techniques) - Improper implant placement (25-57%) > check with CT - Domino effect (20%) da costa 2007 with distract-stable - laminectomy membrane - Implant failure (7.5-30%) - Collapse of IVD - Insufficient decompression 6/7 dobberman on PM - - **Recurrence 24%** (jeffery 2001) - mortality 0-6%

Answer 69

Spinal cord hyperintensity on T2W with concurrent hypointensity on T1W images

Answer 70

70-90% improve despite technique chosen in short term medical success in 50% no other factors affect outcome: duration, non-ambl Sx may not alter longterm outcome, though does appear to consistently improve outcome MST 36mth (de costa) if med or sx - prob due to progressive nature of the dz despite Tx (therefore deterioeation not necessarily due to sx fail) *more studies required on long-term, with increased power and more objective caution interpreting results of any Tx

Answer 71

Cysts originating from the zygapophyseal joints of the vertebral articulations and are located extradurally. Divided histologically into - synovial cysts (epithelial lining) - ganglion cysts (mucinous degeneration or articular cartilage)

Answer 72

Degenerative changes of the zygapophyseal joint

Answer 73

Dorsal laminectomy Hemilaminectomy Percutaneous cyst rupture with corticosteroid injection (humans) Must remove enture cyst and periarticular soft tissues to minimize risk of recurrence

Answer 74

Thoracolumbar synovial cysts: These cysts are seen in middle-aged and older large-breed dogs and usually cause unilateral spinal cord compression. caudal lumbar vertebral column/lumbosacral synovial cysts: Affected dogs are typically large-breed, middle-aged or older dogs, although lumbar cysts have also been reported in a 2-year-old Boxer.87,231 Clinical signs include pelvic limb lameness or weakness

Answer 75

A presumptive diagnosis of extradural synovial cysts can be achieved via imaging, with MRI being the imaging modality of choice. well-circumscribed extradural mass(es) on one or both sides of the vertebral foramen. hyperintense in T2W hypointensity, isointensity, or hyperintensity in T1W (depending on cyst contents)

Answer 76

compression that improves with with traction usually due to releif of compresion by AP or ligament, therefore inctease dural tube diameter expect to benefit from distraction-stabilisation sx de costa: MRI suggest that almost any compression whether static or dynamic will improve with traction >not based on evidence-based criteria >traction not standardised >cocept highly subjective according to current literature

Answer 77

10 dogs with (DACSM) and 1 dog with osseous-associated Design Retrospective case series. myelography with or without advanced imaging , Sx with C-LOX implant. Long-term follow-up was available in 8/11 with owner questionnaire. 2 euth. Seven (70%) dogs with DACSM improved neurologically but had persistent neurological dysfunction Postoperative radiographs revealed cage subsidence in 5 (50%) dogs, and loosening of a single cranial or caudal vertebral body screw in 4 (40%) dogs with DACSM. Five major complications occurred in 4 (40%) patients Adjacent segment disease occurred in three dogs (30%) with DACSM conclusion: comparable to previously described distraction–stabilisation techniques.

Answer 78

100 dogs with OACSM and MRI more than one site (78%) and foraminal stenosis (91%). Dogs with multiples sites > more likely to have severe spinal cord compression There was correlation (weak) between neurologic grade and severity of spinal cord compression disc degeneration in 80% extradural intraspinal cysts (25%) majority of dogs with severe imaging signs were < 3 years of age. > older dogs not have more severe imaging changes or clinical signs

Answer 79

transpedicular pin+PMMA vs transvertebral body polyaxial screw for cervical stabilisation, ex vivo - no significant difference in angular range of motion at C6-C7 between groups - significantly reduced vs intact spine regardless of method - no significant increase in ROM of adjacent vertebrae

Answer 80

instrumented cervical fusion for DA-CSM. MST 27 months. - titanium cage (SynCage-C) with 2x ventral locking plate augmentation - pain scores improved 9/9, neuro score 8/9 at median 27.4m (9-51) - bone ingrowth 79.5±14.3% → spinal fusion in 9/9 - complications: subsidence 1/9, 4/9 implant failure → 2/9 plate removal - adjacent segment pathology: 7/9 dogs Dogs have a natural lordotic position that increases the risk of ventral extrusion of intervertebral implants from shearing forces

Answer 81

neuro improvement: 18/37 immediate post-op, 28/37 at 6w, 25/25 at 3m (19/25 normal) - complications: 22/25 screw loosening/breakage, 15/25 subsidence, 4/25 revision - 3/37 mortality – gastric perf, cervical disc-extrusion, progressive cervical pain Clinical Significance short-term clinical improvement in 33/37 treated cases. The high incidence of screw loosening > new locking system was required. The C-LOX device seems to be a valuable alternative The absence of a control group > impossible to directly compare the C-LOX implant to other existing distraction–fusion techniques

Answer 82

1mg/kg injections - successful in 3 of 4 dogs. Dog which was unsuccessful was unclear if disc protrusion was the cause of the lameness. Successful cases required 2-3 injections prior to long term resolution of signs

Answer 83

ex vivo biomechanical properties titanium intervertebral cage +/- plates - placement of cage: increased disc height index vs post-discectomy restoration of ROM in flexion/extension, lateral bending, rotation restoration of elastic zone stiffness in flexion/extension - addition of plates → reduction of total ROM in flexion/extension, lateral bendingmore research is necessary Need more study on long term, the risk of cage migration, non-union and subsidence and bony ingrowth through the cage.

Answer 84

Application of the FITS device in combination with 2 ventral SOP™ locking plates and autogenous cancellous bone graft was associated with excellent outcomes in dogs treated for DAWS in this small case series Fifteen of the 16 dogs had significantly improved neurologic status (P =.01) at 6 weeks. Seven of the 16 dogs were examined at 24-36 months with 6 considered normal and 1 had mild ataxia. Postoperative radiographic intervertebral distraction was significant (P = .01). Radiographic bridging was recorded in 10/16 dogs at 6 weeks and in 7 dogs available for follow-up at 5-36 months. Computed tomography in 3 dogs at 24-36 months and postmortem with histology in 1 dog confirmed bone-bridging. Complications were not considered clinically significant and included implant loosening (2 dogs, both single plates) and minor end-plate subsidence (8 dogs).

Answer 85

kinematics of Fitzateur canine cervical-fusion system - combination locking pedicle screw-rod system + intervertebral spacer (traction screw) - intervertebral spacer increases stiffness of construct - Hettlich 2014 (with PMMA); Schollhorn 2013 (with locking plates) Fransson 2007 (intervertebral plug) - implant → significantly reduced motion at implanted site - concomitant (non-significant) increase at adjacent site (C6-C7)

Ch 31 Cervical vertebral column Flashcards

(118 cards)