2021 Exam Flashcards

Question

"Previous L3-S1 lumbar fusion, now with PI 50, LL 25, and 10cm SVA anterior to sacrum, what is LEAST invasive option to correct sagittal alignment?

a) L2-5 smith Pete osteotomies
b) L1-S1 laminectomy
c) L3 PSO
d) T10 VCR

"

Answer 1

"Debated. Consensus C. But, if xrays shows mobile disc segments, a may correct.

JAAOS. 2009. Sagittal Plane Deformity in the Adult Patient

SPO - 10 degrees per level

Posterior column is shortened and anterior column is lengthened
Requires mobile disc space or osteomized anterior fusion mass
The osteotomy hinges on the posterior aspect of the disc
Posterior pedicle screw instrumentation is required to maintain closure of the osteotomy
Do if need 4 - 7 cm of sagital correction)

PSO - 30 degrees per level (do if need >10 cm)

Posterior column is shortened without lengthening the anterior column

Pedicle subtraction osteotomy (PSO) provides greater sagittal correction than single-level opening wedge osteotomy and Smith-Petersen osteotomies, with the advantage of working at a single level and not having to resect the intevertebral disc.

Hinges on anterior cortex
Posterior pedicle screws are required 3 levels above and below
Indications

Sagittal balance greater than 10 cm
Shape, angular kyphosis
360 fusion along multiple segments

VCR (vertebral column resection) - 45 degrees per level

One or more vertebral segments is removed

Includes posterior elements, pedicles and entire vertebral body as well as disc above and below

Indications

Congenital kyphosis, severe sagittal plane deformity plus coronal plane deformity, spondyloptosis, resectable spine tumor

Vertebral column resection is a technically challenging procedure with significant complication rates, and should be reserved for patients requiring >45° of sagittal plane correction for sharp angular deformities.
VCR provides the greatest amount of correction among other osteotomy types with complete resection of one or more vertebral segments with posterior elements and entire vertebral body including adjacent discs

"

Answer 2

"C. Meets Vallier EAC criteria and trending in the correct direction. Plafond is staged because its a plafond and we are not in Vancouver.

Remember Vallier's paper states the bones, including pelvis AND spine can be treated within 36 hours if one of the thresholds are met.

"

Answer 3

"D. Decreased abduction"

Answer 4

"c. AVN

Chest strap – at nipples and should fit 2 fingers under to let baby breath
Shoulder strap - set level of strap
Anterior leg strap – this prevents extension and child should be in 90 to 100 degrees of flexion
Posterior leg strap – this limits adduction and should be 15 degrees back from max abduction → tensioned too much = risk of AVN

"

Answer 5

"

c. Scoliosis (30-80%)

orthopedic conditions

congenital scoliosis
Sprengel's deformity (30%)

medical conditions & comorbidities

renal disease (aplasia in 33%)
auditory issues (deafness in 30%)
congenital heart disease/cardiovascular (15-30%)
brainstem abnormalities/basilar invagination
congenital cervical stenosis

MRI to rule out intraspinal cord abnormalities

atlantoaxial instability (~50%)
adjacent level disease (100%)

degeneration of adjacent segments of cervical spine that has not fused is common due to increased stress

"

Answer 6

"a. Pulvertaft

If it says ""repair"" you should pick kessler

"

Answer 7

"Posterior decompression + debridement"

Answer 8

"Intermittent symptoms with no permanent deficits

JAAOS. 2009. Adult Isthmic Spondylolisthesis
○ Most adults with axial or radicular pain related to lumbar spondylolisthesis will improve with nonsurgical treatment. The mainstay of early treatment of these symptomatic patients is the judicious use of nonsteroidal anti-inflammatory drugs, along with modification of pain provoking activities and relative rest for 1 to 2 weeks. Muscle relaxants are helpful in some patients with greater pain. Narcotic analgesics should be used sparingly and for short durations in cases of severe pain.

More than 75% of adults with back and leg pain resulting from a pars defect and grade I to II spondylolisthesis will have successful outcomes using antilordotic bracing and activity modification for 3 to 6 months.

Epidural steroid injections may provide some relief of radicular symptoms, but they are unlikely to help patients with axial pain.

Patients with persistent symptoms typically remain active and neurologically stable, even in the presence of high-grade spondylolisthesis"

Answer 9

Cast in full extension and in pronation

Answer 10

"4. Vancouver paper

Treatment failure, neurological deterioration, and persistent pain occurred more frequently in patients treated nonoperatively versus patients treated with surgery.
Surgical patients experienced infections and surgical related complications not experience by those managed nonoperatively.
Patients treated surgically after failed nonoperative management also experienced better outcomes than those who continued to be managed nonoperatively.
"

Answer 11

"Brown Sequard, central cord, anterior cord"

Answer 12

Fibrous dysplasia?

Answer 13

"20

Absolute Risk Reduction: Control Event Rate - Exposure Event Rate
= 0.1 - 0.5
= 0.05

NNT = 1/ARR
= 1/ 0.05
=20

"

Answer 14

"Plate stiffness can be decreased by far cortical locking

■ Far cortical locking (FCL) is an approach requiring specialized screws in a locking plate. FCL aims to reduce stiffness whilst maintaining strength of a construct. The screws have threads at the tip and the head that lock into the plate and far cortex respectively. The screws also have a shaft with a reduced diameter, allowing for movement at the near cortex due to an increased working length.

"

Answer 15

c) Present results as is

Answer 16

"Pelvic have higher recurrence

However, loaded question

■ JAAOS 2021

● The risk of malignant transformation of benign cartilage tumors has not been well established, and estimates vary widely. For solitary osteochondromas, the risk is most likely <1%,whereas patients with HME may have a 2% to 4% chance of developing chondrosarcoma. Patients with Ollier disease and Maffucci syndrome appear to have an even higher risk, with estimates ranging from 10% to 40%. One study suggested that malignancy is a near certainty in persons with Maffucci syndrome. Well-controlled, longitudinal, epidemiologic studies are needed to determine accurate estimates.

But, JAAOS 2010 Secondary Chondrosarcoma

○ Secondary chondrosarcoma is a distinctive type of tumor that originates from a preexisting cartilaginous lesion. Most commonly, it is associated with solitary or multiple osteochondromas. A fraction of cases arises from other conditions, such as Maffucci syndrome and Ollier disease. A sudden increase in the size of the cartilaginous cap of an osteochondroma is a sign of malignant transformation to secondarychondrosarcoma. However, there is no strict cutoff in terms of thickness of the cartilaginous cap that can be regarded as being pathognomonic of malignancy. Most cases of secondary chondrosarcoma are low to intermediate grade. Distant metastasis is uncommon, and the prognosis is good for most patients. Overall survival at 5 years is approximately 90%. Surgical resection with wide margins is the best treatment option, but local recurrence remains a significant problem in approximately 10% to 20% of patients. Patients with secondary chondrosarcoma of the pelvis are especially at risk for local recurrence.

Joe says stick with the JAAOS last sentence: Patients with secondary chondrosarcoma of the pelvis are especially at risk for local recurrence.

"

Answer 17

"Repeat. Clotting

JBJS 2008 review Kienbock's disease
Precise etiology not known
Kienbock's seen in sickle cell causing bone infarction
Necrosis might be consequence of impaired venous outflow or arterial interruption
""Some lunates may be predisposed to collapse because of their particular anatomy causing an uneven internal distribution of the bone stresses""
Uncovering of the lunate by the distal radius, ulnar negative variants, midcarpal facet on the lunate, radial inclination
"

Answer 18

"2. Poor complianc

Loads of references including several different JAAOS reviews on the topic of clubfoot
Most if not all state that full time boots and bars required for three months followed by 12hrs/day until age 2-4 for maintenance of correction

Treatment of relapsed deformity in the older child begins with repeat ponseti casting
"

Answer 19

"standing to sitting will cause anterior tilt of pelvis = FALSE

PI=PT+SS

When the patient sits, lumbar lordosis decreases and the pelvis “rolls back”
- Opens the acetabulum to accommodate flexion and internal rotation of the hip
- This protects from anterior impingement and posterior hip dislocation

"

Answer 20

"Compartment reading 40mm Hg, and diastolic BP 75mm Hg. Delta is 35... We picked 4 as a consensus as there is evdience to support delta P greater than 30.

JAAOS 2020 - Management of Acute Compartment Syndrome (CPG Summary)

- In obtunded patients, the workgroup found no evidence regarding the utility of the clinical examination in diagnosing ACS. Therefore, the workgroup's consensus was that pressure-based methods of diagnosis be used.

JAAOS 2021 - Diagnosis and Management of Acute Compartment Syndrome

- No physical examination finding or diagnostic test has 100% specificity and sensitivity for ACS, and diagnostic criteria will likely vary based on patient factors (ie, intoxication or the obtunded patient).

JAAOS 2011 - Acute Compartment Syndrome of the Upper Extremity
- ACS is typically diagnosed clinically. However, it may be necessary to measure compartment pressure (Figure 6). Animal studies demonstrate that compartment syndrome is indicated in the presence of a difference between diastolic blood pressure and the compartment measuring ≤20 mm Hg40 or a difference between mean arterial pressure and the compartment measuring ≤30 mm Hg

- Fasciotomy is often performed in patients with absolute pressure measuring >30 mm Hg.6. We consider a differential between diastolic pressure and the compartment of ≤20 mm Hg to be an absolute indication for emergent fasciotomy. In the patient with swollen compartments and nearly normal pressures (<30 mm Hg absolute pressure), we advocate waiting and performing serial examinations and pressure measurements. Increasing swelling and rising pressures warrant decompression even when the pressure differential is ≤20 mm Hg

- This is a tricky question because the compartment pressure of >40 is obviously concerning but in previous years it seems that the delta P of <30 is more important and in this question the delta P is 35

Old version (from 2003-2007 doc): An adult with a head injury who is unconscious with multiple injuries with a T2 spinal fracture for which he is paraplegic. He also has a tibia fracture. The most appropriate criteria for diagnosing a compartment syndrome is:

○ Calf swelling

○ Pain on passive toe movement

○ Compartment pressures of 40mmHg with a blood pressure of 120/80

○ Compartment pressures of 30mmHg with a blood pressure of 100/50

"

Answer 21

"

a. Should not cross physis with screws

JAAOS 2013 - Pediatric Physeal Ankle Fractures

○ A = FALSE

■ Because there is minimal to no growth remaining, fixation that crosses the physis is unlikely to cause complications. Bioabsorbable implants also can be used.¹ These patients are near the end of growth and physeal function, and thus, the risk of physeal damage with resultant deformity is low.¹⁷

○ B = TRUE

■ Patients with nondisplaced fractures are treated with 4 weeks in non-weight-bearing long leg casts applied in internal rotation, followed by non-weight-bearing in a boot for 2 weeks

C = TRUE ** (Don't let JAAOS typo screw it up)
Wuerz et al 2013 JAAOS
Produced experimentally by everting a supinated foot - ATFL avulses with ER
--> So I think the issue here is they wrote anterior tibiofibular ligament instead of anterior inferior but they are the same thing because ATFL means “talofibular”

○ D = TRUE

■ CT is warranted in cases in which displacement >2 mm is suspected (Figure 6). CT better defines fracture displacement and can aid in surgical planning. displacement and can aid in surgical planning.

"

Answer 22

"A or B

A = Consensus 2022 document

● JAAOS 2008 - Degenerative Lumbar Spondylolisthesis: Trends in Management

○ Non-op management for mild symptoms, not sure about the follow up time frame, but given that it’s a higher grade slip I suppose that’s why people settled on the 3 month follow up, I honestly feel like A is a better option, sigh

○ Jen looked back further and found this repeated again in 2003-2007 doc, in that one they picked A and cited this paragraph from the same article

■ Listhesis has been shown to progress in 25% to 30% of patients, but it rarely progresses to >30% of the subjacent vertebra. In their study of the natural history of listhesis, Matsunaga et al reported that back pain improved as the disk space was collapsed and that progression of the slippage occurred in only 34% of patients. 76% percent of the patients who were initially neurologically intact did not deteriorate over time. Such patients may be treated nonsurgically. Conversely, most patients (83%) with a history of significant neurogenic claudication or vesicorectal symptoms deteriorated and had a poor outcome. These patients should be treated surgically.

● JAAOS. 2009. Adult Isthmic Spondylolisthesis

○ Most adults with axial or radicular pain related to lumbar spondylolisthesis will improve with nonsurgical treatment. The mainstay of early treatment of these symptomatic patients is the judicious use of nonsteroidal anti-inflammatory drugs, along with modification of pain provoking activities and relative rest for 1 to 2 weeks. Muscle relaxants are helpful in some patients with greater pain. Narcotic analgesics should be used sparingly and for short durations in cases of severe pain. More than 75% of adults with back and leg pain resulting from a pars defect and grade I to II spondylolisthesis will have successful outcomes using antilordotic bracing and activity modification for 3 to 6 months.^27-29 Epidural steroid injections may provide some relief of radicular symptoms, but they are unlikely to help patients with axial pain. Patients with persistent symptoms typically remain active and neurologically stable, even in the presence of high-grade spondylolisthesis

"

Answer 23

"1. Presynaptic ACH prevention

"

Answer 24

"Idiopathic curves will correct with lumbosacral arthrodesis. Incorrect

● BOTTOM LINE:

○ Pts with idiopathic scoliosis have a LOW INCIDENCE of spondylolisthesis

○ Pts with spondylolisthesis have a HIGH INCIDENCE of scoliosis

○ Idiopathic curves do not correct after fusion

○ Postural curves do

"

Answer 25

"Humeral version

JBJS - periprosthetic humeral fractures during shoulder arthroplasty
Athwal et al (western)

a relative risk analysis- female patients were three times more likely to sustain fractures than male patients; patients undergoing revision surgery were three times more likely to sustain fractures than patients undergoing a primary TSA
press-fit humeral component three times more likely to lead to a fracture than cemented humeral component was, and patients with posttraumatic arthritis were two times more likely to sustain a fracture than patients with a diagnosis of rheumatoid arthritis, osteoarthritis, or osteonecrosis

Patients who were managed with a primary press-fit humeral component had a significantly higher likelihood of sustaining an intraoperative fracture than did patients who were managed with a cemented component (relative risk, 2.9; p = 0.046)

The fracture rate based on the primary diagnosis was 1.2% (relative risk, 0.8; p = 0.58) for osteoarthritis, 1.1% (relative risk, 0.7; p = 0.67) for rheumatoid arthritis, 2.5% (relative risk, 1.9; p = 0.11) for posttraumatic arthritis, and 1.6% (relative risk, 1.1; p = 0.75) for osteonecrosis

"

Answer 26

"

1. Increase lateral compartment pressure

STABILITY study – Getgood et al (Western), American Journal of Sports Med

Addition of LET to single-bundle hamstring autograft ACLR in young patients at high risk of failure decreased graft rupture and persistent laxity at 2 years (NNT 14).

Remember, worse 3 month outcomes as its a bigger surgery.

Lateral Compartment Contact Pressures Do Not Increase After Lateral Extra-articular Tenodesis and Subsequent Subtotal Meniscectomy – Tomoyuki Shimakawa – Ortho J Sports Med, 2019

"

Answer 27

"AITFL no effect on posterior translation of fibula

Biomechanical analysis of the individual ligament contributions to syndesmotic stability
Clanton et al F&Ankle international 2017
AITFL provides clinically significant stability to the syndesmosis
resistance to posterior fibular translation and external rotation of the lateral malleolus when an external rotational force is applied
The PITFL also provides a significant, but smaller, contribution to stability, primarily providing resistance to internal rotation

JAAOS 2021 Diagnosis and treatment of syndesmotic unstable injuries
AITFL primarily limits external rotation of the fibula, and biomechanical studies suggest that isolated injuries to the AITFL result in approximately 24% reduction of resistance to external rotation
The IOL prevents coronal plane translation of the fibula, esp during ankle dorsiflexion
PITFL extends from the posterior tibial tubercle to the fibula and limits posterior translation of the fibula

"

Answer 28

"Osteoporosis in post menopausal women is defined as a T score less than 1.5. INCORRECT.

Osteoporosis defined as T-score below -2.5 per WHO. This means compared to the average 30 YEAR OLD.
50% of patients over the age of 80 will have osteoporotic vertebral compression fractures
Osteomalacia/rickets = metabolic bone dz where defective mineralization results in a large amount of unmineralized osteoid
"

Answer 29

"Monostotic has high recurrence rate

JAAOS review - langerhans cell histiocytosis - the great imitator

LCH has a wide spectrum of disease that can range from focal disease (eosinophilic granuloma) that can be benign or fatal depending on the involvement
- Localized form (EG) accounts for 70% of cases

Unknown exactly what it is - neoplastic vs autoimmune

Three forms with monostotic having the best prognosis

Single focus, single site (monostotic EG) - self limiting - 100% 10 year survival --> Lesions have been seen to resolve after simple needle biopsy; can inject steroid at the time of needle biopsy
Single system, multisite (Polyostotic EG) - 90% 10 year survival - consider chemo
Multisystem - 70% 10 years survival

After bone, skin is the second most common location for lesions; can also see solid organ inc lung involvement (more common in smokers)

Radiologically appears as a lytic bony lesion that can be permeative or well define

"

Answer 30

Stress shielding

Answer 31

"C. Repeat

Hand Clin 31 (2015) 399–408. Perilunate Dislocations and Fracture Dislocations
JAAOS September 2011, Vol 19, No 9. Perilunate Dislocation and Perilunate Fracture-dislocation
Less arc injuries involve ligament injuries around the lunate, compared to greater arc injuries which involve bony injuries (trans-scaphoid, trans-radial etc).

Mayfield classification describes sequence of disruption during injuries around the lunate which progress from SL dissociation (SL ligament disruption), lunocapitate disruption (disruption through the space of Poirier) to lunotriquetral disruption which results in a perilunate dissociation (dorsal radiocarpal ligament fails, lunate rotates volar attached to the intact volar radiolunate ligament).

** The space of Poirier Is an area of weakness at the level of the proximal capitate between the volar radioscaphocapitate ligament and volar long radiolunate ligament where the lunate will escapes into.

"

Answer 32

" c) Counseling TAA - WRONG

Ideal candidate
o Lower BMI
o Female
o 60
o < 30 degrees malalignment
o Preserved ankle motion

· Contraindications
o Young active
o Active infection
o Significant malalignment
o Charcot"

Answer 33

"d) Kyphosis deformity more common in lumbar spine

JAAOS: September 2015, Vol 23, No 9. Granulomatous Vertebral Osteomyelitis
JBJS: 2020 Apr 1;102(7):617-628 .Concepts Review: Tuberculosis of the Spine

Three major patterns of spread have been described: peridiscal, central and anterior. Peridiscal is most common, where it begins at an endplate, and then spreads to the disc. Spreads to adjacent levels deep to ALL. Central pattern involves abscess in the vertebral body which leads to collapse and deformity. Anterior involves abscess anterior to vertebral body that spreads to multiple levels under ALL, causing scalloping and multilevel abscesses. TB doesn’t have proteolytic enzymes, so it doesn’t tend to destroy the disc space as much as other infections.

Distinctive MRI findings include contiguous VB involvement with preservation of disc spaces, marrow edema, prevertebral and paravertebral septate loculated collections, subligamentous collections, end-plate erosions, and intraosseous abscess with epidural extension.

The VBs in children are cartilaginous and highly susceptible to rapid destruction. VB cartilage loss produces severe deformities in active disease. Asymmetrical loading affects the growth potential differentially, leading to the development and/or progression of the spinal deformity with growth.

Fever and less duration assx with pyogenic vs TB

Stupid at risk signs

"

Answer 34

"Don't get this

b. Botox and serial casting vs. casting shows no difference

facts:
1. botox has been shown to improve equinus gait and passive ROM
2. botox>casting in dynamic contractures
3. casting>botox in fixed contracture
4. when comparing botox alone vs casting alone vs botox + cast, botox alone has worse outcomes)

Contrary to our hypothesis, the addition of botulinum toxin A to a serial casting regimen led to earlier recurrence of spasticity, contracture, and equinus during gait. The results of the present study suggest that botulinum toxin combined with serial casting for the treatment of fixed contractures will lead to a recurrence of plantar flexor spasticity and equinus contracture by six months in this patient population. (JBJS 2004)

"

Answer 35

"C) You need CT scan before the initial surgery

JAAOS: October 2011, Vol 19, No 10 Pilon Fractures: Advances in Surgical Management

“Clinical series from the mid 1980s through the early 2000s using immediate ORIF indicate wound complication rates of up to 100%”. Therefore, a staged approach with initial ex fix with or without limited fixation of the fibula is now the standard of care which has been shown to limit soft tissue complications.

“Many surgeons perform fibular ORIF at the time of external fixation to gain length and align the tibia”.

“Obtaining a CT scan after initial ankle spanning external fixation improves fracture fragment visualization secondary to ligamentotaxis.”

“Definitive ORIF is generally recommended following resolution of soft-tissue injury. This is indicated clinically by resolution of ecchymosis over the intended surgical site, re-epithelialization of fracture blisters, healing of open fracture wounds without infection, and resolution of soft-tissue edema sufficient to allow the skin to wrinkle (ie, wrinkle test) (Figure 3, A). Typically, this occurs 10 days to 3 weeks after injury.”

"

Answer 36

"Arcade of Struthers

Pronator syndrome originally referred to compression of the median nerve between the two heads of the pronator teres.

Patients present with sensory symptoms similar to CTS. These patients also complain of aching pain in the proximal volar forearm and have sensory loss in the distribution of the palmar cutaneous branch of the median nerve (thenar eminence).

Patients will have a positive resisted FDS middle finger test; pain or paresthesia with resisted flexion of the long finger FDS is suggestive of median nerve compression at the level of the fibrous arch between the heads of the FDS. Some now refer to this as Lacertus syndrome"

Answer 37

"No palpable pulse is a contraindication for surgical treatment.

If pulse is not palpable (usually is in Charcot foot) then you get further studies to assess perfusion and see if vasculopathy needs to be addressed first

J Foot Ankle Surg 2019 Sep;58(5):1030-1035.

doi: 10.1053/j.jfas.2019.01.004.

Plantar Approach for Midfoot Wedge Resection to Reconstruct the Rocker Bottom Foot

Justin D Persky¹, Travis Langan², Clair N Smith³, Patrick R Burns⁴An 87% limb salvage rate (26/30) was demonstrated

"

Answer 38

"Able to abduct fingers (T1)

Remember its shooting a basketball:

Cock elbow (elbow flexion C5), cock wrist (wrist extension C6), start shot (extend elbow C7) and relase ball (wrist flexion C7), follow through (finger flexion C8), watch swoosh (abduct fingers T1)

C6 – sensation to thumb, wrist extension
C7 - triceps and wrist flexion, and triceps reflex
C8 – DIP flexion
T1 – hand intrinsic (intrinic’s)

"

Answer 39

"a) halovest in minimally displaced fractures

The management of odontoid fractures remains relatively controversial, specifically when treating Type-II fractures in the aging population.

· Halo vest immobilization should also be used carefully in patients >65 years of age given the conflicting evidence for increased mortality, secondary to pulmonary complications, with mortality rates as high as 21% to 40% across the literature
· Traditionally, the only option for odontoid fracture treatment had been a posterior approach and arthrodesis of C1-C2

"

Answer 40

"heals slower than normal

https://posna.org/Physician-Education/Study-Guide/Osteogenesis-Imperfecta

OI is a qualitative and quantitative disorder of collagen 1 that leads to multisystem involvement including eyes (blue sclera, lens subluxation/dislocations, discoloration of teeth, hearing loss, joint hypermobility, and recurrent fractures that often die of cardiac valve insufficiency / aneurisms. The incidence of scoliosis in the population with OI varies from 39% to 80%. Bracing is contra-indicated in OI due to risk of fractures (especally ribs)

The severity depends on the mutation and dictates when it is diagnosed, with severe mutations causing death as an infant. Fractures heal with normal time but they don’t have enough time to remodel before the bone breaks again. Fracture healing is unaffected in patients with OI and therefore the duration of immobilization should not be extended. Once this deformity occurs, it becomes a natural stress riser and then they have a worsening deformity.

fractures also don't have enough time to remodel, so that angular deformities occur"

Answer 41

"c) Between EPL and ECRB

https://surgeryreference.aofoundation.org/orthopedic-trauma/adult-trauma/forearm-shaft/approach/approaches-to-the-radius-for-intramedullary-nailing#introduction
The correct nail entry point and so the chosen approach depends on the nail type used. The following entry points are used:
On the ulnar side of the radial styloid, between the first and second extensor tendon compartments
On the radial side of the Lister’s tubercle, between the second and third extensor tendon compartment

"

Answer 42

"b) Obturator nerve

https://surgeryreference.aofoundation.org/orthopedic-trauma/adult-trauma/acetabulum/approach/modified-stoppa-approach#deep-dissection

At this level, the obturator neurovascular bundle is crossing the quadrilateral surface. In most cases it should be mobilized. A spatula or malleable retractor is used to protect the obturator neurovascular bundle and pelvic floor.

The SI joint is better seen through the lateral window

"

Answer 43

"Will progress after 1 year when they begin to sit

Also, lets bring back the favorite table

And foot deformity..

L1-2 = equinovarus

L3 = equinovarus – resting position of foot

L4 = cavovarus – tib ant works - causes cavus

L5 = calcaneovalgus – peroneals and edc

Level denoted means that that level is the last one that works

"

Answer 44

"b. Pulsed lavage, suction, dressing change

High risk: Power drills, reamers and high-speed saw, High-speed burr, Pulsed lavage, Electrocauterization, Lasers

"

Answer 45

"Tibial component perpendicular to tibia axis (coronal)

Black Book:
Tibia component
1. Horizontal tibia cut should be minimal and match the native tibial slope. Some say <7 to protect ACL
2. Sagital cut should be as close to tibial spine as possible
3. Tibial component should be perpendicular to long axis of tibia in coronal plane
4. Avod undersizing tibia - this can cause fracture or subsidence
5. Avoid posterior cortex penetration

"

Answer 46

Repeat. 50%

Answer 47

"Medial eminence resection with osteotomy 2mm lateral to the medial groove of the metatarsal head.

Iatrogenic causes (all play a role..)
- Loss of osseous support
· Excessive medial eminence resection
o Excision of fibular sesamoid
· Formerly done in the classical description of the McBride
· Compromises stability of lateral structures and removes fulcrum of rotation for lateral head of FHB
o Muscle imbalance at base of proximal phalanx
· Release or attenuation of adductor hallucis and lateral head FHB with over release of lateral capsule
· Allows overpull of medial muscles (medial head FHB and abductor hallicus)
o Overcorrection of IMA
· Can allow vector of medial deforming forces to cause varus
o Overcorrection of hallux varus interphalangeus
· i.e. excessive Akin
· Again, turns EHL and FHL into deforming forces
o Excessive medial capsulorrhaphy
o Aggressive post-op bandaging

"

Answer 48

"Osteoblastoma

Other vesions had ""most common primary bone tumor in the skeletally immature..."" which may think ewing's"

Answer 49

"C5

No difference between anterior and posterior (some say higher in front)
Mechanism is controversial, may be due to tethering of nerve root with dorsal migration of spinal cord with removal of posterior elements

"

Answer 50

"b) Little finger 40 °"

Answer 51

"Debated....may have recall issues

Principles of Teardrop Angle

● With a dorsal barton’s the teardrop angle will likely not change UNLESS there is associated volar comminution

● Volar comminution does not necessarily occur with a dorsal barton’s but it can as in this example

● If volar comminution does occur with dorsal barton’s then the teardrop angle would be decreased.

● In a volar barton’s the TDA is typically increased.

● This years stem says “increase” so the answer is wrong, in 2016 we had recalled it as “can cause a change” which would technically be right, hence the controversy

Likely A

"

Answer 52

c. Leads to early Ulnohumeral OA

A - LUCL ruptured
B - Does not typically haver radial head fracture
C - Yes
D - Involves the AMF

Answer 53

"b. Saltzman

"

Answer 54

"protect the mechanical stability of the whole bone with implant"

Answer 55

"d. High specificity

The electronic literature search returned 2212 records, of which 13 articles were eligible. Among 8 tests included in the systematic review, the lift-off test was most frequently reported (12 studies). Four tests were eligible for meta-analysis: bear-hug test, belly-press test, internal rotation lag sign (IRLS), and lift-off test. The highest pooled sensitivity was 0.55 (95% CI, 0.28-0.79) for the bear-hug test, while the lowest pooled sensitivity was 0.32 (95% CI, 0.13-0.61), for the IRLS. In all tests, pooled specificity was >0.90.
"

Answer 56

"Repeat.Is oliguric with maintained salt excretion.

Many post-spinal surgery pts have an ADH surg causing low urine output in a euvolemic state. Can progress to SIADH ( UO <1mm/kg/hr, serum Osm <280, urine Osm > 249, Serum Na <131).
"

Answer 57

Lateral meniscus

■ Vascular injury - Shatzker 4

■ Lateral meniscus - 2

■ Medial - 4

■ ACL - 4, 6

■ Peroneal nerve - anterior dislocation

■ Popliteal A - posterior dislocation

■ LCL - 4

Answer 58

"Internal carotid

"

Answer 59

"Elongation of muscle while muscle increases tension

JAAOS 1999 - Muscle Strain Injury
Forcible stretching of a muscle…most often during an eccentric contraction when the muscle is being lengthened as it contracts
Generates higher forces than concentric"

Answer 60

"NF1 - Malignant peripheral nerve sheath tumor

Malignant Peripheral Nerve Sheath Tumors:

Most severe neoplastic complication
Elusive, wide metastases and high rate of local recurrence
Poor prognosis (5 year survival 21%)
Lifetime risk is 10-24%
Usually originate from plexiform neurofibromas

Usually 10-20 years after their development

Clinically have increasing pain, enlargement and new neurological deficits

Can be a very difficult diagnosis to make
First step = MRI

Note, previous exams have said ""CENTRAL"" which was incorrect"

Answer 61

"B. Elbow flexion

JAAOS 2012 Lee, Wolfe

Authors order of importance for restoration:

Elbow flexion
Shoulder abduction and ER
Scapular stabilization
Elbow extension
Sensory reinnervation to control neuropathic pain
Restoration of below-elbow function

Restore elbow flexion with a oberlin - ulnar nerve to biceps transfer.

"

Answer 62

"

C. Semimembranosus

JAAOS December 2019

In contrast, proximal hamstring avulsions typically occur during eccentric contraction with the hip flexed and knee extended, putting the muscle on maximum tension.

The semimembranosus origin is the least likely to rupture, and its intact tissue can help prevent notable tendon retraction

Conjoined tendon = semiT and biceps. Semi M is more lateral.

Anatomic location
- myotendinous junction
  - is the most common site of rupture in adults
  - often occurs during sprinting
- avulsion of ischial tuberosity
  - less common
  - seen in skeletally immature
    10% of all pelvis avulsion fractures in the skeletally immature
  - seen in water skiers
tendon repair
- indications
  2 tendons with at least > 2 cm retraction in young, active patients
  3 tendon tears

"

Answer 63

"D. Post op instability

JAAOS 2017
In a review of the Norwegian Arthroplasty Register, Lie et al36 compared the results of groups treated with liner exchange (318 hips), exchange of well-fixed components (398 hips), and loose acetabular components (933 hips). The authors found that the risk of acetabular revision was highest in the liner exchange group, and instability was the most common reason for revision.

"

Answer 64

"B, debated with D in 2022 consensus document.

OKU Shoulder and Elbow 2017
Recent anatomic studies by shoulder surgeons revealed that the supraspinatus inserts onto the limited anterior most portion of superior facet and even onto the lesser tuberosity

"

Answer 65

"C. Left C7-T1 disc herniation

C7-T1 disc would affect C8 nerve, C8 sensory distribution fits with description
MABCN innervation forearm sensation, differentiates from ulnar nerve neuropathy

"

Answer 66

"Repeat.
Static: (top 3 most important) - RC EXAM
LCL
Popliteus Tendon
Popliteofibular ligament
Lateral Capsule
Variable --> arcuate ligament, fabellofibular ligament
"

Answer 67

"

C. Recurrent laryngeal nerve

Runs between the trachea and the esophagus and loops around the aorta on the left and subclavian on right
If doesn't get better after 6 weeks, consult ENT larynoscopy

1-2 percent

Increased when operating from the right (subclavian on the right)
Increased the most distal the level

Old questions say this is the most common complication post op (dysphagia), most get better

"

Answer 68

"

c. Forefoot Plantar Ulcers, Plantar fasciitis, midfoot charcot

JAAOS 2013 – Triceps Surae Contracture

“Strong association with metatarsalgia, neuropathic ulceration, plantar fasciitis, Charcot midfoot breakdown”
“Lesser degree PTTD, Achilles tendinopathy, ankle sprain and fracture, MTP synovitis, hallux valgus, claw toes and toe walking”

"

Answer 69

"c. There will be no major complications if the patient is taken to the OR before 24-48 hours

CPG from JAAOS 2018 state the following: Evidence supports not delaying hip fracture surgery for patients on aspirin and/or clopidogrel (recommendation level limited))

2014

The Effects of Clopidogrel (Plavix) and Other Oral Anticoagulants on Early Hip Fracture Surgery. Collinge et. al. JOT. 2012
Clopidogrel is different from other anticoagulants because no physiologic method of reversing the antithrombotic effect of this medication is known. Platelet transfusions have been attempted but have not been effective in reversing the effect of clopidogrel. The effects of clopidogrel on platelet aggregation are thought only to be completely reversed within 7 days of the last dose by production of new platelets.
No significant increase in bleeding parameters or complications was observed in patients taking clopidogrel compared with those not on clopidogrel.
The present investigation suggests that patients on clopidogrel who underwent early open operative treatment of a hip fracture did not have increased clinically significant risk for blood loss, transfusion requirement or perioperative complications compared with those patients not taking the medication."

Answer 70

"d. 20% late conversion to THA

Gull wing on the iliac oblique - medial acetabulum roof that occurs with anterior and posterior hemitransvere ---> (represents superomedial impaction)
Stoppa Ilioinguinal most common

"

Answer 71

"Debated on many exams. Depends on stem but this question:

b. Do surgery and discuss with patient and family after

2014
The CPSO website does not mention need for a second surgeon's opinion.
From CMPA best practices website:
In urgent situations, it may be necessary or appropriate to initiate emergency treatment while steps are taken to obtain the informed consent of the patient or the substitute decision-maker, or to determine the availability of advance directions. However, the instructions as to whether to proceed or not must be obtained as quickly as practicably possible.
When an emergency dictates the need to proceed without valid consent from the patient or the substitute decision-maker, a contemporaneous record (at the time) should be made explaining the circumstances which forced the physician's hand. If the circumstances are such that the urgency might be questioned at a later date, arranging a second medical opinion would be prudent if possible.
"

Answer 72

"b. It is uncommon for the Prox Tib fib joint to communicate with the femortibial space

A - False - Anterolateral dislocation is the most common dislocation of the proximal tibiofibular joint

B - True - The proximal tibiofibular joint is a synovial membrane-lined, hyaline cartilage articulation that, in 10% to 12% of people, communicates with the knee joint.

C - False - The proximal tibiofibular joint allows for the external rotation of the fibula that naturally occurs with ankle dorsiflexion.

D - False - As a result of the laxity in the joint capsule with flexion, injuries to this joint generally occur with the knee in a flexed position.

"

Answer 73

Similar infection similar nonunion

Answer 74

Associated with fascial hernias

Anterior compartment more common location

Risk factors

Creatine supplementation
Androgenic steroids increases muscle volume throughout the body...has been implicated as a potential cause of abnormal intracompartmental pressures in exercising athletes
Eccentric exercise in postpubertal athletes may decrease fascial compliance over time, and in those congenitally predisposed, create a favorable environment for CECS

Investigations

Compartment measurements

Three phases: rest, 1 min post exercise, 5 or 15 min post exercise
Diagnosis

Resting > 15 mmHg
1 min post > 30 mmHg
15 min post > 20 mmHg
30 min post > 15 mmHg

Answer 75

"Repeat

b. 60% of patient with fractures have vit D def

Health Canada has suggested that the adequate intake of vitamin D for adults 19 to 50 years of age is 200 IU/day, those 51 to 70 years of age is 400 IU/day and those 71 years of age and older is 600 IU/da"

Answer 76

"Cer on cer = fluid film lubrication

● JAAOS 2018 - Bearing Surfaces for Total Hip Arthroplasty

○ Polyethylene bearings are described as having either a boundary lubrication regime, in which substantial contact exists between surface asperities, or mixed lubrication, in which the load is balanced between contacting surface asperities and the lubrication fluid.

■ A = FALSE

○ MoM implants are unique in that larger femoral head sizes (≥36 mm) have been shown to improve lubrication by establishing a fluid-film regime, and smaller head sizes (≤28 mm) establish a boundary or mixed lubrication regime

■ Metal on metal has fluid film only for heads bigger than 36mm so B = FALSE

○ Ceramic-on-ceramic implants, given the nature of their smoother surfaces, have the best lubrication performance and can establish fluid-film lubrication at various femoral head sizes.

■ D = TRUE and therefore C = FALSE

"

Answer 77

"Recall issue here. Consensus is 3.

FDP 2-5 - dual innerv AIN & Ulnar
Lumbricals 2-5 - dual innerv med&ulnar
FPB - dual innerv: median (mostly)&ulnar
APL - PIN

LOAF - median
1 / 2 lumbricals
opponens pollicis
APB
FPB

"

Answer 78

"A. 6 year most common (debated), may of been mis-remembered as JAAOS quotes less than 5

But we all agree that 80 percent is too high and some literature says 2 - 10. Xray changes seen later.

● JAAOS 2003 - Childhood Diskitis

■ Less than age 5

■ Lumbar spine most common

■ 60% get a bug. Staph A. most common

Radiographs

● radiographic findings are unreliable

● earliest manifestation is at 1 week

findings

○ usually normal radiographs early in process

○ loss of lumbar lordosis may be earliest radiographic sign

○ disc space narrowing (10-21 days after infection begins)

○ endplate erosion (10-21 days after infection begins)

"

Answer 79

"Will have the exiting nerve root - L4. Ankle dorsiflexion

Weakness of ankle dorsiflexion (L4)
Weakness of ankle plantarflexion (S1)
Weakness of great toe extension (L5)
Weakness of hip flexion (L3)

"

Answer 80

B

Has been debated but whatever

Answer 81

"

Irradiated bone allograft is weaker in bending and fatigue strength as compared to fresh frozen bone allograft

"

Answer 82

Work up needed to rule out non accidental trauma

Answer 83

"You need lift on contralateral side, others said may

Syme – more energy efficient than midfoot even though its more proximal, stable heel pad is key – need to anchor
Syme is a great amputation because it preserves a longer lever arm, making it more functional than a transtibial amp.
It also has a cartilage end cap therefore appositional growth is not an issue so it can be used in children. Heel pad migration is always an issue with these foot amps and according to the technique for Syme’s you need to suture the fat pad to the anterior tibia to prevent migration (this is the biggest issue with Syme and why some people prefer a Boyd)
You need a rigid socket

○ You MAY need a contralateral shoe lift but not USUALLY.

"

Answer 84

"b. Anterolateral

● a. Anteromedial – near ulnar n.

● b. Anterolateral – near radial n

● c. Prox anteromedial

● d. Prox anterolateral – safer than anterolateral

● JAAOS 2014 – Elbow arthroscopy

○ Anterolateral portal has smallest margin of safe distance from neurovascular structure (radial n)

○ Margin of safety increases as move more proximal (away from radial n.)

not to be confused with “Published reports document injury to all major peripheral nerves about the elbow. In one series of 473 elbow arthroscopies, the ulnar nerve was most commonly involved, followed by the superficial radial nerve, posterior interosseous nerve, anterior interosseous nerve, and medial antebrachial cutaneous nerve, respectively

"

Answer 85

"a) Dwyer

Negative coleman means the the heel doesn't correct with the block = fixed hindfoot varus --> need to ostetomize the calc

Jones --> EHL to MT neck and fuse IP joint
PL to PB to correct for plantar flexed first ray
Medial cuneiform --> to help recreate tripid after correcting (dorsiflexing)

Jones

"

Answer 86

"Mortality. JAAOS 2021.

Of note, PTA is v. important to predict failure in ORIF. >20 = cannulated screws fail"

Answer 87

Superior migration, rocking horse

Answer 88

a) AP, Lateral, Internal oblique

Answer 89

"this is a repeat variant (see below)

c) Release the popliteus from the lateral epicondyle
- Popliteus = flexion
- IT band = extension

Previous question

During total knee arthroplasty in a patient with fixed valgus deformity, which of the following should be performed?

Release the IT band if the knee is tight in flexion
Release the popliteus if the knee is tight in flexion
Complete LCL --> CORRECT
Posterior capsule

Ref: Favorito PJ, et al. Total Knee Arthroplasty in the Valgus Knee. JAAOS 2002.

Krackow et al. developed a kinematic analysis model of the commonly released lateral structures in a cadaveric model. After release of the LCL, popliteus, lateral gastrocnemius, and IT band, < 5° of correction could be achieved in full extension if the PCL was retained.

If the release of the four lateral structures was combined with PCL sacrifice, a 9° correction could be achieved.

Releasing the LCL first allowed for a more gradual correction, with about 4° obtained after initial LCL release and a gradual increase to about 9° with release of successive secondary structures.
Because the LCL is the primary stabilizer of the lateral side of the joint, release of the secondary stabilizers (iliotibial band, popliteal tendon, posterolateral capsule) before the LCL may result in insufficient correction.
Subsequent release of the LCL may then result in overcorrection and instability.

"

Answer 90

A

But all prognostic in SPORC
- Smaller = better
- Location = typical posterolateral MFC better
- Stability = duh
- Physis = yes yes yes

Answer 91

b) Removal all cancellous bone from proximal femur

Unless you work at the UAH

Answer 92

"d) Anatomic lateral wall reduction
"

Answer 93

c) malignant change occurs in the 5th decade of life

JAAOS 2021.
Most common age is 35

Answer 94

"

This was in the 2022 concensus document debate as recalled differently

B. Autograft doesn’t affect rerupture rate (Recalled as “there are differences in rerupture rates with autograft tissue origin” by UofC/A/McGill)

Things to know
1. Autografts have lower re rupture than allo. But can use allo in multilig, revision or old ppl.
2. BTB has lower rates of rerupture in young atheletes compared to hamstrings. But, risk of anterior knee pain, fracture, tendinitis. Don't use ppl who spend lots of time on their knees..
3. LET decreases hamstring re rupture in young, lax ppl with at least a grade 2
4. Hamstring should have a diameter of at least 8 mm (Quads)

Things Ontario taught us:

● Medial meniscus pathology with chronic ACL tear

● PF arthrosis with chronic ACL tear/revision

● Recurrent instability episodes can cause chondral damage

● Allograft is a shit idea and leads to more rupture (trust me…)

● According to two recent metastatic reviews, there is no difference in retear rates between graft types, making A the correct answer.

"

Answer 95

"a.  Aorta blocks visualization of high to mid-T-spine on left. TRUE
b.  liver blocks visualization of lower T-spine on right. TRUE.
c. Resect T11 rib head to access T11-12 disc space. FALSE. RESECT THE LOWER RIB HEAD.
d.  Resect a rib 1-2 levels above the area of interest during approach

In this picture, the T8/9 disc has the t9 rib

"

Answer 96

"Medial blocking screw in proximal fragment. Wrong

Blocking screws on concave side
Blocking screw push nail to correct location

"

Answer 97

"

3. Early return to work in surgical intervention vs non-operative management

Canadian trial - all AC joints, didn't try to classify them due to issues with poor inter-reliability

Operative versus Non-operative Treatment of Acute Dislocations of the Acromioclavicluar Joint: Results of a Multi-centre Randomized, Prospective Clinical Trial83 patients with acute, complete dislocations of the acromioclavicular (AC) joint were randomized to undergo operative repair with hook plate fixation or non-operative treatment.

While the operative group demonstrated better radiographic results, they had 14 complications (7 major, 7 minor), including two reoperations, as compared to only three complications in the non-operative group (2 major, 1 minor) without reoperation.

The results of this study indicate that the non-operative group achieved significantly better early outcomes scores; however, these differences were lost at the final follow-up. By the 2 year follow-up there were no significant differences in clinical outcome scores between the two groups.

Non operative group had better PROMs early on, less reoperations, returned to work faster but had worse xrays at follow up

"

Answer 98

"Repeat variation
Chronic PCL: Lateral and patellofemoral compartment contact pressure increase --> FALSE. MEDIAL and PATELLA OA
Anteromedial bundle bigger and stronger. ** typo? AL = Anteriolateral is A LOT bigger
MRI in chronic injuries less effective than in acute injuries. Yes. MRI bad for chronic.
PCL and PLC dial test positive at 30 and 90. Yes
"

Answer 99

"a) with regard to spine OO the nidus is found on the convexity of the curve in scoliosis. Found on the CONCAVE SIDE

However, b has evidence too. Understand that OO in the hand can be painless

Osteoid Osteoma and Osteoblastoma. JAAOS. November 2011, Vol 19, No 11
OO is a benign bone-forming skeletal neoplasms that are characterized by the formation of osteoid or mature bone directly by the tumor cells. The lesion is usually <1.5 cm in diameter and contains a discrete central area known as the nidus that is surrounded by dense sclerotic bone tissue.

Typically, local pain that is typically more frequent and severe at night and that is relieved with administration of nonsteroidal anti-inflammatory drugs (NSAIDs)
I
n most cases, the concavity of the scoliotic curve is ipsilateral to the lesion as a result of muscle spasm and pain. Limb-length discrepancy may be associated with pediatric osteoid osteoma. One possible explanation for limb overgrowth in children with osteoid osteoma may be the resulting inflammatory response and associated hyperemia, especially in patients with lesions located near the open growth plate.

Rosenthal et al performed CT- guided RF ablation on 263 patients with a mean age of 19 years. In total, 271 ablation procedures were performed: 249 for initial tumor treatment, 14 for recurrence after conventional surgery, and 8 for recurrence after prior RF ablation. All the procedures were technically successful, and two minor procedure-related complications were observed. "

Answer 100

"b) femoral nerve injury.

A prospective randomized study on intra- medullary (IM) femoral nail fixation indicated a significantly increased incidence of internal malrotation >10° in patients treated on a traction table compared with those treated with manual traction (29% versus 7%; P = 0.007)

The incidence of pudendal nerve palsy has been reported to range from 1.9% to 27.6% due to excessive and/or prolonged traction against the perineal post. Erectile dysfunction (ED) is commonly associated with pudendal nerve palsy.
Hemilithotomy positioning of the uninjured leg on a traction table has been associated with well leg compartment syndrome."

Answer 101

Unstable elbow OCD lesion treated with debridement and macrofracture does poorly

Answer 102

"Repeat.B

Evaluation and Management of Posterior Wall Acetabulum Fractures. JAAOS. November 1, 2021, Vol 29, No 21

Roof arc angles, calculated on radiographs to determine congruency and used in treatment of other acetabulum fracture patterns, cannot be used to assess posterior wall stability (also ABC)

CT imaging identifies the amount of posterior wall involvement and other factors such as impaction, presence and location of incarcerated fragments, and fracture morphology.

An early CT-based study evaluating posterior wall fracture morphology demonstrated fractures involving less than 20% of the wall to be stable and more than 40% to be unstable.

The dynamic fluoroscopic examination under anesthesia (EUA) is the benchmark in assessment of hip stability, and fractures deemed stable by EUA have good radiographic and functional outcomes.

"

Answer 103

"
B. Decreases long term incisional tensile strength --> FALSE

The Use of Closed Incision Negative-Pressure Wound Therapy in Orthopaedic Surgery. JAAOS. May 1, 2018, Vol 26, No 9

Immediate Effects
Protection of the incision from external contamination
Decreased lateral tension on the incision
Increased appositional strength
Normalized stress distribution

Increased skin perfusion
Intermediate Effects
Decreased edema
Decreased hematoma/seroma formation
Increased lymphatic involvement

Long-term Effects
Improved incision quality Mechanical strength
Gene expression

"

Answer 104

"D. High rate of growth disturbance and requires regular follow-up

Clinical reports of growth deformity after ACL reconstruction are unusual. Cases of mild leg length discrepancy have been reported (1,17). However, cases of clinically significant growth disturbances are rare. Valgus morecommon than LLD.

Growth disturbance can occur after ACL surgery in children, and includes tibial recurvatum due to tibial tubercle apophyseal arrest as well as limb-length discrepancy and/or angular deformity due to physeal arrest or overgrowth.

Reconstruction options may be broadly categorized as physeal sparing (extraphyseal and all-epiphyseal), partial transphyseal, and transphyseal

Continued stability events can result in progressive meniscal and cartilage damage, as well as arthritic changes, which in 1 study occurred in 61% of 18 knees.

Management and Complications of Anterior Cruciate Ligament Injuries in Skeletally Immature Patients: Survey of The Herodicus Society and The ACL Study Group. 2002, Volume 22 (4), p 452–457

Current Concepts Review Management of ACL Injuries in Children and Adolescents. THE JOURNAL OF BONE & JOINT SURGERY d JBJS.ORG VOLUME 99-A d NUMBER 7 d APRIL 5, 201

"

Answer 105

"D) Varus alignment of the knee and ankle

Manifestations of hereditary multiple exostoses. JAAOS. Mar-Apr 2005;13(2):110-20.

MHE

· Male predominance, autosomal dominant inheritance with mutation in ext1/2 genes with variable penetrance MHE is an autosomal-dominant disorder with greater than 95% penetrance

· Tend to be bilateral and symmetric

· One side may predominate

· High risk of malignant transformation - may be up to 10%

· Xray looks like an Erlenmeyer flask

Associated with

o short stature

o limb-length discrepancies

o valgus deformities of the knee and ankle

o asymmetry of the pectoral and pelvic girdles

o bowing of the radius with ulnar deviation of the wrist

o subluxation of the radiocapitellar joint. MADELUNGS LIKE DEFORMITY

"

Answer 106

"Effect of Surgery vs Functional Bracing on Functional Outcome Among Patients With Closed Displaced Humeral Shaft Fractures. The FISH Randomized Clinical Trial

Inclusion criteria
· Age: 18 years or older
· Unilateral displaced humeral shaft fracture
· Displacement was at least the amount of the thickness of the cortex or in transverse fractures diastasis of the half of the thickness of the cortex was required
· Fracture was lying in a zone delimited proximally by the superior border of the pectoralis major
· tendon attachment and distally by the line lying 5 cm from the upper border of the olecranon fossa as
· evaluated from the x-ray (see Figure 2 A in the main publication for illustration)
· The fracture was less than 10 days old
· The patient was willing to accept both treatment options and willing to participate in all follow-up visits

Reason for crossover to surgery
· Nonunion (time range, 3-7.5 mo)
· Loss of reduction (at 6 wk)
· Refracture (at 8 mo)
· Intolerable pain in the fracture site (at 1 wk)
· Not tolerating the bracing (at 1 and 6 wk)

Results revealed significantly favourable DASH scores, pain scores during activity, Constant-Murley scores, elbow range of motion, DASH work module scores, and patient satisfaction with shoulder function and upper limb function in the surgery group compared to the bracing group. However at 12 months post-operation, no significant differences in all outcomes were observed between the two groups, with exception of DASH sports module scores which were significantly in favour of the surgery group. At 12 months, a significantly higher proportion of patients in the surgery group were willing to repeat the same treatment compared to the bracing group.

Eleven patients (25%) allocated to functional bracing developed fracture nonunion. Three patients (8%) allocated to surgery developed a temporary radial nerve palsy.

"

Answer 107

"Thermal and chemical adjuvants are the most critical point for local control - FALSE

Giant Cell Tumor of Bone. JAAOS. February 2013, Vol 21, No 2

Intralesional curettage is the main-stay of management for primary GCT of bone but local re- currence rates approach 20% without local adjuvants

Blackley et al16 reported a 12% recurrence rate in GCT of bone following extended curettage with a high-speed burr only, no adjuvant treatment, and allograft packing.

Cryosurgery has been shown to reduce the local recurrence rate to <8%. Cryosurgery involves the direct application of liquid nitrogen into the tumor cavity as a freeze- thaw couplet that can be repeated to improve its efficacy.

Although cryotherapy has been shown to be an effective adjuvant, it is associated with an appreciable incidence of pathologic fracture and vascular injury.

“The physical act of tumor extirpation likely reduces local recurrence more than does the use of adjuvants”

"

Answer 108

"They have potential to metastasize. Repeat. Always

Lipomatous Soft-tissue Tumors. JAAOS. November 15, 2018, Vol 26, No 22

The terms ALT and well- differentiated liposarcoma (WDL) represent tumors with identical histology but differ in anatomic location and clinical outcomes

The World Health Organization now uses the term ALT for extremity-based or superficial trunk lesions and reserves the term WDL for masses arising from the retroperitoneum, the mediastinum, or paratesticular locationst

ALTs tend to be larger, have thicker fibrous septae (.2 mm), and can display enhancement on MRI post-contrast sequences
ALTs have an excellent prognosis, with essentially 100% survival.1 The reported local recurrence rates vary from 8.2% to 50.61%, with the largest series of 151 patients demonstrating a 10% risk.
The risk of malignant dedifferentiation ranges from zero to 5%.

"

Answer 109

"1 and 2 are wrong

Chiari, capsule turn to hyaline cartilage - it turns into fibrocartilage (this may be a typo).
Chiari: This medial-displacement osteotomy uses cancellous bone with the interposed capsule as the new articulating surface
It is postulated that the bone augmentation undergoes metaplasia becoming a fibrocartilaginous structure.

But Shelf also doesn't medialize the hip

The Salter osteotomy is an open wedge osteotomy which retroverts and extends the acetabulum around a fixed axis such that the acetabular roof covers the femoral head both superiorly and anteriorly

"

Answer 110

"Common with displaced dorsal DR more than undisplaced

https://www.wheelessonline.com/muscles-tendons/extensor-pollicis-longus-rupture/

· If dorsal radial tubercle has been disrupted by Colles frx (producing irregularity), EPL tendon may rupture due to added friction imposed upon it as it turns around roughned tubercle
· Ruptures occur most often just distal to the extensor retinaculum (at Lister's tubercle)
· Rupture is far more common in assoc w/ undisplaced frx than in associated w/ displaced frxs, & it has been reported in patients who had wrist injury w/o a fracture
o Rupture of this tendon after minimally displaced frx suggests ischemic etiology rather than attritional rupture over an osseous spike
· Ruptures occur most often between 3 weeks and 3 months following injury

· Treatment:
o EIP (more ulnar) EPL
§ direct repair: often difficult due to tendon retraction and atrophy (or fraying) of tendon edges

"

Answer 111

"Debated

C) double limb support is less on the prosthetic side

"

Answer 112

"

d) The slope of the lateral plateau should be >10 degrees compared to the medial side

a) Lateral plateau is flat or convex – true, medial concave

b) Lateral plateau can be slightly wider (2mm) than the lateral femoral condyle – yes https://pubmed.ncbi.nlm.nih.gov/29700856/

c) The proximal tibia should be in approximately 3 degrees of varus – yes

d) The slope of the lateral plateau should be >10 degrees compared to the medial side – FALSE https://pubmed.ncbi.nlm.nih.gov/27587744/
The mean (±SD) medial TS was 6.9° ± 3.7° posterior, which was greater than the mean lateral TS of 4.7° ± 3.6° posterior ( P < .001)

"

Answer 113

"Low grade osteosarc and fibrous dysplasia are hard to tell apart on histo

Debated. Orthobullets has 25% pathological fracture rate (is this high). Also has FD and parosteal osteosarc similar on histo.

■ Dal tumor fellow: C 100% wrong, D surface lesion, NOT dense bone

https://journals.lww.com/pathologycasereviews/fulltext/2001/01000/low_grade_central_osteosarcoma_versus_fibrous.5.aspx- States similar path for low grade central osteosarcoma and fibrous dysplasia

● Low-grade central osteosarcoma is a rare subtype of osteosarcoma that was first described by Unni et al. in 1977. In contrast, fibrous dysplasia is not a true neoplasm, but rather a developmental abnormality. It represents one of the more commonly encountered benign lesions of bone. Despite these differences, the main feature that brings these two tumors together is their remarkably similar histologic appearance. In addition, there can be overlap in their radiographic features. This can cause diagnostic difficulties that may lead to misdiagnosis and inappropriate treatment. The problem is compounded by the fact that, because low-grade central osteosarcoma is so uncommon, most pathologists and radiologists rarely see it. Therefore, it is difficult to recognize. "

Answer 114

"

b. Back pain more common in non-bracing

2013 NEJM BRAIST trial (Effects of Bracing in Adolescents with Idiopathic Scoliosis)

A = TRUE, no difference in QoL scores.

■ The average PedsQL scores22 for patients included in the primary and intention-to-treat analyses did not differ significantly between the bracing and observation groups at baseline (Table 1 and Table 3) or at the final follow-up assessment

B = FALSE, no differences in back pain between groups

■ There were no significant differences between the bracing and observation groups in the primary analysis with respect to the percentage of patients with any adverse event (P=0.32) or the percentage of patients reporting back pain, the most common adverse event (P=0.29)

C = TRUE, longer than 12 hrs more effective. DOSE DEPENDENT.

■ The lowest quartile of wear (mean hours per day, 0 to 6.0) was associated with a success rate (41%) similar to that in the observation group in the primary analysis (48%), whereas brace wear for an average of at least 12.9 hours per day was associated with success rates of 90 to 93%

D = TRUE, lowers risk for surgery

■ In conclusion, bracing significantly decreased the progression of high-risk curves to the threshold for surgery in patients with adolescent idiopathic scoliosis. We brace curves 25 - 40 degrees.

"

Answer 115

d. Most patients should get radiation after surgery

Answer 116

"a. Intra-abdominal injury

■ Contraindications (wheeless)

● unacceptable shortening or angulation;

● open fractures;

● thoracic or intra-abdominal trauma;

● large or obese children (inability for parents to care for child)

"

Answer 117

"

You cannot measure the alpha angle on this view - FALSE

Long debate, seems like the above is the best to choose

○

"

Answer 118

" En bloc resection and selective embolization

Most common posterior element tumours are:

■ Osteoid Osteoma – responds to NSAIDS

■ Osteochondroma

■ Osteoblastoma

■ ABC - fluid fluid on CT and MRI

JAAOS 2016 - Evaluation of Back Pain in Children

Up to 20% of aneurysmal bone cysts are located in the spine.³¹ Most of these lesions involve the posterior elements; however, they can extend into the anterior vertebral body and can sometimes span two to three adjacent vertebrae.

MRI shows multiloculated, expansile lesions with fluid-fluid levels and a low-intensity signal on T1-weighted images and a high-intensity signal on T2-weighted images (Figure 6).

Because of the aggressive nature of aneurysmal bone cysts, surgical intralesional curettage and bone grafting are indicated. Biopsy with intraoperative histologic examination of frozen sections should be done before the curettage of a cyst.³⁰

Selective arterial embolization may be used preoperatively to minimize intraoperative bleeding

"

Answer 119

"

Answer: B. Long debate, this is what we are going with as group nation wide

JAAOS 2019 - Orthopedic Manifestations of Sickle Cell Disease

Sickle cell and OM have periosteal reaction

The differentiation of bone infarction from acute osteomyelitis in patients with SCD can be challenging. Often, the clinical presentation of these conditions is similar.

Plain radiographs obtained during the early phases of either condition often have normal findings or show only soft-tissue swelling. At 2 weeks, both conditions may show periosteal reaction and radiographs are of limited utility in differentiating the two conditions.

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Answer 120

"Debated, depending if you look at the new or old JAAOS.

We all wnt with C. Don't look at new JAAOS.

Concerns for fetal malformation are greatest during weeks 3 through 15 of gestation, when the fetal CNS is developing. After week 15, the fetal CNS is less sensitive to radiation at appropriate imaging dose

3rd-5th weeks are bad, so is 6-13th – beyond 14th is slightly better

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Answer 121

a. Olecranon

Answer 122

"c. CT

● Orthobullets

Hook of hamate fractures are rare, often missed, injuries generally as a result of a direct blow to the hamate bone most commonly seen in athletes.
Diagnosis is confirmed with either a radiographic carpal tunnel view or CT scan
Risk factors - often seen in athletes in sports requiring gripping: golf, baseball hockey

○ Radiographs

■ recommended views

○ PA and lateral of wrist

■ 10% sensitivity

○ carpal tunnel view

■ best radiograph to see hook of hamate fracture

■ 40% sensitivity

○ CT

■ indications

● establish diagnosis if radiographs are negative

■ findings

● may see sclerotic fx line in chronic injuries

■ 92% sensitivity

● can be missed if nondisplaced and if CT cuts greater than 1 mm

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Answer 123

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c. Young age

● Shadgan B, Pereira G, Menon M, Jafari S, Darlene Reid W, O’Brien PJ. Risk factors for acute compartment syndrome of the leg associated with tibial diaphyseal fractures in adults. J Orthop Traumatol. 2015;16(3):185-192.

○ CANADIAN CONTENT

○ This is one of the largest studies examining the possible risk factors that influence the occurrence of ACS in tibial diaphyseal fractures treated by surgical fixation

○ We found that younger patients are definitely at a significantly higher risk of ACS

■ Gender, mechanism of injury, Gustillo and anatomical classification, ISS and intramedullary nailing of tibial fracture did not influence ACS

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Answer 124

"a. Length of time of exposure to chlorhexidine is accumulative

adhesive drapes are bad. Dont' tell Bouliane

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Answer 125

b. Midfoot is common

Answer 126

a. Cemented pegged all-poly

Answer 127

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a. Anterior column and wall

b. Posterior column and wall

c. Anterior column and posterior wall

d. Posterior column and anterior wall

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Answer 128

c. Stiffness

Answer 129

a. Limb alignment

Answer 130

b. Periprosthetic fracture

Answer 131

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d. C6 superior endplate fracture

""Endplate fractures of the inferior level in jumped facets appears to be a major risk factor of biomechanical failure. However, a facet fracture may not be a risk factor for failure. In the absence of an endplate fracture, ACDF is a reasonable treatment option in patients with single-level cervical facet dislocation.""

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Answer 132

a. Alpha defensin is poor in the setting of metallosis - True

b. Need to do a manual cell count in metallosis - TRUE.

c. CRP and ESR will be abnormal in the setting of low grade/indolent infection - FALSE

d. New genetic analysis holds promise in diagnosing culture negative PJI TRUE

Answer 133

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A. Nickel common

JAAOS Metal Hypersensitivity in TKA 2016

Most sensitive metals - nickel > cobalt > chromium

10-15% in general population
Generally Type 4 allergic reaction

Delayed cell mediated with T lymphocytes

Clinical Syndrome

Dermatitis

Eczema, usually on the knee but ca include whole body

JAAOS Allergic or Hypersensitivity Reactions in Ortho Implants 2017

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Answer 134

"BDI > 12mm. Repeat variation

JAAOS 2014 - Upper Cervical Spine Trauma

Increased BDI and BAI (Harris Rule of 12s)

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Answer 135

b. Varus 35 degrees angulated

<3 cm short, < 30 varus / valgus, < 20 AP

Answer 136

Consult urology to repair while you fix the pelvis

intrapelvic rupture

Answer 137

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a. Physiologic

b. Achondroplasia - growth plates normal

c. Blount’s - no femur

d. Rickets - wide growth plates

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Answer 138

. Pudendal

Answer 139

Links PIP and DIP motion

Answer 140

Skeletal survey

MRI will be useless unless sedated

Answer 141

"a. But lets cover some things

When is the highest pressure?
1. When you insert the guide wire

2. Does venting work?

Well yes but still pressure above what embolize

3. What do we do in canada?

•Of the 223 Ontario Orthopedic Surgeons
-32% said that they always or sometimes vented

Ø67% said that they had never vented

4. Does RIA work

yes, but clinical utility meh

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Answer 142

"More HO with 2 incision - true
More LABCN with single incision - true
Both can have PIN injury - true

One incision 10% more supination strength -- see UBC paper

JAAOS 2018

LABCN is most commonly injured nerve

LABCN is the terminal sensory branch of the musculocutaneous n.

Bone tunnel and cortical button have lower complication rate than suture anchor and interference screw.
No difference in complication rate between single and double incision: 24% single and 26% double (p=0.3).
Comparison:

Single incision higher risk LABCN injury
Double incision higher risk of synostosis and HO

Separate point: Double incision gives more flexion strength (HULC paper 2012), single incision more supination strength (2019 UBC paper stockton et al)
Contrary to our hypothesis, we found a 20% mean improvement in terminal supination torque for acute distal biceps ruptures repaired with the SI technique compared with the DI technique. This finding may have clinical significance for the more discerning, high-demand patient.

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Answer 143

Resists shear at apex in partial articular

antiglide -->Refers to diaphyseal butress vs metaphyseal (butress)

Answer 144

d. Mechanical axis deviation < 40mm

a. BMI >45 - too fat

b. Age > 14 - too old

c. Metaphyseal diaphyseal angle > 35 - too sever

Answer 145

a. 2 mm of radius shortening - prob be fine

b. 1 mm intra-articular step deformity - thats all distal radius, they are fine

c. 5 degrees of dorsal tilt

d. Less than 10 degrees of radial inclination on PA XR - thats way off