2021

Question 1

Which of the following procedures generate aerosols from most to least:

a. Traction pin, high speed burr, knee aspiration
b. Removal of hemovac, rongeur of bone, electrocautery
c. Pulse lavage, suction, dressing care
d. Joint aspiration, osteotome, reaming for nail

Answer 1

C

Question 2

Which of the following measurements is worrisome for atlanto-occipital instability (repeat):

a. Basion dens interval >12 mm
b. Basion axis interval <12mm
c. SAC<13mm
d. PADI<15mm

Answer 2

A

Harris Rule of 12: basion-dens interval >12 mm suggests occipitocervical dissociation

Question 3

Simple elbow dislocation, gets reduced. Post reduction it is stable in extension but opens up with valgus stress. What is the best treatment option:

a. Open repair of LUCL
b. Application of Ex-Fix
c. Splint in 90 degrees of flexion in supination for 3-4 weeks
d. Splint in 90 degrees of flexion in supination for 1-2 weeks

Answer 3

D

Black Book & orthobullets – splint at 90 deg for 5-10 days, early therapy

Question 4

Most common cause for early failure in a mobile bearing medial UKA?

a. Progression of arthritis to tricompartmental arthritis
b. Infection
c. Loosening of implants
d. Bearing dislocation

Answer 4

C

Medial UKA:
Early failures (ie, <5 years) were most commonly caused by aseptic loosening (25%), progression of OA (20%), bearing dislocation (17%), pain (8%), infection (7%), and tibial subsidence (7%).

Lateral UKA:
Most common failure modes in lateral UKA were progression of osteoarthritis (OA; 29%), aseptic loosening (23%), and bearing dislocation (10%)

Question 5

Incomplete spinal cord syndromes. Best to worst prognosis?

a. Brown-Sequard - Central Cord - Anterior Cord
b. Anterior Cord - Central Cord - Brown-Sequard
c. Central Cord - Brown-Sequard - Anterior Cord
d. Brown Sequard - Anterior Cord - Central Cord

Answer 5

A

Orthobullets:
Brown Sequard: Excellent, 99% ambulatory, best prognosis for functional motor activity
Anterior: worst of incomplete SCI, most likely to mimic complete cord, 10-20% chance motor recovery
Central: good though full functional recovery rare. Usually ambulatory, usually have bladder control, often permanent clumsy hands
-lower ext, bowel & bladder, proximal upper, then hands last to recover

Question 6

5 year old girl presents with toe walking. What is the most concerning finding on her exam?

a. Unilateral
b. Going on for 3 years
c. No DF past neutral
d. Unchanged with age

Answer 6

A

JAAOS 2012
ITW is best described as bilateral persistent toe walking with or without a fixed equinus contracture without other discernible etiologic abnormalities in patients aged greater than
Toe walking before 2 is considered normal, and a normal progression of gait
Beware 5 year old who has recently begun to toe walk, especially unilateral
Idiopathic toe walking is a term used to define a gait in which a person walks with a toe‐toe gait pattern without any known correlated etiology
It is very important to make this a dx of exclusion as this can be due CP, Duchannes, tethered cord, diastematomyelia, Autism, schizophrenia, global developmetal delay, CMT, spina bifida etc
May have AD inheritance!

Question 7

Pseudosubluxation of the C-spine. What is true?

a. Can differentiate from true subluxation by measuring a line through the tip of the spinous process
b. Most common at C3/4
c. Due to vertical facets
d. Can be associated with posterior step of the bodies

Answer 7

D

Swischuk line - NOT THE SPINOUS PROCESS, but the anterior aspect of the posterior arch
>1.5 mm is abnormal
Happens due to horizontal facets
C2/3 most common
pseudosubluxation corrects with hyperextension

Question 8

Elderly patient comes to you with thumb weakness and trouble grasping. He has MCP hyperextension with flexion of the interphalngeal joint of the ring and pinkie finger. Which tendon transfer is best?

a. FCU to collaterals
b. Palmaris longus to extensor pollicis brevis
c. Palmaris longus to APB
d. FDS of long finger to adductor pollicis

Answer 8

D

Think it is describing low ulnar palsy with a positive froments sign. Therefore, tendon transfers
■ FCU to collaterals
■ Palmaris longus to extensor pollicis brevis
■ Palmaris longus to APB
■ FDS of long finger to adductor pollicis

Question 9

Osteosarcoma subtypes. What is true?

a. Periosteal is continuous with medullary canal
b. Periosteal will show up as a well defined osseous lesion with surface changes
c. Low grade osteosarcoma is hard to differentiate between fibrous dysplasia
d. Telangiectatic is associated with pathologic fractures

Answer 9

C

2024F consensus

Note path fracture with telangectatic osteosarc is ~25%

Question 10

6 week old who has U/S showing an alpha angle of 50 degrees and a beta angle of 55 degrees. You treat it in a pavlik, if you over tighten the posterior strap, what complication could you get?

a. Femoral nerve palsy
b. Pavlik disease
c. Posterior subluxation
d. AVN

Answer 10

D

Question 11

Older guy with previous back surgery L3-S1, now has back pain with PI=50, LL=25, SVA= 10 cm forward. What treatment is the LEAST INVASIVE AND COMPLICATED?

a. Smith-Peterson Osteotomy L2-L5
b. PSO at L3
c. Laminectomy L3-S1
d. Vertebral body resection at T10

Answer 11

B

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

PSO - 30 degrees per level (or about 9 cm sagittal balance correction)
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

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

Question 12

11 year old boy with back pain. CT and MRI shown. What treatment is associated with the lowest risk of recurrence? (?ABC of spine)

a. Curettage and selective embo
b. En-bloc resection and selective embo
c. Cryotherapy
d. Radiofrequency ablation

Answer 12

B

Most common posterior element tumors are:
Osteoid Osteoma – responds to NSAIDS
Osteochondroma
Osteoblastoma
ABC - fluid fluid on CT and MRI

Re ABC in peds:
– Marginal resection and en bloc excision have the lowest recurrence rates when feasible
-standard treatment is still intralesional curettage with adjuct

Question 13

11 year old girl with proximal femoral lytic lesion with cortical erosions, lytic lesions in the diaphysis as well. No pain with ROM, systemic symptoms or soft tissue mass. Has insidious onset of thigh pain.

a. Fibrous dysplasia
b. Langerhans cell histiocytosis
c. Osteosarcoma
d. Bone cyst

Answer 13

A

-Concensus answer was FD:
Proximal femur most common
central lytic lesions in medullary canal (diaphysis or metaphysis)
may have cortical thinning with expansile lesion
highly lytic lesions or a ground glass appearance
“punched-out” lesion with well-defined margin of sclerotic bone is common
modest expansion of bone
Shepherd’s crook deformity

EG is more often diaphyseal:
eosinophilic granuloma
commonly presents in the skull, ribs, clavicle, scapula, mandible
isolated lesions of the spine (thoracic most common)
can also occur in diaphyseal regions of long bones and the pelvis

Question 14

28 year old female is in an MVC. Polytrauma case, has a pneumothorax and gets chest tube placed. Other injuries included subarachnoid hemorrhage, liver laceration (managed conservatively). Binder on, traction applied. Right sided comminuted pilon, pelvic ring, and right femoral shaft fracture. On presentation, pH 7.13, lactate 4.8. Is resuscitated with 4u pRBC. Lactate goes down to 3.1, pH 7.29, HR 110, BP 110/80, RR 20.

a. DCO of all with early care > 48 hours
b. Early acute care of pelvis and femur (within 36 hours) with ex fix of pilon
c. Early care all within 36 hours
d. Pelvic angio and DCO of all fractures

Answer 14

B

Question 15

What is the most common association in Klippel-Feil?

a. Scoliosis
b. Renal anomaly
c. Deafness
d. Synkinesis

Answer 15

A

Orthobullets Klippel Feil:

Associated conditions:
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

Question 16

T10 burst fracture with incomplete canal stenosis. Altered (but present) sensation groin to sacrum, no voluntary anal contraction. ⅖ hip flexion, ⅗ knee flexion, ankle dorsiflexion, toe extension. What is their ASIA grade (AIS)?

a. A
b. B
c. C
d. D

Answer 16

D

Question 17

Reamed tibial nail non union is 5% and in un-reamed tibialm nail nonunion is 10%, what is the NNT?

a. Inverse of relative risk
b. 5
c. 10
d. 20

Answer 17

D

Question worded You are comparing reamed and unreamed tibial nails in a study, you find the nonunion rate to be 5% for reamed compared to 10% for unreamed. What is the number needed to treat? On previous test
For this case ARR = 0.1 - 0.05 = 0.05
NNT = 1/ ARR = 1/0.05 = 20

Question 18

You are the principal investigator of an RCT. There is an increased female to male ratio in one group with a significant difference. However, every other demographic parameter is equal. What is the most appropriate next step?

a. Reopen the study and recruit to a predetermined number
b. Reopen the study and recruit until they even our
c. Perform the analysis as it is due to chance
d. Remove from the female group to even them out

Answer 18

C

No explanation in doc

Question 19

What is the mechanism of action of Botulinum toxin (Botox) (repeat)

a. Inhibition of acetylcholine release from the presynaptic terminal
b. Inhibition of acetylcholine binding post-synaptic
c. Inhibition of calcium release from sarcoplasmic reticulum
d. GABA agonist

Answer 19

A

B - succinylcholine
C - Dantrolen
D - Baclofen

Question 20

Secondary chondrosarcoma

a. Typically are high grade
b. Increased local recurrence in pelvis
c. Increased in Olliers as compared to multiple exostosis
d. Cartilage cap of osteochondroma will not change once skeletally mature

Answer 20

B

JAAOS - 2010 - Secondary osteosarcomas
Typically low grade
Recurrence rate of 10-20% after wide marginal excision, particular risk of recurrence in pelvis
Majority with singular osteochondroma and multiple exostosis, fraction arise from ollier’s and maffucci
Nothing about this

Question 21

Type 2 bado Monteggia (posterior subluxation). Treatment?

a. Reduce and cast in supination and flexion to 90
b. Reduce and cast in pronation and flexion to 90
c. OR
d. Reduce and cast in full extension and in pronation

Answer 21

D

2024F consensus

Question 22

50 year old man has a unilateral facet fracture/dislocation at C5/6 that has a closed reduction with a halo. What treatment has the best long term outcomes?

a. Collar 12 weeks
b. Halo 12 weeks
c. Posterior C5/6 lateral mass fusion
d. Anterior C5/6 fusion

Answer 22

D

Question 23

Phalangeal fractures, what is the most common complication of non-operative treatment?

a. Malunion
b. Non-union
c. Stiffness
d. Arthritis

Answer 23

C

Hardy MA. Principles of metacarpal and phalangeal fracture management: a review of rehabilitation concepts. Journal of Orthopaedic & Sports Physical Therapy. 2004 Dec;34(12):781-99.

It is well recognizedthat soft tissue scarring affects hand function more than fracturehealing, and joint stiffness is the most frequent complication offractures.

Question 24

AP Pelvis - what is true

a. Crossover indicative of anteversion
b. Sacrococcygeal joint is 1-3cm above the symphysis
c. Can’t measure alpha angle on an AP
d. Tonnis >15 = profunda

Answer 24

B

A.False - crossover sign is indicative of retroversion
C. Alpha angle - Ottawa paper
Alpha angle can be measured on the AP radiograph - however it may miss some CAM deformities as it is not always at the anterosuperior femoral head neck junction
D. Tonnis angle measures roof arc angle for hip dysplasia - not a measurement of coxa profunda

Question 25

All are true about LET, EXCEPT:

a. Increased lateral compartment pressure
b. Lower rates of graft rupture
c. Lower rates of clinical failure
d. Lower patient scores at 3 months post op

Answer 25

A

STABILITY study (CANADIAN)
-Statistically significant increase in P4 pain scale scores at 3 months for ACLR+LET over ACLR; difference resolved at 12 and 24 months
-Statistically significant difference in LEFS (lower extremity function scale; self-reported functional outcome) with ACLR functioning better than ACLR+LET at 3 months and 6 months; leveled out by 12 months
-At two years, 11% in ACLR group had reruptured compared to 4.5% in ACLR+LET; RR=-0.41, p<0.001
-They call primary outcome as graft failure defined as either need for revision ACLR or symptomatic instability associated with positive asymmetric pivot shift
-41% suffered primary outcome in ACLR compared to 25% ACLR+LET; RR=0.61, p<0.0001
-Remember, worse early outcomes with LET as it is a bigger surgery!

Question 26

You hear a crack as you move the arm during a TSA. All are risk factors, EXCEPT:

a. AVN
b. Post traumatic arthritis
c. Uncemented stem
d. Abnormal humeral version

Answer 26

D

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

Question 27

All of the following are true regarding the syndesmosis, EXCEPT:

a. AITFL resists ER primarily
b. PITFL resists IR primarily
c. To have IR instability, many structures need to be injured
d. The AITFL does not help with posterior translation

Answer 27

D

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

Question 28

Bracing and scoliosis, all EXCEPT?

a. Same pediatric quality of life scores (PedsQL) in patients with and without brace
b. Less back pain in the non brace group
c. Reduces the progression of high grade curves
d. Depose dependent effectiveness (>12 hours)

Answer 28

B

A = TRUE, no difference in QoL scores.
■ The average PedsQL scores for patients included in the primary and intention-to-treat analyses did not differ significantly between the bracing and observation groups at baseline 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, 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 who are at high risk for progressing (ie peak growth).

D = 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%

Curves over 45 - 50 progress 1 - 2 degrees one mature (bad study, but safe to say). So if you can get them to maturity with a curve < 40, you win. Remember, bracing goal is to prevent progression - ie finish with the same brace you came in with.

Question 29

All are true about TB of the spine, EXCEPT:

a. Faster progression of kyphosis in children
b. Has para- and prevertebral abscess
c. Causes most progressive kyphotic deformity in the lumbar spine
d. Usually involves the vertebral body

Answer 29

C

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.

Question 30

All are true about botox, EXCEPT:

a. No difference between botox and casting in dynamic contracture
b. No difference between botox and botox plus serial casting for increasing ROM
c. Sustained multilevel botox decreases the need and lowers the amount of ortho related procedures
d. Botox improves gait

Answer 30

B

2024F consensus
-Botox followed by casting is WORSE than botox alone
-botox mostly helpful in dynamic contractures

Question 31

What is the rate of syndesmosis malreduction found on CT post ankle ORIF

a. 5%
b. 10%
c. 20%
d. 50%

Answer 31

D

Gardner MJ, Demetrakopoulos D, Briggs SM, Helfet DL, Lorich DG. Malreduction of the tibiofibular syndesmosis in ankle fractures. Foot Ankle Int. 2006 Oct;27(10):788-92. doi: 10.1177/107110070602701005. PMID: 17054878.

13 patients (52%) had incongruity of the fibula within the incisura on CT scan (average 3.6 mm, range 2.0 to 8.0 mm), only four of whom had one or more abnormal radiographic measurements.

Question 32

Most common cause of Iatrogenic Hallux Varus

a. Modified Mcbride procedure
b. Release of lateral sesamoid sling
c. Resecting medial to 2mm lateral of sulcus of the 1st MT head
d. 1st TMT fusion with correction of IMA to 3deg

Answer 32

C

2024 consensus doc says C, but we haven’t seen this combination of answers before or after. I believe C is a very convoluted way of saying resecting the lateral sesamoids and lateral sesmoid sulcus (because they live in the lateral sulcus, so if you resect medial to that, you’re removing them)

Original McBride procedure removed the lateral sesamoid, but the modified leaves it to reduce hallux varus

Question 33

Out of the following, which primary spine bone tumor in pediatrics is most common?

a. Osteosarcoma
b. Osteoblastoma
c. Chondrosarcoma
d. Ewing’s Sarcoma

Answer 33

B

Question 34

Acceptable metacarpal neck parameters

a. 5 deg malrotation
b. 10mm shortening
c. 20deg angulation of the long metacarpal
d. 40deg angulation of the small metacarpal

Answer 34

D

Question 35

What is true of shoulder examinations for subscap tear– belly press, bear hug, lift off?

a. High sensitivity
b. High sensitivity, high specificity
c. Low sensitivity, low specificity
d. High specificity

Answer 35

D

Kappe T, Sgroi M, Reichel H, Daexle M. Diagnostic performance of clinical tests for subscapularis tendon tears. Knee Surg Sports Traumatol Arthrosc. 2018 Jan;26(1):176-181. doi: 10.1007/s00167-017-4617-4. Epub 2017 Jul 4. PMID: 28676889.

The most important finding of the present study was that despite being highly specific, the sensitivity of clinical tests for SSC tendon tears is limited, with the Bear Hug Test displaying the best sensitivity, especially for lesions to the upper SSC border

There were 32 SSC lesions accounting for an incidence of 30.2%. The sensitivity for all tests was 0.66, while the specificity was 0.82.

Question 36

What structure is most at risk with ventral penetrates of a C1 lateral mass screw?

a. Vertebral artery
b. Internal carotid
c. Anterior spinal cord
d. Occipital nerve

Answer 36

B

Vertebral artery - lateral penetration
Internal carotid artery - ventral penetration
Spinal cord - medial penetration

Question 37

With the hip flexed and knee extended, what is the least injury to present with a tendinous avulsion?

a. Long head biceps tendon
b. Semitendinosus
c. Conjoint tendon
d. Semimembranosus

Answer 37

D

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.

Question 38

Isolated liner/head exchange for eccentric poly wear in setting lytic acetabular defect. What is the most likely complication?

a. Liner dissociation
b. Instability
c. Infection
d. Acetabular implant loosening

Answer 38

B

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.

Question 39

8 months old female with history of difficulty moving shoulder. Afebrile, normal CRP, ESR 25, WBC normal. No history of trauma reported.

a. Obstetrical brachial plexus palsy commonly presents at this age
b. Biopsy is indicated
c. Injury is suspicious for non-accidental trauma
d. IV antibiotics are indicated

Answer 39

C

Question 40

What is the most important role of the oblique retinacular ligament?

a. Prevents lateral bands from subluxating volarly
b. Prevents lateral bands from subluxating dorsally
c. Coordinates PIP and DIP motion
d. Coordinates MCP flexion

Answer 40

C

Wheeless:
- Oblique Retinacular Ligament:
- cord that runs from flexor tendon sheath at the proximal phalanx to the terminal extensor tendon;
- anatomy - oblique retinacular ligament
- origin - volar lateral crest of proximal phalanx;
- course - volar to axis of PIP joint
- insertion - lateral terminal extensor tendon;
- function:
- functional importance questioned;
- links motion of DIP and PIP joints;
- when PIP joint is flexed, ligament relaxes allowing DIP flexion;
- PIP extension tightens ligament facilitating DIP extension, thus theoretically linking motion of PIP and DIP joints;

Question 41

Which of the following are associated with a Gastrocsoleus contracture?

a. Hallux rigidus, neuropathic forefoot ulcer, charcot midfoot collapse
b. Morton’s neuroma, hallux rigidus, plantar fasciitis
c. Neuropathic forefoot ulcer, charcot midfoot collapse, plantar fasciitis
d. Plantar fasciitis, hallux rigidus, charcot midfoot collapse

Answer 41

C

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”

Question 42

What is true about the insertion of supraspinatus?

a. Inserts on part of the lesser tuberosity and anterior ⅓ greater tuberosity
b. Inserts on the middle ⅓ of the greater tuberosity
c. Inserts on the anterior ½ of the greater tuberosity
d. Inserts on the entire greater tuberosity

Answer 42

A

2024F consensus

Question 43

Patient presents with a femoral shaft fracture and gets an external fixator placed. 1 week later gets converted to definitive fixation with IMN. What is true about delayed vs. immediate fixation of femoral shaft fractures?

a. Increased infection
b. Increased non-union
c. Increased ARDS
d. Equivalent infection and non-union

Answer 43

D

-Infection rate does increase if ex-fix left in place >28 days
-Reduced risk of ARDS and fat embolism sydnrome
(Orthobullets)

Question 44

What is true about discitis in the pediatric patient?

a. Most common in 6 year old
b. Can diagnose early on XR
c. More common thoracic versus lumbar
d. >80% of cultures in biopsy will be positive for bacterial infection

Answer 44

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.
?Maybe early manifestations at 1 week

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

Question 45

Regarding the tribology of bearing surfaces in arthroplasty, which of the following is true?

a. In ceramic on ceramic boundary lubrication 28 mm heads
b. In ceramic on ceramic there is fluid-film lubrication all sizes
c. Metal on poly has fluid-film lubrication at all sizes
d. MoM has fluid-film lubrication with head size of 28mm

Answer 45

B

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.
C = 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 D = 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.
B = TRUE
therefore A = FALSE

Question 46

Which elbow arthroscopic portal is closest in location to a neuromuscular structure?

a. Anteromedial
b. Anterolateral
c. Proximal anterolateral
d. Proximal anteromedial

Answer 46

B

2024F consensus

We agreed that if the question asked what about purely sensory nerve most at risk we will say anteromedial portal (MABCN)

Question 47

What nerve is most commonly injured in hip arthroscopy?

a. Sciatic
b. Femoral
c. Superior gluteal
d. Pudendal

Answer 47

D

Kern, Michael J. MD; Murray, Ryan S. MD; Sherman, Thomas I. MD; Postma, William F. MD. Incidence of Nerve Injury After Hip Arthroscopy. Journal of the American Academy of Orthopaedic Surgeons: November 1, 2018 - Volume 26 - Issue 21 - p 773-778
doi: 10.5435/JAAOS-D-17-00230

Nerve injury was seen in 13 patients with an incidence of 13%. Specific nerves injured included the pudendal (9), lateral femoral cutaneous (2), sciatic (1), and superficial peroneal nerves (1). Subgroup analysis did not demonstrate a notable association between the risk of nerve injury and increased traction time, sex, or increased BMI. The technically demanding surgical skills was associated with a notable decrease in the traction time, but no notable difference in the risk of nerve injury was observed. Most nerve injuries resolved within 2 weeks (8 of 13), and all cases of nerve injury resolved within 9 months

Question 48

What muscle does the ulnar nerve innervate?

a. Flexor pollicis brevis
b. D2-5 lumbricals
c. D2-5 FDP
d. Pronator quadratus

Answer 48

A

The ulnar nerve innervates the flexor muscles of the forearm including the flexor carpi ulnaris and flexor digitorum profundus. It also innervates the intrinsic muscles of the hand including the palmaris brevis, lumbricals, hypothenar and interossei muscles. In the hand, superficial branch of the ulnar nerve innervates palmaris brevis muscle and sensory to the hypothenar muscles, fourth common digital nerve, and ulnar proper nerve. Deep branch innervates hypothenar muscles, opponens digiti minimi, interosseous muscles, third and fourth lumbricals, adductor pollicis and medial head of the flexor pollicis brevis.

Question 49

What is true regarding chronic exertional compartment syndrome?

a. Patient presentation is variable
b. Most common in deep posterior compartment
c. Low chance of recurrence with release
d. Associated with fascial hernias

Answer 49

D

Fraipont, Michael J. MD; Adamson, Gregory J. MD. Chronic Exertional Compartment Syndrome. Journal of the American Academy of Orthopaedic Surgeons: July 2003 - Volume 11 - Issue 4 - p 268-276

Of patients with CECS involving the legs, 39% to 46% have fascial defects over the anterolateral lower leg compared with asymptomatic individuals, who have <5% incidence.4,5 These fascial hernias or defects are usually 1 to 2 cm2 in size and occur near the intermuscular septum between the anterior and lateral compartments, often at the exit of the superficial peroneal nerve. The fascial hernia is approximately at the junction of the middle and distal thirds of the leg. The superficial peroneal nerve can be compressed by either the edge of the fascial defect itself or the muscle bulging through the defect. At rest, no palpable abnormality may be apparent, but with exercise, local tenderness and swelling may occur. Occasionally Tinel’s sign may be found at the site of the hernia.

Incidence
-second most common exercise induced leg syndrome
behind medial tibial stress syndrome

Demographics
-males >females
-often seen in 3rd decade of life
-runners or those who run a lot for their sport

Anatomic location
-anterior leg compartment most commonly affected (~70%)
-anterior and lateral leg compartment affected in 10%
-posterior leg compartment involvement associated with less predictable surgical outcomes

Recurrence
-up to 20% at a mean of 2 years after fasciotomy
because of fibrosis/scar formation
risk factors:
isolated compartment release

Question 50

A patient presents with pain and paresthesias over the left distal ulnar forearm and fifth finger. There are no motor deficits but sensory testing confirms sensory loss over the ulnar forearm and fifth finger. What is the likely cause? (REPEAT)

A. Left ulnar neuropathy at the wrist
B. Left cubital tunnel compression at the elbow
C. Left C7-T1 disc herniation
D. Left C6-C7 disc herniation

Answer 50

C

C8 root affected

Question 51

You are planning distal tibial allograft to correct an anterior glenoid bone deficiency from a failed Latarjet procedure. Which is true when comparing fresh frozen to irradiated allograft:

a. Irradiated bone allograft is weaker in bending and fatigue strength as compared to fresh frozen bone allograft
b. Bone allograft irradiation has no effect on BMP-7 or osteoblast differentiation
c. End product sterility of fresh frozen bone allograft is no different than irradiated
d. Bony allograft irradiation improves bone collagen crosslinking and impairs further strength

Answer 51

A

Although various reports have suggested minimal effect of radiation on Young’s modulus of allograft bone, irradiated bone has been shown to become “embrittled”, with a 64% reduction in energy to failure with 28 kGy29. In the same report, work to failure energy was reduced in a dose-dependent manner with escalating amounts of irradiation

Question 52

3 year old female with thigh pain and reduced knee ROM. No trauma. Shows an X-ray of a soft-tissue mass, with periosteal reaction in distal ⅓ femur. Which of the following is least likely to be on your differential diagnosis?

a. Leukemia
b. Osteomyelitis
c. Sickle cell
d. Subacute fracture

Answer 52

C
2024F consensus

Question 53

2 year old kid presents with bowing, what is your diagnosis? XR given. (showed definitively varus bowed femur and tibia, flared metaphysis of distal femur and proximal tibia. No looser zones, no champagne pelvis).

a. Achondroplasia
b. Rickets
c. Blounts
d. Physiologic

Answer 53

B

-Bilateral genu varum, particularly in obese children, may not always be due to rickets; Blount’s disease, fibular hemimelia, physiological bowing and skeletal dysplasias should also be considered in the differential diagnosis.
-Unlike rickets, cupping, fraying and splaying of metaphyses are absent in Blount’s disease. Rickets is associated with diffuse bowing throughout the bone rather than the characteristic proximal tibial deformity with medial beaking of Blount’s disease.
-A strong association exists between Blount’s disease and childhood obesity; with increasing prevalence of obesity, the prevalence of Blount’s disease also rises.
I-f untreated, it can lead to progressive deformities of the knees, distal femur and tibia, short stature and significant articular distortion resulting in premature osteoarthritis of the knees.

Looser zones, also known as cortical infractions, Milkman lines or pseudofractures, are wide, transverse lucencies with sclerotic borders traversing partway through a bone, usually perpendicular to the involved cortex, and are associated most frequently with osteomalacia and rickets. Looser zones contain regions of demineralized osteoid, frequently with superimposed osteitis fibrosa cystica due to the presence of hyperparathyroidism

Question 54

All are true about the PRIMARY goals of calcaneus fractures fixation except:

a. Anatomic reduction of the articular surface
b. Anatomic reduction of the lateral wall
c. Restore calcaneal length
d. Restore calcaneal width

Answer 54

B

Question 55

All of the following about osteochondromas are true except:

a. Proximal tibia lesions can be associated with arterial pseudoaneurysm
b. Pain can come from fracture at base
c. Prominent location can be associated with painful bursa formation
d. Malignant transformation more common after the fifth decade of life

Answer 55

D

Question 56

Regarding ACL reconstruction all are true except?

a. Chronic revision ACL associated with patellofemoral arthrosis
b. Autograft choice does not affects graft rupture
c. Recurrent instability can cause chondral damage
d. Medial meniscal tears with chronic ACL

Answer 56

B

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)
JM: <8mm has higher failure rates.
5. Chronic ACL = posteromedial OA + PF

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

Question 57

All are true about deformity in MHE, EXCEPT?

a. Short ulna and resulting radial bow
b. Short stature
c. Knee and ankle varus
d. Leg length deformity

Answer 57

C

Question 58

All are true about distal biceps EXCEPT?

a. LABCN rate higher in 1 vs 2 incision
b. Supination strength 10% more in single incision
c. PIN at risk in both single and double incision technique
d. More HO in 2 incision technique

Answer 58

B

Single incision increased supination 20%, not 10%.

Question 59

Sarmiento bracing for humeral shaft fractures is not as successful as initially reported. All are commonly cited reasons for conversion to ORIF EXCEPT?

a. Nonunion
b. Non-Compliance
c. Loss of reduction
d. Transverse fracture

Answer 59

D

Question 60

In adolescent genu varum, hemiepiphysiodesis is unlikely to be successful in all of the following scenarios, EXCEPT?

a. BMI > 45
b. Mechanical axis deviation by < 40mm
c. Age > 14
d. MDA>26

Answer 60

B

Question 61

Peds ACL question all are true except?

a. Options include physeal sparing, partial trans-physeal, and trans-physeal
b. Non-operative treatment is associated with increased chondral and medial meniscus injuries
c. Common to develop an angular deformity and should follow them long term
d. Allograft has an unacceptably high risk of rupture

Answer 61

C

Question 62

All are true about OCD lesions except?

a. Lateral femoral condyle lesion more likely to get surgery than the common posteromedial femoral condyle lesion
b. Arthroscopy and drilling for medial femoral condyle lesion heal well
c. Compared to elbow and knee OCD, talar OCD are diagnosed later due to longer asymptomatic period prior to diagnosis
d. Unstable elbow OCD lesion treated with debridement and microfracture does bad

Answer 62

D

Majority of unstable elbow OCD lesions treated with debridement and microfracture do well

1. TRUE - “t. OCD lesions at the lateral femoral condyle are more likely to progress to surgical treatment than those at the classic location on the medial femoral condyle” (1)
2. TRUE
3. TRUE - “Juvenile OCD lesions that are stable, yet fail non-operative treatments are indicated for arthroscopic drilling. This may either be done transarticular (transchondral) or by sparing the articular cartilage in a retroarticular fashion (extraarticular or intraepiphyseal). Retroarticular drilling is thought to be somewhat more technically challenging and does require the use of fluoroscopy (►Fig. 3). Kocher et al reported in 2001 a 100% rate of = radiographic healing in patients treated with arthroscopic transarticular drilling.19 In 2008, Donaldson and Wojtys reported that 92.3% of skeletally immature OCD lesions had excellent outcomes at an average of 8.5 months after surgery.48 In their study, an excellent result was noted by return to activity, normal physical examination findings, in addition to improvement in radiographic appearance of the lesion.48 Adachi et al found similar success with retroarticular drilling with 95% healing rates seen when evaluated with both plain radiographs and on MRI, as well as improved function based on Lysholm scores”

Question 63

In a type 3 AC joint injury all are true except?

a. CC and AC ligaments are gone
b. He will return back to work earlier with surgery
c. The clavicle is unstable in both the horizontal and vertical directions
d. The acromion is depressed as compared to the clavicle

Answer 63

B

Question 64

All are true about pediatric pelvis osteotomies except?

a. Salter retroverts the acetabulum
b. The hip capsule in a Chiari osteotomy transforms into hyaline cartilage
c. Pemberton provides improves global coverage
d. Shelf medializes the hip centre

Answer 64

B

Hip capsule in Chiari osteotomy turns into fibrocartilage

Question 65

What is false about EPL ruptures?

a. More common with dorsal displacement than with undisplaced fractures
b. EPL end to end repair unlikely to work
c. Most commonly presents at 3 weeks - 3months
d. Ruptures at Lister’s tubercle, just distal to the extensor retinaculum

Answer 65

A