OITE & AAOS Orthopedic Board Review MCQs: Part 87

About This Board Review Set

This is Part 87 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

This set has been strictly audited and contains 100 100% verified, high-yield multiple-choice questions (MCQs) modelled on the exact format of the Orthopaedic In-Training Examination (OITE) and the American Academy of Orthopaedic Surgeons (AAOS) board examinations.

How to Use the Interactive Quiz

Two distinct learning modes are available:

Study Mode — After selecting an answer, you immediately see whether you are correct or incorrect, together with a full clinical explanation and literature references.
Exam Mode — All feedback is hidden until you click Submit & See Results. A live timer tracks elapsed time. A percentage score and detailed breakdown are displayed upon submission.

Pro Tip: Use keyboard shortcuts A–E to select options, F to flag a question for review, and Enter to jump to the next unanswered question.

Topics Covered in Part 87

This module focuses heavily on: Arthroplasty, Elbow, Hip, Ligament, Nerve, Shoulder, Tumor.

Sample Questions from This Set

Sample Question 1: Thedirectanterior(Smith-Peterson)approachtohiparthroplastyismostcommonlyassociatedwithinjurytowhatnerve?...

Sample Question 2: Figures 71a and 71b/ are the MR images of a 65-year-old man who dislocated his shoulder.What is his most likely chief symptom?...

Sample Question 3: Figures below show the radiographs obtained from an 86-year-old-woman who has had chronic left hip pain for several years. She now uses a walker and a wheelchair for ambulation. She is medically healthy. What is the most appropriate surgica...

Sample Question 4: A professional pitcher reports pain localized to the medial aspect of his throwing elbow. History reveals that he was pitching in a playoff game and heard and felt a pop in his elbow. MRI reveals a complete ulnar-sided avulsion of the media...

Sample Question 5: A 16-year-old girl has had painless swelling in her posterior left arm for the past 4 months. A radiograph, MRI scans, and an incisional biopsy specimen are shown in Figures 43a through 43d. What is the cytogenetic translocation most common...

Why Active MCQ Practice Works

Evidence consistently demonstrates that active recall through spaced MCQ practice yields substantially greater long-term retention than passive reading alone (Roediger & Karpicke, 2006). All questions in this specific module have been algorithmically verified for clinical integrity and complete explanations.

Comprehensive 100-Question Exam

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Question 1

The direct anterior (Smith-Peterson) approach to hip arthroplasty is most commonly associated with injury to what nerve?

Explanation

DISCUSSION:
Some authors have reported the incidence of lateral femoral cutaneous nerve neuropraxia following hip arthroplasty with the direct anterior approach to be near 80%, but resolution of the sensory deficits has been observed in most patients over time. Femoral nerve palsy has been reported to occur in .64% to 2.3% direct lateral (Hardinge) and anterolateral (Watson-Jones) approaches, and the superior gluteal nerve may be injured with proximal extension of the abductor muscular dissection. The posterior approach has been reported to be associated with sciatic nerve injury, especially in cases of dysplasia. Pudendal nerve injury has not been reported with the anterior, anterolateral, direct lateral, or posterior approaches to hip
arthroplasty. It has been reported following hip arthroscopy and the use of a traction table, however.

Question 2

Figures 71a and 71b/ are the MR images of a 65-year-old man who dislocated his shoulder. What is his most likely chief symptom?

Explanation

CLINICAL SITUATION FOR QUESTIONS 72 THROUGH 75
Figures 72a through 72e are the MR images of a 12-year-old boy with left lateral-sided knee pain following a football injury. He has a several-year history of recurrent knee pain that improves with rest. An examination reveals a moderate effusion. Range of motion is 0 degrees
to 90 degrees and is limited by pain in deep flexion. He has tenderness to palpation along the lateral joint line, and no instability is noted.

Question 3

Figures below show the radiographs obtained from an 86-year-old-woman who has had chronic left hip pain for several years. She now uses a walker and a wheelchair for ambulation. She is medically healthy. What is the most appropriate surgical intervention?

Explanation

DISCUSSION:
This 86-year-old woman has poor bone quality and osteoarthritis of the left hip. Her lateral radiograph confirms Dorr type C bone quality. A hybrid left THA with a cemented femoral stem would be the treatment of choice.

Question 4

A professional pitcher reports pain localized to the medial aspect of his throwing elbow. History reveals that he was pitching in a playoff game and heard and felt a pop in his elbow. MRI reveals a complete ulnar-sided avulsion of the medial collateral ligament (MCL). Examination reveals valgus instability and ulnar nerve involvement. What recommendations should be made based on the patient’s desire to return to sport? Review Topic

Explanation

Injuries to the MCL usually result from repetitive high valgus stress on the medial aspect of the elbow joint due to overhead throwing or racquet sports. Excessive
stresses during the late cocking and acceleration phase of throwing can injure the anterior band of the MCL. Clinically, the injuries may present as chronic or acute, and a pop may be noted in the latter. Associated ulnar nerve involvement is common. Valgus instability is present in about 25% of patients. Patients typically are athletes who participate in throwing and have localized medial elbow pain and tenderness along the course of a ligament that extends from the medial epicondyle of the distal humerus to the sublime tubercle of the ulna. Surgical reconstruction is the procedure of choice in an athlete desiring a return to a high level of throwing.

Question 5

A 16-year-old girl has had painless swelling in her posterior left arm for the past 4 months. A radiograph, MRI scans, and an incisional biopsy specimen are shown in Figures 43a through 43d. What is the cytogenetic translocation most commonly associated with this tumor?

Explanation

DISCUSSION: This is a case of synovial sarcoma. The radiograph shows some soft-tissue swelling in the upper arm. The MRI scans show a lesion that has increased signal on T₂-weighted images and low signal on T₁-weighted images. There is a suggestion of a large cystic component to this lesion. The pathology shows a biphasic population of cells, a spindle cell component, and an epithelioid component. Up to 20% of synovial cell sarcomas have areas of cyst formation. The most common cytogenetic translocation with synovial cell sarcoma is X; 18. The 11; 22 translocation is most commonly associated with Ewing’s sarcomas; the 12; 22 translocation is most commonly associated with clear cell sarcomas; the 2; 13 translocation is most commonly associated with alveolar rhabdomyosarcomas, and the 12; 16 translocation is most commonly associated with myxoid liposarcomas.
REFERENCES: Kawai A, Woodruff J, Healey JH, et al: SYT-SSX gene fusion as a determinant of morphology and prognosis in synovial sarcoma. New Engl J Med 1998;338:153-160.
Sandberg AA: Cytogenetics and molecular genetics of bone and soft tissue tumors. Am J Med Genet 2002;115:189-193.

Question 6

What is the most likely explanation for the change between the initial intraoperative radiograph (Figure 11a) and the radiograph taken 4 weeks after surgery (Figure 11b) in an 87-year-old man who underwent primary hip replacement for osteoarthritis?

Explanation

DISCUSSION
The image demonstrates subsidence of the femoral implant. The implant subsided because it did not have good initial stability. The tapered femoral implant was placed after initial preparation for an anatomic femoral stem. A limited, nondisplaced femoral neck fracture was encountered during the procedure and treated. Two advantages of tapered stems are the efficient transfer of stress to the proximal femur and the ability to accommodate some subsidence to achieve enhanced stability. Although subsidence of a tapered stem to a more stable position can produce a good result, quality of metaphyseal bone should be considered. Attention to surgical technique remains important to optimize component stability for biological fixation.
RECOMMENDED READINGS
Savory CG, Hamilton WG, Engh CA Sr, Della Valle CJ, Rosenberg AG, Galante JO. 15 Hip designs. In: Barrack RL, Booth RE Jr, Lonner JH, McCarthy JC, Mont MA, Rubash HE, eds. Orthopaedic Knowledge Update: Hip and Knee Reconstruction 3.
Rosemont, IL: American Academy of Orthopaedic Surgeons; 2006:345-368.
Blaha JD, Borus TA. Press-fit femoral components. In: Callaghan J, Rosenberg A, and Rubash H, eds The Adult Hip. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2007:1036-1043.

Question 7

Which of the following has been shown to have similar biochemical and clinical characteristics as iliac crest autograft?

Explanation

DISCUSSION: In multiple studies, femoral intramedullary reaming debris has been shown to have similar biochemical characteristics as iliac crest autograft. Intramedullary reaming products have osteogenic potential with viable cells while BMP's are osteoinductive cytokines.
Hoegel et al found that the reamings had alkaline phospatase activity, indicating living osteoblasts. The amount of activity was independent of the reamer sizes and reamer design.
Frolke et al concluded that reaming debris supports callus building (healing) as much as conventional iliac crest bone grafting in an animal fracture gap model.

Question 8

A 17-year-old boy with left spastic hemiplegia secondary to cerebral palsy is being evaluated for persistent swan neck deformities of the affected hand. Splinting has been tried with some improvement, but the patient does not want to wear the splints any more. On physical examination, he demonstrates full extension of the metacarpophalangeal (MCP) joints, 30° of hyperextension of the proximal interphalangeal (PIP) joints, and flexion of the distal interphalangeal (DIP) joints when he attempts to actively extend his digits. He is able to initiate flexion at the PIP joints with his MCP joints held in neutral extension. He has equal PIP flexion when the MCP joints are extended and flexed. What is the most appropriate surgical treatment to address his swan neck deformity?

Explanation

EXPLANATION:
This patient demonstrates full extension of the MCP joints when he actively extends his fingers, indicative of overpull of the extrinsic finger extensors. This clinical scenario can be corrected by a central slip tenotomy. A terminal tendon release is used to address a Boutonnière deformity. The patient does not demonstrate intrinsic tightness (equal PIP flexion while the MCP flexed and extended), therefore his swan neck would be unlikely to respond to intrinsic lengthening. Dorsal rerouting of the lateral bands is performed for a Boutonnière deformity. A central slip tenotomy would balance the extension forces between the PIP and DIP joints.

Question 9

…A 56-year-old podiatrist with a negative past medical history had anterior knee pain after an injury. His radiographs, CT scan, and T1-weighted sagittal and fat-saturated axial MR images are shown in Figures 15a through 15e, respectively. After arthroscopic partial medial menisectomy, the patient was turned to the prone position and an open posterior arthrotomy and excision was performed. Low-power and high-power hematoxylin and eosin stained histologic specimens are shown in Figures 15f and 15g, respectively. Based on the history, radiographs, CT scan, MRI scans, and histologic findings, what is the most likely diagnosis?

Explanation

CLINICAL SITUATION FOR QUESTIONS 16 THROUGH 19
Figures 16a and 16b are the right femur radiographs of a 59-year-old man who has severe pain in his right distal thigh and knee with no significant trauma and an inability to bear weight. Blood tests demonstrate anemia, serum protein electrophoresis/urine protein electrophoresis findings are negative, and electrolyte levels are within defined limits.

Question 10

An 8-year-old boy falls and injures his thumb. A radiograph is shown in Figure 23. Initial management should consist of

Explanation

DISCUSSION: The radiograph shows a complete simple dislocation of the metacarpophalangeal joint. The clue to this injury is the perpendicular alignment of the proximal phalanx to the metacarpal on the lateral radiograph. This must be differentiated from the complete complex dislocation pattern that is irreducible because of the interposed volar plate. In lateral radiographs of these injuries, the long axes of the proximal phalanx and the metacarpal are parallel. Simple dislocations are amenable to closed reduction and casting. Some authors have recommended ulnar collateral ligament repair if instability is detected on examination after reduction.
REFERENCES: O’Brien ET: Part IV: Dislocations of hand and carpus, in Rockwood CA Jr, Wilkins KE, Beaty JH (eds): Fractures in Children, ed 4. Philadelphia, PA, Lippincott-Raven, 1996, vol 3, pp 429-431.
Bohart PC, Gelberman RH, Vardell RF, Solomon PB: Complex dislocations of the MCP joint. J Bone Joint Surg Am 1974;56:1459-1463.

Question 11

Compared with myodesis, osteomyoplasty offers which of the following advantages in transtibial amputation?

Explanation

Osteomyoplasty in transtibial amputation, originally described by Ertl in 1949, features creation of a bone bridge between the distal tibia and fibula, which is
theorized to enhance bony stability and increase end-bearing of the residual limb, and may enhance patient-perceived functional outcomes relative to myodesis. Fibular abduction is a known complication of traditional myodesis techniques, and is believed to represent syndesmotic instability. Osteomyoplasty requires additional surgical time and increased surgical morbidity, and because the success of the procedure is dependent on achieving bony union, early prosthetic fitting and immediate weight bearing are typically contraindicated.

Question 12

Which of the following radiographic findings indicates that the injury to the great toe shown in Figures 60a and 60b should be reducible by closed manipulation?

Explanation

In the case of first MP joint dislocation, though rare, there is a complete disruption of the intersesamoid ligament, at separation of the sesamoid seen or x-ray (Type II). This dislocation can be readily reduced. A Type I lesion/dislocation yields no disruption of the sesamoid mass though a dislocation is present. This type I lesion are usually irreducible if attempted closed.

Question 13

A 42-year-old woman is brought to the emergency department following a motor vehicle accident. She has sustained multiple injuries, and she is intubated and pharmacologically paralyzed. Sagittal cervical CT scans through the right cervical facets, the left cervical facets, and the midline are shown in Figures 12a through 12c, respectively. Definitive management of her cervical injury should consist of

Explanation

DISCUSSION: The CT scans reveal an occipital-cervical dissociation with subluxation of the occipitocervical joints bilaterally. Definitive management should consist of an occipital-cervical fusion with instrumentation. Immobilization in a Philadelphia collar is inadequate for this highly unstable injury, and halo immobilization, while affording adequate temporary immobilization, is not appropriate definitive management for this ligamentous injury. The patient does not have an injury at C4-C5 or C6-C7.
REFERENCES: Jackson RS, Banit DM, Rhyne AL III, et al: Upper cervical spine injuries.

J Am Acad Orthop Surg 2002;10:271-280.
Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 201-216.

Question 14

A 24-year-old woman who has hypotension, a head injury, and who experienced a poor response to resuscitation has been taken to the operating room for a splenectomy. Following abdominal surgery she remains unstable with increasing pulmonary respiratory pressures and decreasing oxygen saturation. She has a transverse mid-diaphyseal fracture of the tibia with a 4-cm laceration and soil-contaminated muscle in the wound. Based on these findings, management should consist of

Explanation

DISCUSSION: Because the patient is critically ill and requires expeditious care, stabilization of the long bone fracture is required, but definitive care of the fracture should be postponed. The treatment of choice at this time is irrigation with 12 L of saline solution, followed by debridement and nondefinitive stabilization with a simple four-pin external frame to regain axial and rotational alignment. When the patient’s condition is more stable, more definitive care can be performed.
REFERENCES: Bosse MJ, Kellam JF: Orthopaedic management decisions in the multiple trauma patient, in Browner BD, Jupiter JP, Levine AM, Trafton P (eds): Skeletal Trauma, ed 2. Philadelphia, PA, WB Saunders, 1998, pp 151-164.
Weresh MJ, Stover MD, Bosse MJ, Jeray K, Kellam JF: Pulmonary gas exchange during intramedullary fixation of femoral shaft fractures. J Trauma 1999;46:863-868.
Scalea TM, Boswell SA, Scott JD, Mitchell KA, Kramer ME, Pollak AN: External fixation as a bridge to intramedullary nailing for patients with multiple injuries and with femur fractures: Damage control orthopedics. J Trauma 2000;48:613-623.

Question 15

What is the most common causative bacteria in septic arthritis in children? Review Topic

Explanation

The spectrum of causative bacteria and frequency of occurrence of specific pathogens in septic arthritis are similar to those seen in osteomyelitis, with Staphylococcus aureus being the most common. Other common causative organisms include Kingella Kingae, Streptococcus pneumonia, Klebsiella species, Salmonella, Brucella melitensis, and Haemophilus influenzae.

Question 16

Figure 36 shows the hip arthrogram of a newborn. Which of the following structures is enclosed by the circle?

Explanation

DISCUSSION: The structure enclosed by the circle is the acetabular labrum. It is visible as the white point of tissue outlined by the darkly radiopaque contrast. The appearance of the contrast surrounding the sharp white point of a normal labrum is called the “rose thorn sign.” The limbus is the term reserved for a rounded, infolded labrum seen with arthrography. The pulvinar is the fatty tissue seen in the empty acetabulum when the hip is dislocated. The ligamentum teres is seen as a white stripe outlined by contrast coursing from the central acetabulum to the dislocated femoral head. The transverse acetabular ligament courses across the inferior portion of the acetabulum and is not clearly seen with arthrography.
REFERENCES: Herring JA: Tachdjian’s Pediatric Orthopaedics, ed 3. Philadelphia, PA,

WB Saunders, 2002, vol 1, pp 532-533.
Severin E: Contribution to the knowledge of congenital dislocation of the hip joint.

Acta Chir Scand 1941;84:1.

Question 17

A 65-year-old woman presents with neck pain for 18 months. She has taken NSAIDs and undergone physical therapy without improvement. Over the past 6 months, she has also noticed progressive hand clumsiness and difficulty with gait. Sagittal and axial MRI images are shown in figures A and B, respectively. What is the most appropriate next step in management? Review Topic

Explanation

This patient presents with clinical and radiographic evidence of cervical myelopathy with progression of gait imbalance and hand clumsiness. The most appropriate management is anterior cervical discectomy and fusion (ACDF).
Cervical myelopathy is typically caused compression on the spinal cord and classically present with neck pain, parasthesias, clumsiness, gait imbalance, and/or urinary retention. Nonoperative management is reserved for patients without functional impairment. ACDF is the treatment of choice for focal compression from anterior disc-ostephyte changes. Posterior decompression is indicated in patients with multi-level disease. It is important to note in patients with significant kyphosis, the kyphosis must be reversed in order for decompression alone to be effective.
Hsu reviewed posterior decompression techniques in the cervical spine. They state that the choice of anterior versus posterior approach is determined based on sagittal spine alignment, extent and location of pathological involvement, and patient preference. They recommend laminectomy and fusion for cervical stenosis and kyphosis <10 degrees. The use of BMP-2 as an adjunct in the cervical spine is not recommended by the author.
Emery reviewed cervical spondylotic myelopathy and recommend nonoperative treatment in patients with minimal symptoms without pathologic reflexes or gait imbalances. They suggest that the preferred posterior techniques are now laminectomy and fusion or laminoplasty.
Figure A and B are sagittal and axial T2 MRI sequences showing a degenerative disc osteophyte complex at C5-C6 with resultant canal stenosis and cord compression. Illustration A is a lateral C spine radiograph in a patient who is status post ACDF at C5-C6.
Incorrect Answers:

Question 18

An 11-year-old girl is struck in the leg by a loaded sled while sledding and is seen in the emergency department; she is reporting severe knee pain. Radiographs are read as normal. Examination reveals that she is exquisitely tender over the proximal tibial physis. The neurovascular examination is normal. What is the next step in management?

Explanation

DISCUSSION: The anatomic lesion in this patient is not exactly defined, but she has most likely sustained an injury about the knee. A Salter-Harris type I proximal tibial physeal fracture is likely. The normal radiograph reading can be misleading because these injuries may displace and spontaneously reduce. The child is at risk of compartment syndrome although she is currently not displaying signs of it. Thus, even though this injury may seem trivial by radiographic findings, it should be treated like a knee dislocation with a risk of late developing compartment syndrome. MRI or CT may be necessary to define the injury. She does not require emergent treatment, but merits close observation for possible compartment syndrome. Any of the possible injuries about the knee can be unstable and require internal fixation after reduction.
REFERENCES: McGuigan JA, O’Reilly MJ, Nixon JR: Popliteal arterial thrombosis resulting from disruption of the upper tibial epiphysis. Injury 1984;16:49-50.
Burkhart SS, Peterson HA: Fractures of the proximal tibial epiphysis. J Bone Joint Surg Am
1979;61:996- 1002.

Question 19

What neurovascular structure is in closest proximity to the probe in the arthroscopic view of the elbow shown in Figure 50? Review Topic

Explanation

The image shows a view of the radiocapitellar joint from an anterior medial portal. The radial nerve lies on the elbow capsule at the midportion of the capitellum. It is at risk for injury when capsular excision is performed in this region.

Question 20

A 28-year-old male sustains a midshaft fibula fracture after being kicked during a karate tournament and develops compartment syndrome isolated to the lateral compartment of his leg. If left untreated, which of the following sensory or motor deficits would be expected?

Explanation

DISCUSSION: The clinical vignette describes a scenario of isolated compartment syndrome in the lateral compartment of the leg. The only nervous structure residing in the lateral compartment is the superficial peroneal nerve. In compartment syndrome of the lateral leg compartment, failure of prompt surgical fasciotomy would present as a sensory deficit of the superficial peroneal nerve presenting as numbness on the dorsum of his foot involving the hallux, 3rd, and 4th toes, as seen in Illustration A.
Matsen et al discuss the poor results which can be a cause of late diagnosis and surgical decompression. They recommended compartment monitoring in equivocal cases as well as release of all four leg compartments when facing leg compartment syndrome. A diagram of a two-incision fasciotomy is shown in Illustration B.
Olson et al provide a review of compartment syndrome for the lower extremity. They discuss a variety of injuries and medical conditions may initiate acute compartment syndrome, including fractures, bleeding disorders, and other trauma. Although the diagnosis is primarily a clinical one, they also recommend supplementation with compartment pressure measurements in equivocal cases.

Question 21

A concussion diagnosis is made when there is

Explanation

YOUR RESPONSE: 3- a loss of consciousness for longer than 15 seconds. DISCUSSION
Neurocognitive testing is a helpful tool in the management of concussions, but testing does not independently determine if an athlete has experienced a concussion or when he or she can return to play. Neuroimaging findings typically are normal in concussive injury. Loss of consciousness occurs in fewer than 10% of patients with concussions. A concussion diagnosis is difficult to determine because of the lack of objective clinical and/or imaging findings. In general, a concussion is a disturbance in brain function caused by a direct or indirect force to the head.

RESPONSES FOR QUESTIONS 26 THROUGH 31
Plain radiographs
CT scan
MRI
Arthrogram
Which imaging method listed above is most appropriate for definitive diagnosis and management of each clinical scenario described below?

Question 22

A 25-year-old male polytrauma patient undergoes initial temporary external fixation for a femoral shaft fracture. He is converted to a femoral nail at 7 days. This management can be expected to result in

Explanation

DISCUSSION: Recently Harwood and associates investigated the principles of damage control orthopaedics (DCO) as they apply to patients with femoral shaft fractures. When they compared those who underwent initial external fixation of femoral shaft fractures with conversion to an intramedullary nail to those who underwent intramedullary nailing as their initial treatment, they found the following: overall infection rates were comparable in patients receiving DCO versus primary intramedullary fixation; open fracture was an independent risk factor for infection regardless of the treatment method; contamination rates in external fixator pin sites rose considerably when left in place more than 2 weeks and logistic regression analysis suggests that infection rates may increase when conversion to an intramedullary nail occurs after 2 weeks following external fixation; and there was no significant difference in time to union among treatment groups.
REFERENCES: Harwood PJ, Giannoudis PV, Probst C, et al: The risk of local infective complications after damage control procedures for femoral shaft fracture. J Orthop Trauma 2006;20:181-189.
Roberts CS, Pape HC, Jones AL, et al: Damage control orthopaedics: Evolving concepts in the treatment of patients who have sustained orthopaedic trauma. Instr Course Lect

2005;54:447-462.

Question 23

Longitudinal radioulnar dissociation, including Essex Lopresti fractures, requires disruption of the interosseous membrane (IOM). The interosseous membrane (IOM) consists of all of the following ligaments EXCEPT?

Explanation

DISCUSSION: The IOM includes 5 types of ligaments: central band, accessory band, distal oblique bundle, proximal oblique cord, and dorsal oblique accessory cord. The annular ligament is not a part of the IOM.
The IOM bridges the radius and ulna and acts as a hinge for rotation of radius about ulna. The central portion is thickened, and forms the central band which is the most important ligament for IOM load distribution characteristics.
Noda et al, in a cadaver study, identified the precise anatomical insertions and attachment points of each of the 5 IOM components. They found the most distal and proximal ends of the radial origin of the central band were 53% and 64% of total radial length from the tip of the radial styloid, whereas those of the ulnar insertion were 29% and 44% of total ulnar length from the ulnar head.
Pfaeffle et al also performed a cadaveric biomechanical study applying compressive loads to specimens with IOMs that are intact, cut, or cut/reconstructed with flexor carpi radialis allografts. They found that reconstruction of the IOM can restore the normal load transfer chararcteristics and that the central band of the IOM is the most important portion of the IOM to be reconstructed.

Question 24

Figure 12 shows a lateral radiograph of the elbow. What is the most likely diagnosis?

Explanation

DISCUSSION: The figure shows a supracondylar process, which is a normal anatomic variant. An osteochondroma tends to occur more toward the end of bones, and the medullary space of the underlying bone extends into the base of the osteochondroma. The presence of a supracondylar process is usually asymptomatic. However, the ligament of Struthers that always extends from the supracondylar process to the medial epicondyle can result in median nerve entrapment secondary to trauma.
REFERENCE: Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, pp 132-133.
Keats TE, Anderson MW: Atlas of Normal Roentgen Variants That May Simulate Disease, ed 7. St Louis, MO, Mosby Inc, 2001, p 497.

Question 25

A surgeon contemplates performing a hemiarthroplasty (HA) or total hip arthroplasty (THA) for an active, community ambulating 70-year-old female with a displaced femoral neck fracture. Which of the following is true for these options?

Explanation

THA has a higher perioperative complication rate than HA.
There are a few differences between THA and HA performed in the setting of displaced FNF. THA has a higher dislocation rate, greater blood loss, requires a larger exposure than HA, and the operation is longer. HA often requires reoperation because of progressive acetabular erosion. Patient outcomes and function are greater following THA than HA.
Florschultz et al. reviewed current management of FNF. They concluded that CRIF / ORIF is indicated for displaced femoral neck fractures in younger individuals, select active elderly, and medically unfit patients. HA is indicated for lower demand ambulatory older patients. THA is indicated for the active elderly and those with preexisting acetabular disease.
Avery et al. reviewed 7-10 year results of an RCT comparing THA with HA. More HA patients had died during follow-up. All surviving patients had polyethylene wear (THA) and acetabular erosion (HA). They concluded that there was lower mortality and a trend towards superior function in patients with a THA in the medium term.
Hedbeck et al. performed a RCT comparing HA and THA. At 4 years, there was improved function and quality of life with THA. They recommend THA in elderly, lucid patients with a displaced FNF.
Incorrect Answers:

Question 26

A 6-year-old Little League pitcher has had pain in the right elbow for the past 2 weeks. Examination reveals mild lateral elbow joint tenderness with full range of motion and no effusion or collateral laxity. A radiograph is shown in Figure 38. Initial management should consist of

Explanation

DISCUSSION: The radiograph shows osteochondritis dissecans (OCD) of the capitellum, one manifestation of “pitcher’s elbow.” The lesion is nondisplaced, and healing is possible if the inciting throwing activities are curtailed. Long arm cast treatment may be reasonable for the noncompliant patient but should not exceed 6 weeks duration. Surgical treatment is indicated for loose bodies or cartilage flaps. Elbow OCD lesions are now being seen in younger children as more participate in organized sports, especially baseball and gymnastics.
REFERENCES: Bauer M, Jonsson K, Josefsson PO, et al: Osteochondritis dissecans of the elbow: A long-term follow-up study. Clin Orthop 1992;284:156-160.
Takahara M, Ogino T, Sasaki I, et al: Long term outcome of osteochondritis dissecans of the humeral capitellum. Clin Orthop 1999;363:108-115.
Byrd JW, Jones KS: Arthroscopic surgery for isolated capitellar osteochondritis dissecans in adolescent baseball players: Minimum three-year follow-up. Am J Sports Med

2002;30:474-478.

Question 27

Figure 99 shows a dorsal approach for a midfoot arthrodesis following a Lisfranc injury in a 43-year-old woman. The base of the second metatarsal is labeled with the letter B. The interval used to create this exposure is

Explanation

DISCUSSION
The interval shown is between the extensor hallucis longus (left) and the extensor hallucis brevis (right), which is not an internervous plane because both are innervated by the deep peroneal nerve. The neurovascular bundle is under the extensor hallucis brevis muscle. Both
muscles are innervated by branches of the deep peroneal nerve. The superficial peroneal

Question 28

-Figures 14a through 14d are the radiographs and sagittal T1- and T2-weighted MRI scans of an otherwise healthy 10-year-old girl who has experienced 3 weeks of worsening pain with weight bearing and is now refusing to bear weight to either of her lower extremities. She denies any history of injury or trauma.She has not had any fevers or recent illnesses. She denies any numbness or parasthesias. She has had no bowel or bladder incontinence. In the emergency department she is afebrile and tender to palpation over the midlumbar spine. She has pain with hyperextension and flexion of her back. Her white blood cell count is 11.4 (reference range, 4.5-11.0 x109/L), erythrocyte sedimentation rate is 40 mm/h (reference range, 0-20 mm/h), and C-reactive protein is 2.6 mg/L (reference range, 0.08-3.1 mg/L). What is the most appropriate course of action at this time?

Explanation

Question 29

Metal-on-metal lumbar disk arthroplasty devices may generate cobalt and chromium ions into the serum of patients after implantation into the lumbar spine. Which of the following statements best represents the levels of the serum ion levels in these patients? Review Topic

Explanation

According to two studies looking at patients with a cobalt-chrome metal-on-metal lumbar disk arthroplasty, serum ion levels in these patients were similar to values measured in patients with total hip arthroplasty metal-on-metal prostheses.

Question 30

A patient who underwent total knee arthroplasty 6 years ago now reports knee pain for the past 3 days following dental surgery. Cultures of the aspirate are positive for Staphylococcus epidermidis. Management should consist of

Explanation

DISCUSSION: The patient has an early prosthesis infection as a result of hematogenous seeding from dental surgery. Irrigation and debridement with polyethylene exchange and IV antibiotics have been successful in early postoperative infections; it is less likely to be effective for a late hematogenous infection. Immediate total component exchange also may be effective, but it should be reserved for failure of irrigation and debridement.
REFERENCES: Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 323-337.
Goldman RT, Scuderi GR, Insall JN: 2-stage reimplantation for infected total knee replacement. Clin Orthop 1996;331:118-124.

Question 31

Which of the following acetabular cup designs has shown the greatest survivorship at 10 years in patients younger than age 60 years?

Explanation

DISCUSSION: Poor survivorship of cemented sockets in young patients has lead to the development of a variety of cementless designs. Of these, smooth metal-backed sockets have not performed as well as porous-coated designs. Threaded metal-backed sockets showed a 6% to 25% revision rate secondary to aseptic loosening at a mean follow-up of 4.5 to 6 years. Despite some early failed designs, cementless porous-coated metal-backed sockets have shown the best survivorship in long-term studies.
REFERENCES: Smith SE, Harris WH: Total hip arthroplasty performed with insertion of the femoral component with cement and the acetabular component without cement: Ten to thirteen-year study. J Bone Joint Surg Am 1997;79:1827-1833.
Pellicci PM, Tria AJ Jr, Garvin KL, (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 195-206.

Question 32

An 11-year-old boy reports the acute onset of elbow pain and swelling after pushing his brother. The patient's mother and a younger sibling have experienced numerous fractures. You note that the patient and his mother have blue sclera and normal-appearing teeth. A radiograph of the elbow is shown in Figure 60. This patient's disorder is most likely the result of Review Topic

Explanation

Osteogenesis imperfecta (OI) is a genetically determined disorder of type I collagen synthesis characterized by bone fragility. This patient sustained a displaced fracture of the olecranon apophysis after relatively minor trauma. Physical examination reveals distinctly blue sclera. His mother and younger sibling have experienced numerous fractures suggesting a family history of bone fragility. The patient's history, clinical features, and family history are consistent with a diagnosis of Sillence type I-A OI. Type I OI is the mildest and most common form. Inheritance is autosomal dominant.
Type I is subclassified into the A type (absence of dentinogenesis imperfecta) and B type (presence of dentinogenesis imperfecta). These individuals have blue sclerae, and although the initial fracture usually occurs in the preschool years, it may occur at any age. Furthermore, olecranon apophyseal fractures that occur after relatively minor trauma have been associated with type I OI. Cells from individuals with type I OI largely demonstrate a quantitative defect of type I collagen; they synthesize and secrete about half the normal amount of type I procollagen. In this patient, there are no indications that the child has been subjected to abuse. Radiographs of the elbow show no evidence of osteopetrosis (due to abnormal osteoclast function) or rickets (due to a deficiency of vitamin D). Morquio syndrome (characterized by a defect of the enzyme N-Ac-Gal-6 sulfate sulfatase) is not associated with blue sclera.

Question 33

While performing a total shoulder arthroplasty, excessive retraction is placed on the "strap muscles" (short head of biceps and coracobrachialis). Neurovascular examination would reveal weakness of which of the following? Review Topic

Explanation

The musculocutaneous nerve can be as close as 3 cm to the coracoid process; therefore, this relationship is important to keep in mind when performing surgery in
this area. Excessive traction on the musculocutaneous nerve could lead to a neurapraxia with resultant weakness of elbow flexion and forearm supinaton because of the loss of biceps function.

Question 34

A 17-year-old girl who initially presented as a child with multiple skeletal lesions, café-au-lait spots, and precocious puberty now has bone pain. A recent bone scan reveals multiple areas of increased scintigraphic uptake, including bilateral proximal femurs. A radiograph is shown in Figure 19. Besides activity modification, what is the next best line of treatment for decreasing her pain? Review Topic

Explanation

McCune-Albright syndrome is the combination of polyostotic fibrous dysplasia, café-au-lait lesions, and endocrine dysfunction. The most common endocrine presentation is precocious development of secondary sexual characteristics. Compared with bone lesions in patients without polyostotic disease, the skeletal lesions in patients with the syndrome tend to be larger, more persistent, and associated with more complications. Bisphosphonate therapy has been shown in several studies to decrease the pain associated with the skeletal lesions of fibrous dysplasia.

Question 35

A 22-year-old woman injured her ankle when she fell off a ladder. Radiographs reveal a displaced large posterior malleolus fracture of about 45% of the joint. What is the best definitive treatment?

Explanation

Basic understanding of fracture care requires a fundamental knowledge of the principles regarding absolute and relative stability. Compression plating and anatomic reduction of articular fractures are examples of absolute stability. Bridge plating, external fixation, casting, and intramedullary nailing are all examples of relative stability. Both bone forearm fractures have long been treated with open reduction and internal fixation even in the light of open wounds. Results have been excellent with plate fixation. Recently, intramedullary nails that are contoured and locked have been used in the treatment of both bone forearm fractures, but they are not reamed. It is well established that with restoring the proper radial bow, length, and alignment,
optimal function can be achieved. Open reduction and internal fixation allows this achievement. In cases where comminution exists, absolute stability may have to be sacrificed so as to not strip small comminuted bone fragments. Therefore, a bridging technique is worthwhile. External fixation can be used as a temporary technique until the soft tissues are more amenable to definitive fixation. Cast treatment is not indicated in adult forearm fractures. Locking nails for forearm use are not reamed. With regards to articular fractures, anatomic reduction and rigid stabilization are required to achieve the best results and allow for fracture healing. This environment also allows for the best chance of the cartilage repair process to form "hyaline-like" cartilage. Open reduction and internal fixation with absolute stability is the mainstay of treatment for partial articular fractures such as split depression tibial plateau fractures and posterior malleolus fractures involving greater than about 25% to 30% of the joint. The gold standard for the treatment of a closed femur fracture is a reamed intramedullary locked nail. Results are uniformly excellent. This can be done without stripping of the soft tissues such as in open reduction and internal fixation. External fixation can be used as a temporary device in patients in extremis for damage control reasons.Moed BR, Kellam JF, Foster RJ, Tile M, Hansen ST Jr. Immediate internal fixation of open fractures of the diaphysis of the forearm. J Bone Joint Surg Am. 1986 Sep;68(7):1008-17. http://www.ncbi.nlm.nih.gov/pubmed/3745238')">View Abstract at PubMedJones DB Jr, Kakar S. Adult diaphyseal forearm fractures: intramedullary nail versus plate fixation. J Hand Surg Am. 2011 Jul;36(7):1216-9. Epub 2011 May

Question 36

Figures 163a through 163c show the radiograph and MRI scans of a 45-year-old woman with severe right arm pain. She has had symptoms for 6 months without resolution despite multiple nonsurgical treatments. Examination reveals weakness in the right triceps and wrist flexors with decreased sensation in the middle finger and a positive Spurling's sign. What is the most appropriate treatment for the patient's symptoms? Review Topic

Explanation

The patient has symptoms and signs of cervical radiculopathy despite a long course of nonsurgical management. Therefore, surgical decompression is indicated and is best performed through an anterior cervical diskectomy and arthrodesis. Single level anterior cervical diskectomy and arthrodesis have been shown to produce significant improvements in arm pain and neurologic function. Anterior cervical foraminotomy, while reported, has insufficient data to support its use and it places the vertebral artery at significant risk. Posterior cervical foraminotomy is contraindicated given the ventral spinal cord compression; foraminotomy places the patient at risk for spinal cord injury. The patient has one-level cervical disease, therefore a corpectomy is unnecessary. Posterior laminoplasty is used to treat myelopathy, not radiculopathy.

Question 37

In performing an opening wedge high tibial osteotomy at the tibial tubercle, the osteotome extends 5 mm posteriorly and centrally out of the bone as shown in Figures 17a and 17b. What is the first structure it enters?

Explanation

DISCUSSION: The major risk of performing a high tibial osteotomy is neurovascular injury. The new version of the high tibial osteotomy makes a transverse osteotomy at the level of the tibial tubercle. The osteotome is protected by the oblique belly of the popliteus muscle. The popliteal artery and vein and tibial nerve all lie posterior to the muscle. The soleus muscle originates below this level.
REFERENCES: Clement CD: Anatomy: A Regional Atlas of Human Anatomy, ed 3.

Baltimore, MD, Munich, Germany, Urban and Schwarzberg, 1987, Figure 422.
Netter FH: Atlas of Human Anatomy. Summit, NJ, Ciba-Geigy, 1989, plate 480.

Question 38

A 17-year-old boy underwent open reduction and internal fixation of a navicular fracture 5 days ago. A follow-up examination now reveals a tensely swollen foot with erythema and multiple skin bullae. The patient is febrile and has marked pain with palpation of the entire forefoot and hindfoot. What is the next step in management?

Explanation

DISCUSSION: Necrotizing fasciitis is a rapidly progressive soft-tissue infection with the potential to threaten both life and limb. Patients who are immunocompromised (HIV infection, diabetes mellitus, alcohol abuse) are at increased risk. However, any patient in the immediate postoperative phase is susceptible to wound infection. Early detection is the key. Necrotizing fasciitis is primarily a surgical problem that requires urgent debridement and broad-spectrum IV antibiotics. Rapid diagnosis and prompt treatment help to reduce mortality, which may approach 30%. Debridement of the bullae and observation are not indicated. Although elevation and close follow-up may be warranted early on, in this patient, surgical debridement is the next step.
REFERENCES: Ault MJ, Geiderman J, Sokolov R: Rapid identification of group A streptococcus as the cause of necrotizing fasciitis. Ann Emerg Med 1996;28:227-230.
McHenry CR, Piotrowski JJ, Pentrinic D, Malangoni MA: Determinants of mortality for necrotizing soft-tissue infections. Ann Surg 1995;221:558-563.

Question 39

A 40-year-old man sustains a scapular body fracture after an all-terrain vehicle accident. Which of the following is the most commonly associated injury?

Explanation

Chest injury (rib fracture, pneumothorax, hemothorax, contusion) is the most commonly associated injury in patients who have sustained a significant scapular injury. Chest injury becomes even more commonly found when the scapula has more than one zone of injury (ie, multiple fractures). Humeral fracture, clavicle fracture, and axillary nerve injury are not as common as chest injury.

Question 40

Sacral fractures are most likely to be associated with neurologic deficits when they involve what portion of the sacrum?

Explanation

DISCUSSION: Denis divided the sacrum into three zones: zone 1 represents the lateral ala, zone 2 represents the foramina, and zone 3 represents the central canal. A fracture is classified according to its most medial extension. Those in zone 3 are typically bursting-type fractures or fracture-dislocations and are most prone to neurologic sequelae.
REFERENCES: Denis F, Davis S, Comfort T: Sacral fractures: An important problem.

A retrospective analysis of 236 cases. Clin Orthop Relat Res 1988;227:67-81.
Wood KB, Denis F: Fractures of the sacrum and coccyx, in Vacarro AR (ed): Fractures of the Cervical, Thoracic and Lumbar Spine. New York, NY, Marcel Dekker, 2003, pp 473-488.

Question 41

A displaced pediatric supracondylar humerus fracture is treated with closed manipulation and placement of 2 Kirschner wires placed from the lateral side. What would be the effect of adding a third pin from the lateral side? Review Topic

Explanation

Multiple biomechanical studies have shown that the addition of a third pin from the lateral side improves construct stiffness in the presence of medial column loss or slight internal rotation of the distal fragment. The same studies show that addition of a medial pin (cross pinning) has essentially the same benefit. Placement of a medial pin increases risk for iatrogenic nerve injury.

Question 42

A 17-year-old football player continues to have discomfort after sustaining a blow to his midthigh during a game 8 weeks ago. A plain radiograph is shown in Figure 13. What is the most appropriate management?

Explanation

DISCUSSION: The patient has myositis ossificans. Rest of the involved area is important to help limit the continued irritation of the muscle, but range-of-motion exercises are important to limit stiffness. While immobilization for 1 or 2 days following a muscle contusion is appropriate, longer periods of immobilization result in muscle atrophy and fibrosis. Injections and irradiation have not been found to be of benefit for myositis ossificans. Excision is rarely required, and if performed, it should not be performed prior to maturation of the lesion, which is a minimum of 6 months.
REFERENCES: Lipscomb AB, Thomas ED, Johnston RK: Treatment of myositis ossificans traumatica in athletes. Am J Sports Med 1976;4:111-120.
Beiner JM, Jokl P: Muscle contusion injuries: Current treatment options. J Am Acad Orthop Surg 2001;9:227-237.
Ryan JB, Wheeler JH, Hopkins WJ, et al: Quadriceps contusions: West Point update. Am J Sports Med 1991;19:299-304.

Question 43

A 23-year-old man sustained an injury to his left foot when a forklift rolled over it at work. Examination reveals marked swelling of the midfoot and forefoot, with tenderness to palpation over the medial hindfoot and dorsomedial forefoot. The distal dorsalis pedis pulse is audible on Doppler examination, and his sensation is intact to touch. Radiographs are shown in Figures 33a and 33b. Management should consist of

Explanation

DISCUSSION: The best results after dislocations of the tarsometatarsal joints are seen with anatomic reduction; this is best achieved by open reduction and maintained with internal fixation with either pins or screws. Open reduction provides a means of debriding small bony fragments from the joint and allowing direct inspection of the reduction. Associated crush or shearing fractures of the cuboid or tarsal navicula are signs that suggest a Lisfranc injury. Because patients can function quite well despite the development of arthrosis in the Lisfranc joint, primary arthrodesis is not indicated in the management of this injury.
REFERENCES: Resch S, Stenstrom A: The treatment of tarsometatarsal injuries. Foot Ankle 1990;11:117-123.
Schenck RC Jr, Heckman JD: Fractures and dislocations of the forefoot: Operative and nonoperative treatment. J Am Acad Orthop Surg 1995;3:70-78.
Kuo RS, Tejwani NC, Digiovanni CW, et al: Outcome after open reduction and internal fixation of Lisfranc joint injuries. J Bone Joint Surg Am 2000;82:1609-1618.

Question 44

Initial repair of the large U-shaped rotator cuff tear shown in Figure 12 consists of closing the tear side-to-side to take advantage of margin convergence. The most significant biomechanical consequence of this repair step results in

Explanation

DISCUSSION: Margin convergence refers to the phenomenon that occurs with side-to-side closure of large U- or L-shaped rotator cuff tears in which the free margin of the tear converges toward the greater tuberosity as the side-to-side tear progresses. The creation of the converged cuff margin creates decreased strain in the free margin of the repaired cuff, resulting in a decreased strain in the repair sutures. While the size of the humeral head defect is made smaller with side-to-side closure, biomechanically, this is less significant. The mild increase in thickness of the repair at the side-to-side margin is less important than a reduction in stress in the repaired tissue. Stress in the crescent cable region of the cuff actually increases and becomes more physiologic in transmitting force from the cuff to the greater tuberosity.
REFERENCES: Burkhart SS: A stepwise approach to arthroscopic rotator cuff repair based on biomechanical principles. Arthroscopy 2000;16:82-90.
Burkhart SS, Athanasiou KA, Wirth MA: Margin convergence: A method of reducing strain in massive rotator cuff tears. Arthroscopy 1996;12:335-338.

Question 45

Collagen orientation is parallel to the joint surface in what articular cartilage zone?

Explanation

DISCUSSION: The collagen orientation changes from parallel in the superficial zone to a more random pattern in the middle zone and finally to perpendicular in the calcified zone.
REFERENCES: Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 498-499.
Mankin HJ, Mow VC, Buckwalter JA: Articular cartilage structure, composition, and function, in Einhorn TA, O’Keefe RJ, Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006,

in press.

Question 46

Figure 199 is the clinical photograph of a 68-year-old man with a history of atrial fibrillation who was treated with warfarin. Nine days after undergoing elective total hip arthroplasty, he has a swollen left thigh. His wound remains dry and he is afebrile. His erythrocyte sedimentation rate (ESR) is 25 mm/h (reference range [rr], 0-20 mm/h) and C-reactive protein (CRP) level is 6.1 mg/L (rr, 0.08-3.1 mg/L). Aspiration reveals 3246 white blood cells (WBCs)/µL with 47% polymorphonucleocytes. Treatment at this time should consist of

Explanation

DISCUSSION
This patient has a large postsurgical hematoma. Although his ESR and CRP level are elevated, they are not considered elevated given his recent surgery. Additionally, the hip aspiration reveals a synovial cell count lower than 10000 WBC/µL along with a low percentage of polymorphonucleocytes. Treatment at this time should consist of observation. The hematoma is likely attributable to postsurgical anticoagulation, considering his history of atrial fibrillation.

Question 47

Figure 11 shows the radiograph of an otherwise healthy 22-year-old man who sustained a midfoot injury in a motor vehicle accident 9 days ago. Treatment should consist of

Explanation

DISCUSSION: The dislocation is between the medial and middle cuneiform. Although the first and second tarsometatarsal joints are aligned, there is a gap between the cuneiforms. The radiograph shows a Lisfranc dislocation variant. In a healthy active individual, open reduction and internal fixation yields the best results. The reestablishment of the normal arch and medial column support with anatomic reduction is critical to obtaining the best possible outcome from these injuries.
REFERENCES: Teng AL, Pinzur MS, Lomasney L, et al: Functional outcome following anatomic restoration of the tarsal-metatarsal fracture dislocation. Foot Ankle Int

2002;23:922-926.
Kuo RS, Tejwani NC, DiGiovanni CW, et al: Outcome after open reduction and internal fixation of Lisfranc joint injuries. J Bone Joint Surg Am 2000;82:1609-1618.

Question 48

What ligament is the primary restraint to applied valgus loading of the knee?

Explanation

DISCUSSION: The superficial portion of the MCL contributes 57% and 78% of medial stability at 5 degrees and 25 degrees of knee flexion, respectively. The deep MCL and posteromedial capsule act as secondary restraints at full knee extension. The anterior cruciate ligament and PCL also provide secondary resistance to valgus loads.
REFERENCE: Garrett WE, Speer KP, Kirkendall DT (eds): Principles & Practice of Orthopaedic Sports Medicine. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, p 767.

Question 49

Figure 8 shows the radiograph of a 76-year-old man who has knee pain and swelling. History reveals that he underwent total knee arthroplasty 18 years ago. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiograph reveals complete loss of joint space with particulate metal debris consistent with total polyethylene failure and metal-on-metal articulation. The components appear to be well fixed and minimal osteolysis is evident.
REFERENCES: Kilgus DJ, Moreland JR, Finerman GA, et al: Catastrophic wear of tibial polyethylene inserts. Clin Orthop Relat Res 1991;273:223-231.
Vince KG: Why knees fail. J Arthroplasty 2003;18:39-44.

Question 50

A 69-year-old woman reports a painful clicking in her right shoulder. A soft-tissue mass is palpated at the lower portion of the scapula. Based on the MRI scan and biopsy specimens shown in Figures 72a through 72c, what is the most likely diagnosis?

Explanation

DISCUSSION: Elastofibroma is a rare, benign soft-tissue pseudotumor characteristically located in the subscapular region. Most patients are between 50 and 70 years of age and have pain, decreased shoulder range of motion, or a mass. The lesion usually is best visualized with the arm elevated forward and adducted to displace the scapula laterally and allow the mass to protrude from the chest wall. They are frequently bilateral. Grossly, the mass is ill-defined, oblong or spherical, firm, and ranges in size from 5 cm to 10 cm. These masses appear infiltrative and frequently are mistaken for a sarcomatous lesion. Histologically, the mass is composed of a mixture of intertwining eosinophilic collagen and elastic fibers, and scattered fibroblasts, mucoid material, and fat.
REFERENCES: Vastamaki M: Elastofibroma scapulae. Clin Orthop Relat Res 2001;392:404-408.
Nielsen T, Sneppen O, Mykre-Jensen O, et al: Subscapular elastofribroma: A reactive pseudotumor. J Shoulder Elbow Surg 1996;5:209-213.
Weiss SW, Goldblum JR, Enzinger FM: Enzinger and Weiss’s Soft Tissue Tumors, ed 4. Philadelphia, PA, Elsevier, 2001, pp 286-289.

Question 51

What is the usual mechanism of injury for the fracture shown in Figures 49a and 49b?

Explanation

Figures 49a and 49b show a severely comminuted, displaced fracture of the distal tibial metaphysis with intra-articular extension, i.e. pilon fx, or the so-called “distal tibial explosion fracture.” According to the article by Kellam JF and Waddell JP, there are “two mechanisms that can cause this fracture, a rotational pronation dorsiflexion force, and an axial compression force with the foot in either neutral or dorsiflexion at the moment of impact. Because of these mechanisms of injury, two fracture patterns were observed in the series of patients reported. The rotational pattern results in several large metaphyseal fragments, and usually a fibular fracture of a short oblique type above the level of the ankle joint…The second and unfortunately the more common fracture pattern is caused by a severe axial compression force which causes marked comminution of the distal tibial metaphysis, loss of bone substance due to impaction, superior migration of the talus, and loss of the ankle cartilage space.”

Question 52

A 52-year-old, right hand dominant man comes for evaluation of right shoulder pain that has been intermittently bothering him for three months. The pain is worse with overhead activities. He denies any history of trauma. His range of forward elevation in the plane of the scapula is painful and is limited to 145 degrees, compared to 170 degrees on his unaffected side. A radiograph is shown in Figure A. He saw another orthopedist a month ago, who ordered an MRI, which showed a small, partial thickness supraspinatus tendon tear. He received a subacromial injection of lidocaine at that time which temporarily relieved 90 percent of the pain he felt with passive forward elevation of his shoulder past 90 degrees. Today he is requesting a subacromial injection of platelet rich plasma (PRP). You tell him that with regard to pain, function and range of motion, subacromial injection of PRP: Review Topic

Explanation

At one year, quality of life, pain, disability and shoulder range of motion are the same for patients treated with therapy and placebo versus patients treated with therapy and
PRP injection.
Platelet rich plasma has been used for the treatment of chronic tendinopathy in different areas with mixed results. No benefit to patients with symptoms of subacromial impingement has been demonstrated for subacromial injection of PRP, when added to a standard therapy program.
Kesikburun et al. conducted a randomized controlled trial in which patients with rotator cuff tendinopathy or partial rotator cuff tears were randomized to receive ultrasound-guided subacromial injection of either PRP or lidocaine, followed by a standard six-week therapy program. The authors found no difference in pain, range of motion or validated outcome scores at one year follow up.
Hall et al. reviewed sports medicine applications for PRP. At that time (2009), with regard to PRP, they concluded that there was "little clinical evidence for its use."
Ketola et al. sought to determine the effectiveness of subacromial decompression for the treatment of subacromial impingement syndrome. They randomized 140 patients to a supervised exercise program or arthroscopic subacromial decompression followed by a supervised exercise program. They found no clinically important differences between the two groups at 24 months follow up.
Figure A shows a right shoulder radiograph without osseous pathology. Incorrect answers:

Question 53

A football player who injured his right lower extremity during a game could not get up and reported extreme pain. The initial sideline evaluation showed a probable anterior cruciate, posterior cruciate, and lateral collateral ligament rupture with a very unstable knee. He also reports pain in his ankle and is unable to dorsiflex the ankle. He has limited sensation over the dorsum of his foot. Examination reveals no swelling of the ankle and no pain with passive range of motion of the ankle. What is the most likely diagnosis? Review Topic

Explanation

It is not uncommon to sustain a peroneal nerve injury in association with a knee dislocation or multi-ligament injury. There should always be a high index of suspicion for this injury, and the vascular status to the leg should be carefully evaluated. From the history and examination, there is no indication that the ankle was fractured. A compartment syndrome will not develop within a few minutes of the injury. It takes several hours for a compartment syndrome to develop and become symptomatic. The tibial nerve supplies the plantar aspect of the foot. An acute rupture of the tibialis anterior tendon in a young person is very uncommon, and it is associated with pain and localized swelling about the ankle. It is also unlikely that it would lead to sensory loss.

Question 54

Which of the following post-reduction forearm fractures patterns may be treated non-operatively in an otherwise healthy 22-year old male?

Explanation

In adults, minimally displaced fractures of the ulna may be treated non-operatively.
Even in the setting of minimal displacement, fractures involving the radial diaphysis, or both bones of the forearm, are at high risk of displacing further and progressing to malunion or nonunion. Given the potential for a resulting loss of forearm rotation, open reduction internal fixation is indicated for almost all adult diaphyseal radius and both bone fractures.
Schulte et al. review the management of both bone forearm fractures in adults. They review biomechanics, fixation techniques, outcomes and complications. They note that the goals of fixation in simple patterns are 'cortical opposition, compression, and restoration of forearm geometry.'
Anderson et al. treated 330 acute diaphyseal forearm fractures with compression plating from 1960 to 1970. At 4 months to 9 years follow up, they achieved a 97.9%
union rate for the radius and 96.3% union rate for the ulna.
Illustration A shows measurement of radial bow. A dotted line perpendicular to the line drawn from the radial tuberosity to the ulnar aspect of the distal radius can be used to measure radial bow when drawn at the point of maximum distance to the ulnar edge of the radius.
Incorrect answers:

Question 55

What does Dual Energy X-ray Absorptiometry (DEXA) testing, as a technique, measure?

Explanation

DISCUSSION: DEXA can provide data on bone mineral content and soft-tissue composition, and requires cross-sectional dimension for accuracy. DEXA provides a quantitative, not qualitative, measurement of bone mineral content and is incapable of differentiating between trabecular and cortical bone. Osteoarthritis falsely elevates the values, especially in the AP spinal analysis.
REFERENCES: Genant HK, Faulkner KG, Gluer CC: Measurement of bone mineral density: Current status. Am J Med 1991;91:49S-53S.
Genant HK, Engelke K, Fuerst T, et al: Review: Noninvasive assessment of bone mineral density and stature: State of the art. J Bone Miner Res 1996;11:707-730.
Engelke K, Gluer CC, Genant HK: Factors influencing short-term precision of dual X-ray bone absorptiometry (DXA) of spine and femur. Calcif Tissue Int 1995;56:19-25.

Question 56

What structure is considered the single most important soft-tissue restraint to anterior-posterior stability of the sternoclavicular joint?

Explanation

DISCUSSION: In a cadaver ligament sectioning study, the posterior capsular ligament was considered the most important structure for anterior-posterior stability of the sternoclavicular joint. The anterior capsular ligament also helps prevent anterior displacement but not to the same degree as the posterior ligament. The interclavicular ligament provides little support for anteroposterior translation.
REFERENCES: Spencer EE, Kuhn JE, Huston LJ, et al: Ligamentous restraints to anterior and posterior translation of the sternoclavicular joint. J Shoulder Elbow Surg 2002;11:43-47.
Rockwood CA Jr, Matsen FA III, Jobe CM: Gross Anatomy of the Shoulder. Philadelphia, PA, WB Saunders, 1998.

Question 57

A 21-year-old male is brought to the emergency department after being involved in gang-related violence. A radiograph of his pelvis is shown in Figure A. The patient is hemodynamically stable. Which of the following imaging modalities is the next best step in evaluating this patient for the most common associated injury? Review Topic

Explanation

Low velocity gunshot wounds (GSW) to the hip are most commonly associated with bowel perforation. Consultation with general surgery (or in some facilities, trauma surgery) is necessary to exclude this.
The incidence of GSW is increasing and it is the 2nd leading cause of death in young males in the US after motor vehicle accidents. The incidence of a GSW to the buttock is approximately 8% of all GSW to the extremities. Potential complications of pelvic and acetabular GSW include septic arthritis, enterocutaneous, enteroacetabular, and vesicoacetabular fistulas, infected nonunion, malunion, and injuries to the iliac vessels. The presence or absence of intra-abdominal injuries affects treatment and outcome.
Bartkiw et al. reviewed 2808 GSW and found 1235 associated fractures including 42 fractures of the hip and pelvis. Ten orthopaedic operative procedures were performed in 7 patients. Associated nonorthopaedic injuries included 15 small/large bowel perforations (36%), 7 vessel lacerations (17%), and 2 urogenital injuries (5%) that required surgery.
Najibi et al. reviewed 39 GSW to acetabulum. They found 32 simple and 7 associated fracture patterns. The most common simple and associated patterns were anterior column and both column, respectively. Bowel injuries were the most common associated injures (42%). Predictors of poor outcome include high-velocity missile, involvement of acetabular dome, abdominal injury, nerve injury, vascular injury, and male gender. Deep infection was associated with primary anastomosis of bowel injury and an associated fracture pattern.
Figure A shows a GSW to the right hip with acetabular fracture and visible bullet fragment.
Incorrect Answers:

Question 58

A 14-year-old boy has had knee pain for the past 2 months. He also has a low-grade fever of 101.3 degrees F (38.5 degrees C). Laboratory studies show a WBC count of 12,100/mm 3 and an erythrocyte sedimentation rate of 58/h. A biopsy specimen of a lesion in the distal femoral metaphysis is shown in Figure 38. What is the most appropriate treatment?

Explanation

DISCUSSION: The clinical presentation of this patient is consistent with both acute osteomyelitis and Ewing’s sarcoma. Both entities can be noted in the distal femoral metaphysis although Ewing’s sarcoma is classically noted in the diaphysis. The histology reveals a mixed inflammatory cell infiltrate with neutrophils, plasma cells, lymphocytes, and histiocytes. Ewing’s sarcoma would be a uniform population of small round blue cells without an inflammatory component. Eosinophilic granuloma (EG) is characterized by Langerhans histiocytes and eosinophils. Treatment of EG often consists of an intralesional steroid injection. Treatment of acute osteomyelitis includes surgical debridement and antibiotics.
REFERENCES: McCarthy JJ, Dormans JP, Kozin SH, et al: Musculoskeletal infections in children: Basic treatment principles and recent advancements. Instr Course Lect 2005;54:515-528.
Calhoun JH, Manring MM: Adult osteomyelitis. Infect Dis Clin North Am 2005;19:765-786.

Question 59

A 30-year-old man who participates in recreational sports reports the spontaneous onset of intermittent pain and swelling about the right knee. Examination reveals a 3+ effusion, with a range of motion of 10° to 60°. He has mild diffuse tenderness but no instability. MRI scans and an arthroscopic view are shown in Figures 39a through 39c. Management should consist of

Explanation

DISCUSSION: The patient has synovial chondromatosis. The MRI scans show multiple small proscribed areas of signal intensity in the gutters and suprapatellar pouch, suggesting very small loose bodies. The arthroscopic view shows the classic appearance of multiple small chondral loose bodies. Synovial chondromatosis is a condition in which the synovium undergoes metaplasia, producing multiple chondral loose bodies that can subsequently ossify. The treatment of choice, removal of the loose bodies and arthroscopic synovectomy, results in a lower incidence of recurrence than other treatment methods.
REFERENCES: Coolican MR, Dandy DJ: Arthroscopic management of synovial chondromatosis of the knee: findings and results in 18 cases. J Bone Joint Surg Br

1989;71:498-500.
Ogilvie-Harris DJ, Saleh K: Generalized synovial chondromatosis of the knee: A comparison

of removal of the loose bodies alone with arthroscopic synovectomy. Arthroscopy

1994;10:166-170.

Question 60

Figures 1 and 2 are the MR arthrogram images of a 16-year-old, right-hand-dominant baseball player who injured his left shoulder 4 weeks ago during a game. He now has pain, weakness, and the inability to swing a bat and can no longer do push-ups. He denies prior injury to his left shoulder. Radiographs are unremarkable. Which of the four muscles of the rotator cuff provides the most resistance to this patient's direction of instability?

Explanation

Posterior shoulder instability is a rare form of instability that often presents with pain rather than feelings of instability. It often occurs in young athletes during activities that put the shoulder in an “at-risk position” (flexion, adduction, internal rotation). Repetitive microtrauma can lead to posterior shoulder instability such as seen in football linemen. Swinging a bat or golf club places the lead arm in a flexed, adducted, and internally rotated position, which can lead to posterior translation of the humeral head that is forcibly reduced in follow-through, as seen in this patient. The glenohumeral joint relies on static and dynamic stabilizers. Static stabilizers help prevent instability at the end ranges of motion when the ligaments are taut. Dynamic stabilizers work to prevent subluxation at midranges of motion, at which the ligaments are lax. The rotator cuff is integral as a dynamic stabilizer of the shoulder. It works through a process called concavity compression. The four muscles of the rotator cuff compress the humeral head into the concavity of the glenoid-labrum. This prevents the humeral head from subluxing during the midranges of motion. Of the four rotator cuff muscles, the subscapularis is most important at preventing posterior subluxation. This patient has posterior instability, and various surgical techniques may be indicated depending on findings. Arthroscopic labral repair is indicated for anterior instability. Arthroscopic posterior labral repair is indicated for this patient because he has a posterior labral tear and posterior instability. If a patient has ligamentous laxity (not seen in this scenario because sulcus and Beighton sign findings would be negative), a posterior capsular shift with rotator interval closure is
indicated. If a patient has excessive glenoid retroversion (not seen in this scenario with 5 degrees of retroversion), a posterior opening-wedge osteotomy is appropriate.

Question 61

A 45-year-old IV drug abuser has sternoclavicular (SC) joint pain for the past 2 weeks. He is afebrile and physical exam findings include point tenderness and swelling. He most likely has septic arthritis of the sternoclavicular joint. If so, what is the most likely infecting organism?

Explanation

DISCUSSION: Risk factors for sternoclavicular septic arthritis include IV drug abuse, diabetes, and HIV.
According to the reference by Ross et al, Staphylococcus aureus accounts for 49% of infections. SC joint arthritis accounts for 1% of septic arthritis in the general population but 17% in the IV drug abuse population. Symptoms include spontaneous swelling with the appearance of joint subluxation and localized pain. These patients are not uncommonly afebrile.

Question 62

.What is the most appropriate treatment if instability is present at the time of evaluation?

Explanation

Question 63

Figure 46 shows the radiograph of an obese 12-year-old boy who has had left hip pain for the past 3 months. What is the best course of action?

Explanation

DISCUSSION: The patient has an obvious slipped capital femoral epiphysis of the left hip for which the recommended treatment is percutaneus pinning in situ. Development of a contralateral slip is less likely at this age; therefore, observation of the right hip is indicated because there is no general agreement regarding prophylactic fixation. Typically, there is no role for spica casting. Physical therapy is not indicated as a primary treatment, and reduction is contraindicated, as it has been associated with osteonecrosis.
REFERENCES: Loder RT, Aronsson DD, Greenfield ML: The epidemiology of bilateral slipped capital femoral epiphysis: A study of children in Michigan. J Bone Joint Surg Am 1993;75:1141-1147.
Aronsson DD, Karol LA: Stable slipped capital femoral epiphysis: Evaluation and management. J Am Acad Orthop Surg 1996;4:173-181.
Hurley JM, Betz RR, Loder RT, Davidson RS, Alburger PD, Steel HH: Slipped capital femoral epiphysis: The prevalence of late contralateral slip. J Bone Joint Surg Am 1996;78:226-230.
Loder RT, Aronson DD, Dobbs MB, Weinstein SL: Slipped capital femoral epiphysis. J Bone Joint Surg Am 2000;82:1170-1188.

Question 64

A 30-year-old man has pain in the left arm after a motor vehicle accident. His neurovascular examination is intact, and radiographs are shown in Figures 25a and 25b. What is the best course of management?

Explanation

DISCUSSION: The floating elbow is best managed with early open reduction and internal fixation of the humeral and forearm fractures, followed by early range of motion. These fractures predispose the elbow to stiffness, and early range of motion is recommended.
REFERENCES: Solomon HB, Zadnik M, Eglseder WA: A review of outcomes in 18 patients with floating elbow. J Orthop Trauma 2003;17:563-570.
Yokoyama K, Itoman M, Kobayashi A, et al: Functional outcomes of “floating elbow” injuries in adult patients. J Orthop Trauma 1998;12:284-290.

Question 65

A year-old man with a body mass index of 31 had a month gradual onset of right medial knee pain. Examination revealed a small effusion, stable ligaments, a normally tracking patella, and mild medial joint line tenderness. Standing radiographs show mild medial joint space narrowing. Effective treatment at this stage of early medial compartmental osteoarthritis includes

Explanation

DISCUSSION:
According to the 2008 AAOS Clinical Practice Guideline, Treatment of Osteoarthritis of the Knee (Nonarthroplasty), level 1 evidence confirms that weight loss and exercise benefit patients with knee osteoarthritis. The other responses have either inclusive evidence (a valgus-directing brace) or no evidence to support their use (glucosamine 1,500 mg/day and chondroitin sulfate 800 mg/day as well as
arthroscopic debridement and lavage).

Question 66

Which of the following structures is predominantly composed of Type 1 collagen? Review Topic

Explanation

The most common fiber type in the Anterior cruciate ligament is Type 1 collagen.
Type 1 collagen accounts for more than 90% of the total collagen content in the body. Type 1 collagen is found in bone, ligament, tendon, meniscus, annulus of intervertebral discs, skin, healed cartilage, scar tissue, and nerves.
Duthon et al present a review of the ACL and its histologic and mechanical properties. The ACL has a mean length of 32 mm and a width of 7-12 mm. They state that the ACL has a microstructure of collagen bundles of multiple types (mostly type I) and a matrix made of a network of proteins, glycoproteins, elastic systems, and glycosaminoglycans with multiple functional interactions.
Incorrect
1: Epithelial
2: L4 disc
Basement
Membrane is made up of Type
nucleus pulposus is composed of mostly Type
4 collagen.
2 collagen
4: Medial femoral condyle articular cartilage is comprised mostly of Type 2 collagen. 5: Dupuytren's contracture tissue is mostly Type 3 collagen.

Question 67

Figure 1 is an MRI scan of the right hip of a 19-year-old woman with a 6-month history of right groin pain. She was diagnosed with a stress fracture and was treated with 3 months of limited weight bearing. Figure 2 is a repeat MRI scan in which the edema pattern changed minimally but the pain worsened. Ibuprofen alleviates most of her pain. What is the best next step?

Explanation

An osteoid osteoma is a benign bone tumor. Osteoid osteomas tend to be small—typically <1.5 cm. Regardless of their size, they cause a large amount of reactive bone to form around them, and they make a new type of abnormal bone material called osteoid bone. This osteoid bone, along with the tumor
cells, forms the nidus of the tumor, which is easily identified on CT scans.

Question 68

Which of the following areas of the vertebral segment has the highest ratio of cortical to cancellous bone? Review Topic

Explanation

The weight-bearing potential of bone is influenced by the ratio of cortical to cancellous bone. The area of the spinal anatomy that has the highest ratio is the pedicles of the thoracic spine. This is followed by the lumbar pedicles. The vertebral bodies have a lower ratio than the pedicles, with the sacrum having the very lowest ratio.

Question 69

What structure provides the major blood supply to the humeral head?

Explanation

DISCUSSION: The ascending branch of the anterior circumflex humeral artery provides

the major blood supply to the humeral head. The posterior circumflex humeral artery

supplies a much smaller portion of the proximal humerus. The nutrient humeral artery is the main blood supply for the humeral shaft. The thoracoacromial artery is primarily a muscular branch. The rotator cuff insertions contribute some blood supply to the tuberosities but not a major contribution.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.
Cushner MA, Friedman RJ: Osteonecrosis of the humeral head. J Am Acad Orthop Surg 1997;5:339-346.

Question 70

What spinal nerves in the cauda equina are primarily responsible for innervation of the bladder?

Explanation

DISCUSSION: The spinal nerves primarily responsible for bladder function are the S2, S3, and S4 nerve roots. With significant compression of the cauda equina by either disk herniation, tumor, or degenerative stenosis, bladder dysfunction may result.
REFERENCES: Hoppenfeld S: Physical Examination of the Spine and Extremities. Norwalk, CT, Appleton-Century-Crofts, 1976, p 254.
Pick TP, Howden R (edS): Gray’s Anatomy. New York, NY, Bounty Books, 1977, p 1004.

Question 71

..Further imaging shows pulmonary metastases without an obvious primary tumor of origin and an incomplete fracture of the right distal femur. A decision is made to surgically treat his distal femur fracture. What is the role of establishing a preoperative histologic diagnosis for this patient?

Explanation

t(12;22)(q13;q12-3)
t(X;18)(p11.2;q11.2)
t(11;22)(q24;q12)
t(1;3)(p36.3;q25)

Question 72

A 14-year-old boy has had a 3-month history of low back pain with no known trauma. The pain is worse with activity and relieved by rest, although he does report difficulty with prolonged sitting in school. The patient was on the football team but stopped participating because of the back pain during football practice. He reports no history of radicular pain and denies any numbness, tingling, or weakness in the legs. Neurologic examination is normal. Back examination reveals slight tenderness over the lower back area but no swelling or skin defects. Strength testing is 5 over 5 in the lower extremities and the straight leg raise test is negative. Back range of motion is nearly full, but back extension is painful. The hamstrings are slightly tight. Initial radiographs, including AP, lateral and oblique views, are negative. What is the best test to determine the patient's diagnosis? Review Topic

Explanation

A bone scan with SPECT is very sensitive and specific for spondylolysis not seen on initial radiographs. MRI can sometimes visualize spondylolysis, but it is not as sensitive nor as specific as a bone scan with SPECT. Flexion and extension views
have no role in the evaluation of the patient who presents with classic spondylolysis-type symptoms. The most sensitive physical examination finding is pain with back extension. Oblique radiographs can be obtained, but they are not as sensitive or specific as a bone scan with SPECT. The patient does not have any signs of a disk problem; therefore, an evaluation of the disk is not helpful.
(SBQ13PE.79) A 17-year-old male American football lineman presents with low back pain of insidious onset that is somewhat worse with activity. He has no neurologic complaints, night pain or fevers. His symptoms have been present for a few years but this is the first time he has sought medical attention. What physical examination finding is most likely to be found in this clinical scenario? Review Topic
Popliteal angle of 5 degrees
Heel cord tightness
Increased femoral anteversion
Pain with lumbar extension in single leg stance
Numbness of the skin of the anterolateral calf and dorsum of the foot
The patient demographics and clinical presentation are consistent with lumbar spondylolysis. Pain with lumbar extension is the most common physical exam finding.
Office assessment of the patient with spondylolysis should note pertinent negatives that would signify other causes of back pain. The history is most commonly negative for neurologic symptoms such as weakness or numbness, although patients will occasionally have radicular pain. On exam, patients may have localized spasm or tenderness, step off (if there is spondylolisthesis), hamstring tightness. The most common finding is pain with lumbar extension.
McCleary et al. review the diagnosis and treatment of spondylolysis in athletes. They identify three types of patients with spondylolysis: (1) female dancer or gymnast who is hyperlordotic, with increased motion and flexibility, (2) male weightlifter or football player undergoing a growth spurt, with decreased motion and flexiblity, especially of the spinal erectors, and (3) a novice athlete undergoing vigorous preparation for a new sport, with poor core strength and flexibility.
Incorrect

Question 73

A 30-year-old patient has acetabular dysplasia and moderate secondary osteoarthrosis. Which of the following studies will best help predict the success of periacetabular osteotomy?

Explanation

DISCUSSION: Improvement in the appearance of the hip joint on functional radiographic evaluation (abduction/adduction views) has been shown to be predictive of outcome following joint preserving surgery. CT and MRI findings have not been shown to be predictive of outcome.
REFERENCE: Murphy S, Deshmukh R: Periacetabular osteotomy: Preoperative radiographic predictors of outcome. Clin Orthop 2002;405:168-174.

Question 74

A patient with rheumatoid arthritis with both ankle and subtalar involvement was treated as shown in Figures 11a and 11b. What complication is unique to this type of fixation?

Explanation

DISCUSSION: The interlocking screws at the proximal end of the rod can act as a stress riser and lead to fracture. Postoperative pain at this level should prompt inclusion of this diagnosis in the differential. Removing the screws following bone union can decrease the chances of this occurring. A short rod that avoids the diaphyseal area may also be beneficial. Rotatory deformity is controlled by the perpendicularly oriented distal transfixion screws. Talar osteonecrosis would be unusual since the dissection can be minimized with an intramedullary rod. Any type of hardware can fail if the construct does not lead to a solid arthrodesis.
REFERENCES: Nunley JA, Pfeffer GB, Sanders RW, et al (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 236-237.
Thordarson DB, Chang D: Stress fractures and tibial cortical hypertrophy after tibiotalocalcaneal arthrodesis with an intramedullary nail. Foot Ankle Int 1999;20:497-500.
Hammett R, Hepple S, Forster B, et al: Tibiotalocalcaneal (hindfoot) arthrodesis by retrograde intramedullary nailing using a curved locking nail: The results of 52 procedures. Foot Ankle Int 2005;26:810-815.

Question 75

A 38-year-old woman has a lesion on her left foot that has increased in size over the past 6 months. The clinical photograph is shown in Figure 17a, and a photomicrograph of the biopsy specimen is shown in Figure 17b. What is the most likely diagnosis?

Explanation

DISCUSSION: Melanoma comprises 25% of lower extremity lesions and is the most common malignant tumor of the foot. The preferred treatment is wide resection.
REFERENCES: Hughes LE, Horgan K, Taylor BA, Laidler P: Malignant melanoma of the hand and foot: Diagnosis and management. Br J Surg 1985;72:811-815.
Fortin PT, Freiberg AA: Malignant melanoma of the foot and ankle. J Bone Joint Surg Am 1995;77:1396-1403.

Question 76

What structure is 7cm from the acromion and at greatest risk of injury during a deltoid splitting approach for a proximal humerus fracture?

Explanation

DISCUSSION: The axillary nerve is located approximately 7cm from the tip of the acromion. The axillary nerve comes off the of the brachial plexus (middle trunk, posterior division, posterior cord) carrying fibers from C5 and C6. The axillary nerve travels through the quadrangular space with the posterior circumflex humeral artery and vein to innervate the teres minor and deltoid muscles and supply sensation over the lateral shoulder.
Based on the knowledge of the course of the axillary nerve, and potential complications regarding the
vascular supply to the humeral head with the delto-pectoral approach, some authors are suggesting deltoid-splitting approach to the proximal humerus for reduction and fixation of proximal humeral fractures.
Cetik et al evaluated 24 cadaver shoulders to better identify the course of the axillary nerve and identify the "safe zones" for deltoid-splitting incisions. They found the distance from the tip of the acromion to the axillary nerve varied depending on patient specific factors like arm length and they identified a "safe area" where dissection was free of injury to the axillary nerve (Illustrations A and B).

Question 77

Antegrade femoral nailing has an increased rate of which of the following when compared to retrograde femoral nailing?

Explanation

DISCUSSION: In the referenced study by Ricci et al, antegrade femoral nailing was shown to have an increased rate of hip pain as compared to retrograde femoral nailing, while having a similar rate of union, time to union, rate of malalignment, and operative time. Hip pain was signficantly higher in the antegrade nailing group, while knee pain
was significantly greater in the retrograde group. The referenced study by Winquist et al noted a 99.1% union rate with intramedullary nailing. The referenced study by Moed et al noted a 6% nonunion rate in non-reamed retrograde femoral nailing with nail dynamization at 6-12 weeks and early weightbearing.

Question 78

Posttraumatic physeal arrest is most common at which of the following locations?

Explanation

DISCUSSION: Posttraumatic physeal arrest occurs most commonly in the distal medial tibia. Using MRI, Echlund and associates confirmed this finding. Arrest of the distal radius and proximal humerus are rare after trauma. Traumatic injuries of the distal femoral and distal ulnar physis have a high incidence of growth arrest as well.
REFERENCES: Ecklund K, Jaramillo D: Patterns of premature physeal arrest: MR imaging of 111 children. AJR Am J Roentgenol 2002; 178:967-972.
YAtotoartanadQpyiQter GN: Physeal bridge resection. J Am Acad Orthop Surg 2005; 13:4

Figure 64a Figure 64b

Question 79

Figures A-C are images of a 37-year-old man who presents with isolated muscle atrophy due to a compressed nerve. Which of the following sequences correctly describes the pathway of this nerve through the brachial plexus, before it innervates the affected muscles?

Explanation

Figures A-C shows atrophy of teres minor and deltoid due to compression of the axillary nerve. The correct pathway of the axillary nerve within the brachial plexus is, C5-C6 nerve roots; upper trunk, posterior division, posterior cord.
Quadrilateral space syndrome is a condition defined by axillary nerve, +/- posterior humeral circumflex artery compression in the quadrilateral space. It most commonly affects the dominant shoulder in overhead movement athletes (e.g. basketball players) or other throwing athletes. Physical examination may reveal weakness with the arm positioned in abduction and external rotation. In situations of long-standing compression, there may also be atrophy of the teres minor and deltoid muscle.
Chafik et al. dissected thirty-one cadaveric human shoulders to describe the neuromuscular anatomy of teres minor. They showed that the primary nerve branch to teres minor travelled in a fascial sling 44 mm medial to the muscular insertion. This
area may be the potential site of greatest compression and tethering of this nerve in patients with isolated teres minor atrophy.
Friend et al. performed a cadaveric dissection of nine shoulder specimens to look at the anatomical variability in course, length and branching pattern of both the teres minor nerve and the axillary nerve. These were compared to a case-based study of these two male patients with isolated atrophy of teres minor. They concluded that there is no good anatomical predictor of nerve compression outside the quadrilateral space as there is considerable anatomical variation in its origin and course, as well as potential site of compression.
Figure A-C are MRI images that show atrophy of the teres minor muscle and possibly deltoid muscle. The rotator cuff muscles are labeled in Illustration A. The teres minor muscle is labeled in Illustration B. Illustration C shows a diagram of the brachial plexus.
Incorrect
1:
This
describes
the
musculocutaneous
nerve.
3:
This
describes
the
suprascapular
nerve.
4:
This
describes
the
long thoracic
nerve.

Question 80

Your 25-year-old patient complains of anterior knee pain after retrograde femoral nailing for a diaphyseal fracture and asks you why you didn’t perform antegrade nailing as he has seen on the internet. You tell him that retrograde nailing is your preferred technique over antergrade nailing for diaphyseal femoral fractures because it has been shown to have?

Explanation

DISCUSSION: Patients with retrograde femoral nails commonly have knee pain, while antegrade nails commonly have hip pain, abductor weakness and heterotopic ossification of the abductors. Ostrum’s randomized prospective study of 100 patients with reamed femoral nails found 22% of antegrade nail patients had proximal hip pain, weak hip abductors or trendelenburg gait. No significant difference was found in set-up time, operative time, knee motion or pain, or infection rates. Ricci performed a retrospective study of 293 fractures and found that the antegrade femoral nail group had more hip pain (10% vs 4%) and the retrograde nail group had more knee pain (36% vs 9%). There was no difference in healing, malunion, non-union or other complications. Tornetta performed a randomized controlled comparison of 69 femur fractures and found more problems of length and rotation using a retrograde nailing. There was no difference in time to union, operating time, blood loss, complications, size of nail or reamer, or transfusion requirements

Question 81

A 9-year-old child has right groin pain after falling from a tree. Examination reveals that the right leg is held in external rotation, and there is significant pain with attempts at passive range of motion. Radiographs are shown in Figures 43a and 43b. Management should consist of

Explanation

DISCUSSION: The complications of femoral neck fractures in children include osteonecrosis, malunion, nonunion, and premature physeal closure. It is presumed that the risk of osteonecrosis is directly related to the amount of displacement at the time of injury and is not affected by the type of treatment. The risk of the other complications can be decreased depending on the type of treatment. Anatomic reduction by either closed or open methods can reduce the risk of malunion. The addition of internal fixation allows for maintenance of the reduction. In young children who cannot comply with a partial or non-weight-bearing status, the addition of a spica cast gives added protection.
REFERENCES: Canale ST: Fractures of the hip in children and adolescents. Orthop Clin North Am 1990;21:341-352.
Hughes LO, Beaty JH: Fractures of the head and neck of the femur in children. J Bone Joint Surg Am 1994;76:283-292.

Question 82

An 18-year-old patient sustains a comminuted left femoral fracture starting 6.5cm distal to the lesser trochanter. He undergoes antegrade femoral nailing in the supine position on a radiolucent table. Upon completion of proximal and distal interlocking, both patellae are positioned facing the ceiling and a lateral radiographs confirms that the posterior condyles of both limbs are aligned. On AP imaging of both femora, it is noted that the lesser trochanter of the left (injured) side is larger than the right (uninjured) side. Assuming symmetrical anteversion, the left femur has been nailed Review Topic

Explanation

Pulmonary embolus
Periprosthetic fracture
Contralateral hip fracture
Osteonecrosis
Infection
This young male patient has sustained a displaced femoral neck fracture and underwent open reduction internal fixation with 3 cannulated screws. Based on the available options, the patient is most at risk of developing osteonecrosis of the femoral head.
Femoral neck fractures in young patients typically are the result of a high-energy trauma. Fracture displacement has been shown to disrupt vascular supply to the femoral head by interrupting retinacular vessels and ligament teres vascularization, as well as increasing intracapsular pressure, producing a tamponade effect. The incidence of osteonecrosis in patients younger than 60 years with displaced femoral neck fractures has been shown to be between 15-30%. Quality of reduction is one key factor that has been shown to influence outcomes postoperatively.
Loizou et al. prospectively studied 1,023 patients who sustained an intracapsular hip fracture that was treated with internal fixation using standard fixation modalities. They showed that osteonecrosis was less common for undisplaced (4.0%) than for displaced fractures (9.5%). The population at greatest risk were women younger than the age of 60 with displaced fractures.
Barnes et al. review subcapital hip fractures. They found that late segmental collapse was more common in displaced fractures in women younger than age 75 years than in those older than age 75 years treated with internal fixation.
Figure A shows a displaced, Garden 3/Pauwels I hip fracture. Figure B shows anatomical fixation with 3 cannulated screws.
Incorrect Answers:

Question 83

In Ewing’s sarcoma, neoplastic properties are thought to be related to a

Explanation

DISCUSSION: In 95% of patients with Ewing’s sarcoma, there is a translocation, t(l 1:22). This results in EWS/FLI-1 transcription factor that results in tumor cell proliferation. Other mechanisms causing
tumor cell proliferation include inactivation of tumor suppressor genes, or activation of proto-oncogenes.
REFERENCES: Arndt CA, Crist WM: Common musculoskeletal tumors of childhood and adolescence. N Engl J Med 1999;341:342-352.
Pierz KA, Womer RB, Dormans JP: Pediatric bone tumors: Osteosarcoma Ewing’s sarcoma, and chondrosarcoma associated with multiple hereditary osteochondromatosis. J Pediatr Orthop 2001
;21:412- 418.

Question 84

Figure 93 shows the axial T2-weighted MRI scan of the lumbar spine of a 70-year-old man. The arrow points to which of the following structures? Review Topic

Explanation

The ligamenta flava (singular, ligamentum flavum, Latin for yellow ligament) are ligaments that connect the laminae of adjacent vertebra, all the way from the axis to the first segment of the sacrum. In T2-weighted sequencing, ligamentous structures possess a low signal intensity. The ligamentum in this patient is markedly thickened, resulting in severe spinal stenosis. The epidural space lies ventral and medial to the ligamentum flavum and should possess a high signal intensity secondary to the presence of cerebrospinal fluid. However, in the case of high-grade stenosis, there may be little if any cerebrospinal fluid present, making the epidural space and central canal difficult to identify. A lumbar synovial cyst should also have high signal intensity because of the presence of synovial fluid.
(SBQ12SP.14) A 36-year-old male presents with acute onset of right buttock and leg pain following lifting a heavy object. On physical exam he has weakness to knee extension, numbness over the medial malleolus, and a decreased patellar reflex. Which of the following would most likely explain this clinical presentation. Review Topic
Lumbar arachnoiditis
L4/L5 paracentral disc herniation
L3/L4 far lateral (foraminal) disc herniation
L4/L5 far lateral (foraminal) disc herniation
L5/S1 far lateral (foraminal) disc herniation
The clinical presentation is consistent with a L4 radiculopathy. A L4/L5 far lateral (foraminal) disc herniation would compress the exiting root (L4) and cause these symptoms.
The location of a prolapsed lumbar disc determines its symptoms. Central disc herniations may give rise to back pain or cauda equina syndrome. Paracentral disc herniations (90-95% of cases) affect the traversing nerve root. Far lateral disc herniations (5-10%) affect the exiting nerve root.
Gregory et al. summarize physical signs in lumbar disc herniation. They state that the straight-leg-raise is the most sensitive (73-98% sensitive) test and the crossed straight-leg-raise is the most specific (88-98% specific) test for lumbar disc herniation. Other specific tests include weak ankle dorsiflexion (89% specific), absent ankle reflex (89% specific), and calf wasting (94% specific, but a late finding).
Illustration A shows how a paracentral L4/L5 disc herniation affects the traversing L5 root, but a far lateral L4/L5 disc herniation affects the L4 root. Illustration B shows the dermatomal distribution of pain with root involvement from L3 to S1.
Incorrect Answers:

Question 85

Which of the following is the only nonreversible effect of anabolic steroids?

Explanation

DISCUSSION: The loss of hair or alopecia, is the only nonreversible effect of anabolic steroid use.
Once anabolic steroids are stopped, muscle hypertrophy and training gains are quickly lost and the HDL/ LDL ratios return to their preexisting levels. Fortunately, the personality effects and the acute acne are reversible.
REFERENCES: Hartgens F, Kuipers H: Effects of androgenic-anabolic steroids in athletes. Sports Med 2004;34:513-554.
Evans NA: Current concepts in anabolic-androgenic steroids. Am J Sports Med 2004;32:534-542.

Question 86

A 16-year-old snowboarder has significant pain and is still unable to bear weight after sustaining a lateral ankle injury in a fall 1 week ago. Examination reveals swelling and tenderness in the sinus tarsi. AP, lateral, and mortise radiographs of the ankle are unremarkable. Management should consist of

Explanation

DISCUSSION: Because there is a significant possibility that the patient may have a fracture of the lateral process of the talus, there is some disagreement as to the best radiographic study to identify this injury. A CT scan is an appropriate diagnostic tool to visualize the fracture and identify any displacement. Displaced lateral process fractures are best treated surgically.
REFERENCES: Kirkpatrick DP, Hunter RE, Janes PC, Mastrangelo J, Nicholas RA: The snowboarder’s foot and ankle. Am J Sports Med 1998;26:271-277.
Ebraheim NA, Skie MC, Podeszwa DA, Jackson WT: Evaluation of process fractures of the talus using computed tomography. J Orthop Trauma 1994;8:332-337.

Question 87

A 10-year-old girl with a history of an obstetrical brachial plexus palsy has been referred for evaluation. Examination reveals a severe adduction internal rotation contracture of the shoulder and a mild flexion contracture of the elbow. Hand function is normal. Radiographs show mild glenohumeral joint incongruity. To achieve the best functional outcome, management should consist of

Explanation

DISCUSSION: The patient has an upper plexus palsy (Erb palsy) with severe shoulder contracture. While physical therapy for stretching is the treatment of choice to prevent contracture in the newborn, it is unlikely to be of benefit in the older child with an established contracture. Contracture release alone or in combination with muscle transfers can improve the cosmetic appearance, and in the case of a mild deformity, may also improve function. These procedures are less likely to help when there is deformity of the shoulder joint or when arthritic changes are present. The procedure of choice for an older child with joint deformity is rotational osteotomy of the proximal humerus because it can improve cosmesis and function, even in the face of joint deformity.
REFERENCES: Jahnke AH Jr, Bovill DF, McCarroll HR Jr, James P, Ashley RK: Persistent brachial plexus birth palsies. J Pediatr Orthop 1991;11:533-537.
Strecker WB, McAllister JW, Manske PR, Schoenecker PL, Dailey LA: Sever-L’Episcopo transfers in obstetrical palsy: A retrospective review of 20 cases. J Pediatr Orthop 1990;10:442-444.
Goddard NJ, Fixsen JA: Rotation osteotomy of the humerus for birth injuries of the brachial plexus. J Bone Joint Surg Br 1984;66:257-259.

Question 88

A 12-year-old girl who plays softball has chronic lateral hindfoot aching pain that is aggravated by weight-bearing activity. She reports that the pain has recurred after initial improvement with cast immobilization, and it continues to limit her overall level of activity. Radiographs are seen in Figures 40a through 40c. What is the most appropriate surgical treatment?

Explanation

DISCUSSION: The patient has a calcaneonavicular tarsal coalition. Symptoms of calcaneonavicular coalitions typically are seen between the ages of 10 and 14 years. The cause of pain has not been clearly established. It has been postulated that the coalition stiffens with maturity and microfractures can result, producing pain. Resection of a calcaneonavicular coalition generally has been associated with a satisfactory result. Soft-tissue interposition, most commonly using the extensor digitorum brevis muscle, appears to be helpful. A hindfoot arthrodesis (usually triple) would be reserved if coalition resection proves to be unsuccessful. Achilles tendon lengthening and orthotic support, as well as debridement of the sinus tarsi, are not expected to result in a satisfactory outcome. The patient does not have a flatfoot deformity.
REFERENCES: Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 757-765.
Lemley F, Berlet G, Hill K, et al: Current concepts review: Tarsal coalition. Foot Ankle Int 2006;27:1163-1169.

Question 89

The medial collateral ligament complex of the elbow originates on what portion of the medial epicondyle?

Explanation

DISCUSSION: The medial collateral ligament complex of the elbow consists of three portions: the anterior bundle, the posterior bundle, and a transverse component that has little biomechanic significance. The origin of the ligament is from the central two thirds of the anteroinferior undersurface of the medial epicondyle.
REFERENCE: O’Driscoll SW, Jaloszynski R, Morrey BF: Origin of the medial ulnar collateral ligament. J Hand Surg Am 1992;17:164-168.

Question 90

A 30-year-old woman injured the ring finger of her nondominant hand while playing baseball 5 weeks ago. She now reports pain and limited motion of the proximal interphalangeal (PIP) joint. A lateral fluoroscopy image is shown in Figure 36. Treatment of the PIP joint should consist of

Explanation

DISCUSSION: The patient has a neglected PIP joint fracture-dislocation with comminution involving more than 40% of the volar articular surface of the middle phalanx. Volar plate arthroplasty has been advocated for the treatment of acute unstable and chronic dorsal fracture-dislocations. The volar plate is incised laterally and released from the collateral ligaments. The volar fragments of the middle phalanx are removed and a trough is created for advancement of the volar plate, which is secured with sutures secured on the dorsum of the middle phalanx beneath the extensor mechanism.
REFERENCES: Dionysian E, Eaton RG: The long-term outcome of volar plate arthroplasty of the proximal interphalangeal joint. J Hand Surg Am 2000;25:429-437.
Eaton RG, Malerich MM: Volar plate arthroplasty of the proximal interphalangeal joint: A review of ten years’ experience. J Hand Surg Am 1980;5:260-268.
Deitch MA, Kiefhaber TR, Comisar BR, et al: Dorsal fracture dislocations of the proximal interphalangeal joint: Surgical complications and long-term results. J Hand Surg Am 1999;24:914-923.

Question 91

03 What is the most common site of fracture because of osteolysis following cementless total hip arthroplasty with an extensively porus-coated femoral component?

Explanation

Again referenced article is not helpful. Here is the thought process. Porous coating allows for bony ingrowth, and

creates stress shielding. The force is seen through the femoral head into the stem and transfers to the bone at areas of
ingrowth and transmitted distally. As a result the part being skipped is the greater trochanter and leads to osteolysis by Wolf’s law and can result in fracture.

The osteolysis created about the acetabulum is due an inflammatory mechanism imparted on the wear debris from the bearing surfaces. This osteolysis rarely creates fractures.

The fractures about the stem are most commonly caused by the difference in modulus between the stem and bone back to this question next question

Question 92

A 17-year-old male soccer player sustains repeated lateral patellar dislocations refractory to physical therapy, bracing, and taping. After a workup including radiographs and MRI, the orthopaedic surgeon considers an isolated tibial tubercle osteotomy (TTO). He plans a 60-degree anteromedialization to address instability and to unload the patellofemoral joint. What is a relative contraindication to this procedure?

Explanation

CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 41
A healthy, active 18-year-old man has acute-onset right knee pain and an inability to fully extend his knee following an attempt to stand from a seated position yesterday. He sustained a noncontact injury to his right knee while playing basketball 2 years ago and underwent primary anterior cruciate ligament (ACL) reconstruction with bone-patella-tendon-bone autograft and medial meniscus repair. He sustained another noncontact injury to the same knee 8 months later and underwent a revision ACL reconstruction using soft-tissue allograft and revision medial meniscus repair. He reports multiple episodes of “giving way” of his knee, but no pain prior to yesterday’s acute injury.

Question 93

The patient undergoes a mobile-bearing UKA. When compared to a fixed-bearing metal-backed unicompartmental arthroplasty, this procedure is associated with a

Explanation

DISCUSSION
A patient with medial compartment arthritis and a correctable varus deformity with no clinical or examination findings of knee instability most likely has an intact ACL. The pattern of medial compartment osteoarthritis most commonly associated with an intact ACL is that of anteromedial osteoarthritis. An incompetent ACL is commonly associated with a fixed varus deformity and radiographic signs of posteromedial wear. An incompetent ACL is a relative contraindication to a mobile-bearing UKA. When evaluating patients for a mobile-bearing UKA, a stress radiograph will allow the orthopaedic surgeon to determine the correction of the varus deformity and assess the lateral compartment. Inability to fully correct the deformity or narrowing of the lateral compartment with valgus stress should influence the surgeon against UKA. Joint registries across the world have shown decreased survivorship associated with TKA and UKA in men compared to other age groups, but survivorship is lower for UKA than TKA. No studies to date have shown differences in survivorship between fixed- or mobile-bearing UKAs. The complication that is unique to mobile-bearing UKA is bearing spinout, and this occurs in fewer than 1% of mobile-bearing UKA procedures. In vivo and in vitro polyethylene wear in mobile-bearing UKA is low. Arthritis progression may be faster for mobile-bearing UKAs than fixed-bearing UKAs.
The radiographs reveal a fracture of the extensively porous coated stem. This entity, although rare, is associated with higher risk for occurrence when thin stems are implanted in patients with thick cortices and there is a lack of proximal stable support for the prosthesis. Nonsurgical care likely would not help this patient. A triple-phase bone scan would not add any information that would change the treatment plan.

Question 94

A 60-year-old man who underwent left partial knee arthroplasty 6 months earlier was doing well until he experienced left knee pain and swelling for 4 weeks following a dental procedure. The left knee aspirate was bloody, with a white blood cell count of 8,000 and 70% neutrophils. Culture grew group B Streptococcus ( Granulicatella adiacens ), and serologies were elevated, with an erythrocyte sedimentation rate of 55 mm/h (reference range: 0 to 20 mm/h) and a C-reactive protein level of 24 mg/L (reference range: 0.08 to 3.1 mg/L). What is the best next step?

Explanation

DISCUSSION:
This complication is best addressed with either a single-stage or two-stage total knee arthroplasty. A recent report suggests that a single-stage arthroplasty can be effective, although many surgeons would perform a two-stage procedure with an articulating or static spacer. Arthroscopic would be non-effective, especially given 4 weeks of symptoms. Resection arthroplasty without a spacer would leave an unstable and poorly functioning extremity. Knee fusion should be used as a salvage procedure.

Question 95

Figure 43 shows the lateral radiograph of a 12-year-old boy with mild osteogenesis imperfecta who injured his left elbow after pushing his brother. Treatment should consist of

Explanation

DISCUSSION: The patient has a displaced fracture of the apophysis of the olecranon for which most authorities recommend surgical treatment. In older children, stability of the reduction may be achieved by the use of two parallel medullary Kirschner wires and a figure-of-8 tension band loop of either stainless steel wire or absorbable suture. The use of an absorbable suture does not require removal of the implant. Absorbable suture alone is best used in very young patients who have this type of injury. An intramedullary screw would pose an unnecessary risk of future growth disturbance.
A displaced, isolated fracture of the apophysis of the olecranon is an unusual injury in a child. It has been suggested by several authors that children who have osteogenesis imperfecta may be especially prone to this injury. One study reported seven of these fractures occurring in five children who had the mild form of osteogenesis imperfecta (Sillence type IA). The authors of this study suggest that the diagnosis of osteogenesis imperfecta be considered in any child who has a displaced fracture of the apophysis of the olecranon, especially when the injury is associated with relatively minor trauma.
REFERENCES: Stott NS, Zionts LE: Displaced fractures of the apophysis of the olecranon in children who have osteogenesis imperfecta. J Bone Joint Surg Am 1993;75:1026-1033.
Gaddy BC, Strecker WB, Schoenecker PL: Surgical treatment of displaced olecranon fractures in children. J Pediatr Orthop 1997;17:321-324.
Dormans JP, Rang M: Fractures of the olecranon and radial neck in children. Orthop Clin North Am 1990;21:257-268.

Question 96

A patient with diabetic peripheral neuropathy undergoes a partial first ray amputation for a chronic ulcer beneath the first metatarsal head. The insertion of the anterior tibialis is preserved. The patient has 10 degrees of passive dorsiflexion at the ankle and no other foot deformities or ulcers. Which of the following is considered appropriate shoe wear for this patient?

Explanation

DISCUSSION: The steel shank is a flat 1-inch steel strip placed between layers of the shoe to extend the foot lever and prevent deformity at the toe break seen following a partial first ray amputation. A rocker sole may be added as well to facilitate transition from foot flat to the toe-off phase of gait. Proper shoe fit is important, but “snug” fitting shoes in a patient with peripheral neuropathy and likely fluctuations in volume from intermittent swelling are to be avoided. A custom shoe is an unnecessary expense. The patient has at least 10 degrees of dorsiflexion at the ankle with an intact anterior tibialis muscle; therefore, catching the sole on carpeting should not be a problem.
REFERENCES: Philbin TM, Leyes M, Sferra JJ, et al: Orthotic and prosthetic devices in partial foot amputations. Foot Ankle Clin 2001;6:215-228.
Pinzur MS, Dart HC: Pedorthic management of the diabetic foot. Foot Ankle Clin 2001;6:205-214.

Question 97

Genetic mutations that may result in the cervical abnormalities noted in the figures generally affect the

Explanation

DISCUSSION
The figures are characteristic of a child with Klippel-Feil syndrome (congenital cervical spine abnormalities) in association with congenital scoliosis in the upper thoracic spine and a right-sided Sprengel deformity (congenital elevation of the scapula). Sprengel deformity occurs in as many as 30% of children with Klippel-Feil syndrome. Other congenital conditions that are commonly associated with Klippel-Feil, and that should be screened for, include deafness in 30%, genitourinary abnormalities in 25% to 35%, and cardiovascular abnormalities in 4% to 29% of children with Klippel-Feil syndrome.
In Sprengel deformity, there is usually a tether called the omovertebral connection between the abnormally elevated scapula and the spinous processes in the upper thoracic region. This tether is most commonly bony but also may be cartilaginous or fibrous. Although there also may be abnormalities in the ribs, clavicle, or humerus, they are morphologic abnormalities only, not tethers.
Patients with Klippel-Feil syndrome should be discouraged from participating in contact or collision sports if they have a massive fusion of the cervical spine, any involvement of C2, or limited cervical motion. Fusions at 1 or 2 interspaces below C3 and normal cervical motion do not preclude participation in activities. A Sprengel deformity may limit abduction of the shoulder and normal racquet or throwing mechanics, but, in the absence of pain, is not a contraindication to attempted participation.
Klippel-Feil syndrome affects a heterogenous cohort of patients and different inheritance patterns have been seen, including autosomal-dominant and autosomal-recessive types, with varying levels of penetrance. The first human Klippel-Feil syndrome locus was identified on chromosome 8 and is called SGM1. Other candidates for mutations in Klippel-Feil include PAX genes and Notch pathway genes. In general, the involved genes help regulate the formation and segmentation of the vertebrae.
Between days 20 and 30 following conception, the paraxial mesoderm subdivides into segments called somites. As they mature, somites develop into 3 layers called the sclerotome, myotome, and dermatome. The sclerotome undergoes a process of resegmentation during which the caudal section from 1 somite joins with the rostral section of the immediately caudal somite to form the vertebral bodies. It is during the processes of segmentation and resegmentation that the abnormalities leading to Klippel-Feil syndrome occur. Gastrulation refers to the phase early in embryonic development when the single-layered blastula is reorganized into a trilaminar structure with 3 germ layers: the ectoderm, mesoderm, and endoderm. Neurulation refers to the process by which the notochord induces formation of the neural tube from the neural plate, forming the brain and spinal cord.

Question 98

Which of the following procedures is included in third-generation cement technique?

Explanation

DISCUSSION: The so-called third-generation cement technique adds porosity reduction techniques, centralization devices, and surface modifications to the femoral component. The surgeon must be aware of the meaning of the various generations of cement technique when interpreting the results presented at meetings and in the literature.
REFERENCES: Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 181-193.
Maloney WJ, Hartford JM: The cemented femoral component, in Callaghan JJ, Rosenberg AG, Rubash HE (eds): The Adult Hip. Philadelphia, PA, Lippincott-Raven, 1998, vol 2, pp 959-979.

Question 99

The diagnostic distinction between a benign enchondroma and a low- grade intramedually chondrosarcoma is based primarily on the

Explanation

"The diagnostic strategies for benign bone tumors center on the initial radiographic presentation." … "For example calcified, lytic phylangeal lesion strongly suggests the presence of cartilage that is consistent with enchondroma."

Question 100

What is the most appropriate next step in the work-up of a patient with the asymptomatic lesion shown in Figure 23?

Explanation

DISCUSSION: The eccentric metaphyseal location, skeletal maturity, narrow zone of transition, and lack of symptoms suggest a benign process and are consistent with a healed nonossifying fibroma. These lesions typically fill in (ossify) with skeletal maturity, eventually remodeling and disappearing. Radiographic monitoring is indicated. Biopsy is not recommended unless the lesion changes radiographically.
REFERENCES: Marks KE, Bauer TW: Fibrous tumors of bone. Orthop Clin North Am 1989;20:377-393.
Bullough PG, Walley J: Fibrous cortical defect and non-ossifying fibroma. Postgrad Med J 1965;41:672-676.
Skrede O: Non-osteogenic fibroma of bone. Acta Orthop Scand 1970;41:362-380.

Full Question & Answer Text (for Search Engines)

Question 1:

The direct anterior (Smith-Peterson) approach to hip arthroplasty is most commonly associated with injury to what nerve?

Options:

Lateral femoral cutaneous
Sciatic
Pudendal
Superior gluteal

Correct Answer: Lateral femoral cutaneous

Explanation:

Question 2:

Figures 71a and 71b/ are the MR images of a 65-year-old man who dislocated his shoulder. What is his most likely chief symptom?

Options:

Numbness in the anterior aspect of his shoulder
Recurrent instability
Difficulty raising his arm
Biceps muscle deformity

Correct Answer: Difficulty raising his arm

Explanation:

DISCUSSION
This patient has a massive rotator cuff tear resulting in disruption of the transverse force couple between the subscapularis anteriorly and the infraspinatus and teres minor posteriorly. These muscles provide dynamic shoulder stability throughout active elevation. Loss of the force couple produces a pathologic increase in translation of the humeral head and decreased active abduction and external rotation, which results in difficulty raising an arm. The most common neurologic deficit after shoulder dislocation is isolated injury to the axillary nerve that supplies sensation to the lateral aspect of the shoulder, not the anterior aspect. Recurrent instability is uncommon unless there is a labral tear or massive subscapularis tear. The biceps muscle is not viewed in the MR images, and a complete proximal biceps tendon rupture would be uncommon in the setting of an anterior shoulder dislocation.
CLINICAL SITUATION FOR QUESTIONS 72 THROUGH 75
Figures 72a through 72e are the MR images of a 12-year-old boy with left lateral-sided knee pain following a football injury. He has a several-year history of recurrent knee pain that improves with rest. An examination reveals a moderate effusion. Range of motion is 0 degrees
to 90 degrees and is limited by pain in deep flexion. He has tenderness to palpation along the lateral joint line, and no instability is noted.

Question 3:

Options:

Cemented left total hip arthroplasty (THA)
Cementless left THA with a proximally porous coated femoral stem
Hybrid left THA
Cementless left THA with a diaphyseal engaging conical femoral stem

Correct Answer: Hybrid left THA

Explanation:

Question 4:

Options:

Surgical reconstruction
Rest, followed by physical therapy
Splinting in 15 degrees of flexion
Primary repair
Arthroscopic debridement, followed by bracing in full extension for 4 weeks

Correct Answer: Surgical reconstruction

Explanation:

Question 5:

Options:

(X; 18) (p11; q11)
(11; 22) (q24; q12)
(12; 22) (q13; q12)
(2; 13) (q35; q14)
(12; 16) (q13; p11)

Correct Answer: (X; 18) (p11; q11)

Explanation:

DISCUSSION: This is a case of synovial sarcoma. The radiograph shows some soft-tissue swelling in the upper arm. The MRI scans show a lesion that has increased signal on T
2
-weighted images and low signal on T
1
-weighted images. There is a suggestion of a large cystic component to this lesion. The pathology shows a biphasic population of cells, a spindle cell component, and an epithelioid component. Up to 20% of synovial cell sarcomas have areas of cyst formation. The most common cytogenetic translocation with synovial cell sarcoma is X; 18. The 11; 22 translocation is most commonly associated with Ewing’s sarcomas; the 12; 22 translocation is most commonly associated with clear cell sarcomas; the 2; 13 translocation is most commonly associated with alveolar rhabdomyosarcomas, and the 12; 16 translocation is most commonly associated with myxoid liposarcomas.
REFERENCES: Kawai A, Woodruff J, Healey JH, et al: SYT-SSX gene fusion as a determinant of morphology and prognosis in synovial sarcoma. New Engl J Med 1998;338:153-160.
Sandberg AA: Cytogenetics and molecular genetics of bone and soft tissue tumors. Am J Med Genet 2002;115:189-193.

Question 6:

Options:

Deep-wound infection.
Aseptic loosening
Osteoporosis
Initial implant stability

Correct Answer: Initial implant stability

Explanation:

DISCUSSION
The image demonstrates subsidence of the femoral implant. The implant subsided because it did not have good initial stability. The tapered femoral implant was placed after initial preparation for an anatomic femoral stem. A limited, nondisplaced femoral neck fracture was encountered during the procedure and treated. Two advantages of tapered stems are the efficient transfer of stress to the proximal femur and the ability to accommodate some subsidence to achieve enhanced stability. Although subsidence of a tapered stem to a more stable position can produce a good result, quality of metaphyseal bone should be considered. Attention to surgical technique remains important to optimize component stability for biological fixation.
RECOMMENDED READINGS
Savory CG, Hamilton WG, Engh CA Sr, Della Valle CJ, Rosenberg AG, Galante JO.
15
Hip designs. In: Barrack RL, Booth RE Jr, Lonner JH, McCarthy JC, Mont MA, Rubash HE, eds. Orthopaedic Knowledge Update: Hip and Knee Reconstruction 3.
Rosemont, IL: American Academy of Orthopaedic Surgeons; 2006:345-368.
Blaha JD, Borus TA. Press-fit femoral components. In: Callaghan J, Rosenberg A, and Rubash H, eds The Adult Hip. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2007:1036-1043.

Question 7:

Which of the following has been shown to have similar biochemical and clinical characteristics as iliac crest autograft?

Options:

BMP-2
BMP-7 with collagen matrix carrier
Hydroxyapatite cement
Platelet rich plasma with allograft cancellous bone carrier
Femoral intramedullary reaming contents

Correct Answer: BMP-2

Explanation:

Question 8:

Options:

Central slip tenotomy
Terminal tendon release
Dorsal rerouting of the lateral bands
Intrinsic lengthening

Correct Answer: Central slip tenotomy

Explanation:

Question 9:

Options:

Localized pigmented villonodular synovitis (PVNS)
Biphasic synovial sarcoma
Nodular fasciitis
Synovial hemangioma DISCUSSION.. The incidental finding in the posterior intercondylar notch of the knee in this patient represents a benign synovial hemangioma. No intralesional calcifications are shown either on the plain radiographs or CT scan. The MRI scans reveal a hypervascular lesion with multiple filling defects, with hyperintensity on T2-weighted images and low to intermediate signal intensity on T1-weighted images. Histologically, vascular lakes within fine capillaries with a synovium on the surface of the lesion are characteristic of this condition. Many patients with synovial hemangioma present with pain, swelling, stiffness, or mechanical symptoms. As with PVNS, the disease can be localized or diffuse in nature. Surgical excision, either open or arthroscopic, is the recommended treatment. PVNS is the most common intra-articular tumor, but hypointensity in either the diffuse or localized type is characteristic on MRI scan in both T1- and T2-weighted images. Synovial sarcoma, although often found close to a joint, is not characteristically found within a joint. Nodular fasciitis is not found in intra-articular locations.

Correct Answer: Synovial hemangioma DISCUSSION.. The incidental finding in the posterior intercondylar notch of the knee in this patient represents a benign synovial hemangioma. No intralesional calcifications are shown either on the plain radiographs or CT scan. The MRI scans reveal a hypervascular lesion with multiple filling defects, with hyperintensity on T2-weighted images and low to intermediate signal intensity on T1-weighted images. Histologically, vascular lakes within fine capillaries with a synovium on the surface of the lesion are characteristic of this condition. Many patients with synovial hemangioma present with pain, swelling, stiffness, or mechanical symptoms. As with PVNS, the disease can be localized or diffuse in nature. Surgical excision, either open or arthroscopic, is the recommended treatment. PVNS is the most common intra-articular tumor, but hypointensity in either the diffuse or localized type is characteristic on MRI scan in both T1- and T2-weighted images. Synovial sarcoma, although often found close to a joint, is not characteristically found within a joint. Nodular fasciitis is not found in intra-articular locations.

Explanation:

Question 10:

An 8-year-old boy falls and injures his thumb. A radiograph is shown in Figure 23. Initial management should consist of

Options:

closed reduction.
closed reduction and percutaneous pinning.
open reduction through a volar approach.
open reduction through a dorsal approach.
splinting for comfort.

Correct Answer: closed reduction.

Explanation:

Question 11:

Compared with myodesis, osteomyoplasty offers which of the following advantages in transtibial amputation?

Options:

Enhanced end-bearing
Early prosthetic fitting
Immediate weight bearing
Fibular abduction
Decreased surgical morbidity

Correct Answer: Enhanced end-bearing

Explanation:

Question 12:

Which of the following radiographic findings indicates that the injury to the great toe shown in Figures 60a and 60b should be reducible by closed manipulation?

Options:

The sesamoids are separated
The sesamoid is fractured
The proximal phx is on the neck of the metatarsal
The dislocation is dorsal and centered
The proximal phalanx is hyperextended

Correct Answer: The sesamoids are separated

Explanation:

Question 13:

Options:

anterior diskectomy and fusion at C4-C5.
immobilization in a Philadelphia collar and voluntary flexion and extension radiographs when awake.
occipital-cervical fusion with instrumentation.
halo immobilization for 12 weeks.
left C6 superior facetectomy and posterior fusion at C6-C7 with instrumentation.

Correct Answer: occipital-cervical fusion with instrumentation.

Explanation:

DISCUSSION: The CT scans reveal an occipital-cervical dissociation with subluxation of the occipitocervical joints bilaterally. Definitive management should consist of an occipital-cervical fusion with instrumentation. Immobilization in a Philadelphia collar is inadequate for this highly unstable injury, and halo immobilization, while affording adequate temporary immobilization, is not appropriate definitive management for this ligamentous injury. The patient does not have an injury at C4-C5 or C6-C7.
REFERENCES: Jackson RS, Banit DM, Rhyne AL III, et al: Upper cervical spine injuries.
J Am Acad Orthop Surg 2002;10:271-280.
Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 201-216.

Question 14:

Options:

debridement and locked intermedullary nailing.
debridement and plate fixation.
debridement and external fixation.
debridement and traction.
skeletal traction.

Correct Answer: debridement and external fixation.

Explanation:

Question 15:

What is the most common causative bacteria in septic arthritis in children? Review Topic

Options:

Staphylococcus aureus
Brucella melitensis
Haemophilus influenzae
Kingella kingae
Streptococcus pneumonia

Correct Answer: Staphylococcus aureus

Explanation:

Question 16:

Figure 36 shows the hip arthrogram of a newborn. Which of the following structures is enclosed by the circle?

Options:

Limbus
Pulvinar
Ligamentum teres
Transverse acetabular ligament
Acetabular labrum

Correct Answer: Acetabular labrum

Explanation:

DISCUSSION: The structure enclosed by the circle is the acetabular labrum. It is visible as the white point of tissue outlined by the darkly radiopaque contrast. The appearance of the contrast surrounding the sharp white point of a normal labrum is called the “rose thorn sign.” The limbus is the term reserved for a rounded, infolded labrum seen with arthrography. The pulvinar is the fatty tissue seen in the empty acetabulum when the hip is dislocated. The ligamentum teres is seen as a white stripe outlined by contrast coursing from the central acetabulum to the dislocated femoral head. The transverse acetabular ligament courses across the inferior portion of the acetabulum and is not clearly seen with arthrography.
REFERENCES: Herring JA: Tachdjian’s Pediatric Orthopaedics, ed 3. Philadelphia, PA,
WB Saunders, 2002, vol 1, pp 532-533.
Severin E: Contribution to the knowledge of congenital dislocation of the hip joint.
Acta Chir Scand 1941;84:1.

Question 17:

Options:

Physical therapy with emphasis on neck muscle strengthening and posture improvement
Epidural steroid injection
Anterior cervical discectomy and fusion
Laminectomy alone
Multi-level laminectomy and fusion

Correct Answer: Physical therapy with emphasis on neck muscle strengthening and posture improvement

Explanation:

Question 18:

Options:

Splinting, admission, and frequent neurovascular checks
Cylinder cast and discharge
Four-compartment calf fasciotomy
Non-weight-bearing, a knee immobilizer, and follow- up in 1 week

Correct Answer: Splinting, admission, and frequent neurovascular checks

Explanation:

Question 19:

What neurovascular structure is in closest proximity to the probe in the arthroscopic view of the elbow shown in Figure 50? Review Topic

Options:

Ulnar nerve
Radial nerve
Posterior interosseous nerve
Superficial radial nerve
Median nerve

Correct Answer: Radial nerve

Explanation:

Question 20:

Options:

Decreased sensation on the dorsum of his foot involving the hallux, 3rd, and 4th toes
Inability to plantar flex the ankle
Decreased sensation on the dorsum of his foot involving the first webspace
Inability to dorsiflex the ankle
Inability to abduct his toes

Correct Answer: Decreased sensation on the dorsum of his foot involving the hallux, 3rd, and 4th toes

Explanation:

Question 21:

A concussion diagnosis is made when there is

Options:

a 20% decrease in the neurocognitive score from baseline.
a brain MRI with abnormal findings.
a loss of consciousness for longer than 15 seconds.
evidence of a traumatic brain injury that alters the way the brain functions.

Correct Answer: evidence of a traumatic brain injury that alters the way the brain functions.

Explanation:

Question 22:

Options:

higher infection rates.
higher nonunion rates.
equal union and infection rates.
higher rate of ARDS.
higher mortality rate.

Correct Answer: equal union and infection rates.

Explanation:

DISCUSSION: Recently Harwood and associates investigated the principles of damage control orthopaedics (DCO) as they apply to patients with femoral shaft fractures. When they compared those who underwent initial external fixation of femoral shaft fractures with conversion to an intramedullary nail to those who underwent intramedullary nailing as their initial treatment, they found the following: overall infection rates were comparable in patients receiving DCO versus primary intramedullary fixation; open fracture was an independent risk factor for infection regardless of the treatment method; contamination rates in external fixator pin sites rose considerably when left in place more than 2 weeks and logistic regression analysis suggests that infection rates may increase when conversion to an intramedullary nail occurs after 2 weeks following external fixation; and there was no significant difference in time to union among treatment groups.
REFERENCES: Harwood PJ, Giannoudis PV, Probst C, et al: The risk of local infective complications after damage control procedures for femoral shaft fracture. J Orthop Trauma 2006;20:181-189.
Roberts CS, Pape HC, Jones AL, et al: Damage control orthopaedics: Evolving concepts in the treatment of patients who have sustained orthopaedic trauma. Instr Course Lect
2005;54:447-462.

Question 23:

Options:

Central band ligament
Accessory band ligament
Annular ligament
Dorsal oblique accessory cord ligament
Distal oblique bundle ligament

Correct Answer: Central band ligament

Explanation:

Question 24:

Figure 12 shows a lateral radiograph of the elbow. What is the most likely diagnosis?

Options:

Osteochondroma
Old fracture fragment
Heterotopic ossification
Normal anatomic variant
Osteosarcoma

Correct Answer: Normal anatomic variant

Explanation:

Question 25:

Options:

There is no significant difference in operative time when using cemented stems compared with uncemented stems
Comparing HA to THA, there is no difference in blood loss
Longer term outcomes are better with HA
Bipolar HA performed through a direct anterior or lateral approach leads to equivalent patient outcomes as THA
Perioperative complication rate is greater after THA than bipolar HA

Correct Answer: Comparing HA to THA, there is no difference in blood loss

Explanation:

Question 26:

Options:

cessation of throwing activities.
a long arm cast for 3 months.
a corticosteroid injection into the elbow joint.
excision of the fragment.
arthroscopic drilling of the lesion.

Correct Answer: cessation of throwing activities.

Explanation:

DISCUSSION: The radiograph shows osteochondritis dissecans (OCD) of the capitellum, one manifestation of “pitcher’s elbow.” The lesion is nondisplaced, and healing is possible if the inciting throwing activities are curtailed. Long arm cast treatment may be reasonable for the noncompliant patient but should not exceed 6 weeks duration. Surgical treatment is indicated for loose bodies or cartilage flaps. Elbow OCD lesions are now being seen in younger children as more participate in organized sports, especially baseball and gymnastics.
REFERENCES: Bauer M, Jonsson K, Josefsson PO, et al: Osteochondritis dissecans of the elbow: A long-term follow-up study. Clin Orthop 1992;284:156-160.
Takahara M, Ogino T, Sasaki I, et al: Long term outcome of osteochondritis dissecans of the humeral capitellum. Clin Orthop 1999;363:108-115.
Byrd JW, Jones KS: Arthroscopic surgery for isolated capitellar osteochondritis dissecans in adolescent baseball players: Minimum three-year follow-up. Am J Sports Med
2002;30:474-478.

Question 27:

Options:

an internervous plane between muscles innervated by the deep and superficial peroneal nerves.
an internervous plane between muscles innervated by the deep peroneal and the medial plantar nerves.
an interval between the extensor digitorum longus and the extensor digitorum brevis.
not an internervous plane.

Correct Answer: not an internervous plane.

Explanation:

Question 28:

Options:

Admission and traction
Open surgical debridement of the lesion
Perform an open biopsy of the lesion
Nonsurgical treatment with antibiotics and immobilization DISCUSSION -Childhood diskitis represents one end of a continuum of spinal infections, from diskitis to vertebral osteomyelitis with soft-tissue abscess. Diskitis is now generally accepted as a bacterial infection involving the disk space and adjacent vertebral end plates. Optimal treatment includes the use of antibiotics. Empiric coverage is directed against Staphylococcus aureus because it has been the most common organism isolated from culture-positive biopsy specimens. Open biopsy is not necessary for patients who exhibit all of these clinical characteristics, but it is indicated for those whose symptoms do not resolve rapidly with treatment or who have atypical presentation.

Correct Answer: Nonsurgical treatment with antibiotics and immobilization DISCUSSION -Childhood diskitis represents one end of a continuum of spinal infections, from diskitis to vertebral osteomyelitis with soft-tissue abscess. Diskitis is now generally accepted as a bacterial infection involving the disk space and adjacent vertebral end plates. Optimal treatment includes the use of antibiotics. Empiric coverage is directed against Staphylococcus aureus because it has been the most common organism isolated from culture-positive biopsy specimens. Open biopsy is not necessary for patients who exhibit all of these clinical characteristics, but it is indicated for those whose symptoms do not resolve rapidly with treatment or who have atypical presentation.

Question 29:

Options:

The serum ion levels are not measureable in these patients.
The serum ion levels are measureable, but are of negligible value in these patients.
The serum ion levels measured equal the values measured in the local tissues in total hip arthroplasty metal-on-metal prostheses.
The serum ion levels measured are much lower in terms of their level to the values measured in total hip arthroplasty metal-on-metal prostheses.
The serum ion levels measured are similar in terms of their level to the values measured in total hip arthroplasty metal-on-metal prostheses.

Correct Answer: The serum ion levels measured are similar in terms of their level to the values measured in total hip arthroplasty metal-on-metal prostheses.

Explanation:

Question 30:

Options:

IV antibiotics.
arthroscopic irrigation and debridement, following by IV antibiotics.
irrigation and debridement, polyethylene exchange, and IV antibiotics.
one-stage component removal and reimplantation, followed by IV antibiotics.
two-stage component removal and reimplantation, with IV antibiotics in the interim period.

Correct Answer: irrigation and debridement, polyethylene exchange, and IV antibiotics.

Explanation:

Question 31:

Which of the following acetabular cup designs has shown the greatest survivorship at 10 years in patients younger than age 60 years?

Options:

Cemented polyethylene socket
Cemented metal-backed socket
Cementless hydroxyapatite-coated smooth metal-backed socket
Cementless threaded metal-backed socket
Cementless porous-coated metal-backed socket

Correct Answer: Cementless porous-coated metal-backed socket

Explanation:

Question 32:

Options:

parental abuse.
abnormal osteoclast function.
defective N-Ac-Gal-6 sulfate sulfatase enzyme.
a quantitative defect of type I collagen synthesis.
vitamin D deficiency.

Correct Answer: a quantitative defect of type I collagen synthesis.

Explanation:

Question 33:

Options:

Shoulder abduction
Shoulder external rotation
Shoulder internal rotation
Elbow extension
Forearm supination

Correct Answer: Forearm supination

Explanation:

Question 34:

Options:

Bisphosphonates
Calcitonin
Parathyroid hormone
Vitamin D and calcium
Methotrexate

Correct Answer: Bisphosphonates

Explanation:

Question 35:

A 22-year-old woman injured her ankle when she fell off a ladder. Radiographs reveal a displaced large posterior malleolus fracture of about 45% of the joint. What is the best definitive treatment?

Options:

Open reduction and internal fixation with absolute stability
Open reduction and internal fixation with relative stability
Closed reduction with casting
Reamed locked intramedullary nailing
External fixation

Correct Answer: Open reduction and internal fixation with absolute stability

Explanation:

Basic understanding of fracture care requires a fundamental knowledge of the principles regarding absolute and relative stability. Compression plating and anatomic reduction of articular fractures are examples of absolute stability. Bridge plating, external fixation, casting, and intramedullary nailing are all examples of relative stability. Both bone forearm fractures have long been treated with open reduction and internal fixation even in the light of open wounds. Results have been excellent with plate fixation. Recently, intramedullary nails that are contoured and locked have been used in the treatment of both bone forearm fractures, but they are not reamed. It is well established that with restoring the proper radial bow, length, and alignment,
optimal function can be achieved. Open reduction and internal fixation allows this achievement. In cases where comminution exists, absolute stability may have to be sacrificed so as to not strip small comminuted bone fragments. Therefore, a bridging technique is worthwhile. External fixation can be used as a temporary technique until the soft tissues are more amenable to definitive fixation. Cast treatment is not indicated in adult forearm fractures. Locking nails for forearm use are not reamed. With regards to articular fractures, anatomic reduction and rigid stabilization are required to achieve the best results and allow for fracture healing. This environment also allows for the best chance of the cartilage repair process to form "hyaline-like" cartilage. Open reduction and internal fixation with absolute stability is the mainstay of treatment for partial articular fractures such as split depression tibial plateau fractures and posterior malleolus fractures involving greater than about 25% to 30% of the joint. The gold standard for the treatment of a closed femur fracture is a reamed intramedullary locked nail. Results are uniformly excellent. This can be done without stripping of the soft tissues such as in open reduction and internal fixation. External fixation can be used as a temporary device in patients in extremis for damage control reasons.Moed BR, Kellam JF, Foster RJ, Tile M, Hansen ST Jr. Immediate internal fixation of open fractures of the diaphysis of the forearm. J Bone Joint Surg Am. 1986 Sep;68(7):1008-17.
http://www.ncbi.nlm.nih.gov/pubmed/3745238')">View Abstract at PubMedJones DB Jr, Kakar S. Adult diaphyseal forearm fractures: intramedullary nail versus plate fixation. J Hand Surg Am. 2011 Jul;36(7):1216-9. Epub 2011 May

Question 36:

Options:

Posterior laminoplasty
Posterior cervical foraminotomy
Anterior cervical foraminotomy
Anterior cervical diskectomy and arthrodesis
Anterior corpectomy and arthrodesis

Correct Answer: Anterior cervical diskectomy and arthrodesis

Explanation:

Question 37:

Options:

Popliteal artery
Popliteal vein
Tibial nerve
Popliteus muscle
Soleus muscle

Correct Answer: Popliteus muscle

Explanation:

DISCUSSION: The major risk of performing a high tibial osteotomy is neurovascular injury. The new version of the high tibial osteotomy makes a transverse osteotomy at the level of the tibial tubercle. The osteotome is protected by the oblique belly of the popliteus muscle. The popliteal artery and vein and tibial nerve all lie posterior to the muscle. The soleus muscle originates below this level.
REFERENCES: Clement CD: Anatomy: A Regional Atlas of Human Anatomy, ed 3.
Baltimore, MD, Munich, Germany, Urban and Schwarzberg, 1987, Figure 422.
Netter FH: Atlas of Human Anatomy. Summit, NJ, Ciba-Geigy, 1989, plate 480.

Question 38:

Options:

Application of a compressive dressing and boot brace and monitoring of compartment pressures
Administration of IV antibiotics and strict elevation
Oral antibiotics, elevation, and close follow-up
Debridement of the bullae and application of a new cast
Urgent surgical debridement and IV antibiotics

Correct Answer: Urgent surgical debridement and IV antibiotics

Explanation:

Question 39:

A 40-year-old man sustains a scapular body fracture after an all-terrain vehicle accident. Which of the following is the most commonly associated injury?

Options:

Chest injury
Clavicle fracture
Glenohumeral dislocation
Humeral fracture
Axillary nerve injury

Correct Answer: Chest injury

Explanation:

Question 40:

Sacral fractures are most likely to be associated with neurologic deficits when they involve what portion of the sacrum?

Options:

Zone 1 (the ala)
Zone 2 (the foramina)
Zone 3 (the central canal)
Zones 1 and 2
The sacral laminae

Correct Answer: Zone 3 (the central canal)

Explanation:

DISCUSSION: Denis divided the sacrum into three zones: zone 1 represents the lateral ala, zone 2 represents the foramina, and zone 3 represents the central canal. A fracture is classified according to its most medial extension. Those in zone 3 are typically bursting-type fractures or fracture-dislocations and are most prone to neurologic sequelae.
REFERENCES: Denis F, Davis S, Comfort T: Sacral fractures: An important problem.
A retrospective analysis of 236 cases. Clin Orthop Relat Res 1988;227:67-81.
Wood KB, Denis F: Fractures of the sacrum and coccyx, in Vacarro AR (ed): Fractures of the Cervical, Thoracic and Lumbar Spine. New York, NY, Marcel Dekker, 2003, pp 473-488.

Question 41:

Options:

Increase risk for iatrogenic ulnar nerve injury
Provide more construct stiffness than adding a medial pin
Improve construct stiffness in the presence of medial column comminution
Will not affect construct stiffness in the presence of residual distal fragment internal rotation

Correct Answer: Improve construct stiffness in the presence of medial column comminution

Explanation:

Question 42:

Options:

Immobilization
Rest with range-of-motion exercises
Steroid injection
Excision
Irradiation

Correct Answer: Rest with range-of-motion exercises

Explanation:

Question 43:

Options:

closed reduction and cast immobilization for 6 weeks.
closed reduction and percutaneous pin fixation.
open reduction of the tarsal navicular and closed management of the Lisfranc joint.
open reduction and internal fixation of the Lisfranc joint, the tarsal navicula, and second metatarsal neck fractures.
open reduction and primary arthrodesis of the Lisfranc joint and internal fixation of the tarsal navicula and second metatarsal neck fractures.

Correct Answer: open reduction and internal fixation of the Lisfranc joint, the tarsal navicula, and second metatarsal neck fractures.

Explanation:

Question 44:

Options:

increased strength of the rotator cuff repair by creating thicker repair construct.
decreased size of the defect exposing the humeral head.
decreased stress in the rotator cuff at the site of the side-to-side repair.
decreased stress in the rotator cuff at the free margin and greater tuberosity interface.
decreased stress in the rotator cuff crescent cable.

Correct Answer: decreased stress in the rotator cuff at the free margin and greater tuberosity interface.

Explanation:

Question 45:

Collagen orientation is parallel to the joint surface in what articular cartilage zone?

Options:

Diagonal
Middle
Deep
Superficial
Calcified

Correct Answer: Superficial

Explanation:

Question 46:

Options:

irrigation and debridement.
single-stage exchange.
stage exchange.
observation.

Correct Answer: observation.

Explanation:

Question 47:

Figure 11 shows the radiograph of an otherwise healthy 22-year-old man who sustained a midfoot injury in a motor vehicle accident 9 days ago. Treatment should consist of

Options:

open reduction and internal fixation.
a short leg weight-bearing cast.
a short leg non-weight-bearing cast.
first tarsometatarsal fusion.
functional brace application and early range of motion.

Correct Answer: open reduction and internal fixation.

Explanation:

DISCUSSION: The dislocation is between the medial and middle cuneiform. Although the first and second tarsometatarsal joints are aligned, there is a gap between the cuneiforms. The radiograph shows a Lisfranc dislocation variant. In a healthy active individual, open reduction and internal fixation yields the best results. The reestablishment of the normal arch and medial column support with anatomic reduction is critical to obtaining the best possible outcome from these injuries.
REFERENCES: Teng AL, Pinzur MS, Lomasney L, et al: Functional outcome following anatomic restoration of the tarsal-metatarsal fracture dislocation. Foot Ankle Int
2002;23:922-926.
Kuo RS, Tejwani NC, DiGiovanni CW, et al: Outcome after open reduction and internal fixation of Lisfranc joint injuries. J Bone Joint Surg Am 2000;82:1609-1618.

Question 48:

What ligament is the primary restraint to applied valgus loading of the knee?

Options:

Posteromedial capsule
Posterior cruciate ligament (PCL)
Superficial medial collateral ligament (MCL)
Deep MCL
Medial meniscus

Correct Answer: Superficial medial collateral ligament (MCL)

Explanation:

Question 49:

Figure 8 shows the radiograph of a 76-year-old man who has knee pain and swelling. History reveals that he underwent total knee arthroplasty 18 years ago. What is the most likely diagnosis?

Options:

Loose femoral component
Loose tibial component
Particle-mediated osteolysis
Polyethylene failure
Infection

Correct Answer: Polyethylene failure

Explanation:

DISCUSSION: The radiograph reveals complete loss of joint space with particulate metal debris consistent with total polyethylene failure and metal-on-metal articulation. The components appear to be well fixed and minimal osteolysis is evident.
REFERENCES: Kilgus DJ, Moreland JR, Finerman GA, et al: Catastrophic wear of tibial polyethylene inserts. Clin Orthop Relat Res 1991;273:223-231.
Vince KG: Why knees fail. J Arthroplasty 2003;18:39-44.

Question 50:

Options:

Lymphoma
Malignant fibrous histiocytoma
Synovial sarcoma
Fibromatosis
Elastofibroma

Correct Answer: Elastofibroma

Explanation:

DISCUSSION: Elastofibroma is a rare, benign soft-tissue pseudotumor characteristically located in the subscapular region. Most patients are between 50 and 70 years of age and have pain, decreased shoulder range of motion, or a mass. The lesion usually is best visualized with the arm elevated forward and adducted to displace the scapula laterally and allow the mass to protrude from the chest wall. They are frequently bilateral. Grossly, the mass is ill-defined, oblong or spherical, firm, and ranges in size from 5 cm to 10 cm. These masses appear infiltrative and frequently are mistaken for a sarcomatous lesion. Histologically, the mass is composed of a mixture of intertwining eosinophilic collagen and elastic fibers, and scattered fibroblasts, mucoid material, and fat.
REFERENCES: Vastamaki M: Elastofibroma scapulae. Clin Orthop Relat Res 2001;392:404-408.
Nielsen T, Sneppen O, Mykre-Jensen O, et al: Subscapular elastofribroma: A reactive pseudotumor. J Shoulder Elbow Surg 1996;5:209-213.
Weiss SW, Goldblum JR, Enzinger FM: Enzinger and Weiss’s Soft Tissue Tumors, ed 4.
Philadelphia, PA, Elsevier, 2001, pp 286-289.

Question 51:

- What is the usual mechanism of injury for the fracture shown in Figures 49a and 49b?

Options:

bending
axial loading
high-speed rotation
direct impact from anteromedial
crush from anteromedial to posterolateral

Correct Answer: axial loading

Explanation:

Question 52:

Options:

Will result in improvement in pain but no difference in function or range of motion compared to therapy alone.
Will result in greater improvement in pain and function compared to therapy alone, with equivalent range of motion at one year
Will prevent development of rotator cuff arthropathy in patients with rotator cuff tears.
Will likely have no effect on pain, function or range of motion at one year, compared to therapy alone.
Will result in worse outcomes in terms of pain, function and range of motion, compared with therapy alone.

Correct Answer: Will result in worse outcomes in terms of pain, function and range of motion, compared with therapy alone.

Explanation:

Question 53:

Options:

Tibial nerve injury
Associated ankle fracture
Acute compartment syndrome
Injury to the common peroneal nerve
Rupture of the tibialis anterior tendon

Correct Answer: Injury to the common peroneal nerve

Explanation:

Question 54:

Which of the following post-reduction forearm fractures patterns may be treated non-operatively in an otherwise healthy 22-year old male?

Options:

Displaced diaphyseal fracture of the radius
Non-displaced diaphyseal fracture of the radius, displaced diaphyseal fracture of the ulna
Displaced diaphyseal fractures of both bones of the forearm, with less than 10 degrees angulation after closed reduction
An isolated mid-shaft ulna fracture translated 20%, with less than 5 degrees of angulation
Gustilo grade II open fracture of the radius

Correct Answer: Displaced diaphyseal fracture of the radius

Explanation:

Question 55:

What does Dual Energy X-ray Absorptiometry (DEXA) testing, as a technique, measure?

Options:

Qualitative value of core bone mineral content
Differentiation of trabecular and cortical bone content
Core bone mineral density unchanged by osteoarthritis at or around the site
Bone mineral content and soft-tissue composition
Bone mineral content and density without need for cross-sectional dimension

Correct Answer: Bone mineral content and soft-tissue composition

Explanation:

Question 56:

What structure is considered the single most important soft-tissue restraint to anterior-posterior stability of the sternoclavicular joint?

Options:

Posterior capsular ligament
Anterior capsular ligament
Interclavicular ligament
Intra-articular disk
Subclavius tendon

Correct Answer: Posterior capsular ligament

Explanation:

Question 57:

Options:

Ultrasound bladder to exclude bladder perforation
CT abdomen to exclude bowel perforation
MRI pelvis to exclude genital injuries
CT angiogram exclude laceration of major vessels
CT acetabulum to exclude intra-articular foreign body

Correct Answer: CT acetabulum to exclude intra-articular foreign body

Explanation:

Question 58:

Options:

Radiation therapy alone
Intralesional steroid injection
Chemotherapy followed by surgery or radiation therapy
Debridement and antibiotics
Debridement alone

Correct Answer: Debridement and antibiotics

Explanation:

DISCUSSION: The clinical presentation of this patient is consistent with both acute osteomyelitis and Ewing’s sarcoma. Both entities can be noted in the distal femoral metaphysis although Ewing’s sarcoma is classically noted in the diaphysis. The histology reveals a mixed inflammatory cell infiltrate with neutrophils, plasma cells, lymphocytes, and histiocytes. Ewing’s sarcoma would be a uniform population of small round blue cells without an inflammatory component. Eosinophilic granuloma (EG) is characterized by Langerhans histiocytes and eosinophils. Treatment of EG often consists of an intralesional steroid injection. Treatment of acute osteomyelitis includes surgical debridement and antibiotics.
REFERENCES: McCarthy JJ, Dormans JP, Kozin SH, et al: Musculoskeletal infections in children: Basic treatment principles and recent advancements. Instr Course Lect 2005;54:515-528.
Calhoun JH, Manring MM: Adult osteomyelitis. Infect Dis Clin North Am 2005;19:765-786.

Question 59:

Options:

arthroscopic debridement of the articular lesion and resurfacing.
knee aspiration and an intra-articular cortisone injection.
rheumatologic evaluation.
infectious disease evaluation for possible Lyme disease.
arthroscopic synovectomy.

Correct Answer: arthroscopic synovectomy.

Explanation:

DISCUSSION: The patient has synovial chondromatosis. The MRI scans show multiple small proscribed areas of signal intensity in the gutters and suprapatellar pouch, suggesting very small loose bodies. The arthroscopic view shows the classic appearance of multiple small chondral loose bodies. Synovial chondromatosis is a condition in which the synovium undergoes metaplasia, producing multiple chondral loose bodies that can subsequently ossify. The treatment of choice, removal of the loose bodies and arthroscopic synovectomy, results in a lower incidence of recurrence than other treatment methods.
REFERENCES: Coolican MR, Dandy DJ: Arthroscopic management of synovial chondromatosis of the knee: findings and results in 18 cases. J Bone Joint Surg Br
1989;71:498-500.
Ogilvie-Harris DJ, Saleh K: Generalized synovial chondromatosis of the knee: A comparison
of removal of the loose bodies alone with arthroscopic synovectomy. Arthroscopy
1994;10:166-170.

Question 60:

Options:

Subscapularis
Supraspinatus
Infraspinatus
Teres minor

Correct Answer: Subscapularis

Explanation:

Question 61:

Options:

Streptococcus pneumoniae
Staphylococcus aureus
Pseudomonas aeruginosa
Staphylococcus epidermis
Propionibacterium acnes

Correct Answer: Streptococcus pneumoniae

Explanation:

Question 62:

.What is the most appropriate treatment if instability is present at the time of evaluation?

Options:

TEA
Distal humeral replacement arthroplasty
Arthroscopic release with debridement
Soft-tissue interposition arthroplasty DISCUSSION.. The radiographs reveal ulnohumeral arthrosis with relative sparing of the radiocapitellar articulation secondary to underlying osteoarthritis. Arthrosis of the elbow joint in this young and active patient presents a treatment dilemma for the surgeon. Interposition arthroplasty allows for improved function with pain relief and no weight-lifting restrictions, as required with TEA. This option is an intermediate procedure that preserves bone stock and allows for conversion to a TEA if necessary. Conventional TEA would provide pain relief with improved range of motion, but activity limitation and lifetime weight restrictions make this an undesirable option. Arthroscopic debridement is not an option, considering the previous failure from this modality. Contraindications for soft-tissue interposition arthroplasty include elbow instability, active infection, and pain without motion loss. Common complications associated with this procedure include instability, infection, ulnar neuropathy, bone resorption, and heterotopic bone formation.

Correct Answer: Soft-tissue interposition arthroplasty DISCUSSION.. The radiographs reveal ulnohumeral arthrosis with relative sparing of the radiocapitellar articulation secondary to underlying osteoarthritis. Arthrosis of the elbow joint in this young and active patient presents a treatment dilemma for the surgeon. Interposition arthroplasty allows for improved function with pain relief and no weight-lifting restrictions, as required with TEA. This option is an intermediate procedure that preserves bone stock and allows for conversion to a TEA if necessary. Conventional TEA would provide pain relief with improved range of motion, but activity limitation and lifetime weight restrictions make this an undesirable option. Arthroscopic debridement is not an option, considering the previous failure from this modality. Contraindications for soft-tissue interposition arthroplasty include elbow instability, active infection, and pain without motion loss. Common complications associated with this procedure include instability, infection, ulnar neuropathy, bone resorption, and heterotopic bone formation.

Question 63:

Figure 46 shows the radiograph of an obese 12-year-old boy who has had left hip pain for the past 3 months. What is the best course of action?

Options:

Decreased activities and physical therapy
Left hip reduction and internal fixation
Left hip pinning in situ
Bilateral hip pinning in situ
Spica cast immobilization

Correct Answer: Left hip pinning in situ

Explanation:

Question 64:

Options:

Closed reduction and cast immobilization for 4 weeks, followed by therapy directed at regaining motion
Open reduction and internal fixation of the olecranon fracture, functional bracing of the humeral fracture, and therapy directed at regaining motion initiated at 2 weeks after surgery
Open reduction and internal fixation of the olecranon and humeral fractures, followed by therapy directed at regaining motion
Open reduction and internal fixation of the olecranon and humeral fractures, and splint immobilization for 4 weeks followed by therapy directed at regaining motion
Open reduction and internal fixation of the olecranon fracture, functional bracing of the humeral fracture, and therapy directed at regaining motion initiated at 4 weeks after surgery

Correct Answer: Open reduction and internal fixation of the olecranon and humeral fractures, followed by therapy directed at regaining motion

Explanation:

DISCUSSION: The floating elbow is best managed with early open reduction and internal fixation of the humeral and forearm fractures, followed by early range of motion. These fractures predispose the elbow to stiffness, and early range of motion is recommended.
REFERENCES: Solomon HB, Zadnik M, Eglseder WA: A review of outcomes in 18 patients with floating elbow. J Orthop Trauma 2003;17:563-570.
Yokoyama K, Itoman M, Kobayashi A, et al: Functional outcomes of “floating elbow” injuries in adult patients. J Orthop Trauma 1998;12:284-290.

Question 65:

Options:

glucosamine 1,500 mg/day and chondroitin sulfate 800 mg/day.
weight loss through dietary management and low-impact aerobic exercises.
arthroscopic debridement and lavage.
a valgus-directing brace.

Correct Answer: weight loss through dietary management and low-impact aerobic exercises.

Explanation:

Question 66:

Which of the following structures is predominantly composed of Type 1 collagen? Review Topic

Options:

Epithelial Basement Membrane
L4 disc nucleus pulposus
Anterior cruciate ligament
Medial femoral condyle articular cartilage
Dupuytren's contracture tissue

Correct Answer: Epithelial Basement Membrane

Explanation:

Question 67:

Options:

Hip arthroscopy with labrum repair
MRI arthrogram
Percutaneous screw fixation
CT scan with fine cuts

Correct Answer: CT scan with fine cuts

Explanation:

Question 68:

Which of the following areas of the vertebral segment has the highest ratio of cortical to cancellous bone? Review Topic

Options:

Thoracic vertebral bodies
Lumbar vertebral bodies
Sacrum
Pedicles of the lower lumbar spine
Pedicles of the thoracic spine

Correct Answer: Pedicles of the thoracic spine

Explanation:

Question 69:

What structure provides the major blood supply to the humeral head?

Options:

Posterior circumflex humeral artery
Anterior circumflex humeral artery, ascending branch
Nutrient humeral artery
Thoracoacromial artery, deltoid branch
Small arteries of the rotator cuff insertions

Correct Answer: Anterior circumflex humeral artery, ascending branch

Explanation:

DISCUSSION: The ascending branch of the anterior circumflex humeral artery provides
the major blood supply to the humeral head. The posterior circumflex humeral artery
supplies a much smaller portion of the proximal humerus. The nutrient humeral artery is the main blood supply for the humeral shaft. The thoracoacromial artery is primarily a muscular branch. The rotator cuff insertions contribute some blood supply to the tuberosities but not a major contribution.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.
Cushner MA, Friedman RJ: Osteonecrosis of the humeral head. J Am Acad Orthop Surg 1997;5:339-346.

Question 70:

What spinal nerves in the cauda equina are primarily responsible for innervation of the bladder?

Options:

L1, L2, and L3
L4 and L5
L5 and S1
S2, S3, and S4
Filum terminale

Correct Answer: S2, S3, and S4

Explanation:

Question 71:

Options:

The distal femoral lesion should undergo needle biopsy first.
Bone marrow biopsy should be done first.
Preoperative biopsy is not necessary because a metastatic process is present.
Biopsy is not necessary if the lesion demonstrates a standardized uptake value (SUV) greater than 3 on fluorodeoxyglucose positron emission tomography (PET) imaging. . DISCUSSION… This patient has widespread metastatic disease based on bone scan findings. According to a study by Rougraff and associates, CT scan of the chest, abdomen, and pelvis and laboratory studies will identify the primary site of disease in more than 85% of cases. When signs or symptoms of spinal cord compression are absent, total spine MR imaging probably is not needed. Biopsy alone is less accurate than staging in establishing a diagnosis. Bone marrow biopsy is used only if a hematopoietic tumor (myeloma, lymphoma) is diagnosed. Patients who develop hypercalcemia need hydration (with supplemental furosemide), bisphosphonates, and evaluation for cardiac arrhythmia. Hemodialysis and vitamin D therapy are not indicated, and fluid restriction would be contraindicated. Biopsy before intervention for pathologic lower-extremity fracture likely is not needed in a scenario with numerous bone lesions and pulmonary metastases. The absence of a clear primary tumor of origin suggests this is unlikely to be a renal cell carcinoma for which preoperative embolization would be considered before an intralesional procedure. Tissue should be obtained at the time of surgery. Although an SUV greater than 3 is suspicious for malignancy, activity on PET scan should not influence the need for biopsy in this scenario.

Correct Answer: Preoperative biopsy is not necessary because a metastatic process is present.

Explanation:

t(12;22)(q13;q12-3)
t(X;18)(p11.2;q11.2)
t(11;22)(q24;q12)
t(1;3)(p36.3;q25)

Question 72:

Options:

Flexion and extension lateral radiographs
MRI
Myelogram
Diskogram
Bone scan with SPECT

Correct Answer: Bone scan with SPECT

Explanation:

A bone scan with SPECT is very sensitive and specific for spondylolysis not seen on initial radiographs. MRI can sometimes visualize spondylolysis, but it is not as sensitive nor as specific as a bone scan with SPECT. Flexion and extension views
have no role in the evaluation of the patient who presents with classic spondylolysis-type symptoms. The most sensitive physical examination finding is pain with back extension. Oblique radiographs can be obtained, but they are not as sensitive or specific as a bone scan with SPECT. The patient does not have any signs of a disk problem; therefore, an evaluation of the disk is not helpful.
(SBQ13PE.79) A 17-year-old male American football lineman presents with low back pain of insidious onset that is somewhat worse with activity. He has no neurologic complaints, night pain or fevers. His symptoms have been present for a few years but this is the first time he has sought medical attention. What physical examination finding is most likely to be found in this clinical scenario?
Review
Topic
Popliteal angle of 5 degrees
Heel cord tightness
Increased femoral anteversion
Pain with lumbar extension in single leg stance
Numbness of the skin of the anterolateral calf and dorsum of the foot
The patient demographics and clinical presentation are consistent with lumbar spondylolysis. Pain with lumbar extension is the most common physical exam finding.
Office assessment of the patient with spondylolysis should note pertinent negatives that would signify other causes of back pain. The history is most commonly negative for neurologic symptoms such as weakness or numbness, although patients will occasionally have radicular pain. On exam, patients may have localized spasm or tenderness, step off (if there is spondylolisthesis), hamstring tightness. The most common finding is pain with lumbar extension.
McCleary et al. review the diagnosis and treatment of spondylolysis in athletes. They identify three types of patients with spondylolysis: (1) female dancer or gymnast who is hyperlordotic, with increased motion and flexibility, (2) male weightlifter or football player undergoing a growth spurt, with decreased motion and flexiblity, especially of the spinal erectors, and (3) a novice athlete undergoing vigorous preparation for a new sport, with poor core strength and flexibility.
Incorrect

Question 73:

A 30-year-old patient has acetabular dysplasia and moderate secondary osteoarthrosis. Which of the following studies will best help predict the success of periacetabular osteotomy?

Options:

High-resolution CT with coronal and sagittal reconstructions
Glycosaminoglycan MRI
Functional radiographic or fluoroscopic evaluation
Gadolinium-contrast arthrography with MRI
Routine AP and lateral radiographs

Correct Answer: Functional radiographic or fluoroscopic evaluation

Explanation:

Question 74:

A patient with rheumatoid arthritis with both ankle and subtalar involvement was treated as shown in Figures 11a and 11b. What complication is unique to this type of fixation?

Options:

Late rotatory deformity
Limb-length discrepancy
Talar osteonecrosis
Tibial stress fracture
Hardware failure

Correct Answer: Tibial stress fracture

Explanation:

DISCUSSION: The interlocking screws at the proximal end of the rod can act as a stress riser and lead to fracture. Postoperative pain at this level should prompt inclusion of this diagnosis in the differential. Removing the screws following bone union can decrease the chances of this occurring. A short rod that avoids the diaphyseal area may also be beneficial. Rotatory deformity is controlled by the perpendicularly oriented distal transfixion screws. Talar osteonecrosis would be unusual since the dissection can be minimized with an intramedullary rod. Any type of hardware can fail if the construct does not lead to a solid arthrodesis.
REFERENCES: Nunley JA, Pfeffer GB, Sanders RW, et al (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 236-237.
Thordarson DB, Chang D: Stress fractures and tibial cortical hypertrophy after tibiotalocalcaneal arthrodesis with an intramedullary nail. Foot Ankle Int 1999;20:497-500.
Hammett R, Hepple S, Forster B, et al: Tibiotalocalcaneal (hindfoot) arthrodesis by retrograde intramedullary nailing using a curved locking nail: The results of 52 procedures. Foot Ankle Int 2005;26:810-815.

Question 75:

Options:

Kaposi sarcoma
Squamous cell carcinoma
Pigmented basal cell carcinoma
Melanoma
Basillary angiomatosis

Correct Answer: Melanoma

Explanation:

Question 76:

What structure is 7cm from the acromion and at greatest risk of injury during a deltoid splitting approach for a proximal humerus fracture?

Options:

Radial nerve
Suprascapular nerve
Axillary nerve
Axillary artery
Axillary vein

Correct Answer: Radial nerve

Explanation:

Question 77:

Antegrade femoral nailing has an increased rate of which of the following when compared to retrograde femoral nailing?

Options:

Varus malalignment
Union rate
Operative time
Subsequent operative procedures
Hip pain

Correct Answer: Varus malalignment

Explanation:

Question 78:

Posttraumatic physeal arrest is most common at which of the following locations?

Options:

Proximal tibia
Proximal humerus
Distal radius
Distal humerus
Distal tibia

Correct Answer: Distal tibia

Explanation:

DISCUSSION: Posttraumatic physeal arrest occurs most commonly in the distal medial tibia. Using MRI, Echlund and associates confirmed this finding. Arrest of the distal radius and proximal humerus are rare after trauma. Traumatic injuries of the distal femoral and distal ulnar physis have a high incidence of growth arrest as well.
REFERENCES: Ecklund K, Jaramillo D: Patterns of premature physeal arrest: MR imaging of 111 children. AJR Am J Roentgenol 2002; 178:967-972.
YAtotoartanadQpyiQter
GN: Physeal bridge resection. J Am Acad Orthop Surg 2005; 13:4
Figure 64a Figure 64b

Question 79:

Options:

C5-C7 nerve roots; upper/middle trunks; anterior division; lateral cord
C5-C6 nerve roots; upper trunk; posterior division; posterior cord
C5-C6 nerve roots; upper trunk
C5-C7 nerve roots
C8-T1 nerve root; lower trunk; anterior division; medial cord

Correct Answer: C8-T1 nerve root; lower trunk; anterior division; medial cord

Explanation:

Question 80:

Options:

Increased rate of union
Decreased rate of infection
Shorter operative time
Lower rates of hip pain
Lower rates of knee pain

Correct Answer: Increased rate of union

Explanation:

Question 81:

Options:

closed reduction and a double spica cast.
skeletal traction for 3 weeks, followed by a double spica cast.
reduction and internal fixation crossing the physis if necessary.
reduction and internal fixation with primary bone grafting.
skin traction.

Correct Answer: reduction and internal fixation crossing the physis if necessary.

Explanation:

Question 82:

Options:

with varus malalignment
with valgus malalignment
with external rotation malalignment
with internal rotation malalignment
with no malalignment

Correct Answer: with varus malalignment

Explanation:

When the lesser trochanter (LT) profile is larger than the uninjured side, the proximal fragment is externally rotated. This leads to an overall internal rotation (IR) malalignment of the distal fragment. Malalignment is described based on the distal fragment relative to the proximal fragment. For more proximal femoral fractures, the proximal fragment tends to be flexed and externally rotated due to the iliopsoas. Matching rotation requires external rotation of the distal fragment when the patient is supine on a fracture table.
Rotational malalignment is the most common complication of intramedullary nailing of a comminuted diaphyseal femoral fracture. The rotational profile of the lesser trochanter can be used to evaluate rotational alignment. The proximal femur is rotated until a neutral position is obtained as judged by the radiographic profile of the lesser trochanter. If the AP image shows a smaller lesser trochanter, there is IR of the LT. A larger LT indicates external rotation (ER) of the LT.
Jaarsma et al. describe CT imaging in determining rotational alignment. They note that the incidence of post-nailing malalignment > 10 ° is 40%, > 15 ° is 20-30%, and
> 20 ° is 16%. They also note that patients with ER deformities have more symptoms than those with IR deformities, and that small deformities <15 ° give rise to less complaints. This is because ER deformities lead to compensation with hip retroversion, which causes more symptoms than hip anteversion when compensating for IR deformities.
Incorrect Answers:
(SBQ12TR.37) A 44-year-old male presents with the isolated injury seen in Figure A after a motor vehicle accident and underwent the operative treatment seen in Figure B within 8 hours from the time of incident. Which of the following complications is this patient at highest risk of developing?
Pulmonary embolus
Periprosthetic fracture
Contralateral hip fracture
Osteonecrosis
Infection
This young male patient has sustained a displaced femoral neck fracture and underwent open reduction internal fixation with 3 cannulated screws. Based on the available options, the patient is most at risk of developing osteonecrosis of the femoral head.
Femoral neck fractures in young patients typically are the result of a high-energy trauma. Fracture displacement has been shown to disrupt vascular supply to the femoral head by interrupting retinacular vessels and ligament teres vascularization, as well as increasing intracapsular pressure, producing a tamponade effect. The incidence of osteonecrosis in patients younger than 60 years with displaced femoral neck fractures has been shown to be between 15-30%. Quality of reduction is one key factor that has been shown to influence outcomes postoperatively.
Loizou et al. prospectively studied 1,023 patients who sustained an intracapsular hip fracture that was treated with internal fixation using standard fixation modalities. They showed that osteonecrosis was less common for undisplaced (4.0%) than for displaced fractures (9.5%). The population at greatest risk were women younger than the age of 60 with displaced fractures.
Barnes et al. review subcapital hip fractures. They found that late segmental collapse was more common in displaced fractures in women younger than age 75 years than in those older than age 75 years treated with internal fixation.
Figure A shows a displaced, Garden 3/Pauwels I hip fracture. Figure B shows anatomical fixation with 3 cannulated screws.
Incorrect Answers:

Question 83:

In Ewing’s sarcoma, neoplastic properties are thought to be related to a

Options:

environmental toxins.
a prior history of osteomyelitis.
a prior history of viral illness.
a prior history of trauma.
translocation of chromosomes.

Correct Answer: translocation of chromosomes.

Explanation:

Question 84:

Figure 93 shows the axial T2-weighted MRI scan of the lumbar spine of a 70-year-old man. The arrow points to which of the following structures? Review Topic

Options:

Lamina
Facet joint
Lumbar synovial cyst
Ligamentum flavum
Epidural space

Correct Answer: Lamina

Explanation:

The ligamenta flava (singular, ligamentum flavum, Latin for yellow ligament) are ligaments that connect the laminae of adjacent vertebra, all the way from the axis to the first segment of the sacrum. In T2-weighted sequencing, ligamentous structures possess a low signal intensity. The ligamentum in this patient is markedly thickened, resulting in severe spinal stenosis. The epidural space lies ventral and medial to the ligamentum flavum and should possess a high signal intensity secondary to the presence of cerebrospinal fluid. However, in the case of high-grade stenosis, there may be little if any cerebrospinal fluid present, making the epidural space and central canal difficult to identify. A lumbar synovial cyst should also have high signal intensity because of the presence of synovial fluid.
(SBQ12SP.14) A 36-year-old male presents with acute onset of right buttock and leg pain following lifting a heavy object. On physical exam he has weakness to knee extension, numbness over the medial malleolus, and a decreased patellar reflex. Which of the following would most likely explain this clinical presentation.
Review
Topic
Lumbar arachnoiditis
L4/L5 paracentral disc herniation
L3/L4 far lateral (foraminal) disc herniation
L4/L5 far lateral (foraminal) disc herniation
L5/S1 far lateral (foraminal) disc herniation
The clinical presentation is consistent with a L4 radiculopathy. A L4/L5 far lateral (foraminal) disc herniation would compress the exiting root (L4) and cause these symptoms.
The location of a prolapsed lumbar disc determines its symptoms. Central disc herniations may give rise to back pain or cauda equina syndrome. Paracentral disc herniations (90-95% of cases) affect the traversing nerve root. Far lateral disc herniations (5-10%) affect the exiting nerve root.
Gregory et al. summarize physical signs in lumbar disc herniation. They state that the straight-leg-raise is the most sensitive (73-98% sensitive) test and the crossed straight-leg-raise is the most specific (88-98% specific) test for lumbar disc herniation. Other specific tests include weak ankle dorsiflexion (89% specific), absent ankle reflex (89% specific), and calf wasting (94% specific, but a late finding).
Illustration A shows how a paracentral L4/L5 disc herniation affects the traversing L5 root, but a far lateral L4/L5 disc herniation affects the L4 root. Illustration B shows the dermatomal distribution of pain with root involvement from L3 to S1.
Incorrect Answers:

Question 85:

Which of the following is the only nonreversible effect of anabolic steroids?

Options:

Muscle hypertrophy
Alterations in high density lipoprotein (HDL) and low density lipoprotein (LDL) ratios
Alopecia
Personality effects
Acne

Correct Answer: Alopecia

Explanation:

Question 86:

Options:

an elastic bandage, cold packs, and weight bearing as tolerated.
non-weight-bearing and a CT scan of the talus.
cast immobilization for 10 days, followed by progressive rehabilitation.
cast immobilization for 6 weeks, followed by progressive rehabilitation.
stirrup splinting, cold packs, and aggressive rehabilitation.

Correct Answer: non-weight-bearing and a CT scan of the talus.

Explanation:

Question 87:

Options:

physical therapy to stretch the tight structures.
a humeral rotational osteotomy.
anterior shoulder release and posterior muscle transfers.
anterior shoulder release.
shoulder fusion.

Correct Answer: a humeral rotational osteotomy.

Explanation:

Question 88:

Options:

Correction of the flatfoot deformity
Achilles tendon lengthening followed by orthotic support
Excision of the tarsal coalition
Sinus tarsi debridement
Triple arthrodesis

Correct Answer: Excision of the tarsal coalition

Explanation:

DISCUSSION: The patient has a calcaneonavicular tarsal coalition. Symptoms of calcaneonavicular coalitions typically are seen between the ages of 10 and 14 years. The cause of pain has not been clearly established. It has been postulated that the coalition stiffens with maturity and microfractures can result, producing pain. Resection of a calcaneonavicular coalition generally has been associated with a satisfactory result. Soft-tissue interposition, most commonly using the extensor digitorum brevis muscle, appears to be helpful. A hindfoot arthrodesis (usually triple) would be reserved if coalition resection proves to be unsuccessful. Achilles tendon lengthening and orthotic support, as well as debridement of the sinus tarsi, are not expected to result in a satisfactory outcome. The patient does not have a flatfoot deformity.
REFERENCES: Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 757-765.
Lemley F, Berlet G, Hill K, et al: Current concepts review: Tarsal coalition. Foot Ankle Int 2006;27:1163-1169.

Question 89:

The medial collateral ligament complex of the elbow originates on what portion of the medial epicondyle?

Options:

Anterior and inferior
Anterior and superior
Anterior and central
Posterior and superior
Posterior and inferior

Correct Answer: Anterior and inferior

Explanation:

Question 90:

Options:

closed reduction and percutaneous pinning.
implant arthroplasty.
arthrodesis.
volar plate arthroplasty.
resection arthroplasty.

Correct Answer: volar plate arthroplasty.

Explanation:

DISCUSSION: The patient has a neglected PIP joint fracture-dislocation with comminution involving more than 40% of the volar articular surface of the middle phalanx. Volar plate arthroplasty has been advocated for the treatment of acute unstable and chronic dorsal fracture-dislocations. The volar plate is incised laterally and released from the collateral ligaments. The volar fragments of the middle phalanx are removed and a trough is created for advancement of the volar plate, which is secured with sutures secured on the dorsum of the middle phalanx beneath the extensor mechanism.
REFERENCES: Dionysian E, Eaton RG: The long-term outcome of volar plate arthroplasty of the proximal interphalangeal joint. J Hand Surg Am 2000;25:429-437.
Eaton RG, Malerich MM: Volar plate arthroplasty of the proximal interphalangeal joint: A review of ten years’ experience. J Hand Surg Am 1980;5:260-268.
Deitch MA, Kiefhaber TR, Comisar BR, et al: Dorsal fracture dislocations of the proximal interphalangeal joint: Surgical complications and long-term results. J Hand Surg Am 1999;24:914-923.

Question 91:

03 What is the most common site of fracture because of osteolysis following cementless total hip arthroplasty with an extensively porus-coated femoral component?

Options:

Central acetabulum
Ischial ramus
back answer
Greater trochanter
Between the lesser trochanter and the stem tip
Femoral stem tip 72.03

Correct Answer: back answer

Explanation:

Again referenced article is not helpful. Here is the thought process. Porous coating allows for bony ingrowth, and
creates stress shielding. The force is seen through the femoral head into the stem and transfers to the bone at areas of
ingrowth and transmitted distally. As a result the part being skipped is the greater trochanter and leads to osteolysis by Wolf’s law and can result in fracture.
The osteolysis created about the acetabulum is due an inflammatory mechanism imparted on the wear debris from the
bearing surfaces. This osteolysis rarely creates fractures.
The fractures about the stem are most commonly caused by the difference in modulus between the stem and bone
back to this
question next question

Question 92:

Options:

Grade III chondrosis of the proximal patella
Caton-Deschamps ratio of 1:1
Tibial tubercle-trochlear groove (TT-TG) distance of 21 mm
Q angle of 17 degrees

Correct Answer: Grade III chondrosis of the proximal patella

Explanation:

DISCUSSION
TTO is a common treatment for patellofemoral instability. The angle of correction must be customized to each patient’s anatomy. For this patient, the orthopaedic surgeon plans an osteotomy that will both anteriorize and medialize the tubercle. This will consistently result in
a change of patellofemoral kinematics and contact pressures. Medialization decreases lateral and increases medial patellofemoral contact pressures, and anteriorization shifts contact pressures from distal to proximal. Significant anteriorization may not be desired in a patient with proximal patellar chondrosis unless a concomitant chondral procedure is performed as well. The patellar height (Caton-Deschamps ratio) is normal, precluding the need for distalization but not medialization. The TT-TG distance, at more than 20 mm, is a strong indication for osteotomy. The Q angle, although a less precise indicator of malalignment, is also elevated and would be considered an indication for osteotomy.
CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 41
A healthy, active 18-year-old man has acute-onset right knee pain and an inability to fully extend his knee following an attempt to stand from a seated position yesterday. He sustained a noncontact injury to his right knee while playing basketball 2 years ago and underwent primary anterior cruciate ligament (ACL) reconstruction with bone-patella-tendon-bone autograft and medial meniscus repair. He sustained another noncontact injury to the same knee 8 months later and underwent a revision ACL reconstruction using soft-tissue allograft and revision medial meniscus repair. He reports multiple episodes of “giving way” of his knee, but no pain prior to yesterday’s acute injury.

Question 93:

The patient undergoes a mobile-bearing UKA. When compared to a fixed-bearing metal-backed unicompartmental arthroplasty, this procedure is associated with a

Options:

higher risk for failure attributable to wear.
higher risk for failure attributable to bearing spinout.
lower risk for loosening.
lower risk for arthritic progression of the lateral compartment.

Correct Answer: higher risk for failure attributable to bearing spinout.

Explanation:

Question 94:

Options:

Arthroscopic debridement
Two-stage total knee revision arthroplasty
Resection arthroplasty without an antibiotic impregnated cement spacer
Knee fusion

Correct Answer: Two-stage total knee revision arthroplasty

Explanation:

DISCUSSION:
This complication is best addressed with either a single-stage or two-stage total knee arthroplasty. A recent report suggests that a single-stage arthroplasty can be effective, although many surgeons would perform a two-stage procedure with an articulating or static spacer. Arthroscopic would be non-effective, especially given 4 weeks of symptoms. Resection arthroplasty without a spacer would leave an unstable
and poorly functioning extremity. Knee fusion should be used as a salvage procedure.

Question 95:

Figure 43 shows the lateral radiograph of a 12-year-old boy with mild osteogenesis imperfecta who injured his left elbow after pushing his brother. Treatment should consist of

Options:

closed reduction and cast immobilization.
closed reduction and percutaneous pinning.
open reduction and fixation using an absorbable suture.
open reduction and fixation using two Kirschner wires and a figure-of-8 tension band of absorbable suture.
open reduction and fixation using an intramedullary screw.

Correct Answer: open reduction and fixation using two Kirschner wires and a figure-of-8 tension band of absorbable suture.

Explanation:

Question 96:

Options:

Snug fitting shoe to block side-to-side motion that is common after this procedure
Leather sole shoe to prevent catching the shoe on carpet which is common with crepe-soled shoes
Lateral wedge on the shoe to offset the external rotation during the toe-off phase of gait commonly seen after this procedure
Steel shank to extend the foot lever and prevent deformity at the toe break
Custom-made shoe to provide the best possible fit and function

Correct Answer: Steel shank to extend the foot lever and prevent deformity at the toe break

Explanation:

DISCUSSION: The steel shank is a flat 1-inch steel strip placed between layers of the shoe to extend the foot lever and prevent deformity at the toe break seen following a partial first ray amputation. A rocker sole may be added as well to facilitate transition from foot flat to the toe-off phase of gait. Proper shoe fit is important, but “snug” fitting shoes in a patient with peripheral neuropathy and likely fluctuations in volume from intermittent swelling are to be avoided. A custom shoe is an unnecessary expense. The patient has at least 10 degrees of dorsiflexion at the ankle with an intact anterior tibialis muscle; therefore, catching the sole on carpeting should not be a problem.
REFERENCES: Philbin TM, Leyes M, Sferra JJ, et al: Orthotic and prosthetic devices in partial foot amputations. Foot Ankle Clin 2001;6:215-228.
Pinzur MS, Dart HC: Pedorthic management of the diabetic foot. Foot Ankle Clin 2001;6:205-214.

Question 97:

Genetic mutations that may result in the cervical abnormalities noted in the figures generally affect the

Options:

embryonic process of neurulation.
embryonic process of gastrulation.
segmentation or resegmentation of somites.
differentiation of somites into sclerotome, myotome, and dermatome segments.

Correct Answer: segmentation or resegmentation of somites.

Explanation:

Question 98:

Which of the following procedures is included in third-generation cement technique?

Options:

Addition of antibiotic to the cement
Monomer chilling to increase working time and lower viscosity
Porosity reduction through centrifugation and/or vacuum mixing
Use of a cemented, polished, tapered stem
Placement of a plastic tube distally to allow fluid to escape

Correct Answer: Porosity reduction through centrifugation and/or vacuum mixing

Explanation:

Question 99:

- The diagnostic distinction between a benign enchondroma and a low- grade intramedually chondrosarcoma is based primarily on the

Options:

clinical history and radiographic findings.
technetium bone scan
flow cytometry pattern of extracted chondrocytes
immunohistochemical staining patterns of a biopsy specimen
histologic features of a biopsy specimen stained with hematoxylin-cosin

Correct Answer: clinical history and radiographic findings.

Explanation:

Question 100:

What is the most appropriate next step in the work-up of a patient with the asymptomatic lesion shown in Figure 23?

Options:

Open biopsy
Needle biopsy
Observation
CT-guided radiofrequency ablation
Antibiotics

Correct Answer: Observation

Orthopedic Surgery Board Review MCQs: Arthroplasty, Trauma & Spine Part 255

Orthopedic Surgery Board Review MCQs: Hip, Shoulder, Elbow, Arthroplasty & Tumor | Part 87

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 87

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index