OITE & ABOS Orthopedic Board Review MCQs: Part 10

About This Board Review Set

This is Part 10 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 10

This module focuses heavily on: Ankle, Arthroplasty, Fracture, Knee, Revision.

Sample Questions from This Set

Sample Question 1: A 44-year-old farmer involved in a rollover accident on his tractor sustained an L1 burst fracture with a 20% loss of anterior vertebral body height, 30% canal compromise, and 15 degrees of kyphosis. He remains neurologically intact. The pr...

Sample Question 2: During a revision total knee arthroplasty (TKA), there is difficulty gaining exposure and a tibial tubercle osteotomy (TTO) is performed. The final components are stable and include a stemmed tibial component that bypasses the osteotomy sit...

Sample Question 3: -Work-related injuries to the lower back are most often related to which of the following risk factors?...

Sample Question 4: A 34-year-old male has persistent anterolateral ankle pain after a snowboarding injury 1 week ago and is unable to bear weight. Radiographs taken in the emergency room were negative. What is the next step in management?...

Sample Question 5: Following an episode of transient quadriplegia in contact sports, an athlete’s return to play is absolutely contraindicated when...

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

A 44-year-old farmer involved in a rollover accident on his tractor sustained an L1 burst fracture with a 20% loss of anterior vertebral body height, 30% canal compromise, and 15 degrees of kyphosis. He remains neurologically intact. The preferred initial course of action should consist of

Explanation

DISCUSSION: Surgical decompression is unnecessary in a patient with no neurologic deficit and canal compromise of less than 50%. A compression deformity of less than 50% and kyphosis of less than 30 degrees may be successfully treated with a TLSO extension brace. Deformity in this range will reliably heal with minimal risk for late deformity or residual pain. Although some studies suggest 6 weeks of bed rest as treatment, early mobilization and bracing is preferred.
REFERENCES: Hartman MB, Chrin AM, Rechtine GR: Nonoperative treatment of thoracolumbar fractures. Paraplegia 1995;33:73-76.
Chow GH, Nelson BJ, Gebhard JS, Brugman JL, Brown CW, Donaldson DH: Functional outcome of thoracolumbar burst fractures managed with hyperextension casting or bracing and early mobilization. Spine 1996;21:2170-2175.
Kraemer WJ, Schemitsch EH, Lever J, McBroom RJ, McKee MD, Waddel JP: Functional outcome of thoracolumbar burst fractures without neurological deficit. J Orthop Trauma 1996;10:541-544.

Question 2

During a revision total knee arthroplasty (TKA), there is difficulty gaining exposure and a tibial tubercle osteotomy (TTO) is performed. The final components are stable and include a stemmed tibial component that bypasses the osteotomy site. The tibial tubercle is reattached to the osteotomy site with multiple cerclage wires. Following closure of the arthrotomy, the knee is flexed to 90 degrees, and there is no observed displacement of the TTO. What is the best next step in postsurgical rehabilitation?

Explanation

DISCUSSION
TTO is a recognized technique for improving exposure when performing TKA in a stiff knee. TTO has been reported to enhance surgical exposure and not adversely affect outcomes after TKA, but there is a 5% complication rate. The postsurgical routine following TTO
includes full weight-bearing activity and range of motion as tolerated. Caution should be exercised when manipulation is performed to improve knee flexion following a TTO.

Question 3

Work-related injuries to the lower back are most often related to which of the following risk factors?

Explanation

The strongest variable for predicting subsequent low back pain is current or prior low back pain, defined at time loss for back pain during the previous 6 months or at the time of initial examination; relative risk 60%. Smoking was associated with a 40% increased risk of reporting back pain.

Question 4

A 34-year-old male has persistent anterolateral ankle pain after a snowboarding injury 1 week ago and is unable to bear weight. Radiographs taken in the emergency room were negative. What is the next step in management?

Explanation

DISCUSSION: Fractures of the lateral process of the talus are frequently overlooked and should always be considered in the differential diagnosis of ankle pain in snowboarders. The common mechanism for fracture is dorsiflexion of the ankle and inversion of the hindfoot.
The reference by Vlahovich et al is a case report of a talus fracture in a snowboarder and argues the importance of CT scans in evaluating these injuries as radiographs may fail to show the injury and amount of displacement and comminution of the fracture.
The reference by Tucker et al is a review of the literature which emphasized the importance of early diagnosis to avoid long term complications. They recommend short leg casting for nondisplaced fractures and surgery for displaced or comminuted fractures.

Question 5

Following an episode of transient quadriplegia in contact sports, an athlete’s return to play is absolutely contraindicated when

Explanation

DISCUSSION: Return to play decisions after traumatic spinal or spinal cord injury are not always clear-cut and often must be made on a patient-by-patient basis. The Torg ratio has been found to have low sensitivity in patients with large vertebral bodies. Abnormal electromyographic studies can persist in the face of normal function and do not define spinal injury. Duration of quadriplegia is not related to anatomic pathology. Findings on MRI scans or contrast-enhanced CT scans consistent with stenosis include lack of a significant cerebrospinal fluid signal around the cord, bony or ligament hypertrophy, or disk encroachment. Based on these findings, return to play should be avoided.
REFERENCES: Cantu RC, Bailes JE, Wilberger JE Jr: Guidelines for return to contact or collision sport after a cervical spine injury. Clin Sports Med 1998;17:137-146.
Herzog RJ, Wiens JJ, Dillingham MF, Sontag MJ: Normal cervical spine morphometry and cervical stenosis in asymptomatic professional football players: Plain film radiography, multiplanar computer tomography, and magnetic resonance imaging. Spine 1991;16:178-186.
Bailes JE, Hadley MN, Quigley MR, Sonntag VK, Cerullo LJ: Management of athletic injuries of the cervical spine and spinal cord. Neurosurgery 1991;29:491-497.

Question 6

A 52-year-old woman with diabetes mellitus has had a plantar foot ulcer under the second metatarsal head for the past week. The patient had a similar ulcer 2 months ago, and total contact casting resulted in healing. Examination reveals no signs of infection. What procedure will best prevent recurrence of the ulcer?

Explanation

DISCUSSION: The contracted Achilles tendon leads to increased forefoot pressure, thus increasing the risk for ulceration in neuropathic patients. Several studies have shown the benefit of Achilles tendon lengthening to heal and prevent forefoot ulceration in these patients. The flexor hallucis longus transfer is used for chronically torn/deficient Achilles tendons, not a contracted Achilles tendon. The Jones procedure works well for the first ray but does not help to alleviate pressure under the second ray. Peripheral bypass surgery is unnecessary because the ulcer healed during the initial treatment, indicating that the patient has adequate circulation. The posterior tibial tendon transfer is used for foot drop or other neuromuscular conditions to correct deformity and increase function. It is not used for forefoot ulcers in patients with diabetes mellitus.
REFERENCES: Armstrong DG, Stacpoole-Shea S, Nguyen H, et al: Lengthening of the Achilles tendon in diabetic patients who are at high risk for ulceration of the foot. J Bone Joint Surg Am 1999;81:535-538.
Meuller MJ, Sinacore DR, Hastings MK, et al: Effect of Achilles tendon lengthening on neuropathic plantar ulcers: A randomized clinical trial. J Bone Joint Surg Am

2003;85:1436-1445.

Question 7

Based on the injury shown on the axial MRI scan of the shoulder in Figure 1, what other pathology should be closely examined for during surgery?

Explanation

The axial MRI scan reveals a subluxated biceps tendon. In the study by Koh and associates, 85% of patients with a biceps subluxation on MRI were found to have a subscapularis tear at the time of arthroscopy. These are not always obvious on the MRI, and close inspection of the leading edge/upper border of the subscapularis tendon at the time of arthroscopy is necessary. Although supraspinatus tears, SLAP tears, and Bankart tears can all occur in conjunction with a biceps subluxation, none have been shown to be strongly correlated with this pathology, nor as
specific to this pathology.

Question 8

What is the most important factor regarding the risk of recurrent instability in a patient with an acute anterior dislocation of the shoulder?

Explanation

DISCUSSION: The recurrence rate of anterior dislocation of the shoulder after the first episode in athletes younger than age 20 years is thought to be as high as 90%, making surgery after the initial episode a consideration. The rate drops from 50% to 75% in the 20- to 25-year age group and down to 15% in patients older than age 40 years. An excellent prospective study of 257 patients in Sweden showed that there was no difference in those who did or did not complete 3 weeks of immobilization. The study also showed variability among different age groups in the importance of athletic participation; athletes in the 12- to 22-year age group had a higher recurrence rate, whereas the more sedentary patients in the 23- to 29-year age group had a higher rate.
REFERENCES: Hovelius L: The natural history of primary anterior dislocation of the shoulder in the young. J Orthop Sci 1999;4:307-317.
Simonet WT, Cofield RH: Prognosis in anterior shoulder dislocation. Am J Sports Med 1984;12:19-24.

Question 9

Figures 29a and 29b show the AP radiograph and CT scan of a 70-year-old man who has left thigh pain. Serum protein electrophoresis shows a monoclonal gammopathy. Additional radiographs of the femur show other lesions. Management should consist of

Explanation

DISCUSSION: The underlying diagnosis is multiple myeloma. Because the patient has a large lucent lesion in the peritrochanteric region of the left proximal femur, the risk of pathologic fracture is high. Consideration should be given to prophylactic internal fixation with a locked intramedullary rod. The lesion does not appear to be a sarcoma requiring wide resection and endoprosthetic reconstruction. Neither chemotherapy nor radiation therapy alone is likely to result in long-term stabilization of the proximal femur. Postoperative treatment with bisphosphonates and radiation therapy is indicated to decrease the risk of future pathologic fractures. The patient should also be referred to a medical oncologist for medical management.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, p 364.
Mirels H: Metastatic disease in long bones: A proposed scoring system for diagnosing impending pathologic fractures. Clin Orthop 1989;249:256-264.

Question 10

A 78-year-old patient undergoing revision total knee arthroplasty has bone loss throughout the knee at the time of revision. A distal femoral augment is used to restore the joint line. One month after surgery, the patient reports pain and is unable to ambulate. A lateral radiograph is shown in Figure 34. What is the most likely etiology of this problem?

Explanation

DISCUSSION: Instability is a leading cause of failure following total knee arthroplasty. Instability can present as global instability, extension gap (varus/valgus) instability, or flexion gap (anterior/posterior) instability. Treatment options are numerous based on the exact pathology. The radiograph reveals anterior/posterior instability with dislocation consistent with flexion gap instability. A loose flexion gap can allow the femoral component to ride above the tibial cam post mechanism, resulting in dislocation. Distal femoral augments treat extension gap instability, whereas tibial augments can treat both flexion and extension gap instability. Posterior condyle augments at the distal femur can also be used to treat flexion gap instability. Flexion gap instability is further aggravated by extension mechanism incompetence. Note the excessively thin patella on the lateral radiograph.
REFERENCES: Pagnano MW, Hanssen AD, Lewallen DG, et al: Flexion instability after primary cruciate retaining total knee arthroplasty. Clin Orthop 1998;356:39-46.
McAuley J, Engh GA, Ammeen DJ: Treatment of the unstable total knee arthroplasty. Inst Course Lect 2004;53:237-241.
Naudie DD, Rorabeck CH: Managing instability in total knee arthroplasty with constrained and linked implants. Instr Course Lect 2004;53:207-215.

Question 11

-If a physician elects to shorten a femur by 4 cm for traumatic bone loss treatment and places an intramedullary nail for fixation, which deformity will be created in the lower extremity?

Explanation

Question 12

Figure 100 is the MRI scan of a 52-year-old runner who has right knee pain that has been occurring 10 minutes into her run for 2 months. On examination, she has tenderness over the lateral epicondyle. Her Ober test result is positive. What is the most appropriate initial treatment? Review Topic

Explanation

Iliotibial band syndrome (ITBS) is a common cause of lateral knee pain in runners. Potential etiologies for the pain include repetitive friction, compression, and bursal inflammation. An Ober test is used to assess iliotibial band tightness. With the patient lying on the unaffected side, the affected leg is abducted and extended. The test result is positive if the examiner is unable to adduct the leg from this position. An MRI scan can be helpful in making the diagnosis, but a negative MRI scan does not rule out ITBS. Studies have reported increased signal intensity on T2-weighted images deep to the iliotibial band adjacent to the lateral epicondyle, with thickening of the iliotibial band. Nonsurgical treatment is most appropriate initially and involves activity modification, ice, anti-inflammatory medications, and stretching. Corticosteroid injection to the iliotibial bursa is also an option to treat acute pain. After the initial inflammation improves, a strengthening program is started. Multiple surgical procedures have been described for recalcitrant cases, including iliotibial band excision, Z-lengthening, and iliotibial band bursectomy.

Question 13

A patient is seen in the emergency department after a motor vehicle accident. He reports right hip pain and chest pain. Initial hypotension has responded to a fluid bolus. Radiographs reveal a posterior hip dislocation with a small posterior acetabular wall fracture. You are called at home and informed of the findings. What is the next most appropriate step in management? Review Topic

Explanation

An immediate reduction of the hip is required. Transfer to a trauma center may be indicated to treat a possible chest injury and the acetabular fracture. Reduction of the hip dislocation should be considered emergent and should be performed prior to transfer. Additional diagnostic studies prior to hip reduction are not necessary. Most hip dislocations can be reduced closed and this is the preferred management.

Question 14

What is the main biologic effect of aggrecan in cartilage? Review Topic

Explanation

Aggrecan binds hyaluronic acid to attract water, which accounts for its hydrophilic property.
Aggrecan is the predominant proteoglycan in cartilage. It contains a large number of negatively charged sequences that attract water called sulfated glycosaminoglycan (GAG) chains. Its the N-terminal globular domain of aggrecan that binds hyaluronan to form huge aggregates. Together with its chondroitin sulfate chains, they help to create a hydrophilic viscous gel that decreases the coefficient of friction as well as to help absorb compressive loads.
Ulrich-Vinthe et al. reviewed the biology of articular cartilage. They report that matrix metalloproteinases and aggrecanases play a major role in aggrecan degradation and their production is upregulated by mediators associated with joint inflammation and overloading.
Illustration A shows a depiction of the function of aggrecan in articular cartilage. In the relaxed state, the aggregates draw water into cartilage. With compressive loads, the water is displaced to cushion the load. Upon removal of the load, the water content is restored.
Incorrect Answers:

Question 15

The orthosis shown in Figure 47 is commonly used for

Explanation

DISCUSSION: The orthosis shown is a carbon reinforced Morton’s extension, and it is commonly used for hallux rigidus. It decreases motion of the first metatarsophalangeal joint and subsequently decreases pain.
REFERENCE: Clanton TO: Athletic injuries to the soft tissues of the foot and ankle, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, vol 2, p 1185.

Question 16

Which of the following changes occur in articular cartilage with age?

Explanation

Proteoglycan synthesis decreases with age, as does water content. Cell numbers of cartilage decrease compared to immature cartilage, which has a fairly uniform distribution of abundant cells. A high concentration of chondroitin 4-sulfate has been noted in immature animals, with a fairly rapid diminution in the value noted with aging accompanied by an increase in the concentration of chondroitin 6-sulfate. With advancing age, the total chondroitin sulfate concentrations fall and that of keratin sulfate increases until approximately age 30, where it levels off.

Question 17

A 19-year-old man who plays college volleyball undergoes a routine preparticipation physical examination. Figure 35 shows a posterior view of his dominant shoulder. An electromyogram shows that this is a chronic injury, and an MRI scan shows no abnormalities. The best course of action should be

Explanation

DISCUSSION: Isolated palsy of the infraspinatus portion of the suprascapular nerve is common in volleyball players and is seen frequently in the throwing arm of baseball players. The exact cause is not known, but it may be the result of either tethering or traction on the nerve at the spinoglenoid notch. Synovial cysts in the spinoglenoid notch also can be a cause, but the patient’s negative MRI findings rule out that entity. Because many isolated nerve palsies of the infraspinatus branch are asymptomatic, initial management should always be nonsurgical. Surprisingly, many athletes with this injury can participate fully in sports. Surgical treatment with decompression at the notch is unpredictable and generally is indicated only if nonsurgical management fails.
REFERENCES: Ferretti A, Cerullo G, Russo G: Suprascapular neuropathy in volleyball players. J Bone Joint Surg Am 1987;69:260-263.
Martin SD, Warren RF, Martin TL, Kennedy K, O’Brien SJ, Wickiewicz TL: Suprascapular neuropathy: Results of non-operative treatment. J Bone Joint Surg Am 1997;79:1159-1165.

Question 18

What percent of patients initially diagnosed with classic, high-grade osteosarcoma of the extremity have visible evidence of pulmonary metastasis on CT of the chest?

Explanation

DISCUSSION: CT studies show that approximately 10% to 20% of patients with high-grade osteosarcoma have pulmonary metastases at diagnosis. Although not visible on current staging studies, it is believed that up to 80% of patients have micrometastatic disease that requires systemic chemotherapy. Because it is not possible to identify those patients who do not have disseminated micrometastatic disease, most patients are treated presumptively with chemotherapy.
REFERENCES: Kaste SC, Pratt CB, Cain AM, et al: Metastases detected at the time of diagnosis of primary pediatric extremity osteosarcoma at diagnosis: Imaging features. Cancer 1999;86:1602-1608.
Link MP, Goorin AM, Miser AW, et al: The effect of adjuvant chemotherapy on relapse-free survival in patients with osteosarcoma of the extremity. N Engl J Med 1986;314:1600-1606.

Question 19

Ulnohumeral distraction interposition arthroplasty is considered the most appropriate treatment for which of the following patients?

Explanation

DISCUSSION: Distraction interposition arthroplasty is indicated for the treatment of both rheumatoid and posttraumatic arthritis and is reserved for younger patients who are not suitable candidates for total elbow arthroplasty. Although less reliable than prosthetic replacement, distraction interposition arthroplasty is a useful option in the treatment of young, high-demand patients with elbow arthritis. It is rarely indicated in the presence of polyarticular inflammatory arthritis but may be of value in those patients in whom the disease is limited primarily to the elbow. Isolated radiocapitellar arthritis can be successfully treated with radial head resection, although caution should be exercised if there is evidence of instability. Osteoarthritis is best treated with ulnohumeral arthroplasty.
REFERENCES: Cheng SL, Morrey BF: Treatment of the mobile, painful arthritic elbow by distraction interposition arthroplasty. J Bone Joint Surg Br 2000;82:233-238.
Mansat P: Surgical treatment of the rheumatoid elbow. Joint Bone Spine 2001;68:198-210.

Question 20

Which of the following aids in correction of patellar tracking after total knee arthroplasty (TKA)?

Explanation

DISCUSSION: Correct patellofemoral tracking has proven to be a crucial aspect in TKA because a large percent of problems after TKA are related to the patellofemoral articulation. External rotation of the femoral and tibial components has been shown to aid in tracking. Likewise, medialization of the patellar button aids in patellar tracking and prevention of lateral subluxations and dislocations. Attention to the distal femoral cut is critical in maintaining the joint line and preventing patella baja or alta. Tibial sizing, however, is not directly related to patellar tracking after TKA.
REFERENCES: Callaghan JJ, Rosenberg AG, Rubash HE, et al (eds): The Adult Knee. Philadelphia, PA, Lippincott Williams & Wilkins, 2003, pp 1245-1258.
Merkow RL, Soudry M, Insall JN: Patellar dislocation following total knee replacement. J Bone Joint Surg Am 1985;67:1321-1327.

Question 21

A 22-year-old professional baseball catcher has posterior shoulder pain and severe external rotation weakness with the arm in adduction. Radiographs are normal. MRI scans are shown in Figures 15a through 15c. Management should consist of Review Topic

Explanation

The MRI scans reveal a large posterior paralabral cyst associated with a posterior-superior labral tear. The cyst appears as a well-defined, smoothly marginated mass with low signal intensity on T1-weighted MRI scans and with high signal intensity on T2-weighted MRI scans. MRI also reveals changes in the supraspinatus and infraspinatus muscles secondary to denervation, including decreased muscle bulk and fatty infiltration. MRI has the added advantage, compared with other imaging modalities, of detecting intra-articular lesions, such as labral tears, which are frequently associated with ganglion cysts of the shoulder. In this case of a professional baseball player with a space-occupying lesion causing nerve compression with an associated labral tear, the treatment of choice is arthroscopic decompression of the cyst and repair of the tear. Acromioplasty would not address the primary pathology in this patient.

Question 22

In patients without spondylolisthesis or scoliosis undergoing laminectomy for lumbar spinal stenosis, spinal fusion is generally recommended if Review Topic

Explanation

With the notable exception of fusion for degenerative spondylolisthesis and scoliosis, there is a paucity of evidence on the indications for spinal fusion in patients undergoing laminectomy for spinal stenosis. However, it is generally recommended that if the spine is destabilized (for example by removal of one complete facet joint or by an iatrogenic pars fracture), spinal fusion should be considered. Although fusion can be considered for a very long laminectomy, a two-level laminectomy does not represent, by itself, a clear indication for the addition of a spinal fusion. The repair of a dural tear and the use of nicotine by the patient play no role in the determination of whether or not to add fusion to a laminectomy procedure.

Question 23

Figure 19 is the clinical photograph of a 54-year-old man who underwent a total ankle replacement (TAR). Three weeks after surgery he has increasing pain and a deep wound as seen in the photograph. What is the best next step?

Explanation

DISCUSSION
The patient is 3 weeks out from TAR. The wound is erythematous, and the tendon is visible. At 3 weeks this is an acute wound breakdown. The preferred treatment is a return to the operating room, an exchange of the polyethylene because the wound appears deep enough to go down to the joint, and a flap for coverage. Removal of the total ankle and placement of an antibiotic spacer should be considered in the settings of subacute (6 weeks postop) or chronic infection following TAR. A below-the-knee amputation may be considered with a failed salvage or a chronically infected TAR. Conversion to a fusion may be considered in situations in which the wound bed is not infected. In this case, there is concern for ongoing active infection, and an intercalary allograft is not appropriate.
RECOMMENDED READINGS
Cho EH, Garcia R, Pien I, Thomas S, Levin LS, Hollenbeck ST. An algorithmic approach for managing orthopaedic surgical wounds of the foot and ankle. Clin Orthop Relat Res. 2014 Jun;472(6):1921-9. doi: 10.1007/s11999-014-3536-7. Epub 2014 Feb 28. PubMed PMID:

Question 24

What radiographic view will best reveal degeneration of the pisotriquetral joint in a patient who is being evaluated for pisotriquetral arthrosis?

Explanation

DISCUSSION: The pisotriquetral joint is best seen on a lateral view in 30 degrees of supination. The carpal tunnel view provides visualization of the joint but to a lesser extent. The other views do not provide clear and accurate visualization.
REFERENCES: Paley D, McMurty RY, Cruickshank B: Pathologic conditions of the pisiform and pisotriquetral joint. J Hand Surg Am 1987;12:110-119.
Steinmann SP, Linsheid RL: Pisotriquetral loose bodies. J Hand Surg 1997;22:918-921.
related link ortho mcqs bank

Question 25

Which of the following is considered the lowest level that a standard thoracolumbosacral orthosis (TLSO) can immobilize?

Explanation

DISCUSSION: Without more distal immobilization such as a thigh extension, the lower two lumbar segments generally show the same or even increased mobility with a TLSO.
REFERENCES: White AA, Panjabi MM: Clinical Biomechanics of the Spine, ed 2. Philadelphia, PA, JB Lippincott, 1990, pp 475-509.
Norton PL, Brown T: The immobilizing efficiency of back braces. J Bone Joint Surg Am 1957;39:111-139.

Question 26

Figures 43a and 43b show the T 1 - and T 2 -weighted MRI scans of a 78-year-old woman who reports the sudden atraumatic onset of well-localized medial knee pain. Pain is worse at night and also occurs with weight-bearing activity. What is the most likely diagnosis?

Explanation

DISCUSSION: Osteonecrosis of the tibial plateau occurs infrequently. The symptoms are similar to those of idiopathic osteonecrosis of the medial femoral condyle and include pain and tenderness of the medial aspect of the knee and a slight synovitis. The range of motion of the knee remains within normal limits, and no gross deformity is present. Osteonecrosis of the tibial plateau is easily misdiagnosed as degenerative meniscus or osteoarthritis of the compartment of the knee. Review of lateral radiographs may reveal an osteopenic area in the subchondral bone of the medial tibial plateau. The diagnosis is more easily established with a bone scan where increased uptake of radionucleides is shown over the medial tibial plateau. In osteoarthritic involvement of the medial compartment, uptake is over both the medial femoral condyle and the medial tibial plateau, whereas if osteoarthritis involves the entire knee, uptake is diffuse over the entire joint. Radiographic findings in complex regional pain syndrome are normal as opposed to the findings for osteonecrosis or osteoarthritis. Osteosarcoma has a characteristic radiographic appearance of a bone-forming tumor. Loose bodies can derive from osteochondral fractures; a history of trauma is usually elicited. Osteoarthritis usually presents with joint space narrowing accompanying the weight-bearing pain.
REFERENCES: Soucacos PN, Berris AE, Xenakis TH, et al: Knee osteonecrosis: Distinguishing features in differential diagnosis, in Urbanik JR, Jones JD (eds): Osteonecrosis. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 413-424.
Ecker ML, Lotke PA: Osteonecrosis of the medial part of the tibial plateau. J Bone Joint Surg Am 1995;77:596-601.

Question 27

Figure 62a and Figure 62b

Explanation

DISCUSSION
Figure 58 reveals a posttraumatic valgus deformity. Correction of valgus with lateral soft-tissue release places tension on the peroneal nerve, resulting in an increased risk for nerve palsy. Figures 59a (lateral view) and 59b (Merchant view) illustrate juvenile rheumatoid arthritis with tibiofibular fusion and lateral patellar dislocation. Chronic patellar dislocation is associated with contracture of the lateral retinacular soft tissues and increased risk for patellar subluxation or dislocation after TKA. Extensor mechanism realignment, possibly including tibial tubercle osteotomy and/or proximal soft-tissue realignment, may be required during TKA to centralize the extensor mechanism. Figures 60a (anteroposterior [AP] view) and 60b (lateral view) reveal a fused knee in full extension.
TKA after fusion is associated with multiple complications including skin necrosis, infection, and instability. The skin is contracted because of limited knee motion and has multiple scars (Figure 60c). Mobilization of the skin during and after knee arthroplasty can place excess tension on the soft tissues, resulting in skin necrosis and infection. Treatment consisting of prompt debridement and soft-tissue coverage, usually with medial gastrocnemius muscle transposition, is required. Figure 61 shows a knee with prior tibial tubercle fixation and marked patella infera. Shortening of the patellar ligament is associated with restricted knee motion. This may necessitate more extensile exposure using tibial tubercle osteotomy or rectus snip during TKA to obtain adequate surgical exposure. The inferior position of the patella can cause impingement between the patellar component and tibial insert, resulting in anterior knee pain. Restoring a more normal position of the patella may necessitate distal positioning of the femoral component as well as tibial tubercle osteotomy with proximal recession of the osteotomized tibial tubercle. Figures 62a (AP view of the distal femur) and 62b (AP view of the proximal femur) show a posttraumatic deformity with a large retained intramedullary rod. There is a varus distal femoral deformity that is not severe enough to necessitate extra-articular corrective osteotomy. However, intramedullary hardware precludes use of conventional intramedullary instrumentation, so computer navigation or patient-specific cutting guides will be necessary to orient the bone cuts and avoid implant malalignment.

Question 28

Figure 18 is the radiograph of a 52-year-old woman who has leg length inequality and chronic activity-related buttock discomfort. This has been a life-long problem, but it is getting worse and increasingly causing back pain. What is the best current technique for total hip arthroplasty?

Explanation

DISCUSSION
A high hip center is not recommended for Crowe IV hips because of the lack of acetabular bone and altered hip biomechanics. An anatomic center is a better option but necessitates a technique to address the tight soft-tissue envelope. A trochanteric osteotomy with progressive femoral shortening has been described but can be prone to trochanter nonunion. Iliofemoral lengthening prior to surgery has been described but may not be tolerated by all patients. A shortening subtrochanteric osteotomy avoids trochanter nonunion and allows adjustment of femoral anteversion. Fixation of the osteotomy can include a stem with distal rotational control, plate fixation, a step vs. oblique cut, or strut grafts.

Question 29

A clinical trial is underway for patients with wrist extensor tendinitis. One group of 100 patients are treated with short arm casting. Another group of 100 patients are treated with physical therapy. During analysis of the results, it becomes apparent that 30 patients in the physical therapy group did not complete the full course of physical therapy. Despite not completing a full course of physical therapy, these 30 patients were included in the physical therapy group for analysis. This analysis is an example of which of the following?

Explanation

The following is an example of intent-to-treat analysis.
The intent-to-treat approach aims to keep similar groups similar by not allowing for patient selection based on post-randomization outcomes (including failure to comply with the protocol). This type of analysis ensures the power of randomization so that important unknown variables that impact outcome are likely to be dispersed equally in each comparison group. Conversely, a per-protocol comparison in a clinical trial excludes patients who were not compliant with the protocol guidelines.
Berger et al., in a Level 5 review, discuss many of the principles beyond randomization that are critical for preserving the comparability of the different groups. They report that masking, allocation concealment, restrictions on the randomization, adjustment for prognostic variables, and the intent-to-treat approach to data analysis are important features of designing a good clinical trial.
Incorrect Answers:

Question 30

A 45-year-old man has persistent hindfoot pain that is aggravated by weight-bearing activities. History reveals that he sustained a calcaneus fracture 2 years ago, and he underwent a subtalar fusion 1 year ago. Examination reveals tenderness in the sinus tarsi and across the transverse tarsal joint. A plain radiograph and a CT scan are shown in Figures 24a and 24b. A technetium Tc 99m bone scan reveals uptake at the subtalar joint and at the transverse tarsal joints. Management should now consist of

Explanation

DISCUSSION: The patient has a nonunion at the subtalar joint because of poor preparation of the arthrodesis site with incomplete removal of the articular cartilage. Clinically, he has arthritis at the transverse tarsal joint. Casting with a bone stimulator is not expected to result in a union of the subtalar arthrodesis. To address both the subtalar nonunion and the transverse tarsal joint arthritis, revision of the subtalar arthrodesis and conversion to a triple arthrodesis is the preferred option.
REFERENCES: Graves SC, Mann RA, Graves KO: Triple arthrodesis in older adults: Results after long-term follow-up. J Bone Joint Surg Am 1993;75:355-362.
Haddad SL, Myerson MS, Pell RF IV, Schon LC: Clinical and radiographic outcome of revision surgery for failed triple arthrodesis. Foot Ankle Int 1997;18:489-499.
Sangeorzan BJ, Smith D, Veith R, Hansen ST Jr: Triple arthrodesis using internal fixation in treatment of adult foot disorders. Clin Orthop 1993;294:299-307.
Sangeorzan BJ: Salvage procedures for calcaneus fractures. Instr Course Lect 1997;46:339-346.
Wapner KL: Triple arthrodesis in adults. J Am Acad Orthop Surg 1998;6:188-196.

Question 31

A 36-year-old nurse has had redness, pain, and small vesicles on the pulp of her middle finger for the past 3 days. Management should consist of

Explanation

DISCUSSION: Small vesicles on the fingers of a health care worker suggest a herpetic infection, and the management of choice is observation. Incision and drainage may result in a bacterial infection. Marsupialization is used in the treatment of a chronic paronychia. Calcium gluconate is used for hydrofluoric acid burns, and copper sulfate is used for white phosphorus burns.
REFERENCES: Fowler JR: Viral Infections. Hand Clin 1989;5:613-627.
Jebsen PL: Infections of the fingertip: Paronychias and felons. Hand Clin 1998;14:547-555.

Question 32

A 58-year-old man with insulin-dependent diabetes mellitus underwent primary total knee arthroplasty (TKA). A full-thickness skin slough measuring 3 cm by 4 cm developed, with postsurgical exposure of the patellar tendon. No change is observed in the appearance of the wound after 2 weeks of wet-to-dry dressing changes. What is the best next treatment step for the soft-tissue defect?

Explanation

DISCUSSION:
If wound healing does not occur and deep soft tissues such as the patellar tendon are exposed following TKA, local rotational flap is the procedure of choice. The procedure should be performed relatively early after the recognition of a soft-tissue wound-healing problem. In the setting of TKA, the gastrocnemius muscle is an excellent source of flaps for wound coverage of the proximal tibia.

Question 33

What gene is expressed the earliest during the differentiation of a chondrocyte during endochondral ossification?

Explanation

DISCUSSION: Transcription factors regulate the activation or repression of cartilage-specific genes. Sox-9, considered a major regulator of chondrogenesis, regulates several cartilage-specific genes during endochondral ossification, including collagen types II, IV, and XI and aggrecan.
REFERENCES: Li J, Sandell LJ: Transcriptional regulation of cartilage-specific genes, in Rosier RN, Evans C (eds): Molecular Biology in Orthoapedics, Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 21-24.
Sandell LJ: Genes and gene expression. Clin Orthop 2000;379:S9-S16.

Question 34

A 35-year-old construction worker has developed isolated lateral compartment arthritis. He has lost 50 pounds, now has a body mass index of 30, and still has pain that limits his activities of daily living and work despite receiving a 4-month course of nonsteroidal anti-inflammatory medications and 2 intra-articular cortisone injections. His range of motion is 5 to 110 degrees, and his mechanical axis is 18 degrees of valgus. What is the most appropriate surgical treatment for this patient?

Explanation

DISCUSSION
Knee arthritis in a young laborer is challenging to address. A surgeon could perform an arthroplasty, but there is concern for early failure and the subsequent need for multiple revisions during this patient’s lifespan. Indications for distal femoral varus osteotomy include at least a 12- to 15-degree valgus mechanical axis and range of motion of at least 15 to 90 degrees. Contraindications for this procedure include inflammatory arthritis and restricted knee motion.
RESPONSES FOR QUESTIONS 138 THROUGH 141
Acute periprosthetic infection
Chronic periprosthetic infection
Joint dislocation
Periprosthetic fracture
Pseudotumor
Femoral nerve palsy
Sciatic nerve palsy
Aseptic prosthetic loosening
Select the total hip arthroplasty (THA) complication listed above that most commonly is associated with the clinical scenario described below.

Question 35

A 27-year-old man has neck pain after being involved in a motor vehicle accident. A lateral cervical radiograph is shown in Figure 21. What would be the most common neurologic finding?

Explanation

DISCUSSION: The radiographic findings are consistent with a type II Hangman’s fracture or traumatic spondylolisthesis of C2. This occurs with more than 3 mm of displacement according to the classification of Levine and Edwards. Even though the radiograph reveals significant displacement, the overall space available for the neural elements is increased, therefore minimizing the risk of neural compromise. Neurologic injury is most frequently encountered in type III injuries that are associated with bilateral facet dislocations of C2 on C3 but is infrequent in type I (less than 3 mm displacement) and type II traumatic spondylolisthesis. When neurologic deficits are associated with type II injuries, it is usually the result of an associated head injury. Cruciate paralysis occurs as a result of the crossover of the motor and sensory tracts at different levels of the cord at the C1-C2 junction. This results in normal sensation but complete loss of motor function.
REFERENCES: Levine AM: Traumatic spondylolisthesis of the axis (Hangman’s fracture), in Levine AM, Eismont FJ, Garfin S, Zigler JE (eds): Spine Trauma. Philadelphia, PA, WB Saunders, 1998, pp 287-288.
Francis WR, Fielding JW, Hawkins RJ, Pepin J, Hensinger R: Traumatic spondylolisthesis of the axis. J Bone Joint Surg Br 1981;63:313-318.

Question 36

A 3-year-old child sustains a T2/T3 fracture-dislocation with complete paraplegia secondary to a car accident in which the child was an unrestrained passenger. What is the likelihood that this child will develop subsequent spinal deformity in the future?

Explanation

DISCUSSION: More than than 90% of preadolescent children who sustain a significant spinal cord injury subsequently develop scoliosis. Conversely, progressive paralytic spinal deformity is uncommon in the postadolescent patient. Bracing has not been shown to be effective in the prevention of scoliosis in the preadolescent patient with spinal cord injury.
REFERENCES: Mayfield JK, Erkkila JC, Winter RB: Spine deformity subsequent to acquired childhood spinal cord injury. J Bone Joint Surg Am 1981;63:1401-1411.
Dearolf WW III, Betz RR. Vogl LC, et al: Scoliosis in pediatric spinal cord-injured patients. J Pediatr Orthop 1990;10:214-218.
Mehta S, Betz RR. Mulcahey MJ, et al: Effect of bracing on paralytic scoliosis secondary to spinal cord injury. J Spinal Cord Med 2004;27:S88-S92.

Question 37

-Four months after injury, the tibia is showing evidence of slow healing on radiographs. What is the optimal treatment for this potential nonunion?

Explanation

DISCUSSION FOR QUESTIONS 108 THROUGH 110:
This patient is unstable and is not a good candidate for Early Total Care (ETC) and therefore should be managed by the tenets of Damage Control Orthopaedics (DCO). Débridement and external fixation is preferable for this patient. Intramedullary nails would be a component of ETC. Calcaneal traction is not considered ideal because it does not allow the patient to travel as easily. The S.P.R.I.N.T. study concluded that while reamed nails may offer benefit in closed fractures, there was no difference between reamed or unreamed nails in the treatment of open fractures of the tibia. Uniplanar external fixation and tibial plating are not considered the best options for open tibia fractures. Additional findings of the S.P.R.I.N.T. study conclude that delaying surgical intervention for at least 6 months after injury may reduce the need for reoperation.

Question 38

Accurate evaluation of the upper portion of the subscapularis muscle is best accomplished with active internal rotation

Explanation

DISCUSSION: Internal rotators of the shoulder include the subscapularis, pectoralis major, teres major, and latissimus dorsi muscles. The subscapularis has two portions, with the upper portion receiving its innervation from the upper subscapular nerve (C5) and the lower portion from the lower subscapular nerve (C5-6). The two tests commonly performed to isolate the internal rotation to the subscapularis muscle are the lift-off test and the belly press test. Electromyographic findings have shown the lift-off test to be more accurate for the lower portion of the subscapularis and the belly press test to be more sensitive for the upper portion.
REFERENCES: Hintermeister RA, Lange GW, Schultheis JM, Bey MJ, Hawkins RJ: Electromyographic activity and applied load during shoulder rehabilitation exercises using elastic resistance. Am J Sports Med 1998;26:210-220.
Greis PE, Kuhn JE, Schultheis J, Hintermeister R, Hawkins R: Validation of the lift-off test and analysis of subscapularis activity during maximal internal rotation. Am J Sports Med 1996;24:589-593.

Question 39

Figure 29 shows the radiograph of a 25-year-old woman who has had a 3-month history of ankle pain after sustaining an inversion injury to the ankle. She reports occasional catching, but no sense of instability. Examination reveals ligament stability. Management should consist of

Explanation

DISCUSSION: Osteochondral lesions of the talar dome can have a traumatic or nontraumatic etiology. Most authors site a probable traumatic etiology for lateral lesions. Stage I and II lesions, which are composed of compressed subchondral bone or a partial detached osteochondral fragment, can be treated initially in a non-weight-bearing short leg cast for 6 weeks. Stage III medial lesions can also be treated in the same manner. If symptoms persist, the treament of choice is debridement of the fracture, curettage of the lesion, and drilling of the subchondral bone. This treatment also applies to lateral stage III and all stage IV lesions. If the fragment is at least one third of the size of the talar dome, management should consist of open reduction and internal fixation. In patients with more chronic lesions (4 to 6 months of persistent pain), the threshold to proceed with surgery is lower, even in a stage II lesion.
REFERENCES: Lutter LD, Mizel MS, Pfeffer GB (eds): Orthopaedic Knowledge Update: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 205-226.
Pettine KA, Morrey BF: Osteochondral fractures of the talus: A long-term follow-up. J Bone Joint Surg Br 1987;69:89-92.

Question 40

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 41

What factor is associated with the highest risk for in-hospital complications for patients undergoing a lumbar fusion for degenerative spondylolisthesis? Review Topic

Explanation

Age and having three or more comorbidities is associated with a higher rate of complications in patients undergoing a lumbar fusion for lumbar degenerative spondylolisthesis. Race, gender, and hospital size have not been found to be associated with higher complication rates.

Question 42

Treatment of a cruciate-retaining total knee that is unstable in flexion is best accomplished by

Explanation

DISCUSSION: Pagnano and associates revised 25 painful primary posterior cruciate-retaining total knee arthroplasties for flexion instability. The patients shared typical clinical presentations that included a sense of instability without frank giving way, recurrent knee joint effusion, soft-tissue tenderness involving the pes anserine tendons and the retinacular tissue, posterior instability of 2+ or 3+ with a posterior drawer or a posterior sag sign at 90° of flexion, and above-average motion of the total knee arthroplasty. Twenty-two of the knee replacements were revised to posterior stabilized implants, and three underwent tibial polyethylene liner exchange only. Nineteen of the 22 knee replacements revised to a posterior stabilized implant showed marked improvement after the revision surgery. Only one of the three knee replacements that underwent tibial polyethylene exchange was improved. Flexion instability can be a cause of persistent pain and functional impairment after posterior cruciate-retaining total knee arthroplasty. Revision surgery that focuses on balancing the flexion and extension spaces, in conjunction with a posterior stabilized knee implant, seems to be a reliable treatment for symptomatic flexion instability after posterior cruciate-retaining total knee arthroplasty.
REFERENCE: Pagnano MW, Hanssen AD, Lewallen DG, Stuart MJ: Flexion instability after primary posterior cruciate-retaining total knee arthroplasty. Clin Orthop 1998;356:39-46.

Question 43

A 33-year old man sustains a posterior elbow dislocation after a fall. Attempts at closed reduction result in recurrent instability. What is the most common ligamentous injury found at the time of surgical stabilization?

Explanation

Classic posterior elbow dislocations result from a posterolateral rotatory mechanism, whereby the hand is fixed (typically on the ground) while the weight of the body creates a valgus and external rotation moment on the elbow. This results first in tearing of the lateral collateral ligament that proceeds medially through the anterior and posterior joint capsules, ending with potential involvement of the ulnar collateral ligament (but this is not universal). McKee and associates assessed the lateral soft-tissue injury pattern of elbow dislocations
with and without associated fractures at the time of surgery. Injury to the lateral collateral ligament complex was seen in every case, with avulsion from the distal humerus as the most common finding. Midsubstance
tears, proximal avulsions, and distal bony avulsions of the ulnar collateral ligament are less common.

Question 44

Pain associated with a proximal medial tibial osteochondroma in a 10-year-old patient is most commonly the result of

Explanation

DISCUSSION: Pain secondary to an osteochondroma is usually from soft-tissue irritation and bursal formation. This is particularly common for proximal medial tibia osteochondromas that irritate the pes anserine tendons. Malignant degeneration into a chondrosarcoma rarely occurs, is usually associated with multiple hereditary exostoses, and usually occurs after skeletal maturity.
REFERENCES: Borges AM, Huvos AG, Smith J: Bursa formation and synovial chondrometaplasia associated with osteochondromas. Am J Clin Pathol 1981;75:648-653.
Hudson TM, Springfield DS, Spanier SS, Enneking WF, Hamlin DJ: Benign exostoses and exostotic chondrosarcomas: Evaluation of cartilage thickness by CT. Radiology 1984;152:595-599.

Question 45

A 16-year-old boy has had knee pain for the past 6 months, and activity restrictions have not provided relief. An MRI scan reveals a stable 1.5 cm by 1 cm osteochondritis dissecans on the weight-bearing surface of the lateral femoral condyle. What is the best course of treatment? Review Topic

Explanation

As a child approaches skeletal maturity, osteochondritis dissecans lesions are unlikely to heal with continued nonsurgical management. Drilling of the lesion has a high success rate. The lesion is stable and an open repair or osteochondral transplant is not needed.

Question 46

A 51-year-old woman with no preoperative neurologic deficit is undergoing elective anterior cervical diskectomy and fusion (ACDF) with plating and fusion for a C5-6 disk herniation with right-sided neck pain. Thirty minutes into the surgery the neurophysiologic monitoring shows a rapid drop and then loss of amplitude in the right cortical somatosensory-evoked potential waveform. All other waveforms remained normal and unchanged, including right-sided cervical (subcortical) and peripheral (Erb’s point), and those from the left-sided upper extremity and both lower extremities. What is the most likely cause of the change?

Explanation

DISCUSSION: The change noted is focal and confined to the cortex, sparing the opposite side, both lower extremities, and the subcortical waveforms, making all the choices unlikely with the exception of carotid compression with focal cortical ischemia. This may be associated with poor collateral flow from the opposite hemisphere due to an incomplete circle of Willis.
REFERENCES: Drummond JC, Englander RN, Gallo CJ: Cerebral ischemia as an apparent complication of anterior cervical discectomy in a patient with an incomplete circle of Willis. Anesth Analg 2006;102:896-899.
Yeh YC, Sun WZ, Lin CP, et al: Prolonged retraction on the normal common carotid artery induced lethal stroke after cervical spine surgery. Spine 2004;29:E431-E434.

Question 47

A 48-year-old man reports localized plantar forefoot pain. Examination reveals a discrete callus (intractable plantar keratosis) with well-localized tenderness beneath the second metatarsal head. The callus most likely lies beneath what structure?

Explanation

DISCUSSION: A discrete or focal callus is a response to excessive weight-bearing stress beneath the lateral (fibular) condyle of a lesser metatarsal head (most commonly second). The other structures generally have not been associated with a discrete callus.
REFERENCES: Coughlin MJ, Mann RA: Keratotic disorders of the plantar skin, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, Mosby-Year Book, 1993, pp 413-465.
Cracchiolo A: Surgical procedures of the lateral metatarsals, in Jahss MH (ed): Disorders of the Foot and Ankle, ed 2. Philadelphia, PA, WB Saunders, 1991, pp 1269-1283.

Question 48

A 28-year-old man sustained a shoulder dislocation 2 years ago. It remained dislocated for 3 weeks and required an open reduction. He now reports constant pain and has only 60 degrees of forward elevation and 10 degrees of external rotation. He desires to return to some sporting activities. An AP radiograph and intraoperative photograph (a view of the humeral head through a deltopectoral approach) are shown in Figures 31a and 31b. What is the best treatment option to decrease pain and improve function? Review Topic

Explanation

The radiograph and intraoperative photograph show osteonecrosis with near complete head loss/collapse. A stemmed implant is more appropriate in this patient because there is very little bone to support a resurfacing implant. In a younger patient, a glenoid implant should be delayed as long as possible because of the eventual need for revision secondary to glenoid loosening and wear, especially in a young active male. The hemiarthroplasty may be converted to a total shoulder arthroplasty in the future.

Question 49

A 28-year-old man has had a 2-week history of right posterior leg pain, with numbness and tingling in the same distribution. He denies any problems with bowel or bladder function. Examination shows intact motor strength in his bilateral lower extremities, with numbness to light touch in the lateral border of his right foot. Over the past 2 weeks, his leg pain has improved significantly. MRI scans are shown in Figures 57a and 57b. What is the most appropriate course of management? Review Topic

Explanation

MRI of lumbar spine
Repeat ESR/CRP and whole body bone scan
CT of lumbar spine
Dynamic flexion/extension plain film radiographs
Dynamic lateral bending plain film radiographs
This patient has clinical and radiographic features of failed spinal arthrodesis. CT scan have been shown to be the most relable method for assessing spinal fusion postoperatively.
Reported rates of nonunion following posterior spinal fusion range from 0-70%. Rates are variable due to the various operative techniques, underlying diagnoses as well as asymptomatic patients. Non-union may lead to changes in alignment, spinal instability and potential neurological injury. Static radiographs have long been used as a practical method of fusion assessment, but these tend to significantly overestimate the presence of a solid fusion. Lack of movement at a fused segment, on dynamic views, does not confirm fusion. CT offers excellent bony resolution and are less affected by metal artifact compared to MRI.
Patel et al. showed that tobacco use, malnutrition, oral anti-inflammatory use, multilevel fusion, prior spine surgery, and sagittal imbalance are all risk factors for spinal nonunion.
Mok et al. looked at erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels after spinal surgery and compared their usefulness as predictors of infectious complications in the early postoperative period. They found that CRP is more applicable, predictable, and responsive in the early postoperative period compared with ESR. Using a second rise or failure to decrease as expected for CRP is sensitive for infection.
Shelby et al. reviewed the radiological assessment of spinal fusion. They comment that fine-cut imaging, multiplanar reconstruction, and metal artifact reduction have increased the ability to assess fusion on CT.
Figure A shows a series of lateral radiographs of the lumbar spine with posterior spinal instrumentation. Illustration A shows a lateral CT scan image of multi-level pseudoarthrosis after posterior spinal instrumented fusion. Illustration B shows an
intra-operative
view
of
spinal
pseudoarthrosis
(white
arrow).
Incorrect
(SBQ12SP.19) A 41-year-old male presents with acute onset of low back pain that started when he was trying to lift a heavy box while helping his brother move apartments two days ago. The pain has been severe enough to cause him to miss work yesterday. He has no neurologic deficits. What are the chances he will return to work within 6 weeks? Review Topic
1 80 to 90%
2 70 to 80%
3 60 to 70%
4 50 to 60%
5 40 to 50%
Most adults (up to 80%) will experience an episode of low back pain in their lifetime. In those whose pain is severe enough to cause them to miss work, 60 to 70% will return by 6 weeks, and 80 to 90% will return by 12 weeks.
Low back pain is common in adults. Most patients experience resolution of symptoms quickly and have no lasting loss of function. However, 5 to 10% develop chronic pain. Recurrence of pain is common, and is part of the natural history, occurring in 20 to 72% of patients. After 12 weeks, return to work rates are slow.
Shen et al. review the nonoperative management of acute and chronic low back pain. The authors note that none of the available interventions has been proven by high quality large randomized controlled trials. The authors believe that low dose oral
steroids are safe in the short term and that injection therapy should not be used without a reasonable presumptive diagnosis.
Madigan et al. review the management of lumbar degenerative disease. The authors emphasize that the majority of patients improve within 6 weeks with or without treatment. For patients that do not, the authors do not recommend epidural injection, as there are no good studies to support their use in the treatment of discogenic back pain. When surgical treatment is indicated they state that arthrodesis is the gold standard, although the long term results of total disk arthroplasty are being elucidated.
Illustration A shows a table of available non-operative treatment modalities for back pain. Illustration B shows a list of possible diagnoses associated with acute low back pain, with those associated with neurogenic pain italicized. Illustration C shows a list of 'red flag' symptoms indicating serious/emergent causes of low back pain.
Incorrect
2:
Longer
to than
90%

Question 50

Which of the following tumors have characteristic chromosomal translocations?

Explanation

DISCUSSION: Ewing’s sarcoma has an 11;22 translocation that creates the EWS/FLI1 fusion gene, and synovial sarcoma has an X;18 translocation that creates the STT/SSX fusion gene. The other tumors do not have consistent translocations.
REFERENCES: Sandberg AA: Cytogenetics and molecular genetics of bone and soft-tissue tumors. Am J Med Genet 2002;115:189-193.
Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 11-20.

Question 51

A 13-year-old baseball pitcher presents with worsening medial-sided elbow pain. He pitches 7 months out of the year, throws 85 pitches per game and plays in two games per week. His fastball speed is approximately 75mph. He regularly plays outfield once he has been relieved of pitching. Which of the following is most likely contributing to his elbow pain? Review Topic

Explanation

Young athletes who throw greater than 80 pitches per game have an increased risk of shoulder and elbow injury. For a 13-year-old, the recommended maximum number of pitches per game is 75.
Little League elbow is a medial-sided overuse injury that occurs in the skeletally immature athlete. During execution of the baseball pitch, tremendous valgus and extension stresses occur at the elbow. Repetitive microtrauma can ultimately injure the medial epicondyle apophysis, ulnar collateral ligament or the flexor-pronator muscle mass. Limiting the number of pitches and innings played per game, as well as the number of months of competitive pitching per year, has been recommended to prevent these overuse injuries in the young athlete.
Olsen et al performed a case control study to determine risk factors associated with the development of shoulder and elbow injuries in adolescent baseball pitchers. Greater than 8 months of competitive pitching per year, more than 80 pitches per game and a fastball speed of greater than 85mph were all associated with increased risk of injury. Continued pitching despite arm fatigue and pain, being a starting pitcher, greater number of warm-up pitches, participating in showcases and regular use of NSAIDs were also associated with injury. The type of pitch (fastball, changeups and breaking balls) and continued play in a different position once being relieved was not associated with increased risk of injury.
Andrews et al authored a review article on ulnar collateral ligament injuries in throwing athletes. According to the USA Baseball Medical/Safety Advisory Committee, young baseball pitchers should avoid breaking pitches, such as curveballs and sliders, and avoid year-round baseball. A minimum of 3 months of complete rest from pitching per year is vital. Youth pitching coaches should be educated to ensure proper pitching mechanics are being reinforced.
Illustration A is a table depicting the recommended maximum number of pitches by age group.
Incorrect Answers:

Question 52

A corset-type brace may help reduce symptoms during an episode of acute low back pain as the result of

Explanation

DISCUSSION: Although there is no significant alteration in motion with a corset, studies have shown a decrease in intradiskal pressure.
REFERENCES: Nachemson A, Morris JM: In vivo measurements of intradiscal pressure: Discometry, a method for determination of pressure in the low lumbar disc. J Bone Joint Surg Am 1964;46:1077-1092.
Axelsson P, Johnsson R, Stromqvist B: Effect of lumbar orthosis on intervertebral mobility: A roentgen stereophotogrammetric analysis. Spine 1992;17:678-681.

Question 53

A 35-year-old woman undergoes an L4-5 anterior fusion via a left retroperitoneal approach. Postoperative examination reveals that her right foot is cool and pale. Her neurologic examination is normal, and her pedal pulses are asymmetric. What is the most likely reason for the right foot finding?

Explanation

DISCUSSION: The lower extremity symptoms are consistent with a sympathectomy that is the result of an injury to the sympathetic chain, ipsilateral to the approach along the anterior border of the lumbar spine. This results in a warm, red foot, which creates the appearance that the normal cooler foot may have compromised circulation. The latter generally attracts greater attention because of the risks associated with limb ischemia. The condition usually is self-limited and does not require any specific treatment.
REFERENCES: Rothman RH, Simeone FA (eds): The Spine, ed 4. Philadelphia PA, WB Saunders, 1999, p1550.
Benzel EC (ed): Spine Surgery Techniques, Complication Avoidance and Management. New York, NY, Churchill Livingstone, 1999, p 190.

Question 54

A 47-year-old man with Charcot-Marie-Tooth (CMT) disease was treated with a fifth metatarsal head resection for a symptomatic bunionette 2 years ago. What is the most likely complication seen at this time?

Explanation

DISCUSSION: CMT is characterized by a cavovarus foot position that increases weight-bearing stresses along the lateral border. Removal of the fifth metatarsal head carries the risk of creating a transfer lesion at the fourth metatarsal head, particularly with a cavovarus foot. Claw toes are common in CMT, but the fifth toe would be flail in this situation. Ulceration is unlikely given the lack of underlying bone. Peroneal atrophy is associated with CMT but would not be a complication of this procedure. Charcot arthropathy is a neuropathic process frequently seen in individuals with diabetes mellitus.
REFERENCES: Kitaoka HB, Holiday AD Jr: Metatarsal head resection for bunionette: Long-term followup. Foot Ankle 1991;11:345-349.
Coughlin MJ, Mann RA, Saltzman CL: Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby, 2007, pp 1312-1315.

Question 55

What significant structure is most at risk during a posterior approach of the Achilles tendon near its musculotendinous junction?

Explanation

DISCUSSION: The sural nerve crosses near the midline at the level of the musculotendinous junction before descending to its more lateral location distally. The saphenous nerve and vein are further medial and at less risk. The posterior tibial nerve is at risk only during deep dissection, such as harvesting flexor hallucis longus tendon graft. The plantaris muscle lies in this area but is of little clinical significance.
REFERENCES: Webb J, Moorjani N, Radford M: Anatomy of the sural nerve and its relation to the Achilles tendon. Foot Ankle Int 2000;21:475-477.
Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 101-111.

Question 56

The main advantage of surgical repair of an acute Achilles tendon rupture, when compared with nonsurgical management, is reduced

Explanation

DISCUSSION: The literature supports similar clinical outcomes after surgical and nonsurgical methods. The chief difference lies in the complications between the groups. Surgical patients experience more wound problems but a significantly lower rerupture rate. Although suturing the tendon allows earlier mobility, the tendon healing time is unchanged. Nonsurgical methods are less expensive to provide.
REFERENCES: Maffulli N: Rupture of the Achilles tendon. J Bone Joint Surg Am 1999;81:1019-1036.
Cetti R, Christensen SE, Ejsted R, Jensen NM, Jorgensen U: Operative versus nonoperative treatment of Achilles tendon rupture: A prospective randomized study and review of the literature. Am J Sports Med 1993;21:791-799.
Nistor L: Surgical and non-surgical treatment of Achilles tendon rupture. J Bone Joint Surg Am 1981;63:394-399.

Question 57

The most appropriate next surgical procedure is

Explanation

DISCUSSION
This patient’s arthritis likely has progressed to the lateral compartment. The location and degree of local pain and tenderness are the most important physical findings. History and physical findings indicate arthritis progression to the lateral and anterior compartments. This scenario suggests the need for conversion of the unicompartmental arthroplasty to TKA.

Question 58

A football lineman who sustained a traumatic injury while blocking during a game now reports that his shoulder is slipping while pass blocking. Examination reveals no apprehension in abduction and external rotation; however, he reports pain with posterior translation of the shoulder. He has full strength in external rotation, internal rotation, and supraspinatus testing. What is the pathology most likely responsible for his symptoms?

Explanation

DISCUSSION: Traumatic posterior instability is a common finding in football players, especially in the blocking positions as well as in the defensive linemen and linebackers.

A traumatic blow to the outstretched arm results in posterior glenohumeral forces. Labral detachment at the glenoid rim is common. Patients report slipping or pain with posteriorly directed pressure. Rarely do these patients have true dislocations that require reduction; however, recurrent episodes of subluxation or pain are not uncommon. Posterior repair has

been shown to be successful in the treatment of traumatic instability.
REFERENCES: Bottoni CR, Franks BR, Moore JH, et al: Operative stabilization of posterior shoulder instability. Am J Sports Med 2005;33:996-1002.
Williams RJ III, Strickland S, Cohen M, et al: Arthroscopic repair for traumatic posterior shoulder instability. Am J Sports Med 2003;31:203-209.
Kim SH, Ha KI, Park JH, et al: Arthroscopic posterior labral repair and capsular shift for traumatic unidirectional recurrent posterior subluxation of the shoulder. J Bone Joint Surg Am 2003;85:1479-1487.

Question 59

In what decade does the peak incidence of conventional osteosarcoma occur?

Explanation

DISCUSSION: Conventional osteosarcoma most frequently occurs in the second decade, followed by the third decade. Approximately 70% to 75% of patients with osteosarcoma are between the ages of 10 and 25 years. Secondary osteosarcoma (arising in Paget’s disease or radiation-induced) is seen in older adults.
REFERENCES: Simon MA, Springfield DS, et al: Osteogenic Sarcoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 266.
Mirra JM: Bone Tumors: Clinical, Radiologic, and Pathologic Correlations. Philadelphia, PA, Lea and Febiger, 1989.
Wold L, et al: Osteogenic sarcoma: Atlas of Orthopaedic Pathology. Philadelphia, PA, WB Saunders, 1990, p 14.

Question 60

A 32-year-old man sustained a closed injury after falling 25 feet from a roof. His ankle and foot are severely swollen. Radiographs and CT scans are shown in Figures 29a through 29d. Initial management should consist of

Explanation

DISCUSSION: The patient has a severe high-energy injury from axial loading to the left ankle and distal tibia. This is a closed injury, but the soft tissues are injured and severely swollen. Initial treatment should focus on skeletal stabilization, and incisions directly over the fracture area should be avoided until soft-tissue stabilization has occurred. Immediate spanning external fixation with plans for a delayed reconstruction as needed for the joint surface is the treatment of choice. Closed reduction and application of a constrictive long leg cast may lead to increased risk of tissue necrosis. Immediate open procedures to internally fix the fracture add the risks of soft-tissue necrosis and are to be avoided. Percutaneous plating may be one of the delayed fixation options but should not be used immediately. Primary ankle arthrodesis is not indicated.
REFERENCES: Thordarson DB: Complications after treatment of tibial pilon fractures: Prevention and management strategies. J Am Acad Orthop Surg 2000;8:253-265.
Marsh JL, Bonar S, Nepola JV, DeCoster TA, Hurwitz SR: Use of an articulated external fixator for fractures of the tibial plafond. J Bone Joint Surg Am 1995;77:1498-1509.
Wyrsch B, McFerran MA, McAndrew M, et al: Operative treatment of fractures of the tibial plafond: A randomized, prospective study. J Bone Joint Surg Am 1996;78:1646-1657.

Question 61

A 68-year-old woman stepped on a needle while walking barefoot 10 days ago. She is not certain but thinks it is imbedded in her foot, and she notes local tenderness at the puncture site and drainage. Her primary care physician has been treating her with oral antibiotics. A plain radiograph is shown in Figure 38. What is the best course of action?

Explanation

DISCUSSION: Based on the radiographic findings, the patient has a metallic foreign body in her foot that is consistent with a needle. She has local infection secondary to the continued presence of the foreign body. CT is not necessary to localize the foreign body as it is adequately visualized on the plain radiographs. The infection cannot be adequately treated until the foreign body is removed. Attempted removal of foreign bodies without proper anesthesia and fluoroscopy frequently results in frustration because of the inability to localize the foreign body. Removal in a surgical suite with proper anesthesia and fluoroscopy is the preferred option. Once the foreign body is removed, the local infection will resolve rapidly.
REFERENCES: Combs AH, Kernek CB, Heck DA: Orthopedic grand rounds: Retained wooden foreign body in the foot detected by computed tomography. Orthopedics 1986;9:1434-1435.
Markiewitz AD, Karns DJ, Brooks PJ: Late infections of the foot due to incomplete removal of foreign bodies: A report of two cases. Foot Ankle Int 1994;15:52-55.

Question 62

A 9-year-old boy falls from a scooter and sustains the injury shown in the radiographs in Figure 26. After closed reduction and cast immobilization, what is the most likely complication that can result?

Explanation

DISCUSSION: The radiographs show a fracture of the distal radius and ulna physis. The most likely complication is growth arrest of the distal ulna. In contradistinction to physis fractures of the radius (growth arrest incidence of less than 5%), the incidence of growth arrest in the ulna is between 30% and 40%. Entrapment of the EPL tendon and cross union between the two bones is extremely rare.
REFERENCES: Vanheest A: Wrist deformities after fracture. Hand Clin 2006;22:113-120.
Cannata G, De Maio F, Mancini F, et al: Physeal fractures of the distal radius and ulna: Long-term prognosis. J Orthop Trauma 2003;17:172-179.
Ray TD, Tessler RH, Dell PC: Traumatic ulnar physeal arrest after distal forearm fractures in children. J Pediatr Orthop 1996;16:195-200.
Aminian A, Schoenecker PL: Premature closure of the distal radial physis after fracture of the distal radial metaphysis. J Pediatr Orthop 1995;15:495-498.

Question 63

What three structures are considered the primary constraints necessary for elbow stability?

Explanation

DISCUSSION: The three primary constraints necessary for elbow stability in all directions are the ulnar part of the lateral collateral ligament (also called the lateral ulnar collateral ligament), the anterior band of the medial collateral ligament, and the coronoid. The radial head and capsule are secondary constraints to elbow instability.
REFERENCES: Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 283-294.
Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 345-354.

Question 64

A 50-year-old man undergoes revision total knee arthroplasty (TKA). The tibial component shown in Figure 153 was retrieved at the time of revision. The wear damage demonstrated on the backside of the tibial component is most likely related to which wear mechanism(s)?

Explanation

DISCUSSION
Pitting and delamination seen in tibial component retrievals on the bearing surface of a TKA is related to fatigue wear. Backside wear is shown in the photograph; this is where the lot numbers usually are present, but now they are not distinguishable because of backside wear. This wear mechanism is attributable to adhesive and abrasive wear. The nanometer-size particles created by this wear mechanism account for the higher prevalence of osteolysis associated with modular tibial components.
CLINICAL SITUATION FOR QUESTIONS 154 AND 155
Five weeks ago, an 82-year-old man underwent revision total knee arthroplasty (TKA). Three weeks after surgery he had a dental cleaning. The patient now reports 2 days of worsening pain following a long physical therapy session. His C-reactive protein (CRP) level is 15.0 mg/L (reference range, 0.08-3.1 mg/L). Upon examination, there is no drainage and slight effusion, and he has a passive range of motion to 110 degrees. Radiographs are unremarkable.

Question 65

A 28-year-old woman sustained an injury to her dominant right arm after falling off her porch. Examination reveals a deformity at the elbow. She is neurovascularly intact. Figures 46a and 46b show the radiographs obtained before closed reduction, and postreduction radiographs are shown in Figure 46c and 46d. What is the most likely early complication?

Explanation

DISCUSSION: The patient has a complex fracture-dislocation of the elbow. The radial head is fractured, and there is a displaced coronoid fracture. These associated fractures indicate that the elbow is at high risk for recurrent instability after initial treatment. To prevent this complication, surgical treatment will most likely be required and will consist of some or all of the following: radial head open reduction and internal fixation or replacement, coronoid open reduction and internal fixation, medial and lateral ligament repairs, and even articulated external fixation. This patient was treated with open reduction and internal fixation of the radial head, and the elbow redislocated postoperatively.
REFERENCES: Ring D, Jupiter JB: Reconstruction of posttraumatic elbow instability. Clin Orthop 2000;370:44-56.
O’Driscoll SW: Classification and evaluation of recurrent instability of the elbow. Clin Orthop 2000;370:34-43.
O’Driscoll SW, Morrey BF, Korinek S, An KN: Elbow subluxation and dislocation. Clin Orthop 1992;280:186-197.

Question 66

Delayed-onset muscle soreness (DOMS) is initially evident at the muscle tendon junction and can spread throughout the entire muscle. It is primarily associated with what type of exercise? Review Topic

Explanation

DOMS is primarily associated with eccentric exercise because fiber lengthening occurs during muscle contraction. Muscle injury occurs very early during eccentric exercise, with structural disruption of the cytoskeleton. A significant increase in creatine kinase levels occurs 24 to 48 hours after exercise and may peak between 3 to 6 days after exercise. All other choices are not strongly associated with delayed muscle soreness.

Question 67

What is the most prevalent adverse event associated with allogeneic blood transfusion?

Explanation

DISCUSSION: Clerical error leading to acute hemolysis and even death occurs in 1:12,000 to 1:50,000 transfusions. Bacterial contamination leading to sepsis/shock occurs in 1:1 million transfusions. HIV transmission is approximately 1:500,000 transfusions and hepatitis C is 1:103,000 transfusions. Anaphylactic reactions occur in 1:150,000 transfusions.
REFERENCES: Aubuchon JP, Birkmeyer JD, Busch MP: Safety of the blood supply in the United States: Opportunities and controversies. Ann Intern Med 1997;127:904-909.
Popovsky MA, Whitaker B, Arnold NL: Severe outcomes of allogeneic and autologous blood donation: Frequency and characterization. Transfusion 1995;35:734-737.

Question 68

Which of the following structures are found in the anterior tarsal tunnel?

Explanation

DISCUSSION: The contents of the anterior tarsal tunnel are the extensor hallucis longus, tibialis anterior, extensor digitorum longus, dorsalis pedis artery, and the deep peroneal nerve. The term “anterior tarsal tunnel syndrome” is used to specifically describe the compression of the deep peroneal nerve under the inferior extensor retinaculum. With nerve compression, patients report a burning sensation across the dorsum of the foot with paresthesias in the first web space. There also may be wasting and weakness of the extensor digitorum brevis.
REFERENCES: Kuritz HM: Anterior entrapment syndromes. J Foot Surg 1976;15:143-148.
Sarrafian S: The Anatomy of the Foot and Ankle: Descriptive, Topographic, Functional, ed 2. Philadelphia, PA, JB Lippincott, 1993, pp 113-158.

Question 69

03 A 37 year-old woman with thoracic back pain has had hemoptysis and dyspnea for the past month. A thoracic spine radiograph shows a compression fracture of T-9 and a mass in the right lung. What is the best course of action?

Explanation

Here is an algorithm from OKU 6 Tumors of the Spine pp 723-736

This question gives you the history, skips right over physical exam and goes into plain films. With this patient’s history of hemoptysis and dyspnea and a lung mass, the next steps in this patients work-up would include the competion of initial work-up, metastatic work-up, then pre-operative planning. Goals of treatment are to 1) protect or restore neurologic function, 2) control pain,

Question 70

In a patient with a soft-tissue sarcoma treated by wide excision and radiation therapy, the risk of subsequent fracture is probably most influenced by

Explanation

DISCUSSION: While most pathologic fractures are in the lower extremity in patients treated for soft-tissue sarcomas by wide excision and adjuvant radiation therapy, risk factors for such fractures are bone resection associated with excision of the tumor and soft-tissue sarcomas of the thigh that require periosteal stripping at the time of resection. Such fractures can occur late, often more than 6 months after surgery, are difficult to treat, and often result in nonunion.
REFERENCES: Bell RS, O’Sullivan B, Nguyen C, et al: Fractures following limb-salvage surgery and adjuvant irradation for soft-tissue sarcoma. Clin Orthop 1991;271:265-271.
Lin PP, Boland PJ, Healey JH: Treatment of femoral fractures after irradiation. Clin Orthop 1998;352:168-178.

Question 71

Figure 19 shows the radiograph of a 6-month-old infant who has limited hip motion. History reveals no complications during pregnancy or delivery. Examination reveals that hip abduction is 45 degrees in flexion bilaterally. The neurologic examination is normal. What is the best course of action?

Explanation

DISCUSSION: Diminished hip abduction can occur in normal children and is not always associated with hip pathology; therefore, initial management should consist of observation.
REFERENCE: Castelein RM, Korte J: Limited hip abduction in the infant. J Pediatr Orthop 2001;21:668-670.

Question 72

A 4-year-old boy sustained a nondisplaced, but complete, fracture of the left proximal tibial metaphysis 1 year ago. The fracture healed uneventfully in an anatomic position. Examination of the injured extremity now reveals 18° of valgus compared with 3° of valgus on the opposite side. Management should now include

Explanation

DISCUSSION: The development of a valgus deformity after this type of fracture is a well-known occurrence, and the patient’s parents should be informed about this risk. In a patient who is age 4 years, the natural history is one of gradual correction by the development of a physiologic varus deformity at the distal tibial physis; therefore, no active intervention is needed at this time. Bracing has no effect on the deformity, and the child is too young for any procedure on the growth plate. Proximal tibial osteotomy is reserved until the patient nears skeletal maturity because of the risk of recurrence of the deformity. Lateral stapling can be done near skeletal maturity if the deformity persists, but this is unlikely to be necessary.
REFERENCES: Zionts LE, MacEwen GD: Spontaneous improvement of posttraumatic tibia valga. J Bone Joint Surg Am 1986;68:680-687.
Beaty JH, Kumar A: Fractures about the knee in children. J Bone Joint Surg Am 1994;76:1870-1880.

Question 73

Figure 7 shows a sagittal T 1 -weighted MRI scan. What muscle/tendon is identified by the arrow?

Explanation

DISCUSSION: The sagittal T₁-weighted MRI scan is useful for interpreting the quality of muscle. The arrow is pointing to the teres minor.
REFERENCES: Goutallier D, Postel JM, Gleyze P, et al: Influence of cuff muscle fatty degeneration on anatomic and functional outcomes after simple suture of full-thickness tears.

J Shoulder Elbow Surg 2003;12:550-554.
Agur AM (ed): Grant’s Atlas of Anatomy, ed 9. Baltimore, MD, Lippincott Williams & Wilkins, 1991, p 394.

Question 74

Figure 100 is the MR image of a 19-year-old man who sustains recurrent anterior shoulder dislocations. The lesion shown occupies approximately 10% of the articular surface. What is the most appropriate treatment?

Explanation

DISCUSSION
The MR image shows a bony Bankart lesion involving less than 20% of the glenoid joint surface. One series reported high success rates after arthroscopic treatment when the defect was incorporated into the repair. Anterior bony deficiencies occupying more than 25% to 30% of the glenoid joint surface treated with soft-tissue repair only are associated with high
recurrence rates. In these patients, an open or arthroscopic coracoid transfer or distal tibial allograft reconstruction should be considered. ORIF has been reported for treatment of large acute glenoid rim fractures, but is not recommended for recurrent anterior shoulder instability in the setting of a 10% glenoid rim fracture.

Question 75

A child born with myelomeningocele is expected to be an ambulator with bracing. Examination by the consulting orthopaedic surgeon reveals rigid clubfeet in addition to the neurologic issues. Management should consist of

Explanation

DISCUSSION: In a child with myelomeningocele, the guiding principle of treatment is to achieve a plantigrade foot by the time the child is ready to stand. The standard clubfoot protocol should be followed, but these children will require an aggressive surgical release to obtain a sufficient correction.
REFERENCES: Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 65-78.
Kasser JE (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 503-514.

Question 76

A 13-year-old girl presents with back pain for 6 months. Figures A and B are SPECT scan and CT images taken at the time of presentation. What is the most likely diagnosis? Review Topic

Explanation

This
patient
has
spondylolysis.
Spondylolysis is a common cause of back pain in children/adolescents. It is common in sports with repetitive hyperextension (gymnasts, weightlifters, football linemen). It is best seen on lateral and oblique radiographs, CT (best study to diagnose and delineate anatomy), and SPECT.
Saifuddin et al. reviewed the orientation of the pars fracture. They found that only 32% of defects were oriented within 15° of the 45° lateral oblique plane and would be
visible on oblique radiographs. They thus recommend CT scans for spondylolysis.
Cheung et al. reviewed spondylolysis and spondylolisthesis. They advocate pars repair for symptomatic spondylolysis and low-grade, mobile spondylolisthesis with pars defects cephalad to L5 and for those with multiple-level defects.
Figure A is a 99mTc-MDP SPECT scan showing increased uptake at the right L5 pars interarticularis. Figure B is an axial helical CT image showing bilateral spondylolysis at L5. Illustration A is a corresponding sagittal reconstruction image demonstrating right pars fracture into the right L5 superior facet. Illustration B shows the appearance of osteoblastic metastasis (green arrow). Illustration C shows the options for pars repair.
Incorrect

Question 77

What is the most likely cause of recurrent symptoms following excision of a third web space neuroma?

Explanation

DISCUSSION: When a recurrent neuroma forms at the end of the resected nerve, it does not retract far enough because either the transection was not proximal enough or it is tethered by plantar neural branches. The transverse intermetatarsal ligament may reform, but it is not associated with pathology. Synovial cysts and synovitis are part of the differential diagnosis but are not associated with neuroma excision. Complex regional pain syndrome may result from neuroma excision, but this is rare and the symptoms are different.
REFERENCES: Beskin JL: Recurrent interdigital neuromas, in Nunley JA, Pfeffer GB, Sanders RW, Trepman E (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 481-484.
Amis JA, Siverhus SW, Liwnicz BH: An anatomic basis for recurrence after Morton’s neuroma excision. Foot Ankle 1992;13:153-156.

Question 78

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? Review Topic

Explanation

Spine MRI
Standing radiographs of the bilateral feet
Gastrocnemius stretching and nightime use of ankle foot orthosis
Gastrocnemius stretching and use of UCBL orthotic when ambulating
Gastrocnemius stretching
The patient is presenting with bilateral flexible pes planovalgus (or flexbile flatfoot). The most appropriate treatment in patients with a tight heel cord and no pain is gastrocnemius stretching
A flexible flatfoot in a child typically resolves spontaneously. Radiographs are typically indicated when there is pain to rule out other conditions. Treatment for patients without pain includes observation and gastrocnemius stretching. If there is pain, soft arch support or a more rigid UCBL can be used, but orthotics do not change the natural history. In patients with continued tightness in the heel cord despite aggressive stretching, gastrocnemius lengthening may be necessary.
Mosca reviews the management of flexible flatfeet in children and adolescents. He reports that there is no compelling evidence that an arch can be created with use of
orthotics. He proposes the following algorithm: patients with asymptomatic flatfeet are observed; symptomatic flatfeet with tight heel cords undergoing stretching until they become asymptomatic; symptomatic flatfeet with tight heel cords that do not respond to stretching (rare cases) are considered for surgery.
Figure A shows a young a patient with bilateral flatfeet when standing. Incorrect Answers:
abnormalities can seen in patients with cavovarus deformity Answer 2: Radiographs are indicated when there is pain to rule out other conditions. Answer 3: Ankle foot orthoses are not used for pes planovalgus Answer 4: UCBL would be indicated if the patient was having pain.
(SBQ13PE.42) Submuscular bridge plating is appropriate treatment for which of the following? Review Topic
A 2-month-old female with displaced, spiral, mid-diaphyseal femur fracture
A 26-month-old boy with a displaced spiral mid-diaphyseal femur fracture with
<2cm shortening
A 7-year old boy with a transverse, non-comminuted mid-diaphyseal femur fracture
A 7-year-old boy with a highly comminuted mid-diaphyseal femur fracture
A 15-year-old girl with a displaced butterfly fragmented mid-diaphyseal femur fracture
Submuscular bridge plating is appropriate for length-unstable femur fractures in skeletally immature patients ages 6 years and older.
Traditional plating of diaphyseal femur fractures in children has been abandoned due to the large incision and significant periosteal stripping involved. Submuscular plating with limited incisions and percutaneously applied fixation is a more biologically friendly way to achieve rigid internal fixation in length-unstable fracture patterns. External fixation is another acceptable option for these fractures. Locked plating, on the other hand, provides an 'internal external fixator,' avoids pin site issues and allows rapid mobilization while providing a biologically favorable environment for healing.
Kocher et al. provide the AAOS Clinical Practice Guideline for the treatment of pediatric diaphyseal femur fractures. They concluded that there was insufficient evidence regarding submuscular bridge plating to include it in the guideline.
Flynn et al. review the management of pediatric femoral shaft fractures. The note that
the narrow indications for plating of pediatric femoral fractures are open fractures, multiple trauma, head injury or compartment syndrome in patients less than 12 years old. Plating allows rigid fixation with readily available equipment and allows for rapid mobilization.
Hedequist et al. present a Technical Tricks paper in which they detail their surgical technique for submuscular bridge plating. They recommend this fixation strategy for patients between age 6 and skeletal maturity with comminuted diaphyseal femur fractures that are not easily treated by other methods.
Illustration A shows a preoperative and postoperative radiograph of a comminuted pediatric femur fracture treated with submuscular plating.
Incorrect answers:
(SBQ13PE.88) A 12-month-old boy attends a government regulated childcare center. His parents are called after a fall. Non-accidental trauma has been ruled out. On physical examination the right elbow is swollen and tender. He is unwilling to allow you to move the arm. Radiographs of the elbow are shown in Figure A. What is the orthopaedic management of this injury? Review Topic

Observation only
Elbow sling for 3 to 4 weeks
Rigid elbow immobilisation for 4 to 5 weeks
Admit for 24-48 hours for continuous intracompartmental pressure measurements
Operative fixation with percutaneous pinning PREFERRED RESPONSE 5
This patient presents with a distal humeral physeal separation. The most appropriate treatment would be closed reduction with internal fixation with percutaneous pins.
Displaced distal humerus physeal separation is typically seen in children under the age of 3 and has a high association with child abuse. The diagnosis can be a difficult as radiographs of a distal humeral physeal separation may be subtle. Often, radiographs show no obvious fracture, but can appear like an elbow dislocation since the secondary ossification centers have not yet developed. MRI or arthrogram can be used to aid in diagnosis.
Shrader et al. reviewed pediatric supracondylar fractures and pediatric physeal elbow fractures. They state the key to diagnosis of distal humerus physeal separation is the assessment is the radial head–capitellum relationship. These injuries should be fixed with closed reduction and smooth wire pinning. An elbow arthrogram may be considered intraoperatively for these patients because of the difficulty visualizing the distal humeral anatomy in children so young.
Skaggs et al. reviewed the diagnosis and management of pediatric elbow fractures. He states that child abuse should be suspected in all cases of elbow fracture when the child is less than 3 years of age and/or the injury pattern occur from a shearing mechanism. The displacement of physeal elbow fractures is almost always posteromedial.
Figure A shows AP and lateral radiographs with posteromedial displacement of the radial and ulnar shafts relative to the distal humerus. This is consistent with distal humeral physeal separation.
Incorrect Answers:

Question 79

A 25-year-old man has an isolated flexor digitorum profundus laceration just proximal to the distal interphalangeal (DIP) flexion crease of his ring finger. The tendon ends are trimmed, removing 10 mm from each end (secondary to fraying) and the tendon repaired. Four months later, he reports limited finger motion of the long, ring, and small fingers. He cannot fully extend his wrist and all joints of the 3 fingers simultaneously. He has full passive flexion but cannot actively completely close his fingers into a fist. What is the most likely cause?

Explanation

EXPLANATION:
If a single flexor digitorum profundus (FDP) tendon is debrided more than 1 cm prior to repair, the tendon is advanced too far distally, essentially shortening the musculotendon unit. The finger will likely develop a flexion posture. Because of the common muscle belly and interconnections of the profundi, the long and small fingers adjacent to the injured finger will be affected because of loss of some of their normal proximal excursion. The result is an inability of the adjacent fingers to completely flex. This condition, known as quadrigia, is named after the Roman chariot driver who held control of the reins of 4 horses, forcing them to move as 1. Quadrigia occurs when the FDP tendon is advanced too far distally, when a tendon graft is too short, or when the profundus is sutured over the end of an amputated digit. Intrinsic muscles of the hand flex the metacarpophalangeal (MP) joints and extend the PIP joint. Intrinsic tightness causes decreased PIP flexion when the MP joint is in extension. The lumbrical muscle modulates tension on the flexor profundus tendon. When a tendon graft to repair the profundus tendon is too long, a lumbrical plus deformity occurs. This is a paradoxical PIP extension as the finger is flexed. Disruption of the tendon
repair causes limited flexion of the injured finger.

Question 80

A 29-year-old patient sustains a closed, displaced joint depression intra-articular calcaneus fracture. In discussing potential complications of surgical intervention through an extensile lateral approach, which of the following is considered the most common complication following surgery?

Explanation

DISCUSSION: Delayed wound healing and wound dehiscence is the most common complication of surgical management of calcaneal fractures through an extensile lateral approach, occurring in up to 25% of patients. Most wounds ultimately heal with local treatment; the deep infection rate is approximately 1% to 4% in closed fractures. Posttraumatic arthritis may develop despite open reduction and internal fixation, but the percentages remain low. Peroneal tendinitis may occur from adhesions within the tendon sheath or from prominent hardware but is relatively uncommon. Nonunion of a calcaneal fracture is rare.
REFERENCES: Sanders RW, Clare MP: Fractures of the calcaneus, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 2, pp 2017-2073.
Sanders RW, Clare MP: Fractures of the calcaneus, in Bucholz RW, Heckman JD,

Court-Brown C (eds): Rockwood and Green’s Fractures in Adults, ed 6. Philadelphia, PA, Lippincott Williams & Wilkins, 2006, vol 2, pp 2293-2336.

Question 81

A patient undergoes a proximal tibial resection that is reconstructed with a fresh frozen osteoarticular allograft. Eleven months later, the graft is retrieved. Histologically, the articular cartilage and subchondral bone retrieved would be expected to show evidence of

Explanation

DISCUSSION: Osteoarticular allografts are devoid of host chondrocytes but do contain “mummified” cellular debris left over from donor processing. The cartilage architecture is preserved in the first 2 to 3 years after transplantation. The articular surface is covered with a pannus of fibrocartilage maintaining the joint space radiographically; this pannus later contains islands of fibrocartilage containing host mesenchymal stem cells. Degenerative changes to the joint surface occur earlier and are more severe in joints that are unstable. Only with degenerative changes at the surface is there histologic evidence of subchondral revascularization. Often degenerative changes involving the articular cartilage reach the tidemark, but the tidemark itself remains structurally intact.
REFERENCES: Enneking WF, Campanacci DA: Retrieved human allografts:

A clinicopathological study. J Bone Joint Surg Am 2001;83:971-986.
Enneking WF, Mindell ER: Observations on massive retrieved human allografts.

J Bone Joint Surg Am 1991;73:1123-1142.

Question 82

Deep posterior compartment

Explanation

DISCUSSION
The structures at risk are the anterior tibial artery and deep peroneal nerve in the anterior compartment, superficial peroneal nerve in the lateral compartment, sural nerve in the superficial posterior compartment, and posterior tibial nerve and posterior tibial and peroneal arteries and veins in the deep posterior compartment.

Question 83

Which of the following is considered a limitation of the Short Form 36 (SF-36) general health status instrument when applied to musculoskeletal conditions?

Explanation

Health outcome surveys are often either general or condition specific. The SF-36 (a general health-based survey) is the most widely applied general health status instrument. It measures three aspects of health: functional ability, well being, and overall health. Eight domains of quality of life are measured to quantify these aspects. It is designed to be self-administered by the patient. Because it is a patient-derived assessment, with patient-derived outcome measures, the patient's perspective is integrated and objectivity enhanced. The inherent bias of surgeon-driven formats is thus avoided. The SF-36 has been validated and normative population data obtained.
Multilingual validated translations have been produced in addition to international population data sets. The survey can be patient self-administered via office visit, mail, or telephone. A bias of lower over upper extremity function with regard to outcome measures employing the SF-36 has been demonstrated. Limits on the detection of certain changes in quality of life status may impose ceiling and floor effects on analysis and interpretation.

Question 84

A 3-year-old patient with L3 myelomeningocele has bilateral dislocated hips. Management should consist of

Explanation

DISCUSSION: In patients with myelomeningocele, the presence of bilateral hip dislocation does not affect ambulation, bracing requirements, sitting ability, degree of scoliosis, or level of comfort. There is little evidence to support active treatment of bilateral hip dislocations in patients with myelomeningocele proximal to L4.
REFERENCES: Fraser RK, Hoffman EB, Sparks LT, et al: The unstable hip and mid-lumbar myelomeningocele. J Bone Joint Surg Br 1992;74:143-146.
Richards BS (ed): Orthopaedic Knowledge Update: Pediatrics. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 65-76.

Question 85

A 26-year-old man has recurrent right knee pain. Figures 9a and 9b show consecutive sagittal T2-weighted MRI scans, and Figure 9c shows a coronal T1-weighted MRI scan. What is the most likely diagnosis?

Explanation

DISCUSSION: A discoid meniscus is a large disk-like meniscus. It is seen in the lateral meniscus in 3% of the population; a discoid medial meniscus is much less common. It can be identified on the coronal view by noting meniscal tissue extending into the tibial spine at the intercondylar notch.
The average width of a normal meniscus is less than 11 mm. A bow-tie appearance should not be seen on more than two consecutive sagittal images because the conventional thickness of the sagittal slices is 3 mm and the interval between two consecutive slices is 1.5 mm. Two sagittal slices will cover a 9-mm thickness. A discoid meniscus can be diagnosed on the sagittal views by noting a bow-tie appearance on more than two consecutive images.
REFERENCES: Helms CA: MR image of the knee, in Fundamentals of Skeletal Radiology, ed 2. Philadelphia, PA, WB Saunders, 1995, pp 172-191.
Mink JH, Deutsch AL: The knee, in MRI of the Musculoskeletal System, ed 1. New York, NY, Raven Press, 1990, pp 251-387.

Question 86

Which of the following nerves is most likely responsible for symptoms associated with plantar fasciitis?

Explanation

DISCUSSION: The first branch of the lateral calcaneal nerve innervates the abductor digiti minimi. It is reported to be trapped at the interval between the abductor hallucis and the quadratus plantae muscles.
REFERENCE: Baxter DE, Pfeffer GB, Thigpen M: Chronic heel pain: Treatment rationale. Orthop Clin North Am 1989;20:563-569.

Question 87

A 16-year-old girl who swims on her high school team reports pain in the shoulder after swimming. History reveals a glenohumeral dislocation at age 14 years while doing the backstroke. Examination shows a positive anterior apprehension sign. Treatment at this time should consist of

Explanation

p.579: “The Putti-Platt procedure is contraindicated in multidirectional instability (AMBRI); tightening the front of the shoulder will only increase the likelihood of posterior instability. In traumatic instability (TUBS) the data suggest that such a procedure, which limits external rotation is not necessary if the Bankart lesion is solidly repaired.”
p. 577: “A vigorous effort to stabilize the shoulder with exercises is particularly indicated in patients with multidirectional or posterior instability and in athletes requiring a completely normal or supranormal range of motion.”
p. 989: “If the [swimmer] has symptoms of subluxation, a conservative program that strengthens the external rotators is warranted. Surgery is seldom indicated.”

Question 88

A 66-year-old woman with known poorly controlled rheumatoid arthritis reports that for the past 4 weeks she has been unable to extend the metacarpophalangeal (MCP) joints of her right hand index, middle, ring and little fingers. She cannot hyperextend the thumb interphalangeal joint. Active wrist extension is possible, but shows radial deviation. Examination reveals mild synovitis at the wrist and MCP joints of the affected hand. There is no ulnar deviation at the MCP joints with normal alignment. When the MCP joints are passively extended, the patient is unable to maintain them in this position. There is no piano key sign at the distal ulna. Passive wrist motion shows a normal tenodesis effect. Which of the following would most likely confirm your diagnosis? Review Topic

Explanation

There are many causes of inability to extend the MCP joints in a patient with rheumatoid arthritis. The most common cause is rupture of the extensor tendons. An intact tenodesis test suggests that the extensor tendons are intact, thus surgical exploration is not indicated and would not confirm the diagnosis. The patient has normal alignment of the fingers without ulnar deviation, suggesting that there are no MCP dislocations to account for the inability to extend the MCP joints; therefore, radiographs would not confirm the diagnosis. The most likely cause of inability to extend the fingers in this patient is posterior interosseous nerve (PIN) palsy. Electrodiagnostic studies would confirm the presence of PIN palsy. An MRI of the elbow may show synovitis at the radiocapitellar joint, which can cause the PIN palsy. This finding however, is nonspecific and many patients without PIN palsy would also demonstrate synovitis at the radiocapitellar joint. Therefore, although an MRI would be helpful in localizing a potential cause of PIN compression, it would not in itself confirm the diagnosis.

Question 89

An osteoconductive bone graft material has which of the following properties?

Explanation

Osteoconductive bone graft material is described as the scaffold that allows new bone growth. This new bone is created via sprouting capillaries, perivascular tissue, and osteoprogenitor cells on the three-dimensional graft structure, permitting creeping
substitution, which allows for graft incorporation. An osteoinductive graft will stimulate the recruitment of progenitor cells that can differentiate into osteoblastic cells. Specific BMPs are osteoinductive. Osteogenic material contains viable cells with the ability to form bone. The ability to provide osteoprogenitor cells is only seen in fresh autograft. Other grafts rely on the recruitment of host progenitor cells to differentiate.

Question 90

A 21-year-old man has had posterior neck discomfort for the past 6 months. A whole-body bone scan and a cervical single-photon emission CT reveal increased activity at the C7 spinous process. MRI reveals multifocal involvement of the spinous process lamina and facet of C7. A CT-directed needle biopsy reveals osteoblastoma. What is the best course of action?

Explanation

DISCUSSION: En bloc excision is the recommended treatment of osteoblastoma. Treatment should consist of en bloc removal of the lamina, facet, and spinous process. Facet removal would necessitate fusion. Radiation therapy is not recommended. Intralesional curettage has a high rate of recurrence.
REFERENCES: Bridwell KH, Ogilvie JW: Primary tumors of the spine, in Bridwell KH, DeWald RL (eds): The Textbook of Spinal Surgery. Philadelphia, PA, JB Lippincott, 1991, vol 2, pp 1143-1174.
Ozaki T, Liljenquist U, Hillmann A, et al: Osteoid osteoma and osteoblastoma of the spine: Experience with 22 patients. Clin Orthop 2002;397:394-402.

Question 91

When counseling a patient with hypophosphatemic rickets, which of the following scenarios will always result in a child with the same disorder?

Explanation

DISCUSSION: Hypophosphatemic rickets is an inherited disorder that is transmitted by a unique sex-linked dominant gene. Therefore, if a male patient has a female offspring, his affected X chromosome will be transmitted and all of his female children will have hypophosphatemic rickets. All male offspring of a male patient will be unaffected. All offspring of a female patient have a 50% chance of having the disorder. Understanding the inheritance of hypophosphatemic rickets facilitates early diagnosis and early treatment. Medical treatment with phosphorus and some types of vitamin D (most authors recommend calcitriol) improves, but does not fully correct, the mineralization defect in hypophosphatemic rickets. However, if medical treatment is begun before the child begins walking, the growth plate is then adequately protected and a bowleg deformity will most likely be prevented.
REFERENCES: Evans GA, Arulanantham K, Gage JR: Primary hypophosphatemic rickets: Effect of oral phosphate and vitamin D on growth and surgical treatment. J Bone Joint Surg Am 1980;62:1130-1138.
Greene WB, Kahler SG: Hypophosphatemic rickets: Still misdiagnosed and inadequately treated. South Med J 1985;78:1179-1184.

Question 92

Figure 12 shows the radiograph of an 80-year-old woman who has had an 8-month history of back pain after a fall. What is the most likely diagnosis based on the radiographic findings at the fractured vertebrae?

Explanation

DISCUSSION: An intravertebral vacuum cleft suggests nonunion of the vertebral fracture with osteonecrosis and is not seen in routine healing fractures. MRI characteristically shows a high T2 signal in the cleft. The cleft is not indicative of an infectious or neoplastic lesion. A vacuum disk phenomenon is associated with end-stage degenerative disk disease, but those findings are not found in the vertebral body.
REFERENCES: Murakami H, Kawahara N, Gabata T, et al: Vertebral body osteonecrosis without vertebral collapse. Spine 2003;28:E323-E328.
Jang JS, Kim DY, Lee SH: Efficacy of percutaneous vertebroplasty in the treatment of intravertebral pseudarthrosis associated with noninfected avascular necrosis of the vertebral body. Spine 2003;28:1588-1592.

Question 93

Which of the following methods of meniscal repair has the highest load to failure strength?

Explanation

DISCUSSION: Numerous experimental studies have shown that vertical suture techniques are superior to all of the other noted methods. In fact, vertical sutures have been shown to be twice as strong as several of these techniques.
REFERENCES: DeHaven KE: Meniscus repair. Am J Sports Med 1999;27:242-250.
Dervin GF, Downing KJ, Keene GC, McBride DG: Failure strengths of suture versus biodegradable arrow for meniscal repair: An in vitro study. Arthroscopy 1997;13:296-300.
Barber FA: Endoscopic meniscal repair: The T-fix technique. Sports Med Arthroscopy Rev 1999;7:28-33.

Question 94

A 58-year-old man has had a 3-year history of recurrent ulcerations of the left ankle and instability despite multiple attempts at custom bracing, contact casting, and surgical debridement. He has an ankle-brachial index of 0.76. A clinical photograph and radiographs are shown in Figures 16a through 16c. Treatment should now consist of

Explanation

DISCUSSION: Nonsurgical management has failed to provide relief; therefore, the treatment of choice is arthrodesis with an intramedullary nail. Amputation may be indicated if the arthrodesis fails. The patient does have adequate circulation for an attempt at salvage. Total ankle arthroplasty is not indicated in a neuropathic patient.
REFERENCES: Pinzur MS, Kelikian A: Charcot ankle fusion with a retrograde locked intramedullary nail. Foot Ankle Int 1997;18:699-704.
Herbst SA: External fixation of Charcot arthropathy. Foot Ankle Clin 2004;9:595-609.

Question 95

What is the most likely complication after surgical treatment in this scenario?

Explanation

DISCUSSION
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, and 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 4 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 4 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 Brighton sign findings would be negative), a posterior capsular shift with rotator interval closure is indicated. If a patient has excessive glenoid retroversion, a posterior opening-wedge osteotomy is appropriate.
The most common complication seen after arthroscopic posterior labral repair is stiffness, followed by recurrent instability and degenerative joint disease.

Question 96

A high school athlete reports the sudden onset of low back pain while performing a dead lift. Examination reveals lumbar paraspinal spasm and a positive straight leg raising test. Deep tendon reflexes, motor strength, and sensation in the lower extremities are normal. Radiographic findings are normal. If symptoms persist for longer than a few weeks, what is the best course of action?

Explanation

DISCUSSION: In the adolescent population, a lumbar herniated disk is characterized by a paucity of clinical findings, with a positive straight leg raising test the only consistently positive finding. This may result in a prolonged period of nonsurgical management that fails to provide relief. Activities that place a significant shear load on the lumbar spine, such as the dead lift, are associated with an increased risk of central disk herniation. An adolescent who lifts weights and has a history of back pain that fails to respond to a short period of active rest should undergo MRI evaluation for the diagnosis of a lumber herniated disk.
REFERENCES: Epstein JA, Epstein NE, Marc J, et al: Lumbar intervertebral disk herniation in teenage children: Recognition and management of associated anomalies. Spine 1984;9:427-432.
Hashimoto K, Fujita K, et al: Lumbar disc herniation in children. J Pediatr Orthop

1990;10:394-396.

Question 97

Which of the following factors is most commonly associated with mechanical failure of a cemented total hip arthroplasty?

Explanation

DISCUSSION: Varus position of the stem is most commonly associated with failure of the cemented femoral component because of association with an inadequate cement mantle in the proximal medial and distal lateral zones. An inadequate cement mantle and obesity have been associated with increased loosening but not as frequently as a varus deformity. The influences of gender and osteoporotic bone on the outcome of cemented femoral components have not been established.
REFERENCES: Maloney WJ III: Primary cemented total hip arthroplasty, in Callaghan JJ, Dennis DA, Paprosky WG, Rosenberg AG (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1995, pp 179-189.
Callaghan JJ, Salvati EA, Pellicci PM, Wilson PD Jr, Ranawat CS: Results of revision for mechanical failure after cemented total hip replacement, 1979 to 1982: A two- to five-year follow-up. J Bone Joint Surg Am 1985;67:1074-1085.

Question 98

Oxidation of polyethylene after sterilization occurs most rapidly when the implant undergoes

Explanation

DISCUSSION: The use of gamma radiation to sterilize polyethylene will result in the formation of free radicals in the material that increase the susceptibility of the material to oxidation and wear. The packaging can also have an impact. If the polyethylene is packaged in air, the oxygen in the packaging can significantly oxidize the material on the shelf prior to clinical use. Gas plasma and ethylene oxide sterilization do not appear to increase oxidation of polyethylene.
REFERENCES: Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 449-486.
Wright TM: Ultra-high molecular weight polyethylene, in Morrey BF (ed): Joint Replacement Arthroplasty. New York, NY, Churchill Livingstone, 1991, pp 37-46.
Collier JP, Sutula LC, Currier BH, et al: Overview of polyethylene as a bearing material: Comparison of sterilization methods. Clin Orthop 1996;333:76-86.
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Question 99

..Figures 112a and 112b are the anteroposterior and lateral radiographs of a 65-year-old man who has a significant history of tobacco abuse and a 6-week history of right thigh pain. Axial and sagittal MRI scans are seen in Figures 112c and 112d. His MR angiogram is shown in Figure 112e. A biopsy of a lesion is shown in Figure 112f. What is the most likely diagnosis?

Explanation

CLINICAL SITUATION FOR QUESTIONS 113 THROUGH 116
Figures 113a and 113b are the radiographs of a 68-year-old-man who has increasing pain in his left groin with weight-bearing activities and a Trendelenburg gait. Radiographs reveal a lytic lesion of the greater trochanter. An initial diagnosis of adenocarcinoma of the lung was made 1 year before this presentation. His lung cancer treatment consisted of partial lobectomy and postsurgical radiation therapy.

Question 100

A 21-year-old man who was injured in a snowboarding accident 18 months ago now reports wrist pain. An MRI scan is shown in Figure 37. Based on the image findings, what is the most likely diagnosis?

Explanation

DISCUSSION: The coronal MRI scan of the wrist shows the scaphoid. There is a subtle fracture line with a step-off at the radial surface consistent with a nonunion. The signal intensity is markedly different between the two fragments of the scaphoid. This strongly suggests osteonecrosis. Preiser’s disease is osteonecrosis typically involving most or all of the scaphoid. Kienbock’s disease involves the lunate. Intraosseous ganglia are easily diagnosed on MRI but typically have a fluid-filled area surrounded by denser bone in the periphery. Scapholunate dissociation can be seen on MRI as an injury to the scapholunate ligament and widening of the scapholunate interval, neither of which is seen on this image.
REFERENCE: Perlik PC, Guilford WB: Magnetic resonance imaging to assess vascularity of scaphoid nonunions. J Hand Surg Am 1991;16:479-484.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

posterior spinal fusion with instrumentation.
a thoracolumbosacral orthosis (TLSO) extension brace and early mobilization.
bed rest for 6 weeks followed by mobilization in a cast.
anterior L1 corpectomy and fusion with instrumentation.
anterior corpectomy followed by posterior fusion with instrumentation.

Correct Answer: a thoracolumbosacral orthosis (TLSO) extension brace and early mobilization.

Explanation:

Question 2:

Options:

Limit flexion to 90 degrees with nonweight-bearing activity with crutches for the first 6 weeks
Limit flexion to 30 degrees for the first week, progress 10 degrees per week, and allow partial weight-bearing activity with crutches
The knee should be immobilized in extension; partial weight-bearing activity with crutches may be allowed for the first 6 weeks
An initial range-of-motion restriction to 90 degrees or weight-bearing restriction is not needed

Correct Answer: An initial range-of-motion restriction to 90 degrees or weight-bearing restriction is not needed

Explanation:

Question 3:

- Work-related injuries to the lower back are most often related to which of the following risk factors?

Options:

Female gender
History of cigarette smoking
L5-S1 spondylolisthesis on pre-employment radiography
Decreased strength of the lower extremities on pre-employment testing
Decreased flexibility of the lumbar spine on pre-employment testing

Correct Answer: History of cigarette smoking

Explanation:

Question 4:

Options:

MRI
Bone Scan
CT scan
Diagnostic injection
Repeat radiographs

Correct Answer: MRI

Explanation:

Question 5:

Following an episode of transient quadriplegia in contact sports, an athlete’s return to play is absolutely contraindicated when

Options:

the spinal canal to vertebral body ratio (Torg ratio) is less than or equal to 0.8.
electromyelographic studies are abnormal.
MRI scans or contrast-enhanced CT scans show severe spinal stenosis.
unilateral burning pain persists.
the episode of quadriplegia lasts 5 minutes.

Correct Answer: MRI scans or contrast-enhanced CT scans show severe spinal stenosis.

Explanation:

Question 6:

Options:

Flexor hallucis longus transfer to the Achilles tendon
Peripheral vascular bypass
Jones procedure (extensor hallucis longus transfer to the first metatarsal with interphalangeal joint fusion)
Posterior tibial tendon transfer to the anterior tibialis tendon
Achilles tendon lengthening

Correct Answer: Achilles tendon lengthening

Explanation:

Question 7:

Based on the injury shown on the axial MRI scan of the shoulder in Figure 1, what other pathology should be closely examined for during surgery?

Options:

Subscapularis tear
Supraspinatus tear
Superior labral anterior-posterior (SLAP) tear
Bankart tear

Correct Answer: Subscapularis tear

Explanation:

Question 8:

What is the most important factor regarding the risk of recurrent instability in a patient with an acute anterior dislocation of the shoulder?

Options:

Age of the patient
Time from injury to reduction
Completion of 3 weeks of immobilization
The degree of athletic participation
Bilateral instability

Correct Answer: Age of the patient

Explanation:

Question 9:

Options:

chemotherapy, wide resection, and endoprosthetic reconstruction.
radiation therapy only.
chemotherapy only.
prophylactic internal fixation with a locked intramedullary rod.
open curettage, bone grafting, dynamic hip screw fixation, and radiation therapy.

Correct Answer: prophylactic internal fixation with a locked intramedullary rod.

Explanation:

Question 10:

Options:

Inadequate restoration of the joint line
Patellar tendon rupture
Excessive internal rotation of the tibial component
Flexion gap instability
Hyperextension of the femoral component

Correct Answer: Flexion gap instability

Explanation:

DISCUSSION: Instability is a leading cause of failure following total knee arthroplasty. Instability can present as global instability, extension gap (varus/valgus) instability, or flexion gap (anterior/posterior) instability. Treatment options are numerous based on the exact pathology. The radiograph reveals anterior/posterior instability with dislocation consistent with flexion gap instability. A loose flexion gap can allow the femoral component to ride above the tibial cam post mechanism, resulting in dislocation. Distal femoral augments treat extension gap instability, whereas tibial augments can treat both flexion and extension gap instability. Posterior condyle augments at the distal femur can also be used to treat flexion gap instability. Flexion gap instability is further aggravated by extension mechanism incompetence. Note the excessively thin patella on the lateral radiograph.
REFERENCES: Pagnano MW, Hanssen AD, Lewallen DG, et al: Flexion instability after primary cruciate retaining total knee arthroplasty. Clin Orthop 1998;356:39-46.
McAuley J, Engh GA, Ammeen DJ: Treatment of the unstable total knee arthroplasty. Inst Course Lect 2004;53:237-241.
Naudie DD, Rorabeck CH: Managing instability in total knee arthroplasty with constrained and linked implants. Instr Course Lect 2004;53:207-215.

Question 11:

-If a physician elects to shorten a femur by 4 cm for traumatic bone loss treatment and places an intramedullary nail for fixation, which deformity will be created in the lower extremity?

Options:

Patella alta
Medial mechanical axis deviation
Lateral mechanical axis deviation
Increased anatomic tibiofemoral angle
Translation of the anatomical axis of the femur

Correct Answer: Medial mechanical axis deviation

Question 12:

Options:

Iliotibial band bursectomy
Z-lengthening of the iliotibial band
Partial excision of the iliotibial band
Home stretching program and cross training

Correct Answer: Home stretching program and cross training

Explanation:

Question 13:

Options:

Obtain a CT scan to assess the injury.
Obtain an MRI scan to assess for osteonecrosis.
Reduce the hip and evaluate hip stability.
Perform open reduction of the hip in the operating room.
Ask the emergency room physician to transfer the patient to a higher level trauma center.

Correct Answer: Reduce the hip and evaluate hip stability.

Explanation:

Question 14:

What is the main biologic effect of aggrecan in cartilage? Review Topic

Options:

Extracellular matrix protein involved in the organization of collagen
Proteoglycan involved in the hydrophilic behaviour of cartilage
Cartilage matrix protein that plays a role in cartilage tissue organization
Collagen component responsible for stability
Non-collagenous extracellular matrix protein that regulates chondrocyte proliferation

Correct Answer: Extracellular matrix protein involved in the organization of collagen

Explanation:

Question 15:

The orthosis shown in Figure 47 is commonly used for

Options:

hallux rigidus.
midfoot arthritis.
second metatarsal stress fracture.
bunionette deformity.
heel pain.

Correct Answer: hallux rigidus.

Explanation:

Question 16:

Which of the following changes occur in articular cartilage with age?

Options:

Cell numbers increase with fairly uniform distribution.
Chondroitin sulfate concentration increases.
Keratin sulfate concentration decreases.
Proteoglycan synthesis decreases.
Water content increases.

Correct Answer: Proteoglycan synthesis decreases.

Explanation:

Question 17:

Options:

a program of shoulder strengthening exercises.
decompression of the nerve at the spinoglenoid notch.
decompression of the nerve at the transverse suprascapular ligament.
release of the fascial elements of the muscle tethering the nerve.
arthroscopy, repair of the posterior labrum lesion, and an anterior capsular shift.

Correct Answer: a program of shoulder strengthening exercises.

Explanation:

Question 18:

What percent of patients initially diagnosed with classic, high-grade osteosarcoma of the extremity have visible evidence of pulmonary metastasis on CT of the chest?

Options:

5% to 10%
10% to 20%
40% to 50%
60% to 80%
80% to 90%

Correct Answer: 10% to 20%

Explanation:

Question 19:

Ulnohumeral distraction interposition arthroplasty is considered the most appropriate treatment for which of the following patients?

Options:

A 41-year-old man with painful posttraumatic arthritis of the elbow
A 45-year-old laborer with painful primary osteoarthritis
A 51-year-old patient with polyarticular rheumatoid arthritis and multiple joint involvement
A 71-year-old woman with stage IV rheumatoid arthritis of the elbow
A 71-year-old patient with painful radiocapitellar arthritis from rheumatoid arthritis

Correct Answer: A 41-year-old man with painful posttraumatic arthritis of the elbow

Explanation:

Question 20:

Which of the following aids in correction of patellar tracking after total knee arthroplasty (TKA)?

Options:

Internal rotation of the femoral component
Internal rotation of the tibial component
Increasing size of the tibial component
Medialization of the patellar component
Joint line elevation

Correct Answer: Medialization of the patellar component

Explanation:

DISCUSSION: Correct patellofemoral tracking has proven to be a crucial aspect in TKA because a large percent of problems after TKA are related to the patellofemoral articulation. External rotation of the femoral and tibial components has been shown to aid in tracking. Likewise, medialization of the patellar button aids in patellar tracking and prevention of lateral subluxations and dislocations. Attention to the distal femoral cut is critical in maintaining the joint line and preventing patella baja or alta. Tibial sizing, however, is not directly related to patellar tracking after TKA.
REFERENCES: Callaghan JJ, Rosenberg AG, Rubash HE, et al (eds): The Adult Knee. Philadelphia, PA, Lippincott Williams & Wilkins, 2003, pp 1245-1258.
Merkow RL, Soudry M, Insall JN: Patellar dislocation following total knee replacement. J Bone Joint Surg Am 1985;67:1321-1327.

Question 21:

Options:

aspiration and steroid injection.
rest.
acromioplasty.
arthroscopic repair and decompression.
rehabilitation.

Correct Answer: arthroscopic repair and decompression.

Explanation:

Question 22:

In patients without spondylolisthesis or scoliosis undergoing laminectomy for lumbar spinal stenosis, spinal fusion is generally recommended if Review Topic

Options:

a dural tear is repaired.
more than one level requires decompression.
less than one half of each facet is removed bilaterally.
the pars interarticularis is fractured.
the patient is a smoker.

Correct Answer: the pars interarticularis is fractured.

Explanation:

Question 23:

Options:

Remove the total ankle and place an antibiotic spacer
Debride and exchange polyethylene
Perform a below-the-knee amputation
Convert to a fusion with an intercalary allograft

Correct Answer: Debride and exchange polyethylene

Explanation:

Question 24:

What radiographic view will best reveal degeneration of the pisotriquetral joint in a patient who is being evaluated for pisotriquetral arthrosis?

Options:

True lateral
Lateral in 30 degrees of pronation
Lateral in 30 degrees of supination
Posteroanterior in 30 degrees of pronation
Carpal tunnel

Correct Answer: Lateral in 30 degrees of supination

Explanation:

Question 25:

Which of the following is considered the lowest level that a standard thoracolumbosacral orthosis (TLSO) can immobilize?

Options:

L1-2
L3-4
L5-S1
T9-10
T11-12

Correct Answer: L3-4

Explanation:

DISCUSSION: Without more distal immobilization such as a thigh extension, the lower two lumbar segments generally show the same or even increased mobility with a TLSO.
REFERENCES: White AA, Panjabi MM: Clinical Biomechanics of the Spine, ed 2. Philadelphia, PA, JB Lippincott, 1990, pp 475-509.
Norton PL
, Brown T: The immobilizing efficiency of back braces. J Bone Joint Surg Am 1957;39:111-139.

Question 26:

Options:

Complex regional pain syndrome
Osteoarthritis
Osteosarcoma
Osteonecrosis
Inflammatory arthritis

Correct Answer: Osteonecrosis

Explanation:

DISCUSSION: Osteonecrosis of the tibial plateau occurs infrequently. The symptoms are similar to those of idiopathic osteonecrosis of the medial femoral condyle and include pain and tenderness of the medial aspect of the knee and a slight synovitis. The range of motion of the knee remains within normal limits, and no gross deformity is present. Osteonecrosis of the tibial plateau is easily misdiagnosed as degenerative meniscus or osteoarthritis of the compartment of the knee. Review of lateral radiographs may reveal an osteopenic area in the subchondral bone of the medial tibial plateau. The diagnosis is more easily established with a bone scan where increased uptake of radionucleides is shown over the medial tibial plateau. In osteoarthritic involvement of the medial compartment, uptake is over both the medial femoral condyle and the medial tibial plateau, whereas if osteoarthritis involves the entire knee, uptake is diffuse over the entire joint. Radiographic findings in complex regional pain syndrome are normal as opposed to the findings for osteonecrosis or osteoarthritis. Osteosarcoma has a characteristic radiographic appearance of a bone-forming tumor. Loose bodies can derive from osteochondral fractures; a history of trauma is usually elicited. Osteoarthritis usually presents with joint space narrowing accompanying the weight-bearing pain.
REFERENCES: Soucacos PN, Berris AE, Xenakis TH, et al: Knee osteonecrosis: Distinguishing features in differential diagnosis, in Urbanik JR, Jones JD (eds): Osteonecrosis. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 413-424.
Ecker ML, Lotke PA: Osteonecrosis of the medial part of the tibial plateau. J Bone Joint Surg Am 1995;77:596-601.

Question 27:

Figure 62a and Figure 62b

Options:

Nerve palsy
Skin necrosis
Flexion instability
Patellar instability
Anterior knee pain
Malalignment

Correct Answer: Nerve palsy

Explanation:

Question 28:

Options:

High hip center
Anatomic hip center with trochanteric osteotomy and progressive femoral shortening
Anatomic hip center with subtrochanteric shortening osteotomy
Iliofemoral lengthening followed by an anatomic hip center

Correct Answer: Anatomic hip center with subtrochanteric shortening osteotomy

Explanation:

Question 29:

Options:

Per-protocol
Crossover analysis
Intent-to-treat
Bayesian analysis
Effect size

Correct Answer: Bayesian analysis

Explanation:

Question 30:

Options:

casting with an external bone stimulator.
ankle arthrodesis.
revision subtalar arthrodesis.
conversion to triple arthrodesis without revision of the subtalar arthrodesis.
conversion to triple arthrodesis with revision of the subtalar arthrodesis.

Correct Answer: conversion to triple arthrodesis with revision of the subtalar arthrodesis.

Explanation:

Question 31:

A 36-year-old nurse has had redness, pain, and small vesicles on the pulp of her middle finger for the past 3 days. Management should consist of

Options:

observation.
marsupialization of the nail fold.
application of copper sulfate.
application of calcium gluconate.
incision and drainage of the pulp.

Correct Answer: observation.

Explanation:

Question 32:

Options:

Continued dressing changes
Split-thickness skin graft
Full-thickness skin graft
Local rotational flap

Correct Answer: Local rotational flap

Explanation:

Question 33:

What gene is expressed the earliest during the differentiation of a chondrocyte during endochondral ossification?

Options:

Aggrecan
Sox-9
Collagen type II
Collagen type IV
Collagen type XI

Correct Answer: Sox-9

Explanation:

Question 34:

Options:

Proximal tibial varus osteotomy
Lateral unicompartmental arthroplasty
Distal femoral varus osteotomy
Total knee arthroplasty

Correct Answer: Distal femoral varus osteotomy

Explanation:

Question 35:

A 27-year-old man has neck pain after being involved in a motor vehicle accident. A lateral cervical radiograph is shown in Figure 21. What would be the most common neurologic finding?

Options:

Cruciate paralysis
Quadraplegia
Normal function
Absent bulbocavernosus reflex
Greater occipital nerve dysesthesia

Correct Answer: Normal function

Explanation:

Question 36:

Options:

0% if bracing is used
25%
50%
75%
90% or greater

Correct Answer: 90% or greater

Explanation:

Question 37:

-Four months after injury, the tibia is showing evidence of slow healing on radiographs. What is the optimal treatment for this potential nonunion?

Options:

Convert to circular external fixation
Exchange nailing and autograft
Exchange nailing and bone morphogenetic protein
Tibial plate
Observation until 6 months after injury

Correct Answer: Observation until 6 months after injury

Explanation:

DISCUSSION FOR QUESTIONS 108 THROUGH 110:
This patient is unstable and is not a good candidate for Early Total Care (ETC) and therefore should be managed by the tenets of Damage Control Orthopaedics (DCO). Débridement and external fixation is preferable for this patient. Intramedullary nails would be a component of ETC. Calcaneal traction is not considered ideal because it does not allow the patient to travel as easily. The S.P.R.I.N.T. study concluded that while reamed nails may offer benefit in closed fractures, there was no difference between reamed or unreamed nails in the treatment of open fractures of the tibia. Uniplanar external fixation and tibial plating are not considered the best options for open tibia fractures. Additional findings of the S.P.R.I.N.T. study conclude that delaying surgical intervention for at least 6 months after injury may reduce the need for reoperation.

Question 38:

Accurate evaluation of the upper portion of the subscapularis muscle is best accomplished with active internal rotation

Options:

in adduction and the arm in external rotation.
in adduction and the arm in neutral rotation.
with the dorsum of the hand on the buttocks.
with the dorsum of the hand on the midlumbar level.
with the palm of the hand pressing against the belly.

Correct Answer: with the palm of the hand pressing against the belly.

Explanation:

Question 39:

Options:

a non-weight-bearing short leg cast.
open reduction and internal fixation.
no weight bearing with motor exercises for 8 weeks.
debridement, curettage, and drilling.
an ankle brace or taping when participating in athletic activity.

Correct Answer: debridement, curettage, and drilling.

Explanation:

Question 40:

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 41:

What factor is associated with the highest risk for in-hospital complications for patients undergoing a lumbar fusion for degenerative spondylolisthesis? Review Topic

Options:

Hospital size
Gender
Race
Age
One comorbidity

Correct Answer: Age

Explanation:

Question 42:

Treatment of a cruciate-retaining total knee that is unstable in flexion is best accomplished by

Options:

revising the implant to a posterior stabilized device.
revising the implant with a thinner polyethylene insert.
revising the implant with a larger femoral component.
limiting flexion to only 90°.
using quadriceps conditioning exercises and a derotation brace.

Correct Answer: revising the implant to a posterior stabilized device.

Explanation:

Question 43:

Options:

Midsubstance tear of the lateral ulnar collateral ligament
Proximal avulsion of the ulnar collateral ligament
Proximal avulsion of the lateral ulnar collateral ligament
Distal bony avulsion of the ulnar collateral ligament from the sublime tubercle

Correct Answer: Proximal avulsion of the lateral ulnar collateral ligament

Explanation:

Question 44:

Pain associated with a proximal medial tibial osteochondroma in a 10-year-old patient is most commonly the result of

Options:

degeneration into a chondrosarcoma.
bursitis.
infection.
fracture through the base.
associated spinal stenosis.

Correct Answer: bursitis.

Explanation:

Question 45:

Options:

Continued activity restrictions for 6 more months or until asymptomatic
An aggressive physical therapy program that includes closed chain quadriceps strengthening
Arthroscopic drilling of the subchondral bone
Open debridement and screw fixation
Osteochondral autograft transplant procedure

Correct Answer: Arthroscopic drilling of the subchondral bone

Explanation:

Question 46:

Options:

Electrode placement
Stimulation failure
Anesthetic effect
Cord ischemia from retraction
Cerebral ischemia from retraction

Correct Answer: Cerebral ischemia from retraction

Explanation:

DISCUSSION: The change noted is focal and confined to the cortex, sparing the opposite side, both lower extremities, and the subcortical waveforms, making all the choices unlikely with the exception of carotid compression with focal cortical ischemia. This may be associated with poor collateral flow from the opposite hemisphere due to an incomplete circle of Willis.
REFERENCES: Drummond JC, Englander RN, Gallo CJ: Cerebral ischemia as an apparent complication of anterior cervical discectomy in a patient with an incomplete circle of Willis. Anesth Analg 2006;102:896-899.
Yeh YC, Sun WZ, Lin CP, et al: Prolonged retraction on the normal common carotid artery induced lethal stroke after cervical spine surgery. Spine 2004;29:E431-E434.

Question 47:

Options:

Lateral (fibular) condyle of the second metatarsal head
Second metatarsophalangeal sesamoid
Plantar condyle of the base of the proximal phalanx
Exostosis of the plantar second metatarsal head
Osteochondroma of the second metatarsal distal metaphysis

Correct Answer: Lateral (fibular) condyle of the second metatarsal head

Explanation:

Question 48:

Options:

Resurfacing hemiarthroplasty
Resurfacing hemiarthroplasty with fascial glenoid resurfacing
Resurfacing hemiarthroplasty with cemented glenoid component
Stemmed hemiarthroplasty
Stemmed total shoulder arthroplasty

Correct Answer: Stemmed hemiarthroplasty

Explanation:

Question 49:

Options:

Referral to a pain clinic for epidural injections
Activity modification and anti-inflammatory medications
Urgent hospital admission followed by hemilaminotomy and diskectomy
Hemilaminotomy and diskectomy scheduled as an elective procedure
Posterior laminectomy and fusion

Correct Answer: Referral to a pain clinic for epidural injections

Explanation:

The patient has an L5-S1 disk herniation, which has a favorable prognosis without surgical intervention. Most acute lumbar disk herniations resolve with nonsurgical management. The most appropriate course of initial treatment should be analgesics and activity modification, followed by rehabilitation as the symptoms allow. Although the MRI scan indicates a large disk herniation, he has no symptoms or signs that would warrant urgent surgical decompression. Planned elective diskectomy should be considered only if nonsurgical management fails to provide relief. Epidural injections could be considered if the initial course of treatment fails to give the patient significant relief. Posterior laminectomy and fusion is not indicated without the presence of instability.
(SBQ12SP.9) A 62-year-old male underwent posterior spinal instrumented fusion for degenerative lumbar spondylolithesis one year ago. He presents to office complaining of persistent lower back pain. The pain initially improved but over the last 6 months he has had recurring pain at the site of the surgery primarily with activity. He denies back pain at rest or night pain. Physical examination reveals a well healed wound and no physical abnormalities. He has no tenderness to palpation to the thoracic or lumbar spine. He has no neurological deficits. His laboratory results show an erythrocyte sedimentation rate (ESR) = 8 mm/h and C-reactive protein (CRP) = 3 mg/L at the last visit which are both within normal limits. Figure A shows a series of radiographs from his pre-operative, 3 month post-operative and 1 year post-operative clinic visits, respectively. Which of the following investigations would best confirm the suspected underlying diagnosis?
Review
Topic
MRI of lumbar spine
Repeat ESR/CRP and whole body bone scan
CT of lumbar spine
Dynamic flexion/extension plain film radiographs
Dynamic lateral bending plain film radiographs
This patient has clinical and radiographic features of failed spinal arthrodesis. CT scan have been shown to be the most relable method for assessing spinal fusion postoperatively.
Reported rates of nonunion following posterior spinal fusion range from 0-70%. Rates are variable due to the various operative techniques, underlying diagnoses as well as asymptomatic patients. Non-union may lead to changes in alignment, spinal instability and potential neurological injury. Static radiographs have long been used as a practical method of fusion assessment, but these tend to significantly overestimate the presence of a solid fusion. Lack of movement at a fused segment, on dynamic views, does not confirm fusion. CT offers excellent bony resolution and are less affected by metal artifact compared to MRI.
Patel et al. showed that tobacco use, malnutrition, oral anti-inflammatory use, multilevel fusion, prior spine surgery, and sagittal imbalance are all risk factors for spinal nonunion.
Mok et al. looked at erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels after spinal surgery and compared their usefulness as predictors of infectious complications in the early postoperative period. They found that CRP is more applicable, predictable, and responsive in the early postoperative period compared with ESR. Using a second rise or failure to decrease as expected for CRP is sensitive for infection.
Shelby et al. reviewed the radiological assessment of spinal fusion. They comment that fine-cut imaging, multiplanar reconstruction, and metal artifact reduction have increased the ability to assess fusion on CT.
Figure A shows a series of lateral radiographs of the lumbar spine with posterior spinal instrumentation. Illustration A shows a lateral CT scan image of multi-level pseudoarthrosis after posterior spinal instrumented fusion. Illustration B shows an
intra-operative
view
of
spinal
pseudoarthrosis
(white
arrow).
Incorrect
(SBQ12SP.19) A 41-year-old male presents with acute onset of low back pain that started when he was trying to lift a heavy box while helping his brother move apartments two days ago. The pain has been severe enough to cause him to miss work yesterday. He has no neurologic deficits. What are the chances he will return to work within 6 weeks?
Review Topic
1 80 to 90%
2 70 to 80%
3 60 to 70%
4 50 to 60%
5 40 to 50%
Most adults (up to 80%) will experience an episode of low back pain in their lifetime. In those whose pain is severe enough to cause them to miss work, 60 to 70% will return by 6 weeks, and 80 to 90% will return by 12 weeks.
Low back pain is common in adults. Most patients experience resolution of symptoms quickly and have no lasting loss of function. However, 5 to 10% develop chronic pain. Recurrence of pain is common, and is part of the natural history, occurring in 20 to 72% of patients. After 12 weeks, return to work rates are slow.
Shen et al. review the nonoperative management of acute and chronic low back pain. The authors note that none of the available interventions has been proven by high quality large randomized controlled trials. The authors believe that low dose oral
steroids are safe in the short term and that injection therapy should not be used without a reasonable presumptive diagnosis.
Madigan et al. review the management of lumbar degenerative disease. The authors emphasize that the majority of patients improve within 6 weeks with or without treatment. For patients that do not, the authors do not recommend epidural injection, as there are no good studies to support their use in the treatment of discogenic back pain. When surgical treatment is indicated they state that arthrodesis is the gold standard, although the long term results of total disk arthroplasty are being elucidated.
Illustration A shows a table of available non-operative treatment modalities for back pain. Illustration B shows a list of possible diagnoses associated with acute low back pain, with those associated with neurogenic pain italicized. Illustration C shows a list of 'red flag' symptoms indicating serious/emergent causes of low back pain.
Incorrect
2:
Longer
to than
90%

Question 50:

Which of the following tumors have characteristic chromosomal translocations?

Options:

Ewing’s sarcoma and osteosarcoma
Ewing’s sarcoma and conventional chondrosarcoma
Ewing’s sarcoma and synovial sarcoma
Osteosarcoma and conventional chondrosarcoma
Myeloma and malignant fibrous histiocytoma

Correct Answer: Ewing’s sarcoma and synovial sarcoma

Explanation:

Question 51:

Options:

The number of months he plays per year
The number of pitches he throws per game
The number of games he plays per week
His fastball speed
Playing in another position once being relieved of pitching

Correct Answer: Playing in another position once being relieved of pitching

Explanation:

Question 52:

A corset-type brace may help reduce symptoms during an episode of acute low back pain as the result of

Options:

decreased intervertebral motion in the sagittal plane.
decreased intervertebral motion in the coronal plane.
decreased intervertebral motion in the axial plane.
decreased intradiskal pressure.
increased intradiskal temperature.

Correct Answer: decreased intradiskal pressure.

Explanation:

Question 53:

Options:

Injury to the lumbar sympathetic chain
Injury to the parasympathetic nerve
Immune response to the allograft bone
Occlusion of the left iliac vein
Prolonged retraction of the left iliac artery

Correct Answer: Injury to the lumbar sympathetic chain

Explanation:

Question 54:

Options:

Transfer lesion to the fourth metatarsal head
Fifth toe fixed claw toe deformity
Ulceration at the level of the resected head
Peroneal atrophy
Charcot arthropathy with midfoot collapse and forefoot abduction

Correct Answer: Transfer lesion to the fourth metatarsal head

Explanation:

DISCUSSION: CMT is characterized by a cavovarus foot position that increases weight-bearing stresses along the lateral border. Removal of the fifth metatarsal head carries the risk of creating a transfer lesion at the fourth metatarsal head, particularly with a cavovarus foot. Claw toes are common in CMT, but the fifth toe would be flail in this situation. Ulceration is unlikely given the lack of underlying bone. Peroneal atrophy is associated with CMT but would not be a complication of this procedure. Charcot arthropathy is a neuropathic process frequently seen in individuals with diabetes mellitus.
REFERENCES: Kitaoka HB, Holiday AD Jr: Metatarsal head resection for bunionette: Long-term followup. Foot Ankle 1991;11:345-349.
Coughlin MJ, Mann RA, Saltzman CL: Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby, 2007, pp 1312-1315.

Question 55:

What significant structure is most at risk during a posterior approach of the Achilles tendon near its musculotendinous junction?

Options:

Saphenous vein
Saphenous nerve
Posterior tibial nerve
Sural nerve
Plantaris muscle

Correct Answer: Sural nerve

Explanation:

Question 56:

The main advantage of surgical repair of an acute Achilles tendon rupture, when compared with nonsurgical management, is reduced

Options:

stiffness of the ankle joint.
risk of deep venous thrombosis.
risk of rerupture.
cost of care.
tendon healing time.

Correct Answer: risk of rerupture.

Explanation:

Question 57:

The most appropriate next surgical procedure is

Options:

synovectomy.
debridement, synovectomy, and placement of a thicker polyethylene liner.
resection arthroplasty and placement of a cement antibiotic spacer.
conversion to total knee arthroplasty (TKA).

Correct Answer: conversion to total knee arthroplasty (TKA).

Explanation:

Question 58:

Options:

Anterior glenoid rim fracture tear
Anterior inferior labral tear
Posterior labral tear
Total capsular laxity
Osteochondral defect of the humeral head

Correct Answer: Posterior labral tear

Explanation:

DISCUSSION: Traumatic posterior instability is a common finding in football players, especially in the blocking positions as well as in the defensive linemen and linebackers.
A traumatic blow to the outstretched arm results in posterior glenohumeral forces. Labral detachment at the glenoid rim is common. Patients report slipping or pain with posteriorly directed pressure. Rarely do these patients have true dislocations that require reduction; however, recurrent episodes of subluxation or pain are not uncommon. Posterior repair has
been shown to be successful in the treatment of traumatic instability.
REFERENCES: Bottoni CR, Franks BR, Moore JH, et al: Operative stabilization of posterior shoulder instability. Am J Sports Med 2005;33:996-1002.
Williams RJ III, Strickland S, Cohen M, et al: Arthroscopic repair for traumatic posterior shoulder instability. Am J Sports Med 2003;31:203-209.
Kim SH, Ha KI, Park JH, et al: Arthroscopic posterior labral repair and capsular shift for traumatic unidirectional recurrent posterior subluxation of the shoulder. J Bone Joint Surg Am 2003;85:1479-1487.

Question 59:

In what decade does the peak incidence of conventional osteosarcoma occur?

Options:

First
Second
Fourth
Fifth
Sixth

Correct Answer: Second

Explanation:

Question 60:

Options:

closed reduction and application of a long leg cast.
open reduction and internal fixation with plate and screw fixation.
percutaneous plate fixation.
spanning external fixation with delayed limited open reduction and internal fixation.
primary ankle arthrodesis.

Correct Answer: spanning external fixation with delayed limited open reduction and internal fixation.

Explanation:

Question 61:

Options:

IV antibiotics
Continued oral antibiotics
Removal of the foreign body in the surgical suite with fluoroscopy
Removal of the foreign body in the office under local anesthesia
CT to localize the foreign body

Correct Answer: Removal of the foreign body in the surgical suite with fluoroscopy

Explanation:

Question 62:

Options:

Growth arrest of the distal ulna
Growth arrest of the distal radius
Compartment syndrome
Radioulnar synostosis
Entrapment of the extensor pollicis longus (EPL) tendon

Correct Answer: Growth arrest of the distal ulna

Explanation:

DISCUSSION: The radiographs show a fracture of the distal radius and ulna physis. The most likely complication is growth arrest of the distal ulna. In contradistinction to physis fractures of the radius (growth arrest incidence of less than 5%), the incidence of growth arrest in the ulna is between 30% and 40%. Entrapment of the EPL tendon and cross union between the two bones is extremely rare.
REFERENCES: Vanheest A: Wrist deformities after fracture. Hand Clin 2006;22:113-120.
Cannata G, De Maio F, Mancini F, et al: Physeal fractures of the distal radius and ulna: Long-term prognosis. J Orthop Trauma 2003;17:172-179.
Ray TD, Tessler RH, Dell PC: Traumatic ulnar physeal arrest after distal forearm fractures in children. J Pediatr Orthop 1996;16:195-200.
Aminian A, Schoenecker PL: Premature closure of the distal radial physis after fracture of the distal radial metaphysis. J Pediatr Orthop 1995;15:495-498.

Question 63:

What three structures are considered the primary constraints necessary for elbow stability?

Options:

Coronoid, ulnar part of the lateral collateral ligament, capsule
Capsule, anterior band of the medial collateral ligament, radial head
Radial head, ulnar part of the lateral collateral ligament, capsule
Anterior band of the medial collateral ligament, coronoid, radial head
Ulnar part of the lateral collateral ligament, anterior band of the medial collateral ligament, coronoid

Correct Answer: Ulnar part of the lateral collateral ligament, anterior band of the medial collateral ligament, coronoid

Explanation:

Question 64:

Options:

Abrasive wear
Fatigue wear
Adhesive wear
Adhesive and abrasive wear

Correct Answer: Adhesive and abrasive wear

Explanation:

Question 65:

Options:

Radial nerve injury
Intra-articular loose body causing a block to motion
Lack of active elbow flexion
Recurrent dislocation
Forearm compartment syndrome

Correct Answer: Recurrent dislocation

Explanation:

Question 66:

Options:

Concentric
Isometric
Eccentric
Plyometric

Correct Answer: Eccentric

Explanation:

Question 67:

What is the most prevalent adverse event associated with allogeneic blood transfusion?

Options:

Clerical error leading to transfusion reaction
Anaphylactic reaction
HIV transmission
Hepatitis C transmission
Bacterial contamination leading to sepsis/shock

Correct Answer: Clerical error leading to transfusion reaction

Explanation:

DISCUSSION: Clerical error leading to acute hemolysis and even death occurs in 1:12,000 to 1:50,000 transfusions. Bacterial contamination leading to sepsis/shock occurs in 1:1 million transfusions. HIV transmission is approximately 1:500,000 transfusions and hepatitis C is 1:103,000 transfusions. Anaphylactic reactions occur in 1:150,000 transfusions.
REFERENCES: Aubuchon JP, Birkmeyer JD, Busch MP: Safety of the blood supply in the United States: Opportunities and controversies. Ann Intern Med 1997;127:904-909.
Popovsky MA, Whitaker B, Arnold NL: Severe outcomes of allogeneic and autologous blood donation: Frequency and characterization. Transfusion 1995;35:734-737.

Question 68:

Which of the following structures are found in the anterior tarsal tunnel?

Options:

Extensor hallucis longus, tibialis anterior, extensor digitorum longus, dorsalis pedis artery, deep peroneal nerve
Extensor hallucis longus, tibialis anterior, extensor digitorum longus, dorsalis pedis artery, superficial peroneal nerve
Extensor hallucis longus, tibialis anterior, extensor digitorum longus, dorsalis pedis artery, deep peroneal nerve, superficial peroneal nerve
Extensor hallucis brevis, extensor hallucis longus, extensor digitorum longus, dorsalis pedis artery, deep peroneal nerve
Dorsalis pedis artery, deep peroneal nerve, superficial peroneal nerve

Correct Answer: Extensor hallucis longus, tibialis anterior, extensor digitorum longus, dorsalis pedis artery, deep peroneal nerve

Explanation:

Question 69:

Options:

Metastatic work-up
Physical therapy
Transpedicular biopsy
Thoracotomy with partial resection of the mass
T9 corpectomy with anterior column reconstruction 76.03

Correct Answer: Metastatic work-up

Explanation:

Here is an algorithm from OKU 6 Tumors of the Spine pp 723-736
This question gives you the history, skips right over physical exam and goes into plain films. With this patient’s history of hemoptysis and dyspnea and a lung mass, the next steps in this patients work-up would include the competion of initial work-up, metastatic work-up, then pre-operative planning. Goals of treatment are to 1) protect or restore neurologic function, 2) control pain,

Question 70:

In a patient with a soft-tissue sarcoma treated by wide excision and radiation therapy, the risk of subsequent fracture is probably most influenced by

Options:

location of the sarcoma in the lower extremity.
excision of cortical bone with en bloc resection.
a radiation dose of 60 Gy (6,000 cGy) versus 50 Gy (5,000 cGy).
the addition of adjuvant chemotherapy.
excision of the periosteum.

Correct Answer: excision of cortical bone with en bloc resection.

Explanation:

Question 71:

Options:

Adductor tenotomy
Physical therapy
Observation
Abduction orthosis
Neurologic consultation

Correct Answer: Observation

Explanation:

Question 72:

Options:

observation.
a knee-ankle-foot orthosis.
a medial proximal tibial epiphyseodesis.
a proximal tibial osteotomy.
lateral proximal tibial stapling.

Correct Answer: observation.

Explanation:

Question 73:

Figure 7 shows a sagittal T 1 -weighted MRI scan. What muscle/tendon is identified by the arrow?

Options:

Infraspinatus
Teres minor
Subscapularis
Long head of triceps
Latissimus dorsi

Correct Answer: Teres minor

Explanation:

DISCUSSION: The sagittal T
1
-weighted MRI scan is useful for interpreting the quality of muscle. The arrow is pointing to the teres minor.
REFERENCES: Goutallier D, Postel JM, Gleyze P, et al: Influence of cuff muscle fatty degeneration on anatomic and functional outcomes after simple suture of full-thickness tears.
J Shoulder Elbow Surg 2003;12:550-554.
Agur AM (ed): Grant’s Atlas of Anatomy, ed 9. Baltimore, MD, Lippincott Williams & Wilkins, 1991, p 394.

Question 74:

Options:

Open distal tibial allograft reconstruction
Open reduction and internal fixation (ORIF) with cannulated screws
Arthroscopic coracoid transfer
Arthroscopic repair incorporating the bony component

Correct Answer: Arthroscopic repair incorporating the bony component

Explanation:

Question 75:

Options:

immediate casting with the expectation of a satisfactory correction.
immediate casting with the expectation that surgical correction will be needed.
immediate surgery to correct the deformity.
delayed casting and corrective bracing.
therapeutic and frequent physical therapy to stretch the soft tissues and observe the skin.

Correct Answer: immediate casting with the expectation that surgical correction will be needed.

Explanation:

Question 76:

A 13-year-old girl presents with back pain for 6 months. Figures A and B are SPECT scan and CT images taken at the time of presentation. What is the most likely diagnosis? Review Topic

Options:

Osteoid osteoma
Bone island
Spondylolysis
Osteoblastic metastases
Aneurysmal bone cyst

Correct Answer: Osteoid osteoma

Explanation:

Question 77:

What is the most likely cause of recurrent symptoms following excision of a third web space neuroma?

Options:

Traumatic neuroma tethered by plantar neural branches
Regeneration of the transverse intermetatarsal ligament
Development of an intermetatarsal synovial cyst
Complex regional pain syndrome
Metatarsophalangeal joint synovitis

Correct Answer: Traumatic neuroma tethered by plantar neural branches

Explanation:

Question 78:

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: Correction of the flatfoot deformity

Explanation:

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.
(SBQ13PE.64) A 5-year-old boy presents to clinic for evaluation of bilateral foot deformities shown in Figure 1. He is fully active and has no pain. The feet appear normal when he is sitting on the examination table, and there is supple passive motion at the subtalar joint. Passive ankle dorsiflexion is to neutral with knee in extension and 15 degrees with knee in flexion. What is the most appropriate next step?
Review
Topic
Spine MRI
Standing radiographs of the bilateral feet
Gastrocnemius stretching and nightime use of ankle foot orthosis
Gastrocnemius stretching and use of UCBL orthotic when ambulating
Gastrocnemius stretching
The patient is presenting with bilateral flexible pes planovalgus (or flexbile flatfoot). The most appropriate treatment in patients with a tight heel cord and no pain is gastrocnemius stretching
A flexible flatfoot in a child typically resolves spontaneously. Radiographs are typically indicated when there is pain to rule out other conditions. Treatment for patients without pain includes observation and gastrocnemius stretching. If there is pain, soft arch support or a more rigid UCBL can be used, but orthotics do not change the natural history. In patients with continued tightness in the heel cord despite aggressive stretching, gastrocnemius lengthening may be necessary.
Mosca reviews the management of flexible flatfeet in children and adolescents. He reports that there is no compelling evidence that an arch can be created with use of
orthotics. He proposes the following algorithm: patients with asymptomatic flatfeet are observed; symptomatic flatfeet with tight heel cords undergoing stretching until they become asymptomatic; symptomatic flatfeet with tight heel cords that do not respond to stretching (rare cases) are considered for surgery.
Figure A shows a young a patient with bilateral flatfeet when standing. Incorrect Answers:
abnormalities can seen in patients with cavovarus deformity Answer 2: Radiographs are indicated when there is pain to rule out other conditions. Answer 3: Ankle foot orthoses are not used for pes planovalgus Answer 4: UCBL would be indicated if the patient was having pain.
(SBQ13PE.42) Submuscular bridge plating is appropriate treatment for which of the following?
Review Topic
A 2-month-old female with displaced, spiral, mid-diaphyseal femur fracture
A 26-month-old boy with a displaced spiral mid-diaphyseal femur fracture with
<2cm shortening
A 7-year old boy with a transverse, non-comminuted mid-diaphyseal femur fracture
A 7-year-old boy with a highly comminuted mid-diaphyseal femur fracture
A 15-year-old girl with a displaced butterfly fragmented mid-diaphyseal femur fracture
Submuscular bridge plating is appropriate for length-unstable femur fractures in skeletally immature patients ages 6 years and older.
Traditional plating of diaphyseal femur fractures in children has been abandoned due to the large incision and significant periosteal stripping involved. Submuscular plating with limited incisions and percutaneously applied fixation is a more biologically friendly way to achieve rigid internal fixation in length-unstable fracture patterns. External fixation is another acceptable option for these fractures. Locked plating, on the other hand, provides an 'internal external fixator,' avoids pin site issues and allows rapid mobilization while providing a biologically favorable environment for healing.
Kocher et al. provide the AAOS Clinical Practice Guideline for the treatment of pediatric diaphyseal femur fractures. They concluded that there was insufficient evidence regarding submuscular bridge plating to include it in the guideline.
Flynn et al. review the management of pediatric femoral shaft fractures. The note that
the narrow indications for plating of pediatric femoral fractures are open fractures, multiple trauma, head injury or compartment syndrome in patients less than 12 years old. Plating allows rigid fixation with readily available equipment and allows for rapid mobilization.
Hedequist et al. present a Technical Tricks paper in which they detail their surgical technique for submuscular bridge plating. They recommend this fixation strategy for patients between age 6 and skeletal maturity with comminuted diaphyseal femur fractures that are not easily treated by other methods.
Illustration A shows a preoperative and postoperative radiograph of a comminuted pediatric femur fracture treated with submuscular plating.
Incorrect answers:
(SBQ13PE.88) A 12-month-old boy attends a government regulated childcare center. His parents are called after a fall. Non-accidental trauma has been ruled out. On physical examination the right elbow is swollen and tender. He is unwilling to allow you to move the arm. Radiographs of the elbow are shown in Figure A. What is the orthopaedic management of this injury?
Review Topic
Observation only
Elbow sling for 3 to 4 weeks
Rigid elbow immobilisation for 4 to 5 weeks
Admit for 24-48 hours for continuous intracompartmental pressure measurements
Operative fixation with percutaneous pinning PREFERRED RESPONSE 5
This patient presents with a distal humeral physeal separation. The most appropriate treatment would be closed reduction with internal fixation with percutaneous pins.
Displaced distal humerus physeal separation is typically seen in children under the age of 3 and has a high association with child abuse. The diagnosis can be a difficult as radiographs of a distal humeral physeal separation may be subtle. Often, radiographs show no obvious fracture, but can appear like an elbow dislocation since the secondary ossification centers have not yet developed. MRI or arthrogram can be used to aid in diagnosis.
Shrader et al. reviewed pediatric supracondylar fractures and pediatric physeal elbow fractures. They state the key to diagnosis of distal humerus physeal separation is the assessment is the radial head–capitellum relationship. These injuries should be fixed with closed reduction and smooth wire pinning. An elbow arthrogram may be considered intraoperatively for these patients because of the difficulty visualizing the distal humeral anatomy in children so young.
Skaggs et al. reviewed the diagnosis and management of pediatric elbow fractures. He states that child abuse should be suspected in all cases of elbow fracture when the child is less than 3 years of age and/or the injury pattern occur from a shearing mechanism. The displacement of physeal elbow fractures is almost always posteromedial.
Figure A shows AP and lateral radiographs with posteromedial displacement of the radial and ulnar shafts relative to the distal humerus. This is consistent with distal humeral physeal separation.
Incorrect Answers:

Question 79:

Options:

Quadrigia
Intrinsic tightness
Lumbrical plus deformity
Disruption of the tendon repair

Correct Answer: Quadrigia

Explanation:

Question 80:

Options:

Nonunion
Deep infection
Delayed wound healing
Peroneal tendinitis
Posttraumatic arthritis

Correct Answer: Delayed wound healing

Explanation:

DISCUSSION: Delayed wound healing and wound dehiscence is the most common complication of surgical management of calcaneal fractures through an extensile lateral approach, occurring in up to 25% of patients. Most wounds ultimately heal with local treatment; the deep infection rate is approximately 1% to 4% in closed fractures. Posttraumatic arthritis may develop despite open reduction and internal fixation, but the percentages remain low. Peroneal tendinitis may occur from adhesions within the tendon sheath or from prominent hardware but is relatively uncommon. Nonunion of a calcaneal fracture is rare.
REFERENCES: Sanders RW, Clare MP: Fractures of the calcaneus, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 2, pp 2017-2073.
Sanders RW, Clare MP: Fractures of the calcaneus, in Bucholz RW, Heckman JD,
Court-Brown C (eds): Rockwood and Green’s Fractures in Adults, ed 6. Philadelphia, PA, Lippincott Williams & Wilkins, 2006, vol 2, pp 2293-2336.

Question 81:

Options:

host chondrocytes in the articular cartilage.
subchondral revascularization and fragmentation, without evidence of cartilage degeneration.
an articular surface covered with a pannus of synovial tissue.
radiographically normal thickness of the articular surface, with evidence of cellular debris in the lacuna.
severe degenerative changes in the articular cartilage surface with complete loss of the tidemark.

Correct Answer: radiographically normal thickness of the articular surface, with evidence of cellular debris in the lacuna.

Explanation:

DISCUSSION: Osteoarticular allografts are devoid of host chondrocytes but do contain “mummified” cellular debris left over from donor processing. The cartilage architecture is preserved in the first 2 to 3 years after transplantation. The articular surface is covered with a pannus of fibrocartilage maintaining the joint space radiographically; this pannus later contains islands of fibrocartilage containing host mesenchymal stem cells. Degenerative changes to the joint surface occur earlier and are more severe in joints that are unstable. Only with degenerative changes at the surface is there histologic evidence of subchondral revascularization. Often degenerative changes involving the articular cartilage reach the tidemark, but the tidemark itself remains structurally intact.
REFERENCES: Enneking WF, Campanacci DA: Retrieved human allografts:
A clinicopathological study. J Bone Joint Surg Am 2001;83:971-986.
Enneking WF, Mindell ER: Observations on massive retrieved human allografts.
J Bone Joint Surg Am 1991;73:1123-1142.

Question 82:

Deep posterior compartment

Options:

Anterior tibial artery
Posterior tibial artery
Superficial peroneal nerve
Deep peroneal nerve

Correct Answer: Posterior tibial artery

Explanation:

Question 83:

Which of the following is considered a limitation of the Short Form 36 (SF-36) general health status instrument when applied to musculoskeletal conditions?

Options:

Potential for "ceiling" and "floor" effects
Normative population data have not been attained
Patient's perspective is marginalized or ignored
Must be performed on-site by investigator
Better upper than lower extremity application

Correct Answer: Potential for "ceiling" and "floor" effects

Explanation:

Question 84:

A 3-year-old patient with L3 myelomeningocele has bilateral dislocated hips. Management should consist of

Options:

observation.
bilateral open reduction.
bilateral open reduction and psoas transfers.
bilateral open reduction and external oblique transfers.
bilateral valgus osteotomies.

Correct Answer: observation.

Explanation:

Question 85:

Options:

Bucket-handle tear of the lateral meniscus
Medial meniscus tear
Discoid lateral meniscus
Posterior cruciate ligament tear
Normal MRI of the knee

Correct Answer: Discoid lateral meniscus

Explanation:

Question 86:

Which of the following nerves is most likely responsible for symptoms associated with plantar fasciitis?

Options:

Medial plantar
Medial calcaneal
First branch of lateral plantar
Lateral plantar
Lateral calcaneal

Correct Answer: Lateral calcaneal

Explanation:

Question 87:

- A 16-year-old girl who swims on her high school team reports pain in the shoulder after swimming. History reveals a glenohumeral dislocation at age 14 years while doing the backstroke. Examination shows a positive anterior apprehension sign. Treatment at this time should consist of

Options:

Putti-platt repair
Open Bankart repair
Injection of a subacromial corticosteroid
Arthroscopic transglenoid capsular shift
Rehabilitation of the scapular and rotator cuff muscles

Correct Answer: Rehabilitation of the scapular and rotator cuff muscles

Explanation:

Question 88:

Options:

Radiographs of the hand
Radiographs of the cervical spine
Electrodiagnostic studies of the affected upper extremity
Surgical exploration of the extensor tendon ruptures
MRI of the elbow

Correct Answer: Electrodiagnostic studies of the affected upper extremity

Explanation:

Question 89:

An osteoconductive bone graft material has which of the following properties?

Options:

It contains osteoblastic cells capable of direct bone formation.
It has the ability to stimulate recruitment and differentiation of mesenchymal stem cells.
It has the ability to recruit progenitor cells that can differentiate into osteoblastic cells.
It has the ability to permit ingrowth and sprouting of capillaries and perivascular tissue.
It prevents creeping substitution to allow graft incorporation.

Correct Answer: It has the ability to permit ingrowth and sprouting of capillaries and perivascular tissue.

Explanation:

Question 90:

Options:

Observation
Radiation therapy
Curettage
En bloc excision with stabilization
En bloc excision followed by radiation therapy

Correct Answer: En bloc excision with stabilization

Explanation:

Question 91:

When counseling a patient with hypophosphatemic rickets, which of the following scenarios will always result in a child with the same disorder?

Options:

Female patient who has a female child
Female patient who has a male child
Male patient who has a female child
Male patient who has a male child
Disorder not inherited

Correct Answer: Male patient who has a female child

Explanation:

Question 92:

Options:

A healing osteoporotic compression fracture
A pathologic fracture that is the result of an underlying neoplasm
Nonunion of the fracture with osteonecrosis
Vertebral osteomyelitis
Degeneration of the adjacent intervertebral disk

Correct Answer: Nonunion of the fracture with osteonecrosis

Explanation:

Question 93:

Which of the following methods of meniscal repair has the highest load to failure strength?

Options:

Horizontal suture
Vertical suture
Mulberry knot
T-fix suture
Meniscal arrow

Correct Answer: Vertical suture

Explanation:

Question 94:

Options:

transtibial amputation.
a double upright brace.
dressing changes with platelet-derived growth factor.
tibiocalcaneal arthrodesis.
total ankle arthroplasty.

Correct Answer: tibiocalcaneal arthrodesis.

Explanation:

Question 95:

What is the most likely complication after surgical treatment in this scenario?

Options:

Recurrent instability
Degenerative joint disease
Shoulder stiffness
Axillary nerve injury

Correct Answer: Shoulder stiffness

Explanation:

Question 96:

Options:

Electromyography and nerve conduction velocity studies
MRI
CT
Bone scan
Psychiatric evaluation

Correct Answer: MRI

Explanation:

Question 97:

Which of the following factors is most commonly associated with mechanical failure of a cemented total hip arthroplasty?

Options:

Increased stem offset
Varus position of the stem
Osteoporotic bone
Patient weight of greater than 154 lb
Gender

Correct Answer: Varus position of the stem

Explanation:

Question 98:

Oxidation of polyethylene after sterilization occurs most rapidly when the implant undergoes

Options:

gamma radiation in air.
gamma radiation in nitrogen.
gamma radiation in argon.
gas plasma exposure.
ethylene oxide exposure.

Correct Answer: gamma radiation in air.

Explanation:

Question 99:

Options:

Secondary sarcoma in a pre-existing condition
Angiosarcoma
Metastatic lung carcinoma
Fibrous dysplasia DISCUSSION… The figures show an aggressive destructive lesion in a bone that is already involved with Paget disease, and the pathology shows highly malignant cells. This represents a secondary sarcoma arising in Pagetoid bone. Secondary sarcomas occurring in Pagetic bone include malignant fibrous histiocytoma and chondrosarcomas, but osteosarcomas are the most common malignancy in these patients. Most patients are older than age 60 and have new pain in the setting of known Paget disease. The prognosis is generally poor because this is a very aggressive sarcoma that is difficult to treat in an older population. Wide surgical removal and chemotherapy are most commonly employed. The pathology does not show rudimentary vessels or channels which are expected with angiosarcoma, effectively excluding that diagnosis. A lack of nests or gland formation excludes metastatic lung carcinoma, and the absence of fibrous stroma intermixed with bone islands or “Chinese characters” excludes fibrous dysplasia.

Correct Answer: Secondary sarcoma in a pre-existing condition

Explanation:

Question 100:

A 21-year-old man who was injured in a snowboarding accident 18 months ago now reports wrist pain. An MRI scan is shown in Figure 37. Based on the image findings, what is the most likely diagnosis?

Options:

Preiser’s disease
Scaphoid nonunion and osteonecrosis
Kienbock’s disease
Intraosseous ganglion
Scapholunate dissociation

Correct Answer: Scaphoid nonunion and osteonecrosis

Explanation:

DISCUSSION: The coronal MRI scan of the wrist shows the scaphoid. There is a subtle fracture line with a step-off at the radial surface consistent with a nonunion. The signal intensity is markedly different between the two fragments of the scaphoid. This strongly suggests osteonecrosis. Preiser’s disease is osteonecrosis typically involving most or all of the scaphoid. Kienbock’s disease involves the lunate. Intraosseous ganglia are easily diagnosed on MRI but typically have a fluid-filled area surrounded by denser bone in the periphery. Scapholunate dissociation can be seen on MRI as an injury to the scapholunate ligament and widening of the scapholunate interval, neither of which is seen on this image.
REFERENCE: Perlik PC, Guilford WB: Magnetic resonance imaging to assess vascularity of scaphoid nonunions. J Hand Surg Am 1991;16:479-484.

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

OITE & ABOS Orthopedic Board Prep: Spine, Knee, & Ankle MCQs | Part 10

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 10

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index