+967-774203774 [email protected]
العربية
Part of the Master Guide

Orthopedic Board Review Mock Exam #603: 100 High-Yield MCQs

Orthopedic Board Prep: Set #543 - 100 High-Yield MCQs

27 Apr 2026 100 min read 82 Views
AAOS Pediatrics MCQs: Board Prep Part 3

Key Takeaway

This page provides 100 high-yield Orthopedic Surgery Multiple Choice Questions (MCQs) designed for ABOS, OITE, and FRCS board exam preparation. As Mock Exam Set #543, it helps surgeons assess their knowledge across Pediatrics, Trauma, Spine, and Reconstruction, ensuring comprehensive review and readiness to master their exams.

Comprehensive 100-Question Exam


00:00

Start Quiz

Question 1

A 14-year-old competitive gymnast has had activity-related low back pain for the past month. Examination reveals no pain with forward flexion, but she has some discomfort when resuming an upright position. She also has pain with extension and lateral bending of the spine. The neurologic examination is normal. Popliteal angles measure 20 degrees. AP, lateral, and oblique views of the lumbar spine are negative. What is the next most appropriate step in management?





Explanation

Symptoms of activity-related low back pain, physical findings of pain with extension, lateral bending, and resuming an upright position, and relative hamstring tightness are consistent with spondylolysis. While the initial diagnostic work-up should include plain radiographs of the lumbosacral spine, the findings may be negative because it can take weeks or months for the characteristic changes to become apparent. SPECT has been a useful adjunct in the diagnosis of spondylolysis when plain radiographs are negative. Since the patient's pain is activity related and she is otherwise healthy, evaluation for infection is not indicated. Because the neurologic examination is normal, electromyography, nerve conduction velocity studies, and MRI are not indicated. CT can be used in those instances in which SPECT and bone scans are negative. Ciullo JV, Jackson DW: Pars interarticularis stress reaction, spondylolysis, and spondylolisthesis in gymnasts. Clin Sports Med 1985;4:95-110. Collier BD, Johnson RP, Carrera GF, et al: Painful spondylolysis or spondylolisthesis studied by radiography and single photon emission computed tomography. Radiology 1985;154:207-211. Jackson DW, Wiltse LL, Cirincione RT: Spondylolysis in the female gymnast. Clin Orthop 1976;117:68-73.

References:

Question 2

A 21-year-old football player who sustained a direct blow to the posterior hindfoot while making a cut is unable to bear weight on the injured foot. Examination reveals tenderness and swelling of the great toe metatarsophalangeal (MTP) joint. Radiographs are shown in Figures 9a and 9b. What is the most likely diagnosis?





Explanation

Turf toe occurs in collision and contact sports in which the athlete pushes off to accelerate or change direction and there is hyperextension of the great toe MTP joint. Typically, there is also axial loading of the posterior hindfoot, which increases the hyperextension of the MTP joint. The most common presentation is pain and swelling of the MTP joint and inability to hyperextend the joint without significant symptoms. With significant force, fractures of the sesmoids and plantar soft tissues can occur. The radiographs do not show a dislocation of the great toe MTP joint because it is concentrically located on both radiographs. However, the radiographs show a fracture of the lateral sesamoid or a diastasis of a bipartite lateral sesamoid. The medial sesamoid is also proximal indicating a rupture of the plantar (volar) plate. Therefore, the most likely diagnosis is a fracture of the lateral sesamoid with rupture of the plantar plate leading to proximal migration of the proximal fragment of the lateral sesamoid and the medial sesamoid. Rodeo SA, et al: Diastasis of bipartite sesamoids of the first metatarsophalangeal joint. Foot Ankle 1993;l4:425-434.

References:

Question 3

A 54-year-old woman with idiopathic carpal tunnel syndrome undergoes open carpal tunnel release with a flexor tenosynovectomy. The pathology from the tenosynovium is likely to show





Explanation

The tenosynovium excised at the time of a carpal tunnel release for idiopathic carpal tunnel syndrome rarely shows signs of acute or chronic inflammation. Fibrosis, edema, and vascular sclerosis are the most common histologic findings. A tenosynovectomy with a carpal tunnel release usually is not necessary in the treatment of idiopathic carpal tunnel syndrome. Shum C, Parisien M, Strauch RJ, et al: The role of flexor tenosynovectomy in the operative treatment of carpal tunnel syndrome. J Bone Joint Surg Am 2002;84:221-225. Fuchs PC, Nathan PA, Myers LD: Synovial histology in carpal tunnel syndrome. J Hand Surg Am 1991;16:753-758.

References:

Question 4

Which of the following prognostic indicators is associated with the least favorable outcome for patients newly diagnosed with osteosarcoma?





Explanation

Distant bone metastasis is associated with an extremely poor prognosis for patients with osteosarcoma (5-year survival rate of less than 10%). Most osteosarcomas are high grade and extracompartmental, and approximately half are greater than 8 cm at presentation. The 5-year survival rate for these patients is approximately 70%. Patients with a solitary pulmonary metastasis have a prognosis worse than patients without detectable metastases but not as bad as those with bone metastases. Bielack SS, Kempf-Bielack B, Delling G, et al: Prognostic factors in high-grade osteosarcoma of the extremities or trunk: An analysis of 1,702 patients treated on neoadjuvant cooperative osteosarcoma study group protocols. J Clin Oncol 2002;20:776-790. Heck RK, Stacy GS, Flaherty MJ, et al: A comparison study of staging systems for bone sarcomas. Clin Orthop Relat Res 2003;415:64-71.

References:

Question 5

When 6 weeks of noninvasive nonsurgical management fails to provide relief for a lumbar disk herniation, a trial of epidural steroid injections is likely to yield which of the following results?

Spine Surgery Board Review 2006: High-Yield MCQs (Set 2) - Figure 2





Explanation

Lumbar epidural steroid injections appear to play a role in management of a lumbar disk herniation that has failed to respond to at least 6 weeks of nonsurgical treatment. Approximately 42% to 56% of patients report significant pain relief compared with 92% to 98% of those patients treated with diskectomy. Patients with extruded or sequestered herniations report the greatest and most rapid relief. Similarly, those with well-hydrated disk fragments report rapid relief of symptoms. A smaller percentage of patients report symptom relief compared with those having surgery, but the degree of improvement is similar for both groups and the improvement lasts up to 3 years. Butterman GR: Treatment of lumbar disc herniation: Epidural steroid injection compares with discectomy: A prospective, randomized study. J Bone Joint Surg Am 2004;86:670-679.

References:

Question 6

A 21-year-old hockey player who has recurrent shoulder subluxations undergoes an anterior capsulorrhaphy under general anesthesia, and an interscalene block is used to relieve postoperative pain. At the 1-week follow-up examination, he reports loss of sensation over the lateral region of the shoulder and is unable to actively contract the deltoid muscle. The remainder of the examination is normal. What is the best course of action at this time?





Explanation

The patient has an axillary nerve injury, which is relatively uncommon after surgery for instability. This type of injury generally is the result of a stretch injury rather than transection or a hematoma. Therefore, observation is indicated in the early postoperative period. After approximately 6 weeks, electromyography can be used to confirm and document the point of injury. Interscalene blocks can cause prolonged nerve injury but usually are not limited to the axillary nerve.

References:

Question 7

Figures 21a and 21b show the radiographs of a 22-year-old man who was shot through the abdomen the previous evening. An exploratory laparotomy performed at the time of admission revealed a colon injury. Current examination reveals no neurologic deficits. Management for the spinal injury should include





Explanation

IV broad-spectrum antibiotics should be administered for 7 days. This regimen, when compared to fragment removal or other antibiotic regimens, has been shown to reduce the incidence of spinal infections and reduce the need for metallic fragment removal with perforation of a viscus. Roffi RP, Waters RL, Adkins RH: Gunshot wounds to the spine associated with a perforated viscus. Spine 1989;14:808-811.

References:

Question 8

Treatment of adhesive capsulitis has a high failure rate when the underlying cause is

Shoulder Board Review 2002: High-Yield MCQs (Set 2) - Figure 17





Explanation

Diabetes mellitus has been associated with resistant cases of adhesive capsulitis. With other causes of onset, adhesive capsulitis frequently responds to nonsurgical management such as stretching exercises or, when this fails, manipulation under anesthesia and/or arthroscopic release. Manipulation is rarely successful for the treatment of adhesive capsulitis associated with diabetes mellitus, and arthroscopic release may be preferred. Fisher L, Kurtz A, Shipley M: Association between cheiroarthropathy and frozen shoulder in patients with insulin-dependent diabetes mellitus. Br J Rheumatol 1986;25:141-146. Janda DH, Hawkins RJ: Shoulder manipulation in patients with adhesive capsulitis and diabetes mellitus: A clinical note. J Shoulder Elbow Surg 1993;2:36-38.

References:

Question 9

A 35-year-old woman states that she stepped on a piece of glass 6 months ago and reports numbness and shooting pain along the plantar lateral forefoot. She had previously received steroid injections in the 3 to 4 webspace. Examination reveals mild tenderness along the plantar fascia; no Tinel's sign is noted plantar medially and no Mulder's click is noted distally. An MRI scan is shown in Figure 7. What is the most likely cause of the numbness?

Foot & Ankle 2009 Practice Questions: Set 1 (Solved) - Figure 24





Explanation

The MRI scan reveals a laceration through the abductor hallucis musculature and lateral plantar nerve, producing numbness along its distribution. There is no evidence of a foreign body on the MRI scan. Baxter's nerve, or nerve to the abductor digiti quinti muscle, is the first branch off the lateral plantar nerve and impingement of this nerve typically produces a Tinel's sign along the nerve branch deep to the abductor hallucis muscle. Interdigital neuroma would be suggested by the presence of a Mulder's click. A digital nerve laceration would exhibit isolated numbness more distally. Baxter DE, Pfeffer GB: Treatment of chronic heel pain by surgical release of the first branch of the lateral plantar nerve. Clin Orthop Relat Res 1992;279:229-236.

References:

Question 10

In patients with displaced radial neck fractures treated with open reduction and internal fixation with a plate and screws, the plate must be limited to what surface of the radius to avoid impingement on the proximal ulna?

Anatomy 2008 Practice Questions: Set 1 (Solved) - Figure 22





Explanation

The radial head is covered by cartilage on 360 degrees of its circumference. However, with the normal range of forearm rotation of 160 to 180 degrees, there is a consistent area that is nonarticulating. This area is found by palpation of the radial styloid and Lister's tubercle. The hardware should be kept within a 90-degree arc on the radial head subtended by these two structures. Smith GR, Hotchkiss RN: Radial head and neck fractures: Anatomic guidelines for proper placement of internal fixation. J Shoulder Elbow Surg 1996;5:113-117.

References:

Question 11

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?

Foot & Ankle 2009 Practice Questions: Set 1 (Solved) - Figure 2





Explanation

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. Kitaoka HB, Holiday AD Jr: Metatarsal head resection for bunionette: Long-term followup. Foot Ankle 1991;11:345-349.

References:

Question 12

Figure 47 shows a transverse MRI scan of a patient's left shoulder. The findings reveal which of the following abnormalities?

Anatomy Board Review 2002: High-Yield MCQs (Set 4) - Figure 9





Explanation

The MRI scan shows a defect in the posterior aspect of the humeral head, commonly referred to as a Hill-Sachs lesion. This is an impaction fracture of the humeral head that occurs during anterior shoulder dislocation. The abnormality on this image is an irregularity of the posterior humeral head; the humeral head otherwise has a homogenous appearance. The coracoid, subscapularis, and posterior labrum are normal. Griffin LY (ed): Orthopaedic Knowledge Update: Sports Medicine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 47-63.

References:

Question 13

A 19-year-old rugby player has severe knee pain after being injured in a game 2 weeks ago. Examination reveals a knee effusion, limited motion, and increased 3+ Lachman's test and anterior drawer. There is also increased external rotation at 30 degrees of knee flexion when the patient is placed in the prone position. Based on these findings, which of the following actions would most likely increase the risk of anterior cruciate ligament (ACL) reconstruction failure?





Explanation

The patient has a combined ACL and posterolateral corner injury. Failure to diagnose and treat an injury of the posterolateral corner in a patient who has a tear of the anterior or posterior cruciate ligament can result in failure of the reconstructed cruciate ligament. The tibial external rotation test is best performed with the patient in the prone position. A 10-degree side-to-side difference of external rotation at 30 degrees of knee flexion indicates injury to the posterolateral corner. Acute grade III isolated or combined injuries of the posterolateral corner are best treated early by direct repair or by augmentation or reconstruction of all injured ligaments. Postoperative arthrofibrosis after an ACL reconstruction has been observed with preoperative deficiencies of knee motion. Veltri DM, Warren RF: Posterolateral instability of the knee. J Bone Joint Surg Am 1994;76:460-472.

References:

Question 14

A 7-year-old boy sustained a 2-cm laceration to the anterior aspect of his left knee after falling on a rock. Examination reveals that the joint surface is not visible through the wound. Radiographs show no evidence of a foreign body or free air in the joint. Management should consist of

Pediatrics Board Review 2004: High-Yield MCQs (Set 2) - Figure 30





Explanation

The possibility of an open joint injury should be considered in any patient who has a small periarticular laceration. Failure to promptly diagnose and treat such injuries may lead to septic arthritis. The diagnosis of an open joint is easily made when there is visible communication of the joint through the traumatic wound, or when intra-articular air is present on a radiograph. In the absence of these findings, the diagnosis of an open joint may be established by the saline load test, in which a volume of saline is injected into the joint under sterile conditions. If fluid extravasates through the traumatic wound, the diagnosis of an open joint is established. Voit and associates used a saline load test in 50 patients with periarticular lacerations suggestive of joint penetration. When they compared the clinical prediction of whether or not the laceration had penetrated the joint and the test results, the authors reported a false-positive clinical result in 39% of patients and a false-negative clinical result in 43%. The authors concluded that the saline load test was valuable in evaluating periarticular lacerations. Voit GA, Irvine G, Beals RK: Saline load test for penetration of periarticular lacerations. J Bone Joint Surg Br 1996;78:732-733.

References:

Question 15High Yield

Which of the following studies is considered most sensitive in monitoring a therapeutic response in acute hematogenous osteomyelitis?

General Orthopedics 2026 Practice Questions: Set 17 (Solved) - Figure 24

Explanation

C-reactive protein declines rapidly as the clinical picture improves. Failure of the C-reactive protein to decline after 48 to 72 hours of treatment should indicate that treatment may need to be altered. Blood culture is positive only 50% of the time and will be negative soon after antibiotics are administered, even if treatment is not progressing satisfactorily. WBC count is highly variable and poorly correlated with treatment. The ESR rises rapidly but declines too slowly to guide treatment. Radiographic findings may not change but can take up to 2 weeks to show changes.

References:

Question 16

A 57-year-old man with type I diabetes mellitus has had a tender, erythematous right sternoclavicular joint for the past 2 weeks. Radiographs reveal mild osteolysis without arthritic changes, within normal limits. Management should consist of

Upper Extremity 2005 Practice Questions: Set 1 (Solved) - Figure 28





Explanation

Sternoclavicular joint sepsis is a rare condition that is most often restricted to patients who are immunocompromised, diabetic, or IV drug abusers. Examination commonly reveals a tender, painful, and possibly swollen sternoclavicular joint. If suspicion remains high following a thorough history, physical examination, radiographs, and routine blood tests, joint aspiration should be performed prior to incision and drainage or administration of antibiotics. Bremner RA: Monarticular noninfected subacute arthritis of the sternoclavicular joint. J Bone Joint Surg Br 1959;41:749-753.

References:

Question 17

An acetabular reinforcement cage is most often indicated for which of the following conditions?





Explanation

An acetabular reinforcement cage is required infrequently except when there is pelvic discontinuity in which there is no posterior column support of the acetabular cup. A larger cup inserted with cement and morselized bone graft is an effective technique for contained cavitary and anterior wall defects. Zone 1 osteolysis and a medial wall defect are essentially the same as a contained cavitary defect and can be reconstructed using cementless cups. Berry DJ, Lewallen DG, Hanssen A, Cabanela ME: Pelvic discontinuity in revision total hip arthroplasty. J Bone Joint Surg Am 1999;81:1692-1702.

References:

Question 18

What is the most common organism found following a nail puncture wound through tennis shoes in a host without immunocompromise?





Explanation

The association of a nail puncture wound with a gram-negative infection (Pseudomonas aeruginosa) has been attributed to the local environmental factors in shoes. Osteomyelitis is rare, occurring only in about 1% of patients. Tetanus prophylaxis should be given if it is not up to date. While the remaining organisms listed are periodically involved, they are more common in patients who are immunocompromised or who have diabetes mellitus. Therefore, obtaining a culture of the infected wound is appropriate in such individuals because of the multifactorial nature of the infection. Green NE, Bruno J III: Pseudomonas infections of the foot after puncture wounds. South Med J 1980;73:146-149.

References:

Question 19

A 25-year-old man has had an insidious onset of left hip pain over the past 11 months. A radiograph, coronal MRI scan, and histopathologic specimens are seen in Figures 2a through 2d. What is the most likely diagnosis?





Explanation

Ewing's sarcoma is the second most common primary sarcoma of bone in children and young adults. It is a malignant round cell tumor with uncertain histogenesis. Sheets of uniform small round blue cells with a high nuclear-to-cytoplasm ratio and the absence of osteoid formation differentiate this histologic diagnosis from the other conditions. Immunohistochemical staining and molecular diagnostic studies are useful to verify the diagnosis.

References:

Question 20

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?

Foot & Ankle 2009 Practice Questions: Set 1 (Solved) - Figure 17





Explanation

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. 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.

References:

Question 21

A 33-year-old woman sustains a C6 burst fracture diving into a swimming pool, resulting in a complete spinal cord injury. The canal compromise is shown in Figures 8a and 8b. Functional recovery would be maximized with





Explanation

Although the patient has sustained a complete spinal cord injury, an anterior decompression, even performed late, can gain an additional level of root function. In the quadriplegic patient, this can mean the difference between dependent and independent function. Posterior procedures do not afford adequate access to the retropulsed bony fragments compromising the canal. Bohlman HH, Anderson PA: Anterior decompression and arthrodesis of the cervical spine: Long-term motor improvement. Part I: Improvement in incomplete traumatic quadriparesis. J Bone Joint Surg Am 1992;74:671-682.

References:

Question 22

Retrograde ejaculation is most commonly associated with what surgical approach?





Explanation

Retrograde ejaculation is the sequela of an injury to the superior hypogastric plexus. This structure needs protection, especially during anterior exposure of the lumbosacral junction. Although the superior hypogastric plexus can be injured with anterior or anterolateral spine surgery at any lumbar level, it is most at risk with anterior transperitoneal approaches to the lumbosacral junction. To avoid this complication, the use of monopolar electrocautery should be avoided during deep dissection in this region. The ideal anterior exposure starts with blunt dissection just to the medial aspect of the left common iliac vein sweeping the prevertebral tissues toward the patient's right side. Flynn JC, Price CT: Sexual complications of anterior fusion of the lumbar spine. Spine 1984;9:489-492. Watkins RG (ed): Surgical Approaches to the Spine. New York, NY, Springer-Verlag, 1983, p 107.

References:

Question 23

A 22-year-old man who sustained a Gustilo-Anderson grade IIIC open fracture of the right tibia and fibula was treated with an immediate open transtibial amputation. After two serial debridements, he underwent wound closure with a posterior myocutaneous soft-tissue flap. What is the preferred method of early rehabilitation?

Foot & Ankle Board Review 2006: High-Yield MCQs (Set 2) - Figure 5





Explanation

There is no evidence that early weight bearing enhances ultimate rehabilitation. At the other extreme, weight bearing should not be delayed for a prolonged period of time. In a young, healthy individual, the rigid plaster dressing appears to be the safest method of protecting the wound during the early postoperative period. If the wound appears to be secure, early partial weight bearing can be safely initiated. Burgess EM, Romano RL, Zettl JH: The Management of Lower Extremity Amputations. Washington, DC, US Government Printing Office, 1969, also at: www.prs-research.org.

References:

Question 24

A 14-year-old girl has had progressive heel pain for the past several months. Based on the radiograph, MRI scan, and biopsy specimens shown in Figures 37a through 37d, treatment should include





Explanation

An aneurysmal bone cyst is a benign, locally destructive lesion of bone. Most are seen in patients in the second decade of life. The clinical presentation varies, but most patients have pain, tenderness, swelling, and/or pathologic fracture. Radiographs show a radiolucent lesion sometimes with expansile remodeling of the cortex. MRI best detects the commonly seen fluid-fluid levels associated with this lesion. Histologic findings include blood-filled spaces with bland fibrous connective tissue septa. The stroma has histiocytes, fibroblasts, scattered giant cells, hemosiderin, and occasional inflammatory cells. Treatment of these lesions consists of extended curettage, plus or minus the use of adjuvants (liquid nitrogen, phenol, argon beam coagulation), and finally filling the bone void (allograft or other bone substitute). Gibbs CP Jr, Hefele MC, Peabody TD, et al: Aneurysmal bone cyst of the extremities: Factors related to local recurrence after curettage with a high-speed burr. J Bone Joint Surg Am 1999;81:1671-1678.

References:

Question 25

Figure 30 shows the radiograph of a 38-year-old man who reports persistent pain laterally and plantarly about the fifth metatarsal head. Examination reveals calluses dorsolaterally and plantarly about the fifth metatarsal head. Nonsurgical management has failed to provide relief. Surgical treatment should include

Foot & Ankle 2006 Practice Questions: Set 3 (Solved) - Figure 14





Explanation

The patient has painful lateral and plantar keratoses with metatarsus quintus valgus deformity. This combination of problems is best addressed with an oblique mid-diaphyseal osteotomy that allows the distal metatarsal to be displaced medially and dorsally. Lateral eminence resection alone will not address the painful plantar keratosis. A distal chevron osteotomy has a more limited ability to address the plantar keratosis (if translated medially and slight dorsally). Proximal diaphyseal osteotomies of the fifth metatarsal are associated with an increased risk of delayed union or nonunion secondary to the relative hypovascularity in the proximal diaphysis. Excision of the fifth metatarsal head can result in a floppy fifth toe and transfer metatarsalgia. Coughlin MJ: Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with distal soft tissue repair. Foot Ankle 1991;11:195-203.

References:

Question 26

Figure 11a shows the AP pelvis radiograph of a 25-year-old man who sustained a spinal cord injury 10 years ago. A bone scan and a CT scan are shown in Figures 11b and 11c. To prevent recurrence after resection, management should consist of





Explanation

The studies reveal significant heterotopic ossification that appears to be mature. Following resection, the most reliable way to prevent recurrence is with low-dose external-beam radiation therapy. Bisphosphonate therapy can be considered; however, when terminated, heterotopic bone may reform. Heterotopic ossification is unrelated to the patient's endocrine status and is not associated with any metabolic abnormalities. Moore K, Goss K, Anglen J: Indomethacin versus radiation therapy for prophylaxis against heterotopic ossification in acetabular fracture. J Bone Joint Surg Br 1998;80:259.

References:

Question 27

What is the most important factor in determining recovery after surgical repair of a complete laceration of a nerve at the wrist?





Explanation

All other factors being equal, a patient's age is the most important factor in determining outcome after peripheral nerve injury. Repair of a nerve laceration within the first 2 weeks is generally considered appropriate. Fascicular repair may be of benefit in larger proximal nerves to reapproximate appropriate nerve bundles; distally perineural or epineural repair is sufficient. Use of a fibrin tissue sealant for nerve repair does not result in improved outcomes over suture repair. Nerve conduits have shown promise in digital nerves but do not have proven benefit in larger caliber nerves. Sunderland S: Nerve Injuries and Their Repair: A Critical Appraisal. New York, NY, Churchill Livingstone, 1991. Wilgis ES, Brushart TM: Nerve repair and grafting, in Green DP, Hotchkiss RN (eds): Operative Hand Surgery, ed 3. New York, NY, Churchill Livingstone, 1993, p 1325. Narakas A: The use of fibrin glue in repair of peripheral nerves. Orthop Clin North Am 1988;19:187-199.

References:

Question 28

Osteoclasts originate from which of the following cell types?





Explanation

Osteoclasts originate from the monocyte/macrophage lineage. Fibroblasts and osteoprogenitor cells originate from mesenchymal stem cells and do not form osteoclasts. Plasma cells reside in the bone marrow and are derivatives of the hematopoietic system. Megakaryocytes are also in the bone marrow and synthesize platelets. Zaidi M, Blair HC, Moonga BS, et al: Osteoclastogenesis, bone resorption, and osteoclast-based therapeutics. J Bone Miner Res 2003;18:599-609. Brinker MR: Bone (Section 1), in Miller M (ed): Review of Orthopaedics, ed 2. Philadelphia, PA, WB Saunders, 1996, pp 1-35.

References:

Question 29

Which of the following statements about hoarseness due to vocal cord paralysis after anterior cervical diskectomy and fusion is most accurate?





Explanation

It has been traditionally taught that a left-sided approach to the anterior cervical spine is associated with a lower incidence of injury compared to the right-sided approach. This is due in part to the anatomic differences in the path the recurrent laryngeal nerve (RLN) takes on the right as compared to the left. Both nerves ascend in the tracheoesophageal groove after branching off the vagus nerve in the upper thorax. The left-sided RLN loops around the aortic arch and stays relatively medial as compared to the right-sided RLN which loops around the right subclavian artery and is somewhat more lateral at this point, and therefore is theoretically more vulnerable as it ascends toward the larynx before becoming protected in the tracheoesophageal groove. Furthermore, the variant of a nonrecurrent inferior laryngeal nerve branching directly off the vagus nerve at the level of the midcervical spine is much more common on the right than the left. Despite this reasoning, there has been no clinical evidence to suggest that laterality of approach for anterior cervical surgery makes any difference in the incidence of vocal cord paralysis. Furthermore, two recent studies have shown that the incidence of RLN injury and vocal cord paralysis is equal with either side of approach. Beutler WJ, Sweeney CA, Connolly PJ: Recurrent laryngeal nerve injury with anterior cervical spine surgery risk with laterality of surgical approach. Spine 2001;26:1337-1342.

References:

Question 30

Figure 18a shows the clinical photograph of a 2-year old boy who has a deformity of the right leg. Examination reveals eight cutaneous markings similar to those shown in Figure 18b. Radiographs are shown in Figure 18c. Management should consist of





Explanation

The diagnosis of neurofibromatosis may be based on the presence of at least six cafe-au-lait spots larger than 5 mm in diameter and the osseous lesion shown in Figure 18c. Neurofibromatosis occurs in 50% of patients who have an anterolateral bowing deformity of the tibia, and this bowing may be the first clinical manifestation of this disorder. The patient has anterolateral bowing of the tibia and fibula that warrants concern for a possible fracture and pseudarthrosis; therefore, the limb should be protected in a total contact orthosis to prevent fracture. In contradistinction to posteromedial bowing of the tibia and fibula, spontaneous remodeling of an anterolateral bowing deformity is not expected. Intramedullary nailing or the use of a vascularized fibula is reserved for the treatment of a congenital pseudarthrosis of the tibia. Crawford AH Jr, Bagamery N: Osseous manifestations of neurofibromatosis in childhood. J Pediatr Orthop 1986;6:72-88.

References:

Question 31

A 68-year-old woman who sustained a closed distal tibia fracture 2 years ago was initially treated with an external fixator across the ankle for 12 weeks, followed by intramedullary nailing of the fibula and lag screw fixation of the tibia. She continued to report persistent pain so she was treated with a brace and a bone stimulator. She now reports pain in her ankle. Examination reveals ankle range of motion of 8 degrees of dorsiflexion to 25 degrees of plantar flexion. She is neurovascularly intact. Current radiographs are shown in Figures 9a through 9c. What is the next most appropriate step in management?





Explanation

The patient has a nonunion of the distal fifth of the tibia. The nonunion appears to be oligotrophic, somewhere between atrophic and hypertrophic. Management requires stabilization and stimulation of the local biology, which can be accomplished with open reduction and internal fixation with bone grafting. Bracing or casting does not provide enough stability. Ultrasound bone stimulation has been shown to speed fresh fracture repair but is not indicated in nonunions. The distal segment is too short for intramedullary nailing. A fibular osteotomy alone would increase instability and, even with prolonged casting, would be unlikely to lead to successful repair. Carpenter CA, Jupiter JB: Blade plate reconstruction of metaphyseal nonunion of the tibia. Clin Orthop 1996;332:23-28. Lonner JH, Siliski JM, Jupiter JB, Lhowe DW: Posttraumatic nonunion of the proximal tibial metaphysis. Am J Orthop 1999;28:523-528. Stevenson S: Enhancement of fracture healing with autogenous and allogeneic bone grafts. Clin Orthop 1998;355:S239-S246.

References:

Question 32

Human menisci are made up predominantly of what collagen type?





Explanation

Type I collagen accounts for more than 90% of the total collagen content. Other minor collagens present include types II, III, V, and VI. Mow VC, Arnoczky SP, Jackson DW (eds): Knee Meniscus: Basic and Clinical Foundations. New York, NY, Raven Press, 1992, p 41.

References:

Question 33

Figures 18a and 18b show the radiographs of a patient who has pain with walking. On careful questioning, it is determined that the discomfort occurs at push-off, or when the patient attempts to climb stairs. What nonsurgical option is most likely to ameliorate the symptoms?





Explanation

The patient has a malunion of an attempted open reduction of a Lisfranc dislocation. The pain occurs during the terminal stance phase of gait as load is being transferred from the hindfoot to the forefoot. The bending moment can be best neutralized with shoe modification with a cushioned heel and rocker sole, which best unloads the tarsal-metatarsal junction. Bono CM, Berberian WS: Orthotic devices: Degenerative disorders of the foot and ankle. Foot Ankle Clin 2001;6:329-340.

References:

Question 34

Which of the following muscles has dual innervation?

Anatomy 2008 Practice Questions: Set 3 (Solved) - Figure 9





Explanation

The brachialis muscle typically receives dual innervation. The major portion is innervated by the musculocutaneous nerve. Its inferolateral portion is innervated by the radial nerve. The others listed have single innervation. The anterior approach to the humerus, which requires splitting of the brachialis, capitalizes on this dual innervation.

References:

Question 35

A 43-year-old woman has had pain in the left hip for the past 2 months. A radiograph, CT scan, MRI scan, and biopsy specimens are shown in Figures 16a through 16e. What is the most likely diagnosis?





Explanation

The imaging studies are consistent with a chondrosarcoma. The radiograph shows a radiolucent lesion in the pelvis, and there are stippled calcifications on the CT scan. The histology shows a low-grade cellular hyaline cartilage neoplasm with stellate, occasionally binucleated chondrocytes. Enchondroma has a more benign histologic appearance.

References:

Question 36

The main arterial supply to the humeral head is provided by which of the following arteries?





Explanation

The main arterial supply to the humeral head is provided by the ascending branch of the anterior humeral circumflex artery and its intraosseous continuation, the arcuate artery. There are significant intraosseous anastomoses between the arcuate artery, the posterior humeral circumflex artery through vessels entering the posteromedial aspect of the proximal humerus, the metaphyseal vessels, and the vessels of the greater and lesser tuberosities. Four-part fractures and dissection during exposure affect perfusion of the humeral head. Brooks CH, Revell WJ, Heatley FW: Vascularity of the humeral head after proximal humeral fractures: An anatomical cadaver study. J Bone Joint Surg Br 1993;75:132-136.

References:

Question 37

Figures 14a and 14b show the initial radiographs of an 18-year-old man who fell while snowboarding. Figures 14c and 14d show the radiographs obtained following closed reduction. Examination reveals that the elbow is stable with range of motion. Management should now consist of





Explanation

The initial radiographs reveal a simple elbow dislocation without associated fractures. After successful closed reduction, the range of stability should be assessed. If the elbow is stable, nonsurgical management should consist of a short period of immobilization followed by range-of-motion exercises. Immobilization for more than 3 weeks results in significant elbow stiffness. Surgical repair is indicated for dislocations that are irreducible, have associated fractures, or where stability cannot be maintained with closed treatment. Cohen MS, Hastings H II: Acute elbow dislocations: Evaluation and management. J Am Acad Orthop Surg 1998;6:15-23.

Scientific References

    :

Question 38

Osteonecrosis of the femoral head after intramedullary nailing in children is thought to be the result of injury to the

Anatomy Board Review 2005: High-Yield MCQs (Set 2) - Figure 7





Explanation

All of these are possible explanations for the development of osteonecrosis following intramedullary nailing in children. However, the lateral ascending cervical artery, which supplies the epiphysis, is much more vulnerable to injury in children because it lies in the trochanteric fossa. Buckley SL: Current trends in the treatment of femoral shaft fractures in children and adolescents. Clin Orthop 1997;338:60-73.

References:

Question 39

A 12-year-old girl has had lower back pain for the past 6 months that interferes with her ability to participate in sports. She denies any history of radicular symptoms, sensory changes, or bowel or bladder dysfunction. Examination reveals a shuffling gait, restriction of forward bending, and tight hamstrings. Radiographs show a grade III spondylolisthesis of L5 on S1, with a slip angle of 20 degrees. Management should consist of





Explanation

Indications for surgical treatment of spondylolisthesis include pain and/or progression of deformity. Specifically, surgery is necessary when there is persistent pain or a neurologic deficit that fails to respond to nonsurgical therapy, there is significant slip progression, or the slip is greater than 50%. For patients with mild spondylolisthesis, in situ posterolateral L5-S1 fusion is adequate. In patients with more severe slips (greater than 50%), extension of the fusion to L4 offers better mechanical advantage. Postoperative immobilization may be achieved with instrumentation, casting, or both. In patients with a slip angle of greater than 45 degrees, reduction of the lumbosacral kyphosis with instrumentation or casting is desirable to prevent slip progression. Laminectomy alone is contraindicated in a child. Nerve root decompression is indicated if radiculopathy is present clinically. Seitsalo S, Osterman K, Hyvarinen H, Tallroth K, Schlenzka D, Poussa M: Progression of spondylolisthesis in children and adolescents: A long-term follow-up of 272 patients. Spine 1991;16:417-421.

References:

Question 40

A 12-year-old Little League pitcher reports lateral elbow pain and "catching." Examination reveals painful pronation and supination and tenderness over the lateral elbow. Radiographs are shown in Figures 22a and 22b. Initial management should consist of





Explanation

Osteochondritis of the capitellum is a common problem in young throwing athletes and gymnasts. The mechanism of injury involves lateral compression and axial loading of the capitellum. Repetitive trauma causes ischemia with resultant osteochondral necrosis and sometimes eventual separation. Initial management includes rest for a minimum of 6 weeks; occasionally bracing is used. At long-term follow-up, there is typically an observed radiographic abnormality indicating incomplete healing even in asymptomatic patients. Arthroscopy with in situ drilling is reserved for symptomatic lesions that have an intact articular surface. Lesions with partial separation often require fixation. Lateral column osteotomy is a new investigational procedure designed to relieve lateral compression forces and may be used in salvage cases. Kobayashi K, Burton KJ, Rodner C, et al: Lateral compression injuries in the pediatric elbow: Panner's disease and osteochondritis dissecans of the capitellum. J Am Acad Orthop Surg 2004;12:246-254.

References:

Question 41

A 16-year-old football player sustains a direct blow to the anterior aspect of his flexed right knee. Examination reveals a contusion over the anterior tibial tubercle and a small effusion. MRI scans are shown in Figures 33a through 33c. What is the most likely diagnosis?





Explanation

The MRI scans show disruption of the fibers of the PCL. Patients sustaining an isolated acute PCL injury can present with only minimal discomfort and have full range of motion. When examination reveals a contusion over the tibial tubercle and discomfort with the posterior drawer examination, with or without instability, a possible injury to the PCL should be considered. In acute injuries, the reported accuracy of MRI imaging for diagnosing PCL tears ranges from 96% to 100%. Resnick D, Kang HS: Internal Derangement of Joints: Emphasis on MRI Imaging. Philadelphia, PA, WB Saunders, 1997, pp 699-700. Harner CD, Hoher J: Evaluation and treatment of posterior cruciate ligament injuries. Am J Sports Med 1998;26:471-482.

References:

Question 42

Which of the following describes the correct proximal to distal progression of the annular and cruciform pulleys of the digits?





Explanation

The correct progression of the annular and cruciform pulley in the digits is A1, A2, C1, A3, C2, A4, C3. The two cruciform pulleys are collapsible elements adjacent to the more rigid annular pulleys of the flexor tendon sheath. This arrangement enables unrestricted flexion of the proximal interphalangeal joint. Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics, ed 2. Philadelphia, PA, Lippincott-Raven, 1994, pp 176-186.

References:

Question 43

A newborn has an anterolateral bow of the tibia and a duplication of the great toe. Which of the following conditions will develop as the infant grows?





Explanation

Anterolateral bowing of the tibia is normally associated with congenital pseudarthrosis of the tibia. This, in turn, is associated with neurofibromatosis. Posterior bowing is more benign and usually corrects spontaneously. However, anterolateral bowing also corrects spontaneously, and the limb-length discrepancy may be the only remaining sequela when associated with duplication of the great toe. Lisch nodules and axillary freckling are pathognomonic findings in neurofibromatosis but would not be expected in this patient because this type of tibial deformity is not associated with neurofibromatosis.

References:

Question 44

An excessively large radial styloidectomy poses a risk for wrist instability. What ligament is at greatest risk for injury?





Explanation

The radioscaphocapitate ligament is the most radial of the extrinsic volar ligaments of the wrist. It has a mean attachment to the radius 4 mm from the tip of the radial styloid. Nakamura T, Cooney WP III, Lui WH, et al: Radial styloidectomy: A biomechanical study on the stability of the wrist joint. J Hand Surg Am 2001;26:85-93.

References:

Question 45

The great medullary artery, also known as the Adamkiewicz artery, originates from which of the following arteries?





Explanation

The great medullary artery originates as a direct or indirect branch of the left posterior intercostal artery, usually between T8 and T12. It becomes intradural and crosses over one to three disk spaces before turning to the midline where it anastomoses with the anterior spinal artery. Injury to this artery can result in devastating ischemia of the lower spinal cord. Lu J, Ebraheim NA, Biyani A, Brown JA, Yeasting RA: Vulnerability of great medullary artery. Spine 1996;21:1852-1855.

References:

Question 46

Figures 11a and 11b show the radiographs of a 50-year-old man who was struck by a car. Treatment should consist of





Explanation

The patient has a displaced femoral neck fracture. Although the treatment remains controversial, most clinicians advocate either a closed or open reduction in younger active patients. Achieving an anatomic reduction is necessary to avoid loss of reduction, nonunion, or osteonecrosis. An acceptable reduction may have up to 15 degrees of valgus angulation and 10 degrees of posterior angulation. Parallel multiple screws or pins are the most common method of internal fixation. Prosthetic replacement is generally reserved for older and less active individuals. Callaghan JJ, Dennis DA, Paprosky WG, et al (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1995, pp 97-108.

References:

Question 47

A 40-year-old patient who has a type II odontoid fracture is placed in a halo vest for 12 weeks; however, current radiographs show no evidence of healing. The next most appropriate step in management should consist of

Spine Surgery 2000 Practice Questions: Set 1 (Solved) - Figure 36





Explanation

Because nonsurgical managment has failed and a significant number of type II odontoid fractures will go on to a nonunion, the salvage treatment of choice is posterior fusion at C1-2. Odontoid screws are contraindicated in patients with a chronic nonunion, which this patient has at the end of 3 months. Montesano PX: Anterior and posterior screw and plate techniques used in the cervical spine, in Bridwell KH, DeWald RL (eds): The Textbook of Spinal Surgery, ed 2. Philadelphia, PA, Lippincott-Raven, 1996, vol 2, pp 1743-1761. Bohler J: Anterior stabilization for acute fractures and non-unions of the dens. J Bone Joint Surg Am 1982;64:18-27.

References:

Question 48

Figure 12 shows the radiograph of a 55-year-old man who has severe, painful osteoarthritis of the left hip and is scheduled to undergo a left total hip arthroplasty. History reveals that he underwent a right total hip arthroplasty 5 years ago that remains pain-free. Based on the preoperative radiograph, the patient is at greatest risk for what complication?

Hip Board Review 2001: High-Yield MCQs (Set 2) - Figure 3





Explanation

The patient is at increased risk for limb-length discrepancy because the radiograph shows that the left leg is already longer than the right leg. To restore the proper biomechanics of the left hip, the left leg may have to be lengthened, further increasing the limb-length discrepancy. Intraoperative fracture, deep vein thrombosis, sciatic nerve palsy, and thigh pain are commonly associated with total hip arthroplasty, but the patient is not at increased risk for these complications.

References:

Question 49

What is the most likely late complication associated with cementless total knee replacement?





Explanation

In cementless total knee replacement, the risk of osteolysis is 30% if both components are placed without cement and screws are used for tibial fixation. The risk is 10% when a cemented tibial component is used, and the risk is 0% when both components are cemented. Loss of motion, patellofemoral pain, heterotopic bone formation, and patellar clunk are complications that can occur after cemented or cementless components are placed.

References:

Question 50

Figure 36 shows the radiograph of a 14-year-old boy who has been treated in the past for Perthes' disease with an abduction brace. He now has hip pain that limits his activity, and nonsteroidal anti-inflammatory drugs have failed to provide relief. What is the most appropriate treatment?

Pediatrics Board Review 2007: High-Yield MCQs (Set 4) - Figure 6





Explanation

Several authors have reported good success in relieving pain with shelf acetabuloplasty. This patient's Perthes' disease is in the healed phase; therefore, proximal femoral varus and Salter innominate osteotomies aimed at improving containment are not indicated. The medial one half of the patient's femoral head is markedly deformed, and rotating it into a weight-bearing position with proximal femoral valgus osteotomy is unlikely to relieve pain. Hip arthrodesis can always be performed as a salvage procedure if the shelf acetabuloplasty fails. Daly K, Bruce C, Catterall A: Lateral shelf acetabuloplasty in Perthes' disease: A review of the end of growth. J Bone Joint Surg Br 1999;81:380-384.

References:

Question 51

The gluteus maximus is innervated by which of the following nerves?

Anatomy 2002 Practice Questions: Set 1 (Solved) - Figure 20





Explanation

The inferior gluteal nerve supplies the gluteus maximus muscle. The superior gluteal nerve supplies the gluteus medius, gluteus minimus, and tensor fascia lata muscles. The femoral nerve supplies the quadriceps, sartorius, and pectineus muscles. The pudendal nerve is primarily a sensory nerve.

References:

Question 52

A 51-year-old man sustained an open fracture of his tibia in Korea 42 years ago. An infection developed and it was resolved with surgical treatment. For the past 6 months, an ulcer with mild drainage has developed over the medial tibia. The ulcer is small and there is minimal erythema at the ulcer site. A radiograph and MRI scan are shown in Figures 43a and Figure 43b. Initial cultures show Staphylococcus aureus susceptible to the most appropriate antibiotics. Laboratory studies show an erythrocyte sedimentation rate of 70 mm/h. What is the most appropriate surgical treatment at this time?





Explanation

The patient has chronic tibial osteomyelitis that is due to low virulent bacteria. The history and studies do not suggest the need for an amputation or a free-flap procedure. This is a localized tibial infection that is in a healed bone; there is no need to resect the entire area of the tibia bone around the infection. The most appropriate treatment is curettage, debridement of nonviable bone, and placement of absorbable antibiotic beads, followed by a course of IV antibiotics from 1 to 4 weeks and a 6-week course of oral antibiotics. Studies have shown that in cases of localized osteomyelitis that are of low virulence, as little as 1 week of IV antibiotics followed by 6 weeks of oral antibiotics is successful. Patzakis MJ, Zalavras CG: Chronic posttraumatic osteomyelitis and infected nonunion of the tibia: Current management concepts. J Am Acad Orthop Surg 2005;13:417-427.

References:

Question 53

A 50-year-old man with no history of trauma reports new-onset back pain after doing some yard work the previous day. He reports pain radiating down his leg posteriorly and into the first dorsal web space of his foot. MRI scans are shown in Figures 3a through 3c. What nerve root is affected?





Explanation

The MRI scans clearly show an extruded L4-5 disk that is affecting the L5 nerve root on the left side. In addition, the L5 nerve root has a cutaneous distribution in the first dorsal web space. S1 affects the lateral foot. L4 affects the medial calf.

References:

Question 54

Figures 28a and 28b show the radiographs of a 79-year-old man who has constant knee pain. Prior to performing elective knee replacement surgery, management should include





Explanation

The radiographs show established Paget's disease. Bony expansion is evident, with thickened trabeculae consistent with the disordered bone remodeling process. A reduction of the serum alkaline phosphatase level to 50% of the pretreatment level may reduce pain from Paget's disease, and it is recommended prior to consideration of joint replacement. In elective cases, treatment of Paget's disease should begin at least 6 weeks prior to surgery. The other modalities are not related to the treatment of Paget's disease. Kaplan FS, Singer FS: Paget's disease of bone: Pathophysiology, diagnosis, and management. J Am Acad Orthop Surg 1995;3:336-344. Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 129-184.

References:

Question 55

A 30-year-old man who underwent an anterior lumbar diskectomy and fusion at L4-5 and L5-S1 through an anterior retroperitoneal approach 1 month ago now reports he is unable to obtain and maintain an erection. The most likely cause of this condition is





Explanation

Sexual dysfunction is a common condition after extensive anterior lumbar surgical dissection. Erectile dysfunction usually is nonorganic but may be related to parasympathetic injury. The parasympathetic nerves are deep in the pelvis at the level of S2-3 and S3-4 and usually are not involved in the surgical field for anterior L4-5 and L5-S1 procedures. Retrograde ejaculation is the result of injury to the sympathetic chain on the anterior surface of the major vessels crossing the L4-5 level and at the L5-S1 interspace. Erectile function and orgasm are not affected by sympathetic injury. The pudendal nerve is primarily a somatic nerve and is not located in the surgical field. Flynn JC, Price CT: Sexual complications of anterior fusion of the lumbar spine. Spine 1984;9:489-492.

References:

Question 56

Where is the watershed zone for tarsal navicular vascularity?

Foot & Ankle 2006 Practice Questions: Set 1 (Solved) - Figure 21





Explanation

The central one third has been established as the watershed zone by angiographic studies, and has been borne out in clinical conditions involving the navicular, such as stress fractures and osteonecrosis. These findings account for the susceptibility to injury at this level. Nunley JA, Pfeffer GB, Sanders RW, et al (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 239-242.

References:

Question 57

A 25-year-old semiprofessional football player sustains a hyperextension injury to the left foot. He is unable to bear weight. Examination reveals tenderness along the midfoot with swelling and plantar ecchymosis. Radiographs are negative. What is the next step in evaluation of this patient?

Trauma 2009 Practice Questions: Set 1 (Solved) - Figure 8





Explanation

The patient has a suspected Lisfranc sprain based on the plantar ecchymosis. The first step in diagnosis is a dynamic radiographic study. This should include a physician-assisted midfoot stress examination or standing weight-bearing radiographs to evaluate for displacement. There is no evidence of compartment syndrome, and a bone scan, CT, and MRI are expensive tests that are not warranted. Early JS: Fractures and dislocations of the midfoot and forefoot, in Bucholz R, Heckman JD, Court-Brown CM (eds): Rockwood and Green's Fractures in Adults. Philadelphia, PA, Lippincott Williams and Wilkins, 2006, pp 2337-2400.

References:

Question 58

A 5-year-old boy sustained an elbow injury. Examination in the emergency department reveals that he is unable to flex the interphalangeal joint of his thumb and the distal interphalangeal joint of his index finger. The radial pulse is palpable at the wrist, and sensation is normal throughout the hand. Radiographs are shown in Figures 6a and 6b. In addition to reduction and pinning of the fracture, initial treatment should include





Explanation

The findings are consistent with a neurapraxia of the anterior interosseous branch of the median nerve. This is the most common nerve palsy seen with supracondylar humerus fractures, followed closely by radial nerve palsy. Nearly all cases of neurapraxia following supracondylar humerus fractures resolve spontaneously, and therefore, further diagnostic studies and surgery are not indicated. Cramer KE, Green NE, Devito DP: Incidence of anterior interosseous nerve palsy in supracondylar humerus fractures in children. J Pediatr Orthop 1993;13:502-505.

References:

Question 59

Joint contact pressure in normal or artificial joints can best be minimized by what mechanism?





Explanation

Joint contact pressure is a stress and as such is defined as the load transferred across the joint divided by the contact area between the joint surfaces (the area over which the joint load is distributed). Therefore, any mechanism that decreases the load across the joint (eg, a walking aid) will decrease the stress. Similarly, any mechanism that increases the area over which the load is distributed (eg, using a more conforming set of articular surfaces in a knee joint arthroplasty) will also decrease the stress. Other mechanisms that influence joint contact pressure include the elastic modulus of the materials (cartilage in the case of natural joints and polyethylene in joint arthroplasty) and the thickness of the structures through which the joint loads pass. Bartel DL, Bicknell VL, Wright TM: The effect of conformity, thickness, and material on stresses in UHMWPE components for total joint replacement. J Bone Joint Surg Am 1986;68:1041-1051.

References:

Question 60

Figure 2 shows the radiograph of a 72-year-old woman who reports pain after a fall. History includes several years of increasing thigh pain and limb shortening. Management consisting of an extensive work-up for infection reveals normal laboratory studies, a positive bone scan, and a negative hip aspiration. What is the most likely etiology of this complication?

Hip 2001 Practice Questions: Set 1 (Solved) - Figure 5





Explanation

The patient has a midstem periprosthetic fracture, which commonly results in loosening of the prosthesis. Patients who have a large amount of bone loss may require an allograft with the surgical reconstruction. Although the patient reported a fall, her history is also consistent with preexisting loosening of the prosthesis. Chronic infection has been shown in up to 16% of these fractures; however, the patient's work-up revealed no infection. Garbuz DS, Masri BA, Duncan CP: Periprosthetic fractures of the femur: Principles of prevention and management, in Cannon WD Jr (ed): Instructional Course Lectures 47. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 237-242. Bethea JS III, DeAndrade JR, Fleming LL, Lindenbaum SD, Welch RB: Proximal femoral fractures following total hip arthroplasty. Clin Orthop 1982;170:95-106.

References:

Question 61

A 15-year-old boy with Duchenne muscular dystrophy has a progressive scoliosis that now measures 55 degrees. He is in foster care and is no longer ambulatory. Because posterior spinal fusion with instrumentation is the recommended treatment, the patient participates in a thorough discussion of the risks and benefits of the procedure. However, he refuses the surgery. The physician should now





Explanation

Traditionally, patients have been viewed as ignorant about medical matters and ill-equipped to determine what is in their best interest. This has been especially true for minors. However, recent informed consent policies are now based on the patient's right to self-determination. While most spinal surgeons would agree that spinal fusion improves pulmonary function, sitting balance, and comfort, they would also agree that this comes at considerable risk in a patient with compromised pulmonary function and ultimately, a terminal condition. With increasing frequency, young people older than age 14 years are gaining greater autonomy in decision making about their health care matters. This includes do not resuscitate orders when young patients are terminally ill, as well as in less serious situations. Surgery could be performed with the permission of the legal guardians; however, in this situation it is preferable to follow the patient clinically until he consents to surgery along with the legal guardians. Bracing is contraindicated. Reich WT (ed): Encyclopedia of Bioethics. New York, NY, Simon and Schuster, 1995, pp 1256-1265. Confidential health services for adolescents. Council on Scientific Affairs, American Medical Association. JAMA 1993;269:1420-1424.

References:

Question 62

Figure 3 shows the AP radiograph of a patient with diabetes mellitus who has knee pain. A semiconstrained knee prosthesis was used in this patient to prevent which of the following complications?

Hip & Knee Reconstruction 2007 Practice Questions: Set 1 (Solved) - Figure 8





Explanation

The radiographic appearance of the joint is highly suspicious for neuropathic joint (Charcot's joint). Evidence of bone loss on both the tibial and the femoral sides may necessitate the use of metal and/or bone augments. Patients with a neuropathic joint often have excellent range of motion, and postoperative stiffness is not a problem. The main problem with these patients is instability that occurs secondary to ligamentous laxity. Use of a semiconstrained prosthesis prevents the latter complication. Parvizi J, Marrs J, Morrey BF: Total knee arthroplasty for neuropathic (Charcot) joints. Clin Orthop 2003;416:145-150.

References:

Question 63

A 12-year-old girl sustains an acute injury to the right elbow in a fall. An AP radiograph is shown in Figure 5. Nonsurgical management will most likely result in

Trauma 2000 Practice Questions: Set 1 (Solved) - Figure 10





Explanation

The patient has a significantly displaced medial epicondyle fracture. The only absolute indication for surgical treatment is irreducible incarceration in the joint. Nonsurgical management usually results in a painless nonunion with good elbow function and little elbow instability. Prolonged immobilization should be avoided to prevent stiffness. Tardy ulnar nerve palsy and cubitus varus are not complications of medial epicondyle fractures. Chamber HG, Wilkins KE: Part IV: Apophyseal injuries of the distal humerus, in Rockwood CA Jr, Wilkins KE, Beaty JH (eds): Fractures in Children, ed 4. Philadelphia, PA, Lippincott-Raven, 1996, vol 3, pp 801-812.

References:

Question 64

Figure 41 shows the MRI scan of a 38-year-old weightlifter. What does the arrow on the MRI scan indicate?

Anatomy 2008 Practice Questions: Set 3 (Solved) - Figure 23





Explanation

Pectoralis major ruptures typically occur in avid weightlifters (often on supplements) and typically while bench-pressing. Clinically there is significant discoloration/bruising over the pectoralis and into the axilla. MRI helps confirm the diagnosis and may help determine if the tear is in the muscle belly or at the bone-tendon junction. Bal GK, Basamania CJ: Pectoralis major tendon ruptures: Diagnosis and treatment. Tech Shoulder Elbow Surg 2005;6:128-134.

References:

Question 65

A 36-year-old man has a moderate-sized left paracentral L5-S1 disk herniation with compression of the S1 nerve. Examination will most likely reveal sensory changes at what location?





Explanation

Because the left paracentral L5-S1 disk herniation is compressing the left S1 nerve root, the patient will have numbness along the lateral border and plantar surface of the foot. Numbness along the anterior thigh stopping at the knee is consistent with an L3 radiculopathy. Sensory changes at the dorsum of the foot and great toe normally signify an L5 distribution; the medial leg signifies an L4 distribution. Perianal numbness involves the S2-S5 nerve roots. Wisneski RJ, Garfin SR, Rothman RH, Lutz GE: Lumbar disk disease, in Herkowitz HN, Garfin SR, Balderston RA, Eismont FJ, Bell GR, Wiesel SW (eds): Rothman and Simeone The Spine, ed 4. Philadelphia, PA, WB Saunders, 1999, vol 1, pp 629-634.

References:

Question 66

Figure 1 shows the radiograph of a patient who underwent a total knee revision with a posterior stabilized mobile-bearing prosthesis and now has recurrent knee dislocations. What is the most likely cause?

Hip & Knee Reconstruction 2007 Practice Questions: Set 1 (Solved) - Figure 2





Explanation

The patient has a posterior stabilized total knee revision, and the femoral component has dislocated over the tibial polyethylene cam/post. This usually indicates a loose flexion gap, or "flexion instability." A loose flexion gap can occur due to undersizing of the femoral component, anteriorization of the femoral component, excessive distal augmentation of the distal femur, or collateral ligament insufficiency, especially if combined with posterior capsular insufficiency. Isolated laxity of the extension gap (with a well-balanced flexion gap) causes varus/valgus instability, but it rarely causes the femoral component to "jump" the tibial cam of a posterior stabilized tibial insert. Malrotation of the components may cause patellar instability or a rotational instability of the tibiofemoral joint but should not cause a frank posterior dislocation of the tibia, unless combined with other errors of balancing. Although a mobile-bearing total knee arthroplasty may be more sensitive to errors in balancing than a fixed-bearing total knee arthroplasty, this complication does not reflect a faulty prosthetic design. Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 339-365. Lotke PA, Garino JP: Revision Total Knee Arthroplasty. New York, NY, Lippincott-Raven, 1999, pp 173-186, 227-249.

References:

Question 67

A 51-year-old woman is seen for evaluation of chronic supraspinatus and infraspinatus tendon tears. Three years ago, in an attempted repair the surgeon was unable to repair the supraspinatus and infraspinatus tendon tears. Currently she has a marked amount of pain, reduced range of motion, and weakness. Examination reveals anterosuperior escape. Radiographs show no signs of arthritic changes. You are considering a latissimus dorsi tendon transfer. During the discussion, you mention that





Explanation

Latissimus dorsi tendon transfer is considered a surgical option for treatment in patients with chronic supraspinatus and infraspinatus tendon tears. Preoperative subscapularis function is necessary for good clinical results. Additionally, men with active elevation to shoulder level and active external rotation to 20 degrees have predictably good results. Women with active shoulder elevation limited to below chest level have poor results from this procedure and should not be considered candidates. Postoperatively they lack pain control, active elevation, and active external rotation. Muscular atrophy in the latissimus dorsi does not occur, and glenohumeral arthritic changes frequently develop postoperatively. Gerber C, Maquieira G, Espinosa N: Latissimus dorsi transfer for the treatment of irreparable rotator cuff tears: Factors affecting outcome. J Bone Joint Surg Am 2006;88:113-120.

References:

Question 68

When performing a gastrocnemius recession, what structure should be protected?





Explanation

When performing a gastrocnemius slide at the tendinous portion of the gastrocnemius insertion, the sural nerve and saphenous vein, which tend to run midline posterior at this level, must be protected and retracted laterally. An anatomic study of the sural nerve at this level localized the nerve superficial to the deep fascia overlying the gastrocnemius in 42.5% of the cases; deep to the superficial fascia in 57.5% of the cases, and directly applied to the gastrocnemius tendon in 12.5% of cases. Pinney SJ, Sangeorzan BJ, Hanen ST Jr: Surgical anatomy of the gastrocnemius resection (Strayer procedure). Foot Ankle Int 2004;25:247-250.

References:

Question 69

An 18-year-old lacrosse player is diagnosed with infectious mononucleosis. What is the recommendation for return to play?





Explanation

Infectious mononucleosis commonly affects adolescents and young adults. It is a febrile illness accompanied by acute pharyngitis. Splenomegaly may occur and predispose the athlete to splenic rupture. Splenic rupture has been reported in nonathletes as well as in patients with normal-sized spleens. Clinical evidence supports a return to all sports 4 weeks after the onset of symptoms provided that the spleen has returned to normal size. Auwaerter PG: Infectious mononucleosis: Return to play. Clin Sports Med 2004;23:485-497.

References:

Question 70

A 24-year-old runner who underwent an allograft reconstruction of the anterior cruciate ligament (ACL) 3 years ago now reports anterior knee pain. Examination reveals no swelling or effusion, and the patient has full motion. A Lachman test and a pivot-shift test are negative. Palpation reveals tenderness on the patellar tendon and at the inferior pole of the patella. AP and lateral radiographs are shown in Figures 41a and 41b. Management should consist of





Explanation

The radiographs show tunnel enlargement, which is seen after ACL reconstruction, particularly with allografts. Occasionally, there will be formation of an associated subcutaneous pretibial cyst. It has been proposed that the tunnel enlargement and cyst are the result of incomplete incorporation of allograft tissues within the bone tunnels. There may be residual graft necrosis, allowing synovial fluid to be transmitted through the tunnel to collect in the pretibial area, manifesting as a synovial cyst. In the absence of cyst formation, the presence of tunnel enlargement does not appear to adversely affect the clinical outcome. Based on studies by Fahey and associates, continued tunnel expansion does not occur. Victoroff and associates report good results with curettage and bone grafting of the tibial tunnel if a pretibial cyst is present. Because this patient does not have a pretibial cyst, observation with activity modification is the preferred treatment. Fahey M, Indelicato PA: Bone tunnel enlargement after anterior cruciate ligament replacement. Am J Sports Med 1994;22:410-414.

References:

Question 71

A 21-year-old man with neurofibromatosis and multiple cutaneous neurofibromas has a rapidly enlarging painless mass on his buttock. Examination reveals a nontender, well-defined 6- x 6-cm soft-tissue mass that is deep to the fascia. The best course of action should be to order





Explanation

Patients with neurofibromatosis are at risk for development of soft-tissue sarcomas (most commonly malignant peripheral nerve sheath tumors). Clinical indications of development of a neurofibrosarcoma include a rapidly enlarging soft-tissue mass; therefore, this patient should be considered to have a neurofibrosarcoma until proven otherwise. MRI is superior to CT in characterizing the anatomic location of soft-tissue masses and the signal characteristics of the lesion. Areas of necrosis within the tumor may be apparent on MRI that cannot be appreciated on CT, suggesting a malignant tumor. Local imaging studies of suspected malignant tumors should be performed prior to needle or open biopsy so that the biopsy site can be excised at the time of definitive resection. Additionally, postbiopsy changes may lead to MRI artifacts that alter the interpretation of the MRI. Demas BE, Heelan RT, Lane J, Marcove R, Hajdu S, Brennan MF: Soft-tissue sarcomas of the extremities: Comparison of MR and CT in determining the extent of disease. Am J Roentgenol 1988;150:615-620.

References:

Question 72

In Dupuytren's disease, the retrovascular cord typically displaces the radial proper digital nerve of the ring finger in what direction?





Explanation

Retrovascular cords are common in Dupuytren's disease and commonly require surgical treatment. Nerve injury in Dupuytren's surgery is an infrequent complication that occurs partly because the digital nerves can be displaced from their normal anatomic relationships by retrovascular cords. The nerves are displaced superficially, toward the center of the digit (palmarly and ulnarly). This displacement is typically seen at the level of the metacarpophalangeal joint.

References:

Question 73

Type II collagen in nondiseased adult human articular cartilage has a half-life that is generally





Explanation

Type II collagen in articular cartilage is amazingly stable. This is important to know because matrix homeostasis generally is associated with minimal synthesis and degradation of type II collagen. Passive glycation has a consistent rate and occurs over decades. The relative amount of glycation in cartilage with age has been used as a measure of stability. Also, the rate of racemization of aspartic acid from the L to D form occurs spontaneously at a very slow rate. The relative stability of collagen can be estimated by calculating the percentage of D aspartic acid per dry weight of type II collagen. Maroudas A, Palla G, Gilav E: Racemization of aspartic acid in human articular cartilage. Connect Tissue Res 1992;28:161-169.

References:

Question 74

A 23-year-old soccer player sustains a grade III complete posterior cruciate ligament (PCL) tear after colliding with another player. In reconstructing the PCL, it is optimal to reconstruct the





Explanation

The PCL is a nonisometric structure with nonuniform tension during knee motion, with maximum tension at 90 degrees of flexion. While the posteromedial PCL fibers have been found to be the most isometric, the anterolateral fibers represent the bulk of the ligament. Studies have suggested that anterior placement of the femoral tunnel is superior to placement in an isometric position. The anterolateral bundle tightens as the knee flexes; therefore, it is optimal to tension the graft at 90 degrees of flexion. Harner CD, Xerogeanes JW, Livesay GA, et al: The human posterior cruciate ligament complex: An interdisciplinary study. Ligament morphology and biomechanical evaluation. Am J Sports Med 1995;23:736-745.

References:

Question 75

Figure 16 shows the radiograph of an otherwise healthy 62-year-old woman who fell. Management should consist of

Hip & Knee Reconstruction Board Review 2007: High-Yield MCQs (Set 2) - Figure 3





Explanation

The radiograph reveals that the femoral component is grossly loose as evidenced by disruption of the cement column; therefore, retention of the original components will not yield a successful outcome. A cementless revision is the procedure of choice. A strut graft and/or plate may be added at the surgeon's discretion. A resection arthroplasty would only be considered in a nonambulatory patient. Cemented fixation of the revision component would be problematic given the numerous fracture fragments and the inability to contain the cement. Springer BD, Berry DJ, Lewallen DG: Treatment of periprosthetic fractures following total hip arthroplasty with femoral component revision. J Bone Joint Surg Am 2003;85:2156-2162.

References:

Question 76

What normal tissue has a low signal intensity (appears black) on both T1- and T2-weighted images?

Anatomy 2002 Practice Questions: Set 3 (Solved) - Figure 3





Explanation

Tendons, cortical bone, ligaments, menisci, and fibrous tissue will show low signal intensity (SI) on both T1- and T2-weighted images. Fat-containing tissues, such as subcutaneous fat and bone marrow, will show high SI on T1-weighted images and low SI on T2-weighted images. Tissues with high water content, such as joint fluid, intervertebral disk, and edema, will show low SI on T1-weighted images and high SI on T2-weighted images. Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 65-70.

References:

Question 77

What is the function of the rotator cuff during throwing?

Sports Medicine 2001 Practice Questions: Set 1 (Solved) - Figure 2





Explanation

The coupled action of the rotator cuff prevents superior migration and controls anterior and posterior translation by depressing the humeral head. Poppen NK, Walker PS: Normal and abnormal motion of the shoulder. J Bone Joint Surg Am 1976;58:195-201.

References:

Question 78

A 22-year-old female collegiate javelin thrower has shoulder pain. She notes that her pain is primarily located in the posterior aspect of her shoulder, is exacerbated with throwing, and she experiences maximal tenderness in the extreme cocking phase of the throwing cycle. On examination, she reports deep posterior shoulder pain when the arm is abducted 90 degrees and maximally externally rotated to 110 degrees. This reproduces her symptoms precisely. Shoulder radiographs are normal. What is the most likely diagnosis?





Explanation

The patient has internal impingement. Internal impingement is commonly seen in overhead throwing athletes. When positioned in the extreme cocking phase of the throwing cycle, the posterior glenoid impacts the articular surface of the infraspinatus and posterior fibers of the supraspinatus tendon. This impact can cause partial-thickness rotator cuff tearing and posterosuperior labral lesions. She has no evidence of anterior shoulder instability, and her range of motion is excellent which rules out adhesive capsulitis. Subacromial impingement is identified with anterolateral shoulder pain with internal rotation in the abducted position. A full-thickness rotator cuff tear in a 22-year-old individual would require significant trauma and would likely result in pain at rest and with lifting. Meister K, Buckley B, Batts J: The posterior impingement sign: Diagnosis of rotator cuff and posterior labral tears secondary to internal impingement in overhand athletes. Am J Orthop 2004;33:412-415.

References:

Question 79

An open biopsy specimen of a radiodense distal clavicle lesion in a 12-year-old girl shows chronic polyclonal inflammatory cells without granuloma formation. Laboratory studies show that bacterial, fungal, and acid-fast bacillus cultures are negative. Subsequently, a similar lesion is noted in the fibula. The next most appropriate step in management should consist of





Explanation

The most likely diagnosis is chronic multifocal osteomyelitis. This is a culture-negative polyostotic disease that is most commonly found in young people. The treatment of choice is anti-inflammatory drugs. The pathology does not suggest eosinophilic granuloma. Antiviral therapy, broad-spectrum antibiotics, and surgical resection are not indicated for this disease.

References:

Question 80

What is the most common bacteria cultured from dog and cat bites to the upper extremity?





Explanation

To define bacteria responsible for dog and cat bite infections, a prospective study yielded a median of five bacterial isolates per culture. Pasteurella is most common from both dog bites (50%) and cat bites (75%). Pasteurella canis was the most frequent pathogen of dog bites, and Pasteurella multocida was the most common isolate of cat bites. Other common aerobes included streptococci, staphylococci, moraxella, and neisseria.

References:

Question 81

A 46-year-old woman fell from her bicycle and sustained the injury shown in Figure 24. Which of the following ligaments has been disrupted?

Sports Medicine Board Review 2007: High-Yield MCQs (Set 4) - Figure 5





Explanation

The radiograph shows a type V acromioclavicular joint injury. Type V injuries involve disruption of the acromioclavicular and coracoclavicular ligaments. Type I injuries involve a sprain of the acromioclavicular joint ligaments. Type II injuries involve disruption of the acromioclavicular joint ligaments; the coracoclavicular ligaments are partially injured. Sternoclavicular ligaments stabilize the medial clavicle and the sternum; they are not damaged with acromioclavicular joint dislocations. Fukuda K, Craig EV, An KN, et al: Biomechanical study of the ligamentous system of the acromioclavicular joint. J Bone Joint Surg Am 1986;68:434-439.

References:

Question 82

A 35-year-old runner has pain beneath the second metatarsophalangeal joint. He reports that he has significantly decreased his running distance since the onset of the pain. He denies any history of trauma or injury to the foot. A radiograph is shown in Figure 14. Initial management should consist of

Foot & Ankle 2000 Practice Questions: Set 1 (Solved) - Figure 33





Explanation

The presence of the relatively long second metatarsal, along with the close approximation of the second and third metatarsal heads, are consistent with second metatarsophalangeal tenosynovitis. The hallmark of initial management is conservative. Modalities include taping, nonsteroidal anti-inflammatory drugs, metatarsal pads, and cortisone injections. Trepman and Yeo combined the use of a cortisone injection with a rocker bottom sole. Mizel and Michelson reported their results using an extended rigid steel shank shoe along with a cortisone injection. Trepman E, Yeo SJ: Nonoperative treatment of metatarsophalangeal joint synovitis. Foot Ankle Int 1995;16:771-777.

References:

Question 83

What is the most common arthroscopic finding of internal impingement in an overhead athlete?





Explanation

Internal impingement occurs when the articular side of the supraspinatus abrades against the posterior superior glenoid in the cocking position. Damage may include a posterior labral tear where the contact occurs, not anteriorly as in a Bankart lesion. Biceps fraying and acromion spurs are more commonly seen in extrinsic impingement. Loose bodies may occur from multiple lesions associated with instability and articular cartilage disorders but are uncommon in internal impingement. Jobe CM: Posterior superior impingement of the rotator cuff on the glenoid rim as a cause of shoulder pain in the overhead athlete. Arthroscopy 1993;9:697-699.

References:

Question 84

A 26-year-old man was thrown from a car and sustained the injury seen in Figures 44a and 44b. Nonsurgical management of this injury is recommended. Which of the following factors increases the risk of nonunion?





Explanation

The patient has a displaced comminuted clavicle middle one third fracture from a high-energy mechanism. Recent literature on high-energy clavicular fractures suggests a higher rate of nonunion than previously reported. A nonunion rate of 30% has been reported by Hill and associates when the fracture fragments are displaced more than 1.5 cm. In addition, several patients had neurologic symptoms related to the injury. Robinson and associates reported an increased risk of nonunion in women, elderly patients, comminuted fractures, and injuries with a lack of cortical contact. Hill JM, McGuire MH, Crosby LA: Closed treatment of displaced middle-third fractures of the clavicle gives poor results. J Bone Joint Surg Br 1997;79:537-539. Wick M, Muller EJ, Kollig E: Midshaft fractures of the clavicle with a shortening of more than 2 cm predispose to nonunion. Arch Orthop Trauma Surg 2001;121:207-211.

References:

Question 85

In a patient who has rheumatoid arthritis with acetabular protrusion, what is the best biomechanical position for the cup with respect to the preoperative center of rotation?

Hip 2001 Practice Questions: Set 1 (Solved) - Figure 24





Explanation

Acetabular protrusion in patients with rheumatoid arthritis moves the center of hip rotation medially and posteriorly. Positioning of the acetabular component in a patient with protrusion is best accomplished in the normal (anterior and inferior) position and not in a protruded position. This has been shown both clinically and in a finite-element analysis. Any medial positioning will produce impingement of the prosthesis neck on the rim, and superior placement produces improper hip mechanics. Crowninshield RD, Brand RA, Pedersen DR: A stress analysis of acetabular reconstruction in protrusio acetabuli. J Bone Joint Surg Am 1983;65:495-499.

References:

Question 86

In patients with suspected hepatitis C, which of the following tests is commonly used to confirm the diagnosis after a positive ELISA screening test?





Explanation

The basic diagnostic test for hepatitis C (HCV) is detection of an antibody to epitopes on an enzyme-linked immunosorbent anti-HCV assay (ELISA). The currently used ELISA has high sensitivity (92%) and specificity (95%). False positives, however, still occur. The currently used supplemental test for HCV is strip immunoblot assay, which is based on detection of several HCV epitopes on nitrocellulose paper by antibody-capture techniques. Molecular amplification by PCR technology is very sensitive, but difficult to standardize and susceptible to contamination. Microarray and proteomics are relatively recent molecular techniques used for analysis of genes or proteins, respectively. A Northern blot is used to detect mRNA levels of specific genes but is not used in this situation. de Medina M, Schiff ER: Hepatitis C: Diagnostic assays. Semin Liver Dis 1995;15:33-40.

References:

Question 87

A 30-year-old man has had a 3-day history of severe, incapacitating lower back pain without radiation. He reports improvement with rest. He denies any history of trauma, has no constitutional symptoms, and his neurologic examination is normal. What is the best course of action?





Explanation

There are no red flags in the history or examination to warrant MRI. Limited bed rest (less than 3 days) has been shown to be more beneficial to early recovery compared with prolonged bed rest (more than 7 days). No data support the use of epidural or facet steroid injections for acute low back pain.

References:

Question 88

A patient who sustained a cerebrovascular accident (CVA) 18 months ago has a long-standing spastic adduction contracture of the shoulder with a rigid block to passive external rotation. Significant hygiene problems exist with maceration and continued skin breakdown. Management should consist of





Explanation

Following a CVA, the muscular imbalance often leads to a fixed contracture of the shoulder in adduction, internal rotation, and flexion. The responsible muscles include the pectoralis major, subscapularis, teres major, and latissimus dorsi. If stretching cannot produce enough improvement for axillary hygiene, then surgery is an option. If the shoulder resists external rotation during examination with the arm at the side, as in this patient, then the subscapularis is spastic and contributing to the deformity as well and needs to be released along with the pectoralis. Phenol nerve blocks are most effective and best given within 6 months of the initial CVA to be effective. Lidocaine blocks may be helpful in determining whether a deformity is caused by a fixed soft-tissue contracture or by spasticity but play no role once the contracture is present. The modified L'Episcopo procedure is indicated in patients with contracture secondary to brachial plexus birth palsies. Braun RM, Botte MJ: Treatment of shoulder deformity in acquired spasticity. Clin Orthop 1999;368:54-65.

References:

Question 89

A 72-year-old man injured his right shoulder after tripping over a chair leg. Radiographs obtained in the emergency department reveal an isolated anterior dislocation. After successful closed reduction, the patient has recurrent anterior instability and is unable to elevate the arm. What is the most likely cause of the recurrent instability?

Upper Extremity 2005 Practice Questions: Set 1 (Solved) - Figure 24





Explanation

A rotator cuff tear is the most common cause of recurrent instability following a first-time dislocation in patients older than age 40 years. Dislocations occur through a posterior mechanism rather than by an isolated labral avulsion or a Bankart lesion as seen in younger patients. Nevaiser RJ, Nevaiser TJ: Recurrent instability of the shoulder after age 40. J Shoulder Elbow Surg 1995;4:416-418.

References:

Question 90

Posterior lumbar spine arthrodesis may be associated with adjacent segment degeneration cephalad or caudad to the fusion segment. Which of the following is the predicted rate of symptomatic degeneration at an adjacent segment warranting either decompression and/or arthrodesis at mid-range follow-up (5-10 years) after lumbar fusion?





Explanation

The rate of symptomatic degeneration at an adjacent segment warranting either decompression or arthrodesis was predicted to be 16.5% at 5 years and 36.1% at 10 years based on a Kaplan-Meier analysis.

References:

Question 91

A 35-year-old man sustained a 1-inch stab incision in his proximal forearm while trying to use a screwdriver 2 weeks ago. The laceration was routinely closed, and no problems about the incision site were noted. He now reports that he has been unable to straighten his fingers or thumb completely since the injury. Clinical photographs shown in Figures 30a and 30b show the man passively flexing the wrist. What is the most appropriate management?





Explanation

The clinical photographs indicate that the tenodesis effect of digit flexion with passive wrist extension and digit extension with passive wrist flexion is intact, indicating no discontinuity of the extensor or flexor tendons. The most likely injury is a laceration of the posterior interosseous nerve.

References:

Question 92

Which of the following statements best describes synovial fluid?





Explanation

Synovial tissue is composed of vascularized connective tissue that lacks a basement membrane. Two cell types (type A and type B) are present: type B cells produce synovial fluid. Synovial fluid is made of hyaluronic acid and lubricin, proteinases,and collagenases. It is an ultrafiltrate of blood plasma added to fluid produced by the synovial membrane. It does not contain erythrocytes, clotting factors, or hemoglobin. It lubricates articular cartilage and provides nourishment via diffusion. Synovial fluid exhibits non-Newtonian flow characteristics. The viscosity coefficient is not a constant, the fluid is not linearly viscous, and its viscosity increases as the shear rate decreases.

References:

Question 93

A 29-year-old man reports severe knee instability and popliteal pain. History reveals that he had polio of the left lower extremity as a child and has been brace-free his entire life. Examination reveals that he walks with 40 degrees of knee hyperextension and has a fixed ankle equinus deformity of 30 degrees. He has no active motors about the knee or ankle. Which of the following methods will provide knee stability and pain relief?





Explanation

The ankle equinus allows the patient to keep his weight-bearing line anterior to the axis of the hyperextended knee joint. With time, pain has developed because of continued stretching and now incompetence of the posterior capsule of the knee joint. Several soft-tissue and bony procedures have been designed to provide knee stability in this situation; however, the results have been either short-lived or inconsistent. Tenodeses, capsular plications, and bony blocks have had limited success and generally fail over time. Current orthotic technology makes soft-tissue release and orthotic control the most predictable option. To decrease the hyperextension moment on the knee joint, the ankle deformity also must be corrected. The most predictable method of achieving stability and diminished pain during walking is with soft-tissue release of the ankle and a knee-ankle-foot orthosis with a locked ankle and drop-lock knee joint.

References:

Question 94

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

Pediatrics 2001 Practice Questions: Set 3 (Solved) - Figure 26





Explanation

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

References:

Question 95

Figure 11 shows the lateral radiograph of a 16-year-old boy who has been unable to participate in sports activities because of pain in the anterior aspect of the knee. He states that the pain is aching in nature and is located in the region of the tibial tuberosity. He denies having joint effusion or symptoms of instability. Management should consist of

Pediatrics 2001 Practice Questions: Set 1 (Solved) - Figure 19





Explanation

The prognosis for most patients with Osgood-Schlatter disease is good. When the secondary ossification center unites with the main body of the tibial tubercle, the patellar tendon has a more rigid anchor, and heterotopic ossification and its associated reaction often become quiescent. However, even after closure of the growth plates, some patients have persistent symptoms. Excision of the ossicle and prominence of the tibial tuberosity decompresses the patellar tendon and allows most patients to resume sports activities. Nonsurgical modalities are ineffective. Better results have been reported after excision than after drilling of the tubercle. Excision of the ossicle is not indicated prior to skeletal maturity because symptoms will resolve in most patients when the secondary ossification center unites. Flowers MJ, Bhadreshwar DR: Tibial tuberosity excision for symptomatic Osgood-Schlatter disease. J Pediatr Orthop 1995;15:292-297.

References:

Question 96

Figures 3a and 3b show the MRI scans of a patient with neck pain. What is the most likely diagnosis?





Explanation

Muliple neurofibromas result in marked foraminal enlargement as seen on the sagittal MRI scan. Collagen disorders leading to dural ectasia may show similar enlargement, but none of these is listed as a possible answer. Kim HW, Weinstein SL: Spine update: The management of scoliosis in neurofibromatosis. Spine 1997;22:2770-2776.

References:

Question 97

Factors contributing to an increased risk of hip fracture include reduced bone mineral density of the femoral neck, cognitive status of the individual, and





Explanation

The etiology of hip fractures in the elderly is multifactorial, and intervention and prevention can occur at multiple points. Events leading to hip fracture from a fall include fall initiation (during which the individual's neuromuscular status, cognitive status, and vision come into play along with environmental hazards); fall descent (fall direction toward the side being the most influential, energy content of the fall, and fall height, along with muscle activity of the muscles of the thigh); impact (impact location, soft-tissue attenuation such as from trochanteric padding or from overlying fat, impact surface, and muscle activity); and the structural capacity of the femur (bone mineral density, bone geometry, and bone architecture). Hayes and Myers noted that striking the ground in a stiff state with the trunk muscles contracted actually increased the peak impact force, whereas falling in a relaxed state actually reduced peak impact force. Flexion of the trunk at impact had no bearing on the impact force. Direction of the fall was important; falls to the side, not forward, were associated with an increased risk of hip fracture. Increased muscle activity about the hip is thought to be associated with spontaneous fractures of the hip and may actually account for up to 25% of hip fractures; however, it is not related to fractures resulting from a fall.

References:

Question 98

Figures 35a and 35b show the radiographs of a 20-year-old man who is unable to rotate his dominant forearm. Examination reveals that the arm is fixed in supination. To regain motion, management should consist of





Explanation

The patient has a proximal synostosis; therefore, resection of the synostosis is considered the best option to regain motion. While forearm osteotomy can place the hand in a more functional position, rotation will not be restored. Proximal radial excision can provide forearm rotation; however, this procedure is reserved for patients who have a proximal radioulnar synostosis that is too extensive to allow a safe resection, involves the articular surface, and is associated with an anatomic deformity. Motion will not be restored with dynamic splinting. Kamineni S, Maritz NG, Morrey BF: Proximal radial resection for posttraumatic radioulnar synostosis: A new technique to improve forearm rotation. J Bone Joint Surg Am 2002;84:745-751.

References:

Question 99

What is the most common indication for revision following unconstrained elbow arthroplasty?

Upper Extremity 2005 Practice Questions: Set 1 (Solved) - Figure 6





Explanation

Instability following unconstrained elbow arthroplasty occurs in 10% of patients. Subluxation is twice as common as frank dislocation; however, only 20% of these patients undergo revision. Instability following unconstrained elbow arthroplasty can be caused by component malposition or ligament insufficiency. King GJ, Itoi E, Niebur GL, et al: Motion and laxity of the capitellocondylar total elbow prosthesis. J Bone Joint Surg Am 1994;76:1000-1008.

References:

Question 100

Which of the following is an important factor in performing a proper biopsy?

Basic Science 2008 Practice Questions: Set 3 (Solved) - Figure 6





Explanation

There are a number of important technical details in performing a biopsy. Incisions should always be longitudinal in the extremity. Good hemostasis is important in avoiding contamination from hematoma. The approach should avoid neurovascular structures, and go through a single muscle belly when possible. Although a frozen section should be obtained to ensure adequate viable tissue has been obtained, definitive diagnosis is not necessary at the time of the frozen section. Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 197-215.

References:

🔗 Read the comprehensive guide: 100 Random Orthopedic MCQs for Board Prep (2026 Update)

Previous Chapter100 Orthopedic Surgery MCQs: ABOS, OITE, FRCS Board Review … Next Chapter Orthopedic Board Review MCQs: Set 210 (ABOS, OITE, FRCS Exa…
Clinic OS
Medically Verified Content by
Prof. Clinic OS
Consultant Orthopedic & Spine Surgeon
Chapter Index
Back to Master Guide