Orthopedic Board Review MCQs: OITE & AAOS Part 159

About This Board Review Set

This is Part 159 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

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

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Two distinct learning modes are available:

Study Mode — After selecting an answer, you immediately see whether you are correct or incorrect, together with a full clinical explanation and literature references.
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Pro Tip: Use keyboard shortcuts A–E to select options, F to flag a question for review, and Enter to jump to the next unanswered question.

Topics Covered in Part 159

This module focuses heavily on: Dislocation, Fracture, Infection, Knee, Shoulder.

Sample Questions from This Set

Sample Question 1: A relative contraindication for anteromedial tibial tubercle transfer for patellar instability is arthrosis in what portion of the patella?...

Sample Question 2: A 13-year-old girl with Down syndrome has bilateral chronic patellar dislocations. She denies knee pain. She is able to straighten her knees and walks with a symmetric but awkward gait. She does not flex her knees in midstance. Examination ...

Sample Question 3: A 32-year-old patient reports progressively increasing pain and stiffness after undergoing arthroscopic shoulder stabilization 1 year ago. The stabilization procedure was a Bankart repair with anchor fixation and supplemented with the heat ...

Sample Question 4: What is the most common location for localized pigmented villonodular synovitis (PVNS) to occur?...

Sample Question 5: 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...

Why Active MCQ Practice Works

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

Comprehensive 100-Question Exam

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Question 1

A relative contraindication for anteromedial tibial tubercle transfer for patellar instability is arthrosis in what portion of the patella?

Explanation

DISCUSSION: Anteromedial displacement of the tibial tubercle unloads the distal and lateral facets of the patella and shifts the forces to the proximal and medial facets. Therefore, if findings indicate arthrosis predominately in the medial and proximal areas of the patella, this is considered a relative contraindication because it may accentuate arthritic symptoms.
REFERENCES: Fulkerson JP: Anteromedialization of the tibial tuberosity for patellofemoral malalignment. Clin Orthop 1983;177:176-181.
Bellemans J, Cauwenberghs F, Witvrouw E, et al: Anteromedial tibial tubercle transfer in patients with chronic anterior knee pain and a subluxation-type patellar malalignment. Am J Sports Med 1997;25:375-381.
Kuroda R, Kambic H, Valdevit A, et al: Articular cartilage contact pressure after tibial tuberosity transfer: A cadaveric study. Am J Sports Med 2001;29:403-409.

Question 2

A 13-year-old girl with Down syndrome has bilateral chronic patellar dislocations. She denies knee pain. She is able to straighten her knees and walks with a symmetric but awkward gait. She does not flex her knees in midstance. Examination reveals that the patellae cannot be brought into a reduced position. Management should consist of

Explanation

DISCUSSION: Chronic dislocation of the patella is occasionally seen in patients with Down syndrome. In early childhood, patellar realignment may restore stability of the patellae. In later childhood, bony changes in the patellar groove interfere with stability, even if surgical realignment is performed. Realignment can also lead to increased knee pain postoperatively. In asymptomatic patients who are able to extend their knees, continued observation is the management of choice.
REFERENCES: Dugdale TW, Renshaw TS: Instability of the patellofemoral joint in Down syndrome. J Bone Joint Surg Am 1986;68:405-413.
Mendez AA, Keret D, MacEwen GD: Treatment of patellofemoral instability in Down’s syndrome. Clin Orthop 1988;234:148-158.

Question 3

A 32-year-old patient reports progressively increasing pain and stiffness after undergoing arthroscopic shoulder stabilization 1 year ago. The stabilization procedure was a Bankart repair with anchor fixation and supplemented with the heat probe. Radiographs are shown in Figures 45a and 45b. What is the most likely diagnosis?

Explanation

DISCUSSION: Postshoulder stabilization chondrolysis is a rare but devastating complication. It has been implicated with the use of the radiofrequency heat probe in some patients.
REFERENCES: Levine WN, Clark AM Jr, D’Alessandro DF, et al: Chondrolysis following arthroscopic thermal capsulorrhaphy to treat shoulder instability: A report of two cases. J Bone Joint Surg Am 2005;87:616-621.
Petty DH, Jazrawi LM, Estrada LS, et al: Glenohumeral chondrolysis after shoulder arthroscopy: Case reports and review of the literature. Am J Sports Med 2004;32:509-515.

Question 4

What is the most common location for localized pigmented villonodular synovitis (PVNS) to occur?

Explanation

DISCUSSION: Localized PVNS is a form of the disease in which synovial proliferation is restricted to one area of a joint and causes the formation of a small mass-like lesion. The true incidence of this is unknown but is probably less common than the diffuse form of the disease. PVNS presents as a usually painful discrete mass. The anterior compartment of the knee is the most common location.
REFERENCES: Tyler WK, Vidal AF, Williams RJ, et al: Pigmented villonodular synovitis.

J Am Acad Orthop Surg 2006;14:376-385.
Kim SJ, Shin SJ, Choi NH, et al: Arthroscopic treatment for localized pigmented villonodular synovitis of the knee. Clin Orthop Relat Res 2000;379:224-230.

Question 5

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

DISCUSSION: 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.
REFERENCES: 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.
Beals RK, Bryant RE: The treatment of chronic open osteomyelitis of the tibia in adults.

Clin Orthop Relat Res 2005;433:212-217.

Question 6

What strategy has proven most effective in preventing transmission of methicillin-resistant Staphylococcus aureus among teammates? Review Topic

Explanation

Prevention is the key to controlling infections among athletes. Proper hygiene is critical and should mandate showering, hand washing, wearing breathable clothing, and shower sandals. The sharing of towels or athletic equipment should be forbidden. Daily skin surveillance by athletes, trainers, and physicians can allow early recognition and treatment initiation during the early stages of infection, limiting risk for further transmission. Additionally, disinfecting shared equipment, covering lesions with occlusive dressing during sporting activity, and restricting the contact activities of infected athletes can limit risk for an infectious outbreak among teammates.

Question 7

Figures 24a through 24c show the coronal T 1 -weighted, T 2 -weighted fat-saturated, and T 1 -weighted fat-saturated gadolinium MRI scans of the proximal thigh of a 52-year-old woman who reports a mass in the medial thigh and groin area. She notes that the fullness has grown in size over the course of many months. Based on these findings, what is the most likely diagnosis?

Explanation

DISCUSSION: The images show a complex, lobular lesion of the thigh that has signal characteristics that follow fat. The size of the lesion, the areas of stranding within the mass, along with mild uptake on the gadolinium sequences and the mild edema within the lesion on the T₂-weighted image make liposarcoma the most likely diagnosis and simple intramuscular lipoma far less likely. All other diagnoses listed would not follow fat characteristics shown on the MRI sequences.
REFERENCE: Sanders TG, Parsons TW: Radiographic imaging of musculoskeletal neoplasia. Cancer Control 2001;8:221-231.

Question 8

Which of the following is considered a specific advantage of using COX-2 inhibitors over COX-1 inhibitors?

Explanation

DISCUSSION: Inflammation is mediated through two isoforms of cyclooxygenase that convert arachidonic acid to prostaglandins. Selectivity, but not specificity, is one of the unique characteristics of this process that has been able to provide more protection from the effects of gastric mucosal alterations using the COX-2 selective inhibitors. The use of COX-1 selective inhibitors is associated with side effects such as ulcerative conditions and platelet interference, both of which have been difficult to control in the past until the advent of the COX-2 inhibitors. PGE₂ inhibition by COX-1 in the intestinal track can then be bypassed, thereby reducing ulceration complications associated with use of nonsteroidal anti-inflammatory drugs.
REFERENCES: Lane JM: Anti-inflammatory medications: Selective COX-2 inhibitors. J Am Acad Orthop Surg 2002;10:75-78.
Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002.
Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000.

Question 9

A 35-year-old male has a closed mid-shaft tibia fracture following a skiing accident. You have recommended intramedullary nailing of the tibia. What is the most common complication he must be advised about?

Explanation

DISCUSSION: Chronic anterior knee pain at the insertion site is the most common frequently reported complication of closed nailing of a tibial shaft fracture. A high incidence of knee pain has been associated with IM nailing. The etiology of anterior knee pain remains unclear. It had been previously thought that the incidence of pain is higher when the nail was inserted by a patellar tendon-spliting approach versus a paratendon approach. According to the Keating paper, insertion of the nail through the patella tendon was associated with a higher incidence of knee pain compared to the paratendon site of nail insertion (77% and 50% respectively). Toivanen et al. investigated this question when the group randomized fifty patients with a tibial shaft fracture requiring intramedullary nailing equally to treatment with paratendinous or transtendinous nailing. Fourteen (67%) of the twenty-one patients treated with transtendinous nailing reported anterior knee pain at the final evaluation. Of these fourteen patients, thirteen were mildly to severely impaired by the pain. Fifteen (71%) of the twenty-one patients treated with paratendinous nailing reported anterior knee pain, and ten of the fifteen were impaired by the pain. The Lysholm, Tegner, and Iowa knee scoring systems; muscle-strength measurements; and functional tests showed no significant differences between the two groups. Compared with a transpatellar tendon approach, a paratendinous approach for nail insertion does not reduce the prevalence of chronic anterior knee pain or functional impairment by a clinically relevant amount after intramedullary nailing of a tibial shaft fracture.

Question 10

A previously healthy 35-year-old man was involved in a rollover motor vehicle accident 2 days ago. He was placed in a semi-rigid cervical orthosis. He now reports mostly axial neck pain with attempted range of motion. Examination reveals the mechanical neck pain but no obvious neurologic deficits. AP, flexion, and extension radiographs are shown in Figures 10a through 10c, and sagittal and coronal CT scans are shown in Figures 10d and 10e. What is the most appropriate management at this time?

Explanation

DISCUSSION: Odontoid fractures can be classified based on the anatomic position of the fracture within the dens itself. Type I is an oblique fracture through the upper part of the odontoid process. Type II is a fracture that occurs at the base of the odontoid as it attaches to the body of C2; type III occurs when the fracture line extends through the body of the axis. Type 1 fractures typically can be treated nonsurgically with 6 to 8 weeks of immobilization with a semi-rigid cervical orthosis. Nondisplaced, deep type III fractures generally are treated with skeletal halo fixation. Deep, displaced, and angled type III fractures can be treated with closed reduction and skeletal halo fixation. Shallow type III fractures are sometimes amenable to anterior odontoid screw fixation. Type II fractures can be managed nonsurgically or surgically. Treatment options include halo immobilization, internal fixation (odontoid screw fixation), and posterior atlantoaxial arthrodesis. Management with the halo vest usually is considered if the initial dens displacement is less than 6 mm, the reduction is performed within 1 week of the injury and is able to be maintained, and the patient is younger than age 60 years. Halo vest immobilization can lead to a healing rate of more than 90%. Posterior surgical fusion techniques provide high fusion success rates but do so at the expense of cervical rotation. Up to 50% of rotation is lost with these techniques. Anterior odontoid single screw fixation is often tolerated better than skeletal halo fixation and also is noted to preserve the normal rotation at C1/C2. Studies have shown less of a malunion and nonunion rate in the treatment of type II odontoid fractures with anterior odontoid screw fixation. Osteoporosis, short neck and barrel-chested anatomy, and fractures that are more than 4 weeks old preclude anterior odontoid fixation.
REFERENCES: Shilpakar S, McLaughlin MR, Haid RW Jr, et al: Management of acute odontoid fractures: Operative techniques and complication avoidance. Neurosurg Focus 2000;8:e3.
Subach BR, Morone MA, Haid RW Jr, et al: Management of acute odontoid fractures with single-screw anterior fixation. Neurosurgery 1999;45:812-819.
Fountas KN, Kapsalaki EZ, Karampelas I, et al: Results of long-term follow-up in patients undergoing anterior screw fixation for type II and rostral type III odontoid fractures. Spine 2005;30:661-669.

Question 11

You are interested in learning a new technique for minimally invasive total knee arthroplasty. The Keyhole Genuflex system seems appealing to you because the instrumentation comes with wireless controls. What is an acceptable arrangement to learn more about this system?

Explanation

Both the American Academy of Orthopaedic Surgeons (AAOS) and AdvaMed, the medical device manufacturer's trade organization, have written guidelines that address potential conflicts of interest regarding interactions between physicians and manufacturer's representatives when it comes to patients' best interest. The AAOS feels that the orthopaedic profession exists for the primary purpose of caring for the patient and that the physician-patient relationship is the central focus of all ethical concerns. When an orthopaedic surgeon receives anything of significant value from industry, a potential conflict of interest exists. The AAOS believes that it is acceptable for industry to provide financial and other support to orthopaedic surgeons if such support has significant educational value and has the purpose of improving patient care. All dealings between orthopaedic surgeons and industry should benefit the patient and be able to withstand public scrutiny. A gift of any kind from industry should in no way influence the orthopaedic surgeon in determining the most appropriate treatment for his or her patient. Orthopaedic surgeons should not accept gifts or other financial support with conditions attached. Subsidies by industry to underwrite the costs of educational events where CME credits are provided can contribute to the improvement of patient care and are acceptable. A corporate subsidy received by the conference's sponsor is acceptable; however, direct industry reimbursement for an orthopaedic surgeon to attend a CME educational event is not appropriate. Special circumstances may arise in which orthopaedic surgeons may be required to learn new surgical techniques demonstrated by an expert or to review new implants or other devices on-site. In these circumstances, reimbursement for expenses may be appropriate.

Question 12

All of the following have been shown to negatively affect clinical outcomes in treating displaced acetabular fractures, EXCEPT:

Explanation

DISCUSSION: Negative outcome factors have been shown to include: increasing patient age, time from injury to surgery (>3 weeks), intraoperative complications, femoral head bone or cartilage injury, and fracture reduction > 1-2mm from anatomic. Choice of surgical approach has not been shown to affect patient outcomes.
The referenced study by Matta evaluated outcomes of displaced acetabular fractures. The overall clinical result was excellent for 104 hips (40 per cent), good for ninety-five (36 per cent), fair for twenty-one (8 per cent), and poor for forty-two (16 per cent). The clinical result was related closely to the radiographic result. These findings indicate that in many patients who have a complex acetabular fracture the hip joint can be preserved and post-traumatic osteoarthrosis can be avoided if an anatomical reduction is achieved.

Question 13

Which of the following nerves is susceptible to entrapment near the calcaneal attachment site of the plantar fascia and can mimic or co-exist with plantar fasciitis?

Explanation

DISCUSSION: The first branch of the lateral plantar nerve is susceptible to entrapment beneath the deep fascia of the adductor hallucis muscle adjacent to the calcaneal attachment of the plantar fascia. This can be a cause of chronic heel pain. Additionally, the nerve is vulnerable to injury by a blind dissection in releasing the plantar fascia. The dorsal cutaneous branch of the superficial peroneal nerve supplies sensation to the dorsum of the foot. The medial calcaneal branch of the posterior tibial nerve lies in the subcutaneous tissues and innervates the skin of the heel. It is vulnerable to injury from skin incisions on the medial side of the heel. The lateral branch of the medial plantar nerve forms the second and third common digital nerves. Entrapment of the proper medial plantar nerve can occur at the master knot of Henry. This is well distal to the calcaneal attachment of the plantar fascia, and the pain usually radiates more distally in the arch, separate from heel pain. The communicating branch of the fourth common digital nerve crosses to the third common digital nerve. Therefore, the third common digital nerve receives supply from both the lateral and medial plantar nerves. This dual supply has been implicated in the increased incidence of digital neuroma of the third common digital nerve.
REFERENCES: Bordelon RL: Heel pain, in Mann RA, Coughlin MJ (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, CV Mosby, 1993, pp 837-857.
Mann RA, Baxter DE: Diseases of the nerves, in Mann RA, Coughlin MJ (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, CV Mosby, 1993, pp 543-574.
Baxter DE: The heel in sport. Clin Sports Med 1994;13:683-693.

Question 14

A college athlete has a knee injury requiring surgery. He has acne, gynecomastia, and well-developed muscles related to the use of anabolic steroids. What association with steroid use is concerning for surgery and anesthesia?

Explanation

DISCUSSION: Anabolic steroids increase procoagulant factors VII and IX and thromboxane, all of which lead to hypercoagulability which would decrease bleeding time. Liver function is usually upregulated as oral steroids induce hepatic enzymes and patients are therefore less sensitive to anesthetic agents. Anabolic steroids have a mineralocorticoid effect and users frequently use diuretics to mask this effect. Both can lead to fluid and electrolyte imbalances. Cardiovascular effects include hypertension, left ventricular hypertrophy, impaired diastolic filling, and thrombosis. Large muscle mass and high calorie intake lead to high ventilatory requirements caused by increased oxygen consumption and carbon dioxide production. Anabolic steroids have no effect on the spleen.
REFERENCES: Kam PC, Yarrow M: Anabolic steroid abuse: Physiological and anesthetic considerations. Anaesthesia 2005;60:685-692.
Ansell JE, Tiarks C, Fairchild VK: Coagulation abnormalities associated with the use of anabolic steroids. Am Heart J 1993;125:367-371.

Question 15

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

Explanation

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

Question 16

Which of the following statements best describes synovial fluid?

Explanation

DISCUSSION: 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.
REFERENCE: Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science: Biology and Biomechanics of the Musculoskeletal System, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 443-470.

Question 17

A 40-year-old man sustains a fracture-dislocation of C4-5. Examination reveals no motor or sensory function below the C5 level. All extremities are areflexic. The bulbocavernosus reflex is absent. The prognosis for this patient’s neurologic recovery can be best determined by

Explanation

DISCUSSION: The patient has spinal shock. Steroid administration and MRI are appropriate therapeutic and diagnostic procedures. Myelography with CT is of little value unless there is an unusual skeletal variant. Spinal cord-evoked potentials have no value. The best method to determine the patient’s neurologic recovery is repeated physical examinations over the first 48 to 72 hours.
REFERENCES: Spivak JM, Connolly PF (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 183-184.
Herkowitz HN, Garfin SR, Eismont FJ: Rothman-Simone The Spine, ed 5. Philadelphia, PA, Saunders Elsevier, 2006, pp 1185-1194.

Question 18

In addition to the radiographic features seen in Figures 49a and 49b, this patient will most likely have which of the following findings?

Explanation

DISCUSSION: The radiographs show the characteristic features of osteopetrosis. The condition results from defective resorption of immature bone by osteoclasts. There are three distinct clinical forms: (1) infantile-malignant, which is autosomal recessive and fatal in the first few years of life if untreated; (2) intermediate autosomal recessive; and (3) autosomal dominant. These conditions do not follow a malignant course, and patients have normal life expectancy with orthopaedic problems and anemia. In the malignant form, the clinical features include frequent fractures, macrocephaly, progressive deafness and blindness, hepatosplenomegaly, and severe anemia beginning in early infancy or in utero. Deafness and blindness are generally thought to represent effects of pressure on nerves and usually occur later in life. The anemia is caused by encroachment of bone on marrow, resulting in obliteration, and the hepatosplenomegaly is caused by compensatory extramedullary hematopoiesis. Dental caries and abscesses, as well as osteomyelitis of the mandible, are also seen. Most patients have normal intelligence. Treatment of the malignant form includes high dose 1,25 dihydroxy vitamin D with a low-calcium diet to stimulate bone resorption, not because there are vitamin deficiencies. Bone marrow transplant has also been successful.
REFERENCES: Herring JA: Tachdjian’s Pediatric Orthopedics, ed 4. Philadelphia, PA, WB Saunders, 2002, p 1550.
Zaleske DJ: Metabolic and endocrine abnormalities, in Morrissy RT, Weinstein SL (eds): Lovell and Winter’s Pediatric Orthopaedics, ed 5. Philadelphia, PA, Lippincott Williams and Wilkins, 2001, pp 212-214.
Kaplan FS, August CS, Fallon MD, et al: Successful treatment of infantile malignant osteopetrosis by bone-marrow transplantation: A case report. J Bone Joint Surg Am 1988;70:617-623.

Question 19

Early postoperative infections following primary total hip arthroplasty are most likely caused by which organism?

Explanation

DISCUSSION:
S aureus is the most common organism cultured in early (fewer than 4 weeks postoperative) periprosthetic infections. Methicillin-resistant S aureus is becoming a more common pathogen in certain patient populations. B hemolytic Streptococcus and some gram-negative infections can also be found in early postoperative infections. S epidermidis, S viridans, and P acnes are more commonly found in late (more
than 4 weeks postoperative) infections.

Question 20

Figure 37 shows the T2-weighted MRI scan of the hip joint. What structure is labeled A?

Explanation

DISCUSSION: The obturator internus originates on the obturator membrane and adjacent bone, including the quadrilateral plate, and exits the lesser sciatic notch to insert on the posterior medial greater trochanter. The structure labeled C is the pectineus, B is the sartorius, and D is the gluteus medius.
REFERENCES: Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, pp 145-150, 324.
Anderson JE (ed): Grant’s Atlas of Anatomy, ed 7. Baltimore, MD, Williams & Wilkins, 1978, plate 4-46.

Question 21

A 15-year-old girl who plays high school basketball has had worsening forefoot pain and swelling that is aggravated by activity for the past 5 weeks. She denies any history of an injury. Examination reveals no deformities. A radiograph is shown in Figure 38. Initial management should consist of

Explanation

DISCUSSION: Freiberg’s infraction is believed to be an osteochondrosis of the second metatarsal head. It is the only osteochondrosis that has a predilection for females. The typical patient is an athletically active adolescent female. The radiograph shows stage II disease wherein reossification is occurring; it is at this time that the second metatarsal head is most susceptible to deformation. Therefore, initial management should consist of a short leg

walking cast.
REFERENCE: Mann RA, Coughlin MJ: Keratotic disorders of the plantar skin, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 413-415.

Question 22

A 39-year-old male falls off his bicycle and complains of neck pain and tingling in his fingers. Trauma series radiographs are seen in Figures A and B. Which of the following is likely to be true? Review Topic

Explanation

This patient has ankylosing spondylitis (AS). HLA-B27 is positive in 90% of patients with this disease. This tends to occur in younger patients (as opposed to DISH, which happens in older male patients).
Cervical spine fractures are not uncommon in ankylosing spondylitis because of osteoporosis and the long lever arm from fused vertebrae. They commonly occur because of hyperextension of the cervical spine (usually C5-7) and have a high rate of neurologic injury. AS fractures have a higher rate of neurologic injury than DISH fractures. Posterior decompression and stabilization with long constructs is necessary
Whang et al. reviewed spine injuries in 12 patients with AS and 18 patients with DISH. Most injuries involved C5-C7. Patients with AS were more likely to have severe neurologic injury (41% ASIA A) than DISH (44% ASIA E). There was 81% good-excellent outcome and 4 deaths related to halo vest use.
Caron et al. reviewed spine fractures in patients with ankylosing spine disorders (AS and DISH). AS patients were younger than DISH patients. Spinal cord injury was present in 58%. Surgery was performed on 67% and comprised instrumentation 3 levels above/below the injury. Mortality correlated with age. Mortality was 32%.
Westerveld et al. performed a systematic review on spine injuries in ankylosing spinal disorders. Most patients had sustained low energy trauma (fall from sitting/standing). In DISH, most fractures were through the vertebral body. In AS, vertebral body fractures equaled those through the disc. Surgery was performed for neurological deterioration, unstable fracture and the presence of an epidural hematoma.
Figure A shows a hyperextension injury at C6-7 (Type I, disc or Type IV,anterior disc, posterior body) cervical spine fracture in ankylosis spondylitis. Visible radiographic characteristics include osteopenia, bamboo spine, marginal syndesmophytes and ossfication of the disc space. Figure B is a chest radiograph showing thoracic syndesmophytes consistent with ankylosing spondylitis. Figure C shows bilateral sacroilitis and hip joint space narrowing typical of ankylosing spondylitis. Illustration A shows the Caron classification of spine fractures in ankylosing spondylitis (Type A, disc injury; Type B, body injury; Type C, anterior body, posterior disc injury; Type D, anterior disc, posterior body injury). Illustration B shows the difference between the marginal osteophytes of AS and nonmarginal osteophytes of DISH in the cervical spine. If you have osteophytes that are building up, and project out anterior to the anterior cortex of the vertebral bodies, like "flowing wax" it is DISH.
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Question 23

At the time of revision knee arthroplasty, a surgeon performs a rectus snip to gain exposure to the knee. When compared with a standard parapatellar approach, what is the expected outcome?

Explanation

DISCUSSION:
Rectus snip during total knee arthroplasty has no effect on motion or strength at long-term follow-up. It has not been associated with extensor mechanism lag.

Question 24

A 16-year-old boy sustains a twisting injury to the left knee while wrestling. MRI scans are shown in Figures 22a through 22c. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI scans show a displaced bucket-handle medial meniscus tear that can be visualized on coronal, sagittal, and axial views. The sagittal view shows the typical “double posterior cruciate ligament sign,” in which the low-signal bucket-handle fragment parallels the normal low-signal posterior cruciate ligament. The coronal and axial images both show the displaced medial meniscus in the notch.
REFERENCES: Sanders TG, Miller MD: A systematic approach to magnetic resonance imaging interpretation of sports medicine injuries of the knee. Am J Sports Med 2005;33:131-148.
Miller TT: Magnetic resonance imaging of the knee, in Insall JN, Scott WN (eds): Surgery of the Knee, ed 4. Philadelphia, PA, Churchill Livingstone, 2006, vol 1, pp 201-224.

Question 25

A 4-month-old infant is unable to flex her elbow as a result of an obstetrical brachial plexus palsy. This most likely illustrates a predominate injury to what structure? Review Topic

Explanation

Erb’s palsy is the most common form of obstetrical plexus palsy resulting in C5, C6, or upper trunk deficits. This causes loss of shoulder abduction and elbow flexion. The biceps muscle and the brachialis muscles are predominately responsible for flexion of the elbow. Each of these muscles is innervated by individual branches of the musculocutaneous nerve which are supplied predominately by axons from the C6 nerve root and the upper trunk of the brachial plexus

Question 26

Based on the MR arthrogram of the elbow shown in Figure 8, which of the following structures is torn?

Explanation

DISCUSSION: Based on the MR arthrogram in which gadolinium (bright on T1-weighted images) was injected into the joint space prior to imaging, the study shows a tear of the anterior band of the ulnar collateral ligament (UCL). The disruption in the distal end of the UCL is outlined by contrast. A small collection of contrast extravasation into the flexor musculature further confirms the presence of a tear. The UCL has a broad-based attachment on the medial epicondyle and has a pointed or tapered attachment distally on the ulna. Most UCL tears occur distally at the ulnar (coronoid) attachment.
MR arthrography provides improved sensitivity compared to conventional MRI, without contrast, for the detection of UCL pathology, particularly in the subacute or chronic setting. After the soft-tissue edema and joint fluid associated with the injury have resolved, the torn end of the ligament may lie in contact with its adjacent attachment and create a false-negative appearance. In this patient, a noncontrasted MR arthrogram showed no tear, yet the tear is apparent with intra-articular contrast and distention. MR arthrography of the elbow also may be useful in detecting intra-articular bodies or in evaluation for loose osteochondral fragments or flaps.
REFERENCES: Morrey BF: Acute and chronic instability of the elbow. J Am Acad Orthop Surg 1996;4:117-128.
Resnick D, Kang HS (eds): Internal Derangements of Joints: Emphasis on MR Imaging. Philadelphia, PA, WB Saunders, 1997, pp 200-210.

Question 27

A 34-year-old man sustained a tibial fracture in a motorcycle accident. What perioperative variable is associated with the greatest relative risk for reoperation to achieve bone union?

Explanation

DISCUSSION: In a recent analysis of 200 patients with tibial fractures, Bhandari and associates attempted to identify variables that were predictive of reoperation. The variables in the study were type of injury (fracture pattern), degree of open injury, mechanism of injury, cortical bone contact, postoperative complications, polytrauma, anti-inflammatory drug use, nail insertion technique (reamed versus nonreamed), smoking history, alcohol use, diabetes mellitus, peripheral vascular disease, age, disability status pre-injury, gender, surgeon, time to surgery, steroid use, phenytoin use, antibiotic use, anticoagulant use, and type of fixation used. Three variables were statistically significant predictors of reoperation to achieve bone union in the first postinjury year: transverse fracture pattern, open fracture, and cortical contact of 50% or less. Using these three variables, four reoperation risk groups were identified based on the number of these three variables present: 0, 1, 2, or 3. The risk for reoperation was 0%, 18%, 47%, and 94%, respectively. The authors concluded that these statistics can provide prognostic information to patients and help identify those high-risk patients where early intervention to achieve union is indicated. In addition, the data highlights the significance of achieving cortical contact at the time of initial fixation.
REFERENCE: Bhandari M, Tornetta P III, Sprague S, et al: Predictors of reoperation following operative management of fractures of the tibial shaft. J Orthop Trauma 2003;17:353-361.

Question 28

Figures 4a and 4b are the radiographs of an isolated injury. What is the next most appropriate step in management?

Explanation

Successful treatment of a pilon fractures requires a complete understanding of the fracture configuration. This information is not available using radiographs alone; therefore, CT is used to define the fracture anatomy but only after stabilization and distraction of the fracture via external fixation. MRI does not adequately show the detail of the bone fragments. Immediate ORIF is contraindicated because of the high rate of soft-tissue complications with this treatment regimen, whereas closed treatment has a high rate of poor outcomes because of arthritis. Delayed ORIF is the recommended treatment, but this occurs after temporary stabilization and CT scanning.

Question 29

Figure 1 shows the radiograph of a 71-year-old man who has had increasing pain and weakness in his shoulder for the past 3 years. Nonsurgical management has failed to provide relief. Examination shows 130 degrees of active forward flexion and intact external rotation strength. During surgery, a 1- x 1-cm rotator cuff tear involving the supraspinatus is encountered. Treatment should include

Explanation

DISCUSSION: Given the size of the rotator cuff tear, it is likely to be repaired; therefore, the treatment of choice is a total shoulder replacement with rotator cuff repair. Severe rotator cuff insufficiency can lead to early glenoid failure because of superior instability, and glenoid resurfacing should be avoided in those instances.
REFERENCES: Boyd AD Jr, Thomas WH, Scott RD, Sledge CB, Thornhill TS: Total shoulder arthroplasty versus hemiarthroplasty: Indications for glenoid resurfacing. J Arthroplasty 1990;5:329-336.
Arntz CT, Jackins S, Matsen FA III: Prosthetic replacement of the shoulder for treatment of defects in the rotator cuff and surface of the glenohumeral joint. J Bone Joint Surg Am 1993;75:485-491.

Question 30

Radiating pain associated with a posterolateral thoracic disk herniation typically follows what pattern?

Explanation

DISCUSSION: Although symptomatic thoracic disk herniations can affect more caudal structures, even to the point of paralysis, the pattern of radiating pain has been described as either following the dermatomal band around the chest or feeling to the patient as if the pain passes straight anteriorly to the chest wall.
REFERENCE: Skubic JW, Kostuik JP: Thoracic pain syndromes and thoracic disc herniation, in Frymoyer JW (ed): The Adult Spine: Principles and Practice. New York, NY, Raven Press, 1991, pp 1443-1464.

Question 31

Clinical evidence suggests that grafts for replacing a torn anterior cruciate ligament often stretch after surgery. What is the most probable mechanism for this behavior?

Explanation

DISCUSSION: The stretching of the graft occurs over time as the graft is loaded. Time-dependent deformation under load is called creep and is common in viscoelastic materials such as ligament tissue. Creep can occur under both static and cyclic load conditions; time-dependent deformation will occur as long as load is applied to the tissue. Similarly, when a graft is initially tensioned to a given deformation at surgery, the load generated in the graft will decrease over time; this behavior is called stress relaxation and also is indicative of a viscoelastic material. Water content may affect the viscoelastic properties by changing the friction between collagen fibers, but studies have shown little difference in water content between grafts and normal ligaments. Fatigue failures may manifest themselves through damage to the ligament tissue, but this would require higher loads than are routinely experienced by grafts. Elastic stretch is recoverable and, therefore, does not contribute to a permanent stretch. Similarly, gross failure at the attachment would not cause a stretch, but rather a catastrophic instantaneous instability.
REFERENCES: Boorman RS, Thornton GM, Shrive NG, et al: Ligament grafts become more susceptible to creep within days after surgery. Acta Orthop Scand 2002;73:568-574.
Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science: Biology and Biomechanics of the Musculoskeletal System, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 596-609.
Lu L, Kaufman KR, Yaszemski MJ: Biomechanics, in Einhorn TA, O’Keefe RJ,

Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 32

A 46-year-old woman who was involved in a motor vehicle accident reports a 4-month history of right-sided lower back pain and pain radiating into the right thigh. The patient underwent an extensive 3-month course of physical therapy and now is dependent on narcotic medication for pain control. Epidural injection therapy has failed to improve her symptoms. Examination is significant for weakness of hip flexion in the seated position and for decreased sensation to light touch in the medial anterior thigh region. Straight leg raise is negative, but the femoral stretch test reproduces anterior thigh pain. A CT myelogram image, at L3-L4, is shown in Figure 3. What is the most appropriate management at this time?

Explanation

DISCUSSION: The CT scan reveals a right-sided lateral disk protrusion at L3-4 that has been symptomatic for more than 4 months despite appropriate nonsurgical management. Relative surgical indications include persistent radiculopathy despite an adequate trial of nonsurgical management, recurrent episodes of sciatica, persistent motor deficit with tension signs and pain, and pseudoclaudication caused by underlying stenosis. Whereas studies have shown improvement in patients with sciatica from a lumbar disk herniation treated either nonsurgically or surgically, those undergoing surgical treatment had an overall greater improvement of symptoms.
REFERENCES: Weinstein JN, Lurie JD, Tosteson TD, et al: Surgical vs nonoperative treatment for lumbar disk herniation: The Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA 2006;296:2451-2459.
Yorimitsu E, Chiba K, Toyama Y, et al: Long-term outcomes of standard discectomy for lumbar disc herniation: A follow-up study of more than 10 years. Spine 2001;26:652-657.

Question 33

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

DISCUSSION: 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.
REFERENCES: Flynn JC, Price CT: Sexual complications of anterior fusion of the lumbar spine. Spine 1984;9:489-492.
Johnson RM, McGuire EJ: Urogenital complications of anterior approaches to the lumbar spine. Clin Orthop 1981;154:114-118.

Question 34

Bioabsorbable polymers are used in a wide range of orthopaedic devices, including anchors, staples, pins, plates, and screws. What is the primary drawback for bioabsorbable implants?

Explanation

DISCUSSION: A number of bioabsorbable polymers are used in orthopaedic applications, and all have in common reports of foreign body reactions, which occur in more than 50% of patients in some series. In general, the high cost of these polymers is offset by the elimination of a second surgery to remove the implant. Bioabsorbable polymers are low strength in comparison to metallic alloys but of sufficient strength for many orthopaedic applications. The elastic modulus is not as high as many other orthopaedic biomaterials, making them suitable for applications where lower stiffness is an asset.
REFERENCES: Ambrose CG, Clanton TO: Bioabsorbable implants: Review of clinical experience in orthopedic surgery. Ann Biomed Eng 2004;32:171-177.
Bergsma JE, de Bruijn WC, Rozema FR, et al: Late degradation tissue response to poly

(L-lactide) bone plates and screws. Biomaterials 1995;16:25-31.

Question 35

Figures 86a through 86c are the radiographs and biopsy specimen of a 14-year-old boy who has had left knee pain for 4 weeks. What is the most likely diagnosis?

Explanation

Question 36

A 40-year-old woman reports the atraumatic onset of severe knee pain and swelling after undergoing an uncomplicated elective cholecystectomy 1 week ago. She denies any history of diabetes mellitus or HIV but has had occasional episodes of mild knee pain and swelling that have always responded to nonsteroidal anti-inflammatory drugs. Radiographs are shown in Figures 5a and 5b. A knee aspiration yields a WBC count of 35,000/mm 3 . The aspirate should also yield which of the following findings?

Explanation

DISCUSSION: The radiographs reveal chondrocalcinosis of the menisci. This is caused by calcium pyrophosphate crystals, which are weakly positive birefringent rhomboid-shaped crystals. Frequently, this condition is asymptomatic; however, routine abdominal surgery may cause precipitation of these crystals and pain. Gout, which is caused by strongly negative birefringent needle-shaped sodium urate crystals, is not associated with chondrocalcinosis and is rare in younger women. Gross blood is uncommon without trauma. Infection is not likely in a healthy patient who underwent uncomplicated surgery.
REFERENCES: Fisseler-Eckhoff A, Muller KM: Arthroscopy and chondrocalcinosis. Arthroscopy 1992;8:98-104.
Hough AJ Jr, Webber RJ: Pathology of the meniscus. Clin Orthop 1990;252:32-40.

Question 37

Changes to the properties of ultra-high molecular weight polyethylene with increasing irradiation dose include improved

Explanation

DISCUSSION: Increased irradiation doses cause a decrease in the mechanical properties of the polyethylene, resulting in a decrease in ultimate tensile strength, fracture toughness, and resistance to crack propagation.
Irradiation leads to the production of free radicals, requiring a step in the manufacturing process (melting, annealing, vitamin E doping) to stabilize the free radicals and reduce the potential for oxidation. Wear resistance is improved with irradiation; however, there is minimal benefit with doses of greater than 10 Mrads.
REFERENCES: Collier JP, Currier BH, Kennedy FE, et al: Comparison of cross-linked polyethylene materials for orthopaedic applications. Clin Orthop Relat Res 2003;414:289-304.
Gordan AC, D’Lima DD, Colwell CW Jr: Highly cross-linked polyethylene in total hip arthroplasty. J Am Acad
Orthop Surg 2006;14:511-523.
Jacobs CA, Christian CP, Greenwald AS, et al: Clinical performance of highly cross-linked polyethylenes in total hip arthroplasty. J Bone Joint Surg Am 2007;89:2779-2786.

Question 38

Figure 16 shows the lateral radiograph of a patient who is scheduled to undergo an anterior cruciate ligament (ACL) reconstruction. If the graft is tensioned at 20° of flexion and the femoral tunnel is created by passing a reamer over the guide wire marked “A,” the resulting ligament reconstruction will excessively

Explanation

DISCUSSION: If the femoral tunnel is created using guide wire A, it will be too far anterior in the intercondylar notch. The distance between a central tibial insertion for the ACL and an anterior femoral tunnel will progressively increase as the knee is flexed. Therefore, if the graft is tensioned near extension, the ligament will excessively tighten as the knee flexes past 90°. This will result in restricted knee flexion or failure of the graft as full flexion is gained. There will be little effect on the ligament as it extends from 20° to 0° of flexion. If the graft is tensioned in significant flexion (greater than 60°), it will be excessively loose as the knee fully extends.
REFERENCES: Daniel DM, Fritschy D: Anterior cruciate ligament injuries, in DeLee JC, Drez D Jr (eds): Orthopaedic Sports Medicine: Principles and Practice. Philadelphia, PA, WB Saunders, 1994, pp 1313-1360.
Larson RL, Tailon M: Anterior cruciate ligament insufficiency: Principles of treatment. J Am Acad Orthop Surg 1994;2:26-35.

Question 39

Figure 3 is the clinical photograph of a 20-year-old college soccer player who has a 7-day history of worsening left ankle pain and swelling after being slide-tackled in a game. Radiograph findings of his ankle and foot are normal. He complains of malaise. His history includes a severe ankle sprain 3 months ago. The sprain caused him to miss half the season, but he was able to play in the last 2 games. What is the most appropriate treatment? Review Topic

Explanation

The clinical photograph shows a skin infection with an appearance consistent with methicillin-resistant Staphylococcus aureus. This infection should be clinically incised and allowed to drain and a course of antibiotics should follow. If this infection is not promptly treated with debridement, it likely will worsen and potentially spread to other teammates. Antibiotics are secondary to surgical debridement but are a necessary adjunct. Although this patient has a history of severe sprain, his malaise and skin appearance do not correlate with a ligament injury or fracture. Debridement in the training room is not appropriate and would likely not fully decompress the fluid collection.

Question 40

Which of the following prophylactic regimens for the prevention of deep venous thrombosis after knee arthroplasty has received a grade 1A recommendation in favor of its use from the American College of Chest Physicians (ACCP) in the 2004 guidelines?

Explanation

DISCUSSION: In the 2004 ACCP guidelines, there were three prophylactic regimens that received a grade 1A favorable recommendation. These included low-molecular-weight heparin, warfarin, or fondaparinux, as long as they are used for at least 10 days. If warfarin is used, the target INR should be 2.0 to 3.0, according to the guidelines. Pneumatic compression sleeves have gained popularity in the orthopaedic community but have not received a grade 1A rating from the ACCP at this time. Use of aspirin by itself is discouraged by the ACCP.
REFERENCE: Geerts WH, Pineo GF, Heit JA, et al: Prevention of venous thromboembolism: The seventh ACCP Conference on antithrombotic and thrombolytic therapy. Chest 2004;126:338S-400S.

Question 41

Figure 21 is the intraoperative fluoroscopic image of a 40-year-old man who felt a pop during a twisting injury to his right ankle. He underwent open reduction and internal fixation (ORIF) of a bimalleolar ankle fracture. During the surgery the medial and lateral malleoli fractures were reduced and rigidly was internally fixed. Following fracture fixation, which additional test is recommended to ensure mortise stability?

Explanation

DISCUSSION
Following ORIF of a known osseous injury, stress testing of the syndesmosis is recommended, especially for pronation-external rotation injuries. The Cotton test applies a laterally directed force to the fibula to assess for widening of the distal tibiofibular joint space. A positive Cotton test result indicates that syndesmotic stabilization is indicated. The Thompson test is used to determine Achilles tendon integrity. The squeeze test is a clinical, not intraoperative, assessment of syndesmotic injury. The anterior drawer test assesses the integrity of the anterior talofibular ligament.
RECOMMENDED READINGS
Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg. 2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882. View Abstract at PubMed
Pakarinen H, Flinkkilä T, Ohtonen P, Hyvönen P, Lakovaara M, Leppilahti J, Ristiniemi J. Intraoperative assessment of the stability of the distal tibiofibular joint in supination-external rotation injuries of the ankle: sensitivity, specificity, and reliability of two clinical tests. J Bone Joint Surg Am. 2011 Nov 16;93(22):2057-61. doi: 10.2106/JBJS.J.01287. PubMed PMID:

Question 42

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

DISCUSSION: 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.
REFERENCE: Deyo RA, Diehl AK, Rosenthal M: How many days of bed rest for acute low back pain? A randomized clinical trial. N Engl J Med 1986;315:1064-1070.

Question 43

-What is the most appropriate next treatment step?

Explanation

DISCUSSION FOR QUESTIONS 7 AND 8
Based on the patient’s signs and symptoms, the most likely diagnosis is osteomyelitis of the spine. The imaging studies do not reveal a herniated disk, which would be unusual in someone of this age. Aneurysmal bone cysts would involve the posterior elements with a more expansive lesion of bone, whereas this lesion involves primarily the body and anterior column. Hemangioma would likely not be present with systemic signs or symptoms and has a more characteristic coarse trabecular pattern on radiographs and scans. Given the likelihood that this patient has osteomyelitis of the spine, blood cultures may yield an organism about 50% of the time. If cultures are negative, an image-guided biopsy is warranted. A diagnosis needs to be established before treatment such as extension casting or bracing is rendered. Open biopsy may still be needed if needle biopsy is not diagnostic, but this is not the first treatment option. A chest CT scan is not appropriate as a first step when a tumor is presumed and a diagnosis has not been established.

Question 44

What percentage of bone weight is collagen?

Explanation

Bone is a composite of both inorganic and organic material. The inorganic component of bone comprises 60% to 70% of the tissue, water accounts for 5% to 8%, and the organic matrix makes up the remainder. Collagen accounts for 90% of the organic component and thus 20% to 25% of bone weight. Collagen accounts for the flexibility of bone. The inorganic component of bone is made primarily of calcium and phosphorous, in the analogue of hydroxyapatite, and other ions including sodium, magnesium, and carbonate.

Question 45

A 39-year-old man has had persistent right shoulder pain for the past 6 months. A formal physical therapy program has failed to provide relief, and an injection several months ago provided only short-term relief. Examination reveals a positive Neer and Hawkins test. There is no instability and the neurovascular examination is normal. Arthroscopy reveals a partial rotator cuff tear on the bursal side measuring 60% of the tendon thickness. What is the next most appropriate step in management?

Explanation

DISCUSSION: Although arthroscopic debridement with or without subacromial decompression is a reasonable response, the patient has positive impingement signs. Several recent studies regarding the surgical treatment of partial rotator cuff tears have demonstrated good to excellent results after repair of tears involving more than 50% of the tendon thickness. This was shown specifically for bursal-sided tears and joint-side tears. Biceps tenotomy is not indicated in a young patient.
REFERENCES: Matava MJ, Purcell DB, Rudzki JR: Partial-thickness rotator cuff tears.

Am J Sports Med 2005;33:1405-1417.
Fukuda H: The management of partial-thickness tears of the rotator cuff. J Bone Joint Surg Br 2003;85:3-11.

Question 46

A 72-year-old woman underwent a primary total hip arthroplasty 14 months ago. She states that the hip has now dislocated four times when rising from a low chair, requiring closed reduction. A radiograph is shown in Figure 3a and a CT scan of her pelvis is shown in Figure 3b. What is the most reliable method for rectifying her instability?

Explanation

DISCUSSION: The radiograph shows well-fixed components without evidence of loosening. The CT scan shows severe retroversion of the acetabular component. Revision of the component into the correct amount of anteversion
will most reliably rectify the instability in the face of severe component malposition.
REFERENCES: Parvizi J, Picinic E, Sharkey PF: Revision total hip arthroplasty for instability: Surgical techniques and principles. J Bone Joint Surg Am 2008;90:1134-1142.
DeWal H, Su E, DiCesare PE: Instability following total hip arthroplasty. Am J Orthop 2003;32:377-382. Barrack RL, Booth RE Jr, Lonner JH, et al (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 3.
Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 475-503.

Question 47

There is a risk of impaired forearm rotation after tension band fixation of an olecranon fracture with which of the following?

Explanation

DISCUSSION: Impaired pronation/supination can be seen if the K-wire is advanced either too radial or too far through the volar (anterior) cortex of the proximal ulna. The anterior interosseous nerve is also at risk with overpenetration. Conversely, migration and loosening of the K-wire is reduced with involvement of the anterior cortex.
The referenced study by Candal-Couto et al is a cadaveric study that found that K-wire insertion in less than 30 degrees in an ulnar direction led to impingement of the K-wire on the radial head/neck, biceps or supinator. They recommend placing these wires away from this danger zone in order to minimize rotation blocks.
The referenced study by Matthews et al is a case series of two patients who had limited forearm rotation after K-wire fixation. The etiology of limited rotation was found to be from direct overpenetration of the K-wire, which led to a mechanical block.

Question 48

What is the most common associated pathology in patients who have suprascapular nerve entrapment secondary to ganglion cysts?

Explanation

DISCUSSION: It is well known that suprascapular nerve entrapment can be secondary to many entities, and its association with ganglion cysts and SLAP lesions has been well documented. Because of a superior labral tear, synovial fluid will leak out of the joint underneath the labrum, causing the cyst and secondary compression of the nerve.
REFERENCES: Fehrman DA, Orwin JF, Jennings RM: Suprascapular nerve entrapment by ganglion cysts: A report of six cases with arthroscopic findings and review of the literature. Arthroscopy 1995;11:727-734.
Iannotti JP, Ramesey ML: Arthroscopic decompression of a ganglion cyst causing suprascapular nerve compression. Arthroscopy 1996;12:739-745.
Moore TP, Fritts HM, Quick DC, Buss DD: Suprascapular nerve entrapment caused by supraglenoid cyst compression. J Shoulder Elbow Surg 1997;6:455-462.

Question 49

A 36-year-old man was injured in a motorcycle collision and sustained the injury shown in Figure 70. He has a blood pressure (BP) of 70/40 mm Hg, pulse of 148 beats per minute (bpm), and Glasgow Coma Scale score of 6 (scores lower than 8 indicate severe brain injury), and there is negligible urine output. His airway is secure and intravenous (IV) access is obtained. Two liters of warm crystalloid solution are given; repeated vital signs reveal the same BP and a pulse of 142 bpm. What is the best next step?

Explanation

DISCUSSION
This patient has an anteroposterior compression pelvic fracture associated with shock. In patients with closed pelvic fractures and hypotension, mortality rises to approximately 1 in 4 (10%-42%) and hemorrhage is the major reversible contributing factor. Initial management of a major pelvic disruption associated with hemorrhage requires hemorrhage control and rapid fluid resuscitation. A pelvic binder should be placed to reduce pelvic volume. The patient has signs and symptoms of class IV hemorrhage, which include marked tachycardia exceeding 140, a significant decrease in BP, and a very narrow pulse pressure. Urinary output is negligible, and mental status is markedly depressed. The skin is cold and pale. The degree of exsanguination with class IV hemorrhage is immediately life threatening, and rapid transfusion and immediate surgical intervention are necessary. Nonresponse to fluid administration indicates persistent blood loss. Blood preparation should be emergency blood release. Type and cross-match of blood can be used for additional resuscitation in transient responders.
RECOMMENDED READINGS
Olson SA, Reilly MC, eds. Acetabular and Pelvic Fractures. Rosemont, IL: American Academy of Orthopaedic Surgeons; 2007:15-42.
Advanced Trauma Life Support for Doctors, ed 8. Chicago, IL, American College of Surgeons, 2008.
RESPONSES FOR QUESTIONS 71 THROUGH 74
- Retrograde intramedullary (IM) nailing
- Open reduction and internal fixation (ORIF) with screws alone
- Locking condylar plate
- Circular external fixation
- Lateral and medial plates
Which treatment option listed is best for each patient described?

71A

B
C

A 54-year-old healthy man with the condition seen in Figures 71a through 71d
- Retrograde intramedullary (IM) nailing
- Open reduction and internal fixation (ORIF) with screws alone
- Locking condylar plate
- Circular external fixation
- Lateral and medial plates

Question 50

When planning pin placement for external fixation of the tibia, what is the maximum extent of the knee capsular reflection from the subchondral joint line?

Explanation

Intracapsular pin placement is a concern for septic arthritis. Reid and associates and DeCoster and associates have demonstrated that the maximum distal extent of the knee capsule is 14 mm from the subchondral line and occurs in the posterolateral region. The recommended placement of external fixation pins is greater than 14 mm from the subchondral line of the proximal tibia.

Question 51

Figure 1 is the radiograph of a 31-year-old man who had left shoulder pain after a fall during a snowboarding jump. Residual displacement of 5 mm after closed reduction is most likely to result in

Explanation

Humerus fractures account for 11% of all fractures among snowboarders and are the second-most-common upper-extremity fracture after radius fractures (48%). Surgical fixation is recommended for fractures with residual displacement >5 mm, or >3 mm in active patients involved in frequent overhead activity. Malunion can result in a mechanical block to shoulder abduction or external rotation and altered rotator cuff mechanics, causing weakness. A rich arterial network provides a favorable healing environment for greater tuberosity fractures. Consequently, nonunion and osteonecrosis are uncommon.

Question 52

A 36-year-old professional baseball player reports the acute onset of severe right groin pain while attempting to avoid being hit by a baseball while at bat. Examination reveals tenderness, soft-tissue swelling, and ecchymosis in the right groin extending over the medial thigh. MRI scans are shown in Figures 8a and 8b. Management should consist of

Explanation

DISCUSSION: The MRI scans reveal a severe avulsion injury of the adductor muscle from the pubic ramus with muscle edema and hemorrhage. Injury to the adductor muscle group, a “pulled groin,” is caused by forceful external rotation of an abducted leg. Pain is immediate and severe in the groin region. Tenderness is at the site of injury along the subcutaneous border of the pubic ramus. Treatment is dictated by the severity of the symptoms but generally consists of rest, ice, and protected weight bearing, followed by a rehabilitation program that begins with gentle stretching and progresses to resistance exercise with a gradual return to sports. Immobilization should be avoided because this promotes muscle tightness and scarring. No data exist to suggest that open repair yields a better outcome than nonsurgical management. Tenotomy has been performed in high-level athletes with chronic groin pain following injury.
REFERENCES: Gilmore J: Groin pain in the soccer athlete: Fact, fiction, and treatment. Clin Sports Med 1998;17:787-793.
Irshad K, Feldman LS, Lavoie C, et al: Operative management of “hockey groin syndrome”:
12 years of experience in National Hockey League players. Surgery 2001;130:759-766.

Question 53

Which of the following factors has the most effect on the pullout strength of lumbar transpedicular screw fixation?

Explanation

DISCUSSION: Although all of the factors listed contribute to the pullout strength of transpedicular screw fixation, low bone density generally is felt to be the most influential.
REFERENCES: Wittenberg RH, Shea M, Swartz DE, Lee KS, White AA III, Hayes WC: Importance of bone mineral density in instrumented spine fusions. Spine 1991;16:647-652.
Zindrick MR, Wiltse LL, Widell EH, et al: A biomechanical study of intrapeduncular screw fixation in the lumbosacral spine. Clin Orthop 1986;203:99-112.

Question 54

Figures 23a and 23b show the radiographs of a 75-year-old woman who sustained an injury to her nondominant hand. Initial treatment should consist of

Explanation

DISCUSSION: Definitive treatment decisions for displaced distal radius fractures in the elderly are based on a number of factors related to the fracture pattern and patient demographics. The first step in any treatment algorithm is a closed reduction and splinting with reassessment of alignment parameters. This is an extra-articular fracture with dorsal angulation. Low-demand elderly patients can be treated well with accepted minor malreduction.
REFERENCES: Handoll HH, Madhok R: Conservative interventions for treating distal radial fractures in adults. Cochrane Database Syst Rev 2003;2:CD000314.
Young CF, Nanu AM, Checketts RG: Seven-year outcome following Colles’ type distal radial fracture: A comparison of two treatment methods. J Hand Surg Br 2003;28:422-426.

Question 55

Closed-chain exercise differs from open-chain exercise in which of the following ways?

Explanation

DISCUSSION: Closed-chain exercise requires the distal portion of the extremity to be fixed. It is more commonly used in lower extremity exercise, and movement is produced by co-contraction of muscles. Joint compression is increased, and multiple joints are involved with closed-chain exercise. In open-chain exercise, the distal portion of the extremity is free.
REFERENCES: Braddom RL (ed): Physical Medicine and Rehabilitation, ed 2. Philadelphia, PA, Saunders, 2000, pp 975-976.
Childs DC, Irrang JJ: The language of exercise and rehabilitation, in Delee JC, Drez D (eds): Orthopaedic Sports Medicine, ed 2. Philadelphia, PA, WB Saunders, 2003, vol 1, p 329.

Question 56

A 23-year-old otherwise healthy 6-ft, 4-in basketball player complains of pain in his knees. An examination reveals localized tenderness to palpation over the inferior pole of the patella. The patient notes a significant exacerbation of his pain when the examiner takes the knee from flexion to extension. Review Topic

Explanation

Patellar tendonitis is common in jumping sports such as basketball and volleyball. The pain is localized to the inferior border of the patella and is exacerbated by extension of the knee. Treatment for the vast majority of patients is nonsurgical and includes nonsteroidal anti-inflammatory drugs, physical therapy, and orthoses (patella tendon strap). Iliotibial band friction most commonly occurs in cyclists and runners (especially those who run up hills) and is a result of abrasion between the iliotibial band and the lateral femoral condyle. Localized tenderness with the knee flexed at 30 degrees is common. The Ober test may be helpful in making the diagnosis. Semimembranosis tendonitis most commonly occurs in male athletes during their fourth decade of life. The diagnosis is usually made with an MRI scan or nuclear imaging. Quadriceps tendonitis is similar to patellar tendonitis but is much less common. The pain may be associated with clicking and is localized to the superior border of the patella.

Question 57

What approach should be chosen for the injury seen in Figure 67? Review Topic

Explanation

(SBQ12TR.4) Which of the following statements about the lateral femoral cutaneous nerve is true?
Innervates the medial aspect of the proximal thigh
Originates from the dorsal roots of L4-L5
Course runs medial to the femoral artery
Courses along the medial border of the psoas muscle
Courses under the inguinal ligament PREFERRED RESPONSE 5

Question 58

In a patient who has undergone fusion with instrumentation from T4 to the sacrum for adult scoliosis, at which site is a pseudarthrosis most likely to be discovered?

Explanation

DISCUSSION: Although pseudarthrosis can be found anywhere within the spine that has been fused using long multisegmental fixation to the sacrum, it most commonly occurs at the lumbosacral junction. The thoracolumbar junction is another common site of potential pseudarthrosis. In this location, the anatomy changes from lumbar transverse processes to thoracic through the transition zone, and overlying instrumentation often makes it difficult to obtain enough sound bone on decorticated bone to achieve a successful fusion.
REFERENCES: Saer EH III, Winter RB, Lonstein JE: Long scoliosis fusion to the sacrum in adults with nonparalytic scoliosis: An improved method. Spine 1990;15;650-653.
Kostuik JP, Hall BB: Spinal fusions to the sacrum in adults with scoliosis. Spine

1983;8:489-500.
Balderston RA, Winter RB, Moe JH, et al: Fusion to the sacrum for nonparalytic scoliosis in the adult. Spine 1986;11:824-829.

Question 59

A 12-year-old girl who is Risser stage 3 has had intermittent mild midback pain for the past 4 weeks. The pain is worse after prolonged sitting and after carrying a heavy backpack at school. She occasionally takes acetaminophen, but the pain does not limit sport activities. Examination reveals a mild right rib prominence during forward bending. Neurologic examination is normal. Radiographs show a 20-degree right thoracic scoliosis with no congenital anomalies or lytic lesions. Management should consist of

Explanation

DISCUSSION: Mild scoliosis is not a painful condition, but it usually presents during adolescence. Intermittent back pain is reported by 25% to 30% of adolescents whether or not scoliosis is present. Such pain is often attributed to muscle strain from tight muscles, poor posture, or heavy school backpacks. The clinician must distinguish typical pain (mild, intermittent, nonlimiting) from atypical pain. The latter requires more careful examination and imaging studies (bone scan or MRI) to determine the source of pain. The patient’s age and right thoracic curve pattern are typical for idiopathic scoliosis; therefore, imaging of the neuroaxis is not necessary to look for cord syrinx, tethering, or tumor. Brace treatment is not required for this small curve unless future progression is demonstrated.
REFERENCES: Ramirez N, Johnston CE, Browne RH: The prevalence of back pain in children who have idiopathic scoliosis. J Bone Joint Surg Am 1997;79:364-368.
Hollingworth P: Back pain in children. Br J Rheum 1996;35:1022-1028.
Siambanes D, Martinez JW, Butler EW, et al: Influence of school backpacks on adolescent back pain. J Pediatr Orthop 2004;24:211-217.

Question 60

Figures 59a and 59b show the plain radiographs, and Figures 59c and 59d show the CT scan of a 77-year-old woman who has had pain in her back and both buttocks for the past 6 months. She reports that the pain radiates down her right thigh and leg when she is standing. What is the most likely diagnosis?

Explanation

DISCUSSION: Plain radiographs of this patient's Lumbar spine show degenerative changes. CT scan shows narrowing of the spinal canal and the patient's symptoms are consistent with lumbar stenosis. Measuring the AP diameter of the osseous canal, by CT, yields a correct diagnosis only 20% of the time. Whereas measurements of the cross sectional area of the dural sac by CT or of the AP diameter of the canal by myelography should lead to a correct diagnosis in 83% of patients.

Question 61

Which of the following actions increases radiation exposure to patients and personnel when using fluoroscopy?

Explanation

Continuous fluoroscopy and cineradiography exposes the patient and personnel to markedly increased levels of direct and scatter radiation exposure. Continuous fluoroscopy should be limited to only what is absolutely needed for safe completion of the procedure. By orienting the cathode ray tube beneath the patient and placing the image intensifier as close as clinically possible to the patient, scatter radiation exposure to the personnel is minimized.

Question 62

A 12-year-old boy who pitches on two “select” baseball teams has had pain in his dominant right shoulder for the past 6 weeks. The pain is present only with throwing and is associated with decreased throwing velocity and control. He has no radiation of pain or paraesthesias of the upper extremity. An AP radiograph and MRI scan are shown in Figures 19a and 19b, respectively. Management should consist of Review Topic

Explanation

The imaging study demonstrates characteristics of Little Leaguer’s shoulder, including physeal widening. This condition is secondary to overuse (typically throwing) and responds well to rest from the inciting activity. There is no evidence from the patient’s history or examination that he has an impingement syndrome, nor is there any indication of labral pathology on the MRI scan. The changes in the proximal humerus are classic for this condition and are not suggestive of a neoplastic process requiring biopsy for definitive diagnosis.

Question 63

A 3-year-old child has refused to walk for the past 2 days. Examination in the emergency department reveals a temperature of 102.2 degrees F (39 degrees C) and limited range of motion of the left hip. An AP pelvic radiograph is normal. Laboratory studies show a WBC count of 9,000/mm P 3 P , an erythrocyte sedimentation rate (ESR) of 65 mm/h, and a C-reactive protein level of 10.5 mg/L (normal < 0.4). What is the next most appropriate step in management?

Explanation

DISCUSSION: Examination reveals an irritable hip, creating a differential diagnosis of transient synovitis versus pyogenic hip arthritis. Kocher and associates described four criteria to help predict the presence of infection: inability to bear weight, fever, ESR of more than 40 mm/h, and a peripheral WBC count of more than 12,000/mmP³^P. This patient meets three of the four criteria, with a positive predictive value of 73% to 93% for joint infection. Therefore, aspiration of the hip is warranted, with a high likelihood that emergent hip arthrotomy will be indicated. Ideally, intravenous antibiotics should be administered after culture material has been obtained from needle aspiration of the hip. An urgent bone scan is better indicated as a screening test for sacroiliitis or diskitis. If the arthrocentesis proves negative, CT or MRI of the pelvis may be indicated to rule out a pelvic or psoas abscess.
REFERENCES: Del Beccaro MA, Champoux AN, Bockers T, et al: Septic arthritis versus transient synovitis of the hip: The value of screening laboratory tests. Ann Emerg Med 1992;21:1418-1422.
Kocher MS, Mandiga R, Zurakowski D, et al: Validation of a clinical prediction rule for the differentiation between septic arthritis and transient synovitis of the hip in children. J Bone Joint Surg Am 2004;86:1629-1635.
Kocher MS, Zurakowski D, Kasser JR: Differentiating between septic arthritis and transient synovitis of the hip in children: An evidence-based clinical prediction algorithm. J Bone Joint Surg Am 1999;81:1662-1670.

Question 64

Figure 7 shows the radiograph of an otherwise healthy 65-year-old man who injured his right dominant shoulder while skiing 18 months ago. He did not seek treatment at the time of the injury. He now reports intermittent soreness when playing golf but has no other limitations. Examination reveals full range of motion and no tenderness, but he has slight pain with a crossed arm adduction stress test. He is neurologically intact. Initial management should consist of

Explanation

DISCUSSION: The radiograph shows a displaced type II distal clavicle fracture with nonunion. Because the patient’s symptoms are minimal, the injury can be treated like a grade III acromioclavicular separation. Present management should consist of ice, anti-inflammatory drugs, activity modification, and perhaps physical therapy. If nonsurgical management fails to provide relief, the surgical options are varied with no uniformity in the literature regarding surgical treatment of this injury.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.
Craig EV: Fractures of the clavicle, in Rockwood CA Jr, Matsen FA III (eds): The Shoulder. Philadelphia, PA, WB Saunders, 1998, vol 1, pp 428-482.

Question 65

An obtunded 80-year-old man was found alone in his apartment after an apparent fall. A CT scan performed in the emergency department shows that he has an extensile injury of an ankylosed cervical spine. The fracture extends across the ossified C5-C6 disk space and into the lamina of C5. There is 1.5 cm of widening between the C5 and C6 vertebrae anteriorly. The patient's family asks you about the long-term impact of the fracture on his functional capacity and survival. You advise them that patients with fractures of the cervical spine with ankylosing conditions have

Explanation

DISCUSSION
Several studies have found that rates of neurologic deficit and mortality are higher for patients with ankylosing spondylitis and a spinal fracture than for age-matched controls. The 2011 work of Schoenfeld and associates, which directly compared patients with cervical fractures in ankylosed spines to age-and sex-matched controls who also had cervical fractures but no ankylosing condition, demonstrated that those with ankylosing spondylitis were at elevated risk for mortality for up to 2 years after sustaining a fracture. In a study by Westerveld and associates, the rate of neurologic deficit among patients with ankylosing spondylitis and a spinal fracture was 57.1% compared to 12.6% among controls.
RECOMMENDED READINGS
Westerveld LA, van Bemmel JC, Dhert WJ, Oner FC, Verlaan JJ. Clinical outcome after traumatic spinal fractures in patients with ankylosing spinal disorders compared with control patients. Spine J. 2014 May 1;14(5):729-40. doi: 10.1016/j.spinee.2013.06.038. Epub 2013 Aug 27. PubMed PMID: 23992936. View Abstract at PubMed
Schoenfeld AJ, Harris MB, McGuire KJ, Warholic N, Wood KB, Bono CM. Mortality in elderly patients with hyperostotic disease of the cervical spine after fracture: an age- and sex-matched study. Spine J. 2011 Apr;11(4):257-64. doi: 10.1016/j.spinee.2011.01.018. Epub 2011 Mar 5. PubMed PMID: 21377938. View Abstract at PubMed

Question 66

What cardiac condition causes most upper extremity emboli?

Explanation

EXPLANATION:
Atrial fibrillation is responsible for approximately 80% of all upper extremity emboli. All other cardiac conditions listed can cause upper extremity emboli; however, atrial fibrillation is the most common cause. Patients with an upper extremity embolic event should undergo prompt evaluation, with a careful history and physical examination as well as focused laboratory tests for hypercoagulability. Arterial Doppler studies or angiography is/are warranted. Electrocardiogram and echocardiogram are also used to evaluate for potential cardiac abnormalities. Consultation with vascular, radiology, and cardiology personnel is often necessary when patients present with upper extremity emboli. Treatment usually involves anticoagulation, embolectomy if necessary, and treatment for any recognized cardiac abnormality.

Question 67

Which of the following neurovascular structures is at greatest risk during the introduction of acetabular component fixation screws during total hip replacement?

Explanation

Wasielewski et al found on reviewing the literature that vascular injuries during acetabuIar screw placement are an uncommon yet devastating complication of total hip arthroplasty. Damage to the external iliac artery was the most frequent injury yet injury to the external iliac vein and the superior gluteal artery has also been reported Based upon their anatomic study and development of a quadrant
system they found that the posterior superior and posterior inferior quadrants of the acetabulum are the safest locations for screw placement because of better bone stock as well as less neurovascular structures as compared to the anterior quadrants.

Question 68

03 A 26-year-old woman has chronic toe pain after hitting a bedpost 3 months ago. A radiograph is shown in Figure 27. Her injury represents an avulsion of the

Explanation

The main function of the EDL is extension of the MTP joints of the lesser toes, so injury results in a claw toe deformity if left unrepaired. The EDL originates on the lateral tibial condyle, the anterior crest of the fibula, and the interosseous membrane and inserts on the base of the terminal phalanges of the four lesser toes. Innervated by the deep peroneal nerve, the EDL functions to extend the toes at the DIP joint and to dorsiflex and evert the foot. The EDL divides into two separate tendons beneath the superior retinaculum and then further divides into two lateral tendons to the fourth and fifth toes and two medial tendons to the second and third toes. The individual tendon of the EDL to each toe is joined on the lateral aspect by the tendon of the EDB. They are anchored at the level of the MTP joint by a fibroaponeurotic structure.
The EDB originates on the distal lateral and superior surface of the calcaneus and inserts on the
lateral aspect of the flexor digitorum longus tendon and also on to the base of the proximal phalanx of the first through fourth toes. There is no EDB tendon to the fifth toe. If an EDB laceration is easily identified at the time of an EDL repair, than it may be repaired as well, otherwise repair of the EDL alone is sufficient.
Heckman JD: Fractures and dislocation of the foot, in Rockwood CA Jr, Green DP, Bucholz RW, Heckman JD (eds):Rockwood and Green’s Fractures in Adults, ed 3. Philadelphia, PA, JB Lippincott, 1991, pp 2166-2169.
Coughlin MJ: Disorders of tendons, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 787-788.
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Question 69

Which of the following is considered the treatment of choice for a chondroblastoma of the proximal tibial epiphysis without intra-articular extension?

Explanation

DISCUSSION: Curettage and bone grafting typically is the preferred method of treatment for chondroblastoma, with local recurrence rates of approximately 10%. Some clinicians advocate the addition of adjuvants such as phenol. Left alone, these lesions can destroy bone and invade the joint. Large intra-articular lesions may require major joint reconstruction. Wide local excision rarely is required to eradicate the tumor. Radiation therapy rarely is indicated and only for unresectable or multiply recurrent lesions.
REFERENCES: Springfield DS, Capanna R, Gherlinzoni F, Picci P, Campanacci M: Chondroblastoma: A review of seventy cases. J Bone Joint Surg Am 1985;67:748-755.
Simon MA, Springfield DS, et al: Chondroblastoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 190.

Question 70

A 70-year-old female with a history of poorly controlled diabetes mellitus presents with purulent ulcers along the plantar aspect of her right forefoot and exposed metatarsal bone. She elects to undergo an amputation. She is insensate to the midfoot bilaterally. Her ankle-brachial index (ABI) for her right posterior tibial artery is 0.4. Further preoperative evaluation demonstrates a transcutaneous oxygen pressure of 45 and an albumin of 3.4. Which of the following would be a contraindication to performing a Syme amputation (ankle disarticulation) in this patient?

Explanation

DISCUSSION: A Syme amputation (ankle disarticulation) is a function-preserving amputation option that allows for terminal weight bearing, however strict criteria must be met for a patient to undergo successful Syme amputation. An ankle-brachial index (ABI) less than 0.5 for the posterior tibial artery in a patient with diabetes would be a contraindication for this procedure as success is dependent on the vascular supply of posterior tibial artery to the plantar flap and heel pad.
Pinzur et al retrospectively reviewed their results when performing a single-stage Syme ankle disarticulation in patients with diabetes either for peripheral neuropathy or infection. Patients with ABIs less than 0.5 for the posterior tibial artery had significantly decreased healing rates and smokers had a three-fold increased risk of postoperative infection.
Incorrect Answers:

Question 71

Figure 1 is the radiograph of a 21-year-old college lacrosse player who has a 2-year history of progressive left groin pain that is exacerbated by activity. Pain is preventing him from participating with his team. Examination reveals a fit man without tenderness to palpation around the hip. No clicking or popping occurs with hip range of motion. Strength of all muscles about the hip is normal, but there is some mild pain with resisted hip flexion and hip adduction. While lying supine, progressive hip flexion with internal rotation and adduction reproduces his groin pain.What is the most likely cause of this patient's pain?

Explanation

This clinical scenario describes a patient with FAI attributable to pincer (acetabular) deformity. This form of FAI, which involves prominence of the anterosuperior acetabular lip, may be more common among women. Decreased range of motion and pain occur secondary to the abutment of the femoral head against the acetabular labrum and rim. Hip flexion, combined with adduction and internal rotation, recreates this contact and causes pain, but CAM or pincer etiology remains unknown. The differential diagnosis of hip pain in a young athlete includes femoral neck stress reaction/fracture, sacroiliac arthritis, intra-articular loose body, trochanteric bursitis, osteitis pubis, and hernia. No information presented in this scenario suggests any of these causes. Diagnosis of FAI is best performed via MR imaging, with an arthrogram increasing the sensitivity and specificity for labral pathology. Ultrasonography may be useful in the diagnosis of dysplasia or for dynamic assessment of a snapping hip, but ultrasonography is not commonly used to diagnose labral pathology. Although concomitant chondral lesions of the femoral head are uncommon, the forced leverage of the anterosuperior femoral neck upon the anterior acetabulum may result in a “contra-coup” chondral injury on the posteroinferior acetabulum. This is the most common location of chondral lesions in this scenario. Without bony resection to prevent further impingement, this patient will continue to experience symptoms. Because there is no evidence of femoral neck prominence (CAM lesion), there is no indication for osteoplasty of the femoral neck; resection of the pincer lesion is necessary. This will often require take-down of the labrum in this location. If possible, iatrogenic or traumatic labral tears should subsequently be repaired after pincer debridement because the labrum has important functions for hip stability and maintenance of the suction seal of the joint.

Question 72

In a diagnostic test, the proportion of individuals who are truly free of a designated disorder identified by the test is known as

Explanation

Specificity refers to the proportion of individuals who are truly free of the designated disorder who are so identified by the test. Sensitivity refers to the proportion of individuals who truly have the disorder who are so identified by the test. Positive predictive value refers to the proportion of individuals with a positive test who have the disorder. Negative predictive value refers to the proportion of individuals with a negative test who are free of the disorder. Accuracy is the overall ability to identify patients with the disorder (true positives) and without the disorder (true negatives) in the study population.

Question 73

A neurologic injury at T11-L2 with loss of bowel and bladder control is best described as what syndrome?

Explanation

DISCUSSION: Conus medullaris syndrome describes isolated loss of bowel and bladder function, usually at T12-L1 but can include T11-L2. In central cord syndrome, lower extremity motor function is better than upper extremity function. Cauda equina syndrome generally involves injury at the lumbar levels, with some degree of lower extremity motor loss. Posterior cord syndrome is characterized by preservation of motor function below the level of injury and position/vibratory sensory loss. In anterior cord syndrome, the lower extremity findings include loss of light touch, sharp/dull, and temperature sensations below the level of injury, as well as motor function.
REFERENCES: Apple DF Jr: Spinal cord injury rehabilitation, in Rothman RH, Simeone FA (eds): The Spine, ed 3. Philadelphia, PA, WB Saunders, 1992, Chapter 31.
Weisberg LA: Neurologic localization: Lesions below foramen magnum, in Weisberg LA, Strub RL, Garcia CA (eds): Adult Neurology, ed 2. St. Louis, MO, Mosby, 1993.

Question 74

A 35-year-old skiier presents with pain in the left buttock and proximal posterior thigh after a fall. His clinical appearance is shown in Figure A. He is enrolled in 8 weeks of physical therapy after 2 weeks of rest, icing and NSAIDS. He returns for follow-up 6 months after his injury and has persistent ischial tuberosity pain with running. Examination confirms focal ischial tuberosity tenderness. MRI images are seen in Figures B and C. Which surgical option is most appropriate? Review Topic

Explanation

This patient has a partial hamstring avulsion injury. If symptoms persist after a period of therapy and rest, operative repair to the ischial tuberosity is indicated.
Untreated partial hamstring ruptures may present with residual pain, weakness and hamstring dysfunction. The mechanism is eccentric lengthening (sprinting or cutting) A proposed treatment algorithm is: (1) Nonoperative management for single tendon avulsion with <2cm retraction. The ruptured tendon scars to intact tendons. (2) Repair for acute 3-tendon rupture (semitendinosus, semimembranosus, biceps femoris) with retraction >= 2cm. (3) Surgery for young (<50y) patients with 2 tendon avulsion and retraction >= 2cm.
Bowman et al. examined the outcomes of operative management of partial hamstring tears in 17 patients. They found no postoperative difficulties with ADLs, and no recurrent surgery was required. All patients returned to their preoperative level of activity. They concluded that surgery can lead to good function with low complications and is reserved for patients who have failed nonoperative management.
Hofmann et al. retrospectively reviewed 19 patients with nonoperatively managed complete hamstring avulsions. They found diminished SF-12 scores, diminished hamstring strength at 45° and 90° of flexion (62% and 66%, respectively) compared with the normal side. They concluded that nonsurgical management leads to both subjective functional and objective strength deficits.
Figure A shows pronounced bruising from hematoma tracking following the injury. Figures B and C are coronal and axial images showing partial avulsion of the right hamstring insertion. The images correspond with Illustration B, with arrows pointing to the "sickle sign" . Illustration A shows the origins of the hamstring tendons. Illustration C shows the origins of the hamstring group (bf, biceps femoris; st, semitendinosus; sm, semimembranosus; qf, quadratus femoris; am, adductor magnus)
Incorrect Answers:

Question 75

below demonstrate the radiographs obtained from a year-old woman with end-stage debilitating osteoarthritis of the right hip. She is contemplating total hip arthroplasty (THA). She has a history of right hip dysplasia and underwent hip osteotomy as an adolescent. Over the years, nonsurgical treatment, including weight loss, activity modifications, and intra-articular injections, has failed. Her infection work-up reveals laboratory findings within defined limits. A further work-up reveals elevations in serum cobalt and chromium levels and fluid collections surrounding the hip on MRI with MARS. Revision THA is recommended. The most common complication following revision of a failed metal-on- metal hip arthroplasty is

Explanation

THA has proven durable and reliable for pain relief and improving function for patients with end-stage arthritis. Appropriate bearing selection is critical to minimize wear and hip complications. A metal-on- metal articulation is associated with excellent wear rates in vitro. With its capacity to offer a low wear rate with large femoral heads, it is an attractive bearing choice for THA. However, local soft-tissue reactions, pseudotumors, and potential systemic reactions including renal failure, cardiomyopathy, carcinogenesis, and potential teratogenesis with potential transfer of metal ions across the placental barrier make metal-on-metal bearings less desirable and relatively contraindicated for younger women of child- bearing age. The workup of a painful metal-on-metal hip arthroplasty necessitates a systematic approach. Several algorithms have been proposed. Routine laboratory studies including sedimentation rate, CRP, and serum cobalt and chromium ion levels should be obtained for all patients with pain. Advanced imaging including MARS MRI should be performed to evaluate for the presence of fluid collections, pseudotumors, and abductor mechanism destruction. Infection can coexist with metal-on-metal reactions, so, when indicated (if the CRP level is elevated), a hip arthrocentesis should be obtained. However, in this setting, a manual cell count and differential should be obtained because an automated cell counter may provide falsely elevated cellcounts. The results of revision surgery for a failed metal-on-metal hip prosthesis can be variable. The amount of local tissue destruction and the integrity of the hip abductor mechanism can greatly influence outcomes. Instability is the most common complication following revision of failed metal-on-metal hip replacements.

Question 76

A 54-year-old man undergoes uneventful anterior cervical diskectomy and interbody fusion at C4-5 for focal disk herniation and C5 radiculopathy. At the 3-week follow-up examination, the patient reports a persistent cough. Pulmonary evaluation reveals a mild but persistent aspiration. Laryngoscopy reveals partial paralysis of the left vocal cord, most likely caused by

Explanation

DISCUSSION: The exact anatomic event responsible for vocal cord paralysis associated with anterior cervical surgery remains a question. Apfelbaum and associates, in an excellent review of 900 anterior cervical surgeries, identified 30 patients with vocal cord paralysis, 3 of which were permanent. They showed that retractors placed under the longus coli for anterior cervical exposures can compress the laryngeal-tracheal branches within the larynx against the tented endotracheal tube rather than the recurrent laryngeal nerve, which is extrinsic to the larynx. By releasing the endotracheal cuff and allowing the tube to recenter itself after placement of the retractors, they were able to decrease vocal cord injury from 6.4% to 1.7%. Jewett and associates suggested that a left-sided approach may result in a lower incidence of injury. Endotracheal intubation is the second most common cause of vocal cord injury, with an incidence of approximately 2%.
REFERENCES: Apfelbaum RI, Kriskovich MD, Haller JR: On the incidence, cause, and prevention of recurrent laryngeal nerve paralysis during anterior cervical spine surgery. Spine 2000;25:2906-2912.
Jewett BA, Menico GA, Spengler DM, Coleman SC, Netterville JL: Vocal Cord Paralysis Following Anterior Cervical Spine Surgery. Paper presented at the annual meeting or the Cervical Spine Research Society, December 2000, Charleston SC, Paper #7.

Question 77

Figures 82a through 82c show the radiograph and 3-dimensional (3-D) CT scans of a 2-year-old boy whose scoliosis has progressed 15 degrees during the past year. The child is clinically healthy. He has been walking since 11 months of age. An MRI scan of the entire spine revealed no other anomalies. What additional study is indicated? Review Topic

Explanation

Renal anomalies are found in as many as one-third of patients with congenital scoliosis, so a renal ultrasound should be obtained. There may be other anomalies, including cardiac. There are no other anomalies on MRI, so flexion-extension cervical spine radiographs are not indicated. There is no associated marrow or platelet problem with hemivertebra. There is no indication for blood cultures because this is a noninfection disorder. The radiographs and 3-D CT scans show a hemivertebra scoliosis already beyond 45 degrees. Resection of the hemivertebra with stabilization is the indicated treatment. The scoliosis will get worse with observation and bracing. Fusion posteriorly can only minimally correct and not stop progression of the scoliosis.

Question 78

Which examination finding points toward a brachial plexus injury rather than root avulsion?

Explanation

EXPLANATION:
A brachial plexus injury distal to the root level should leave the rhomboid muscle with intact function. Root avulsions of C5-6 will cause weakness of the rhomboids. The branching of the dorsal scapular nerve is proximal and often spared with upper brachial plexus injuries. Winging and biceps weakness may occur
with either injury, and an ipsilateral fracture does not differentiate an avulsion from a brachial plexus injury.

Question 79

During treatment of rupture of the subscapularis tendon with associated biceps instability, treatment of the biceps tendon should include which of the following?

Explanation

DISCUSSION: With subscapularis tendon ruptures that have biceps tendon pathology, treatment with tenodesis or tenotomy has improved clinical results. Subluxation or dislocation of the biceps tendon is common with subscapularis rupture. Dislocation of the biceps can occur either beneath the tendon, within the tendon, or extra-articularly. In all cases, the restraints to medial translations of the biceps have been disrupted. Attempts at recentering the biceps have not been successful, and clinical results appear to be improved when tenodesis or tenotomy is employed in the treatment of the unstable biceps associated with subscapularis tears.
REFERENCES: Edwards TB, Walch G, Sirvenaux F, et al: Repair of tears of the subscapularis: Surgical technique. J Bone Joint Surg Am 2006;88:1-10.
Deutsch A, Altchek DW, Veltri DM, et al: Traumatic tears of the subscapularis tendon: Clinical diagnosis, magnetic resonance imaging findings, and operative treatment. Am J Sports Med 1997;25:13-22.
Edwards TB, Walch G, Sirveaux F, et al: Repair of tears of the subscapularis. J Bone Joint Surg Am 2005;87:725-730.

Question 80

A 45-year-old man who is a smoker has a significant hemothorax and bilateral closed femoral fractures. On insertion of a chest tube, 1,100 mL of blood was returned. He has had 75 mL of chest tube output over the last 2 hours while being resuscitated in the ICU. His base deficit is now 2 and his urine output has been 3 mL/kg over the last hour. What is the next most appropriate step in management?

Explanation

DISCUSSION: Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm.
REFERENCES: Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.
Pape HC, Zelle BA, Hildebrand F, et al: Reamed femoral nailing in sheep: Does irrigation and aspiration of intramedullary contents alter the systemic response? J Bone Joint Surg Am 2005;87:2515-2522.

Question 81

This image represents the end stage of an uncompensated rotator cuff tear.

Explanation

DISCUSSION
Axillary lateral and anteroposterior (AP) images of the right shoulder (Figures 59c and 59d) reveal osteoarthrosis of the glenohumeral joint, which typically is not associated with significant rotator cuff pathology. An examination often shows limitations in range of motion, crepitance, and pain with motion. An AP radiographic image of the right shoulder (Figure 59b) reveals proximal humeral migration, which normally correlates with rotator cuff tear size. Tears extending into the infraspinatus tendon are associated with more humeral migration than is seen with isolated supraspinatus tears. Presenting complaints are usually of pain and weakness. Examination findings include subacromial crepitance and weakness during rotator cuff testing. Rarely, this may be associated with pseudoparalysis in large uncompensated rotator cuff tears. The CT image of the right shoulder (Figure 59a) shows superior migration of the humerus with respect to the glenoid surface and end-stage
degenerative changes at the glenohumeral joint. These changes are classified as rotator cuff arthropathy. Pain and weakness are common, as is the presence of pseudoparalysis and limited range of motion.
RECOMMENDED READINGS
Kelly JD Jr, Norris TR. Decision making in glenohumeral arthroplasty. J Arthroplasty. 2003 Jan;18(1):75-82. Review. PubMed PMID: 12555187. View Abstract at PubMed
Keener JD, Wei AS, Kim HM, Steger-May K, Yamaguchi K. Proximal humeral migration in shoulders with symptomatic and asymptomatic rotator cuff tears. J Bone Joint Surg Am. 2009 Jun;91(6):1405-13. doi: 10.2106/JBJS.H.00854. PubMed PMID:

Question 82

A coach of three football teams—the B team, junior varsity team, and varsity team—wants to study the average times in the 40-yard dash for his players. Which test would help him determine if the mean 40-yard dash times for the athletes on one team are different from those on the other teams?

Explanation

Data collected in research studies fall into one of two categories—continuous or discrete. Continuous data can be displayed on a curve. Examples include height, weight, and time recorded in a 40-yard dash. Discrete data represent data that fall into specific categories such as gender or the presence or absence of a risk factor. ANOVA is used to determine statistical significance in mean values of continuous data when there are more than two independent samples. The 2-sample t test compares mean values of continuous data between two independent groups. The Chi-square test and Fisher's exact tests are tests used to analyze discrete data.

Question 83

An 11-year-old child has Ewing’s sarcoma of the femoral diaphysis with a small soft-tissue mass. Staging studies show no evidence of metastases. Treatment should consist of

Explanation

DISCUSSION: The use of chemotherapy has dramatically improved survival rates of patients with Ewing’s sarcoma. Local disease is best handled with wide resection to decrease local recurrence and to avoid the complications of radiation therapy (ie, secondary sarcomas). Radiation therapy alone is reserved for unresectable lesions or poor surgical margins. Amputation generally is not necessary.
REFERENCES: Toni A, Neff JR, Sudanese A, et al: The role of surgical therapy in patients with non-metastatic Ewing’s sarcoma of the limbs. Clin Orthop 1991;286:225.
Picci P, Rougraff BT, Bacci G, et al: Prognostic significance of histopathologic response to chemotherapy in non-metastatic Ewing’s sarcoma of the extremities. J Clin Oncol 1993;11:1763.
Gibbs CP Jr, Weber K, Scarborough MT: Malignant Bone Tumors. Instr Course Lect 2002;51:413-428.
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Question 84

A 3-year-old girl developed torticollis eight months ago after a severe respiratory tract infection. A initial trial of halter traction was attempted without success. A trial of halo traction was then performed for 3 weeks and then a dynamic computed tomographic (CT) was obtained and shown in Figure A. Panel (a) shows an axial image with maximal rotation to the left. Panel (b) shows an axial image with maximal rotation to the right. What is the most appropriate next step in management? Review Topic

Explanation

Lumbar epidural injection
Physical therapy with core strengthening and anti-inflammatory medications as needed
Lumbar decompression
Lumbar decompression and fusion
MRI of the cervical and thoracic spine
The clinical scenario is consistent with a patient with symptoms of degenerative spondylolisthesis AND symptoms of myelopathy. Myelopathy must be ruled out by performing an MRI of the cervical and thoracic spine.
Tandem stenosis occurs in approximately 5 to 25% of patients. Because of the stepwise progressive nature of myelopathy, treatment of myelopathy often takes precedence over lumbar spinal stenosis.
Rhee et al. found that the sensitivity and specificity of specific physical exam findings varies. Both the upward babinski reflex and the presence of clonus were found to be very non-sensitive (13%). The most sensitive provacative test was found to be the Hoffman sign (59%).
Salvi et al. reviewed the classic presentations for cervical myelopathy including demographics, history, and physical exam findings (the inability to preform a tandem gait, hyperreflexia, an abnormal babinksi and hoffman reflex, the inability to preform rapid movements and bilateral muscle weakness). Additionally they identify other potential causes for myelopathy, including multiple sclerosis, amyotrophic lateral sclerosis, multifocal motor neuropathy, and Guillain-Barre´syndrome.
Maezawa et al. showed that gait analysis can identify a pattern in patients with myelopathy. Patients with severe myelopathy have a characteristic gait with hyperextension of the knee in the stance phase without plantar flexion of the ankle in the swing phase. They also have decreased walking speed and stride length with a prolonged stance phase.
Figure A and B show a classic degenerative spondylolisthesis.
Incorrect Answers:

Question 85

A 45-year-old man is seeking evaluation of an injury sustained in a motor vehicle accident 10 weeks ago. Current radiographs are shown in Figures 2a and 2b. Based on the radiographic findings, what is the most likely diagnosis?

Explanation

DISCUSSION: An increased density of the talar body compared to the distal tibia following fracture of the talar neck is highly suggestive of vascular compromise of the talar body. Subchondral osteopenia of the talus at 6 to 8 weeks (Hawkins sign) is a favorable sign but does not eliminate the possibility of osteonecrosis.
REFERENCES: Elgafy H, Ebraheim NA, Tile M, Stephen D, Kase J: Fractures of the talus: Experience of two level 1 trauma centers. Foot Ankle Int 2000;21:1023-1029.
Berlet GC, Lee TH, Massa EG: Talar neck fractures. Orthop Clin North Am 2001;32:53-64.

Question 86

A newborn girl with an isolated unilateral dislocatable hip is placed in a Pavlik harness with the hips flexed 100 degrees and at resting abduction. Figure 23 shows an ultrasound obtained 2 weeks later. What is the next step in management?

Explanation

DISCUSSION: The infant has a well-positioned hip in the Pavlik harness and treatment should be continued in the current position. The success rate is over 90% with the use of this device for a dislocatable hip. Ultrasound is a useful tool to confirm appropriate positioning of the cartilaginous femoral head during treatment. If the femoral head is not reduced after 2 to

3 weeks in the harness, this mode of treatment should be abandoned. Forceful extreme abduction can cause osteonecrosis of the femoral epiphysis and should be avoided. Closed reduction, arthrography, and spica casting are indicated if the hip cannot be maintained in a reduced position with the harness.
REFERENCES: Lehmann HP, Hinton R, Morello P, et al: Developmental dysplasia of the hip practice guideline: Technical report. Committee on Quality Improvement, and Subcommittee on Developmental Dysplasia of the Hip. Pediatrics 2000;105:E57.
Haynes RJ: Developmental dysplasia of the hip: Etiology, pathogenesis, and examination and physical findings in the newborn. Instr Course Lect 2001;50:535-540.

Question 87

The teardrop shape marked with an asterisk in Figure 61 represents what anatomic structure?

Explanation

DISCUSSION: The teardrop can be visualized on the obturator outlet view of the pelvis and represents a thick column of bone that runs from the AIIS to the PSIS. Half pins for eternal fixation frames or screws can be inserted into this column for fixation of fractures.
REFERENCES: Gardner MJ, Nork SE: Stabilization of unstable pelvic fractures with supra-acetabular compression external fixation. J Orthop Trauma 2007;21:269-273.
Haidukewych GJ, Kumar S, Prpa B: Placement of half-pins for supra-acetabular external fixation: An anatomic study. Clin Orthop Relat Res 2003;411:269-273.
Kim WY, Hearn TC, Seleem O, et al: Effect of pin location on stability of pelvic external fixation. Clin Orthop Relat Res 1999;361:237-244.

Question 88

A 32-year-old woman has had progressive left foot pain over the first metatarsophalangeal (MTP) joint. Footwear is becoming problematic. There is full range of motion of the first MTP with medial eminence pain. Her weightbearing radiograph reveals a hallux valgus angle (HVA) of 35 degrees and a 1-2 intermetatarsal angle (IMA) of 10 degrees. What is the best next step?

Explanation

DISCUSSION
Patients with painful progressive hallux valgus are surgical candidates. Presurgical evaluation includes radiographic examination. The IMA between the first and second metatarsals as well as the HVA must be measured. If the IMA is smaller than 15 degrees and the HVA is smaller than 35 degrees, a distal osteotomy is preferred. Distal soft-tissue reconstruction is only useful for IMAs smaller than 11 degrees and HVAs smaller than 25 degrees. Proximal osteotomies and the Lapidus bunionectomy are reserved for larger hallux valgus deformities with IMAs exceeding 15 degrees and HVAs exceeding 35 degrees.
RECOMMENDED READINGS
Pentikainen I, Ojala R, Ohtonen P, Piippo J, Leppilahti J. Distal Chevron Osteotomy: Preoperative Radiological Factors Contributing to Long-Term Radiological Recurrence of Hallux
Valgus. Foot Ankle Int. 2014 Sep 5. pii: 1071100714548703. [Epub ahead of print] PubMed PMID: 25192724. View Abstract at PubMed
Fakoor M, Sarafan N, Mohammadhoseini P, Khorami M, Arti H, Mosavi S, Aghaeeaghdam A. Comparison of Clinical Outcomes of Scarf and Chevron Osteotomies and the McBride Procedure in the Treatment of Hallux Valgus Deformity. Arch Bone Jt Surg. 2014 Mar;2(1):31-

Question 89

An 18-year-old male football player dislocated his elbow during a game. A post-reduction MRI scan is shown in Figure 1. The injury is initially treated non-operatively, but the patient continues to note subjective instability and pain when attempting to push up from a chair. Surgical intervention is planned for repair/reconstruction. What guidance should be provided to the patient and therapist in the early postoperative period?

Explanation

When performing reverse shoulder arthroplasty, what factor leads to an increase in the complication indicated by the black arrow in Figure 1?

Question 90

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

DISCUSSION: 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.
REFERENCES: 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.
Siris ES: Paget’s disease of bone, in Favus MJ (ed): Primer on the Metabolic Bone Diseases and Disorders of Mineral Metabolism. New York, NY, Raven Press, 1993, pp 375-384.

Question 91

-What is the most appropriate initial treatment for her condition?

Explanation

DISCUSSION FOR QUESTIONS 73 THROUGH 75
This patient has a history most consistent with multidirectional instability. A lax capsule causes subluxation of the shoulder and strain on the rotator cuff and may result in pain and instability. The capsule is most closely associated with the cause of her problem. Initial treatment for multidirectional instability is physical therapy focusing on restoring balance to the shoulder with rotator cuff and scapular stabilization exercises. Nonsurgical therapy should be protracted and is the mainstay of treatment in this scenario. This patient has exhausted all nonsurgical measures and is now a candidate for surgical reconstruction. Capsular plication will best address the lax capsule and provide the best option for reducing her symptoms. The rotator cuff and biceps tendon may be secondarily strained but are not the primary sources of the problem. The brachial plexus does not address the etiology, but rather the symptoms that may occur as a result of instability of the shoulder joint.
Complete rest will not alleviate the patient's underlying condition because the shoulder girdle may still be weak and symptoms likely will return. A corticosteroid injection and arthroscopic surgery are too invasive as initial treatment for this condition. Arthroscopic rotator cuff repair, a biceps tenodesis, and superior labral anterior-posterior repair are unlikely to result in symptomatic improvement for this patient and are not associated with pathologic findings in the setting of multidirectional instability.

Question 92

A 25-year-old patient presents with a posterior wall/ posterior column acetabular fracture. She is scheduled for open reduction internal fixation through a posterior approach. What position of the leg exerts the least amount of intraneural pressure on the sciatic nerve?

Explanation

DISCUSSION: In the cited study, researchers measured tissue fluid pressure within the sciatic nerve in cadaveric specimens using a pressure transducer. The hip and knee were taken through a combination of ranges and found that the clinically relevant increase in pressure happened with the hip flexed at 90 degrees and the knee fully extended. They concluded that increased intraneural pressure was related to excursion of the nerve as linear distance between the greater sciatic notch and the distal leg increase. Hence, according to the question stem, to avoid traction injury, the reverse position should be implemented (hip extension and knee flexion).

Question 93

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Explanation

Surgical indications for reverse total shoulder arthroplasty are expanding. In the setting of rotator cuff tear arthroplasty in which the native humeral head migrates superiorly, these implants impart several kinematic advantages. Implant center of rotation medial to the former joint surface improves glenoid component stability as the resultant force vector passes through the component throughout the arc of motion. A stable and fixed fulcrum for elevation is provided by matched radius of curvature between the glenoid and humeral components. A more distal center of rotation increases resting length and tone of the deltoid muscle, improving its effectiveness as a shoulder elevator. Medialized joint center of rotation increases the moment arm of the deltoid, requiring less muscle force to produce a given torque. This results in decreased articular shear stress.

Question 94

9A 9B 9C 9D Figures 9a through 9d are the radiographs of a 21-year-old woman who is involved in a high-speed motor vehicle collision and sustains an isolated right closed-foot injury. Before surgery, the patient is advised about the relatively poor long-term outcomes associated with this injury. What is the most common reason for functional limitations after surgical treatment in this scenario?

Explanation

DISCUSSION
When a displaced talar neck fracture occurs, the rate of osteonecrosis is high; however, many revascularize the talus without collapse. A nonunion can occur but is less common than osteonecrosis and arthritis. A varus malunion can be debilitating and lead to subtalar arthritis. In a fracture with the talar body dislocated posteromedially (such as in this example) neurologic deficits in the tibial nerve distribution are common but typically improve with urgent
reduction. Studies show that posttraumatic subtalar arthritis is common after this injury and is the most likely cause of long-term functional impairment.
RECOMMENDED READINGS
Vallier HA, Nork SE, Barei DP, Benirschke SK, Sangeorzan BJ. Talar neck fractures: results and outcomes. J Bone Joint Surg Am. 2004 Aug;86-A(8):1616-24. PubMed PMID: 15292407. View Abstract at PubMed
Lindvall E, Haidukewych G, DiPasquale T, Herscovici D Jr, Sanders R. Open reduction and stable fixation of isolated, displaced talar neck and body fractures. J Bone Joint Surg Am. 2004 Oct;86-A(10):2229-34. PubMed PMID: 15466732. View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 10 THROUGH 12

10A

10B

10C
Figure 10a is the radiograph of a 30-year-old man who sustained an injury in a motor vehicle collision.

Question 95

Figures 1a and 1b show the sagittal T 2 - and T 1 -weighted MRI scans of a 25-year-old intravenous drug abuser who has low back pain that is increasing in intensity. Laboratory studies show a WBC count of 10,000/mm 3 and an erythrocyte sedimentation rate of 80 mm/h. Blood culture is negative. Initial management consist of

Explanation

DISCUSSION: The MRI scans show vertebral diskitis/osteomyelitis. The treatment of spinal infection in adults should be organism specific; therefore, initial management should consist of CT-guided closed biopsy prior to administration of antibiotic coverage. An open biopsy is indicated for a failed closed biopsy or failure of nonsurgical management. Although Staphylococcus aureus is the most common bacteria, a history of intravenous drug abuse raises suspicion for other organisms, including Pseudomonas.
REFERENCES: Tay BK, Deckey J, Hu SS: Spinal Infections. J Am Acad Orthop Surg 2002;10:188-197.
Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 431-439.

Question 96

Figures 18a through 18c show the clinical photograph, radiograph, and CT scan of a 21-year-old man who reports persistent pain after injuring his right shoulder 4 months ago. What is the most likely factor associated with this patient’s diagnosis?

Explanation

The more severe the trauma, the higher the rate of subsequent clavicular nonunion. Neither duration nor type of immobilization has been clearly demonstrated to be a causative factor in the development of nonunion. Similarly, closed reduction has not been found to alter the healing course in midshaft clavicular fractures.

Question 97

An 18-month-old infant with myelomeningocele and rigid clubfeet has grade 5 quadriceps and hamstring strength, but no muscles are functioning below the knee. What is the best treatment option for the rigid clubfeet?

Explanation

DISCUSSION: This child has the potential to walk and therefore should have all the contracted structures in the feet released as necessary to place the feet in a plantigrade position for fitting of ankle-foot orthoses. Physical therapy, manipulation, and casting may provide some benefit in a newborn with flexible feet but are not effective in an older infant with rigid clubfeet. Botulinum injections and tendon transfers are of no use because there are no muscles functioning below the knee. Tendon releases are more effective than tendon transfers in children with myelomeningocele.
REFERENCES: Mazur JM: Management of foot and ankle deformities in the ambulatory child with myelomeningocele, in Sarwark JR, Lubicky JP (eds): Caring for the Child with Spina Bifida. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2001, pp 155-160.
Dias LS: Surgical management of acquired foot and ankle deformities, in Sarwark JR, Lubicky JP (eds): Caring for the Child with Spina Bifida. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2001, pp 161-170.

Question 98

When performing a Green transfer for cerebral palsy—flexor carpi ulnaris (FCU) to extensor carpi radialis brevis (ECRB)—in addition to improving wrist extension, what other motion may be improved if the FCU is routed around the ulna instead of through the interosseous membrane?

Explanation

EXPLANATION:
The typical upper extremity deformity in spastic hemiplegic cerebral palsy consists of shoulder internal rotation, elbow flexion, forearm pronation and wrist flexion, and ulnar deviation. The pronation position of the forearm can make bimanual activities more challenging for the child. The wrist flexion and ulnar deviation deformity interferes with finger function and therefore with grasp and release patterns. By transferring the FCU tendon to the ECRB, the deforming force is released, and central wrist extension is augmented. This transfer can lead to a supination moment when it is routed around the ulna to the ECRB insertion on the dorsum of the wrist. Thumb and finger extension are not affected by an FCU-to-ECRB tendon transfer. Forearm supination, not pronation, is potentially improved with this tendon transfer.

Question 99

A 10-year-old boy with severe hemophilia A (factor VIII) sustained an injury to his right forearm 2 hours ago when a classmate fell on his arm during a scuffle. Examination reveals moderate swelling in the forearm, decreased sensation in the distribution of the median and ulnar nerves, and pain on passive extension of the fingers. What is the most appropriate sequence of treatment?

Explanation

DISCUSSION: The patient has severe hemophilia with a volar forearm hemorrhage and an emerging compartment syndrome. Therefore, it is critical to normalize the clotting deficiency as the first step in treatment. In a patient who has a factor VIII level of less than 1% and no inhibitors to factor VIII, transfusion with 4 unit/kg will typically raise the factor VIII level to 100%. Continuous transfusion can then be used to maintain this level. Compartment pressures can be safely measured after infusion of factor VIII. Because the hemorrhage is of limited duration and any surgery is considered serious in a patient with hemophilia, the compartment pressure should be measured before making a decision regarding a fasciotomy. However, it is important to note that the use of factor VIII concentrates allows both emergency and elective surgery provided that adequate hematology backup is available. Splinting the elbow and wrist in flexion reduces the pressure in the volar compartments, protects the forearm from further trauma, and makes the patient more comfortable.
REFERENCES: Greene WB: Diseases related to the hematopoietic system, in Morrissy RT, Weinstein SL (eds): Lovell & Winter’s Pediatric Orthopaedics, ed 4. Philadelphia, Pa, Lippincott-Raven, 1996, pp 345-391.
Greene WB, McMillan CW: Nonsurgical management of hemophilic arthropathy, in Barr JS (ed): Instructional Course Lectures 38. Park Ridge, Ill, American Academy of Orthopaedic Surgeons, 1989, pp 367-381.
Naranja RJ Jr, Chan PS, High K, Esterhai JL Jr, Heppenstall RB: Treatment considerations in patients with compartment syndrome and an inherited bleeding disorder. Orthopedics 1997;20:706-711.

Question 100

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

Explanation

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

Full Question & Answer Text (for Search Engines)

Question 1:

A relative contraindication for anteromedial tibial tubercle transfer for patellar instability is arthrosis in what portion of the patella?

Options:

Lateral
Lateral and inferior
Central
Medial
Medial and proximal

Correct Answer: Medial and proximal

Explanation:

Question 2:

Options:

lateral retinacular release and medial reefing.
patellar tendon transfer medially.
lateral release and patellar tendon transfer.
femoral and tibial derotation osteotomies.
continued observation.

Correct Answer: continued observation.

Explanation:

Question 3:

Options:

Subscapularis failure
Frozen shoulder
Recurrent instability
Loose body
Chondrolysis

Correct Answer: Chondrolysis

Explanation:

DISCUSSION: Postshoulder stabilization chondrolysis is a rare but devastating complication. It has been implicated with the use of the radiofrequency heat probe in some patients.
REFERENCES: Levine WN, Clark AM Jr, D’Alessandro DF, et al: Chondrolysis following arthroscopic thermal capsulorrhaphy to treat shoulder instability: A report of two cases. J Bone Joint Surg Am 2005;87:616-621.
Petty DH, Jazrawi LM, Estrada LS, et al: Glenohumeral chondrolysis after shoulder arthroscopy: Case reports and review of the literature. Am J Sports Med 2004;32:509-515.

Question 4:

What is the most common location for localized pigmented villonodular synovitis (PVNS) to occur?

Options:

Ankle
Anterior knee
Posterior knee
Hip
Elbow

Correct Answer: Anterior knee

Explanation:

DISCUSSION: Localized PVNS is a form of the disease in which synovial proliferation is restricted to one area of a joint and causes the formation of a small mass-like lesion. The true incidence of this is unknown but is probably less common than the diffuse form of the disease. PVNS presents as a usually painful discrete mass. The anterior compartment of the knee is the most common location.
REFERENCES: Tyler WK, Vidal AF, Williams RJ, et al: Pigmented villonodular synovitis.
J Am Acad Orthop Surg 2006;14:376-385.
Kim SJ, Shin SJ, Choi NH, et al: Arthroscopic treatment for localized pigmented villonodular synovitis of the knee. Clin Orthop Relat Res 2000;379:224-230.

Question 5:

Options:

Irrigation and debridement of the cystic lesion and 6 weeks of IV antibiotics
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
Complete resection of the infected portion of bone, placement of an external fixator to stabilize the tibia, and 6 weeks of IV antibiotics
Amputation
Local debridement of bone and the overlying skin and soft tissues, 6 weeks of IV antibiotics, and free-flap wound coverage

Correct Answer: 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

Explanation:

DISCUSSION: 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.
REFERENCES: 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.
Beals RK, Bryant RE: The treatment of chronic open osteomyelitis of the tibia in adults.
Clin Orthop Relat Res 2005;433:212-217.

Question 6:

What strategy has proven most effective in preventing transmission of methicillin-resistant Staphylococcus aureus among teammates? Review Topic

Options:

Separate players with infections in a separate locker room or changing area.
Treat teammates of the infected player with prophylactic antibiotics.
Cover any skin lesions with occlusive dressing during sporting activity.
Ban players with infections from any team event.

Correct Answer: Cover any skin lesions with occlusive dressing during sporting activity.

Explanation:

Question 7:

Options:

Malignant fibrous histiocytoma
Liposarcoma
Synovial cell sarcoma
Leiomyosarcoma
Clear cell sarcoma

Correct Answer: Liposarcoma

Explanation:

DISCUSSION: The images show a complex, lobular lesion of the thigh that has signal characteristics that follow fat. The size of the lesion, the areas of stranding within the mass, along with mild uptake on the gadolinium sequences and the mild edema within the lesion on the T
2
-weighted image make liposarcoma the most likely diagnosis and simple intramuscular lipoma far less likely. All other diagnoses listed would not follow fat characteristics shown on the MRI sequences.
REFERENCE: Sanders TG, Parsons TW: Radiographic imaging of musculoskeletal neoplasia. Cancer Control 2001;8:221-231.

Question 8:

Which of the following is considered a specific advantage of using COX-2 inhibitors over COX-1 inhibitors?

Options:

Conversion of arachidonic acid to prostaglandins
Higher degree of efficacy
Does not affect platelet function and can be used during the perioperative period
Can be used in patients with congestive heart failure and renal disease
High levels of COX-2 (cyclooxygenase) found in normal tissue

Correct Answer: Does not affect platelet function and can be used during the perioperative period

Explanation:

DISCUSSION: Inflammation is mediated through two isoforms of cyclooxygenase that convert arachidonic acid to prostaglandins. Selectivity, but not specificity, is one of the unique characteristics of this process that has been able to provide more protection from the effects of gastric mucosal alterations using the COX-2 selective inhibitors. The use of COX-1 selective inhibitors is associated with side effects such as ulcerative conditions and platelet interference, both of which have been difficult to control in the past until the advent of the COX-2 inhibitors. PGE
2
inhibition by COX-1 in the intestinal track can then be bypassed, thereby reducing ulceration complications associated with use of nonsteroidal anti-inflammatory drugs.
REFERENCES: Lane JM: Anti-inflammatory medications: Selective COX-2 inhibitors. J Am Acad Orthop Surg 2002;10:75-78.
Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002.
Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000.

Question 9:

Options:

compartment syndrome
infection
anterior knee pain
nonunion
malunion

Correct Answer: compartment syndrome

Explanation:

Question 10:

Options:

Continued immobilization in a semi-rigid cervical orthosis for 6 to 8 weeks
Posterior occipital-cervical fusion with iliac crest bone graft
Open reduction and internal fixation of the odontoid process with an anterior odontoid screw
Resection of the odontoid process through a transoral approach
Reduction with Gardner-Wells tong traction and 6 weeks of skeletal traction

Correct Answer: Open reduction and internal fixation of the odontoid process with an anterior odontoid screw

Explanation:

DISCUSSION: Odontoid fractures can be classified based on the anatomic position of the fracture within the dens itself. Type I is an oblique fracture through the upper part of the odontoid process. Type II is a fracture that occurs at the base of the odontoid as it attaches to the body of C2; type III occurs when the fracture line extends through the body of the axis. Type 1 fractures typically can be treated nonsurgically with 6 to 8 weeks of immobilization with a semi-rigid cervical orthosis. Nondisplaced, deep type III fractures generally are treated with skeletal halo fixation. Deep, displaced, and angled type III fractures can be treated with closed reduction and skeletal halo fixation. Shallow type III fractures are sometimes amenable to anterior odontoid screw fixation. Type II fractures can be managed nonsurgically or surgically. Treatment options include halo immobilization, internal fixation (odontoid screw fixation), and posterior atlantoaxial arthrodesis. Management with the halo vest usually is considered if the initial dens displacement is less than 6 mm, the reduction is performed within 1 week of the injury and is able to be maintained, and the patient is younger than age 60 years. Halo vest immobilization can lead to a healing rate of more than 90%. Posterior surgical fusion techniques provide high fusion success rates but do so at the expense of cervical rotation. Up to 50% of rotation is lost with these techniques. Anterior odontoid single screw fixation is often tolerated better than skeletal halo fixation and also is noted to preserve the normal rotation at C1/C2. Studies have shown less of a malunion and nonunion rate in the treatment of type II odontoid fractures with anterior odontoid screw fixation. Osteoporosis, short neck and barrel-chested anatomy, and fractures that are more than 4 weeks old preclude anterior odontoid fixation.
REFERENCES: Shilpakar S, McLaughlin MR, Haid RW Jr, et al: Management of acute odontoid fractures: Operative techniques and complication avoidance. Neurosurg Focus 2000;8:e3.
Subach BR, Morone MA, Haid RW Jr, et al: Management of acute odontoid fractures with single-screw anterior fixation. Neurosurgery 1999;45:812-819.
Fountas KN, Kapsalaki EZ, Karampelas I, et al: Results of long-term follow-up in patients undergoing anterior screw fixation for type II and rostral type III odontoid fractures. Spine 2005;30:661-669.

Question 11:

Options:

You and your spouse attend dinner at a local restaurant with the local representative to discuss the Keyhole Genuflex knee.
Keyhole pays your tuition to attend a CME course sponsored by the American Association of Hip & Knee Surgeons where both the Genuflex and the competing Styph total knee are discussed and demonstrated.
Keyhole will pay your expenses to attend a workshop at their company headquarters, to learn how to implant the Genuflex knee and to see how the implant is manufactured and tested.
Keyhole will pay you $500 for each knee that you implant if you switch from your current total knee system.
After you have implanted 25 Genuflex knees, Keyhole will list you on their website as a consultant, pay you a consulting fee of $5,000 per year, and invite you to a golf tournament for their consultants at a resort.

Correct Answer: Keyhole will pay your expenses to attend a workshop at their company headquarters, to learn how to implant the Genuflex knee and to see how the implant is manufactured and tested.

Explanation:

Question 12:

All of the following have been shown to negatively affect clinical outcomes in treating displaced acetabular fractures, EXCEPT:

Options:

Increased age
Intraoperative complications
Ipsilateral femoral head injury
Involvement of both columns
Non-anatomic fracture reduction

Correct Answer: Increased age

Explanation:

Question 13:

Which of the following nerves is susceptible to entrapment near the calcaneal attachment site of the plantar fascia and can mimic or co-exist with plantar fasciitis?

Options:

First branch of the lateral plantar nerve
Dorsal cutaneous branch of the superficial peroneal nerve
Medial calcaneal branch of the posterior tibial nerve
Lateral branch of the medial plantar nerve
Communicating branch of the fourth common digital nerve

Correct Answer: First branch of the lateral plantar nerve

Explanation:

Question 14:

Options:

Fluid and electrolyte imbalance
Increased bleeding time
Impaired liver function
Lowered oxygen requirements
Splenomegaly

Correct Answer: Fluid and electrolyte imbalance

Explanation:

Question 15:

Options:

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

Correct Answer: Debride and exchange polyethylene

Explanation:

Question 16:

Which of the following statements best describes synovial fluid?

Options:

Erythrocytes are present at one tenth the normal concentration of blood.
White blood cells are present at one tenth the normal concentration of blood.
Synovial fluid is produced by type A synoviocytes.
Synovial fluid exhibits non-Newtonian fluid characteristics.
Synovial fluid contains similar concentrations of clotting factors as serum.

Correct Answer: Synovial fluid exhibits non-Newtonian fluid characteristics.

Explanation:

Question 17:

Options:

myelography with CT.
spinal cord-evoked potentials.
repeat physical examinations.
MRI.
electromyography and nerve conduction velocity studies.

Correct Answer: repeat physical examinations.

Explanation:

DISCUSSION: The patient has spinal shock. Steroid administration and MRI are appropriate therapeutic and diagnostic procedures. Myelography with CT is of little value unless there is an unusual skeletal variant. Spinal cord-evoked potentials have no value. The best method to determine the patient’s neurologic recovery is repeated physical examinations over the first 48 to 72 hours.
REFERENCES: Spivak JM, Connolly PF (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 183-184.
Herkowitz HN, Garfin SR, Eismont FJ: Rothman-Simone The Spine, ed 5. Philadelphia, PA, Saunders Elsevier, 2006, pp 1185-1194.

Question 18:

In addition to the radiographic features seen in Figures 49a and 49b, this patient will most likely have which of the following findings?

Options:

Microcephaly
1,25 dihydroxy vitamin D deficiency
Normal dentition
Anemia
Developmental delays

Correct Answer: Anemia

Explanation:

Question 19:

Early postoperative infections following primary total hip arthroplasty are most likely caused by which organism?

Options:

Staphylococcus epidermidis
Streptococcus viridans
Propionibacterium acnes
Staphylococcus aureus

Correct Answer: Staphylococcus aureus

Explanation:

Question 20:

Figure 37 shows the T2-weighted MRI scan of the hip joint. What structure is labeled A?

Options:

Ischiofemoral ligament
Ligamentum teres
Obturator internus
Piriformis
Coccygeus

Correct Answer: Obturator internus

Explanation:

Question 21:

Options:

no weight bearing.
weight bearing as tolerated in a hard-soled shoe.
a short leg walking cast.
second metatarsophalangeal joint debridement and metatarsal osteotomy.
a longitudinal arch support with metatarsal head relief.

Correct Answer: a short leg walking cast.

Explanation:

DISCUSSION: Freiberg’s infraction is believed to be an osteochondrosis of the second metatarsal head. It is the only osteochondrosis that has a predilection for females. The typical patient is an athletically active adolescent female. The radiograph shows stage II disease wherein reossification is occurring; it is at this time that the second metatarsal head is most susceptible to deformation. Therefore, initial management should consist of a short leg
walking cast.
REFERENCE: Mann RA, Coughlin MJ: Keratotic disorders of the plantar skin, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 413-415.

Question 22:

Options:

Examination would likely reveal a short neck, low posterior hairline and limited neck motion.
Serum human leukocyte antigen B27 is likely to be positive.
He is likely to be of Japanese descent.
The disease is defined by flowing ossification of the anterior longitudinal ligament at 4 consecutive levels.
Rheumatoid factor is likely to be positive.

Correct Answer: Rheumatoid factor is likely to be positive.

Explanation:

Question 23:

At the time of revision knee arthroplasty, a surgeon performs a rectus snip to gain exposure to the knee. When compared with a standard parapatellar approach, what is the expected outcome?

Options:

Improvement in range of motion
Reduction in range of motion
Increase in extensor mechanism lag
No differences in motion and strength

Correct Answer: No differences in motion and strength

Explanation:

DISCUSSION:
Rectus snip during total knee arthroplasty has no effect on motion or strength at long-term follow-up. It has not been associated with extensor mechanism lag.

Question 24:

A 16-year-old boy sustains a twisting injury to the left knee while wrestling. MRI scans are shown in Figures 22a through 22c. What is the most likely diagnosis?

Options:

Anterior cruciate ligament rupture
Posterior cruciate ligament rupture
Bucket-handle medial meniscus tear
Lateral meniscus tear
Osteochondral lesion

Correct Answer: Bucket-handle medial meniscus tear

Explanation:

DISCUSSION: The MRI scans show a displaced bucket-handle medial meniscus tear that can be visualized on coronal, sagittal, and axial views. The sagittal view shows the typical “double posterior cruciate ligament sign,” in which the low-signal bucket-handle fragment parallels the normal low-signal posterior cruciate ligament. The coronal and axial images both show the displaced medial meniscus in the notch.
REFERENCES: Sanders TG, Miller MD: A systematic approach to magnetic resonance imaging interpretation of sports medicine injuries of the knee. Am J Sports Med 2005;33:131-148.
Miller TT: Magnetic resonance imaging of the knee, in Insall JN, Scott WN (eds): Surgery of the Knee, ed 4. Philadelphia, PA, Churchill Livingstone, 2006, vol 1, pp 201-224.

Question 25:

A 4-month-old infant is unable to flex her elbow as a result of an obstetrical brachial plexus palsy. This most likely illustrates a predominate injury to what structure? Review Topic

Options:

C4
Upper trunk
Posterior cord
Lateral cord
Musculocutaneous nerve

Correct Answer: Upper trunk

Explanation:

Question 26:

Based on the MR arthrogram of the elbow shown in Figure 8, which of the following structures is torn?

Options:

Common flexor tendon
Anconeus
Radial collateral ligament
Ulnar collateral ligament
Lateral ulnar collateral ligament

Correct Answer: Ulnar collateral ligament

Explanation:

Question 27:

A 34-year-old man sustained a tibial fracture in a motorcycle accident. What perioperative variable is associated with the greatest relative risk for reoperation to achieve bone union?

Options:

Gender
Delay in initial surgical treatment
Use of nonsteroidal anti-inflammatory drugs
Smoking
Cortical contact of less than or equal to 50%

Correct Answer: Cortical contact of less than or equal to 50%

Explanation:

Question 28:

Figures 4a and 4b are the radiographs of an isolated injury. What is the next most appropriate step in management?

Options:

CT
MRI
Closed reduction and casting
Application of a spanning external fixator
Immediate open reduction and internal fixation (ORIF)

Correct Answer: Application of a spanning external fixator

Explanation:

Question 29:

Options:

humeral head replacement with rotator cuff repair.
humeral head replacement without rotator cuff repair.
arthrodesis of the shoulder.
total shoulder replacement with rotator cuff repair.
total shoulder replacement without rotator cuff repair.

Correct Answer: total shoulder replacement with rotator cuff repair.

Explanation:

Question 30:

Radiating pain associated with a posterolateral thoracic disk herniation typically follows what pattern?

Options:

Extending down the spine into the lumbosacral region
Down the inner aspect of either upper extremity
Cephalad up to the cervicothoracic junction
Around or through the chest to the anterior wall
Down the contralateral lower extremity

Correct Answer: Around or through the chest to the anterior wall

Explanation:

DISCUSSION: Although symptomatic thoracic disk herniations can affect more caudal structures, even to the point of paralysis, the pattern of radiating pain has been described as either following the dermatomal band around the chest or feeling to the patient as if the pain passes straight anteriorly to the chest wall.
REFERENCE: Skubic JW, Kostuik JP: Thoracic pain syndromes and thoracic disc herniation, in Frymoyer JW (ed): The Adult Spine: Principles and Practice. New York, NY, Raven Press, 1991, pp 1443-1464.

Question 31:

Clinical evidence suggests that grafts for replacing a torn anterior cruciate ligament often stretch after surgery. What is the most probable mechanism for this behavior?

Options:

Gross failure at the attachment sites
Fatigue failure of the ligament tissue
Creep of the graft material
Water absorption by the graft material
Elastic stretch of collagen fibers

Correct Answer: Creep of the graft material

Explanation:

DISCUSSION: The stretching of the graft occurs over time as the graft is loaded. Time-dependent deformation under load is called creep and is common in viscoelastic materials such as ligament tissue. Creep can occur under both static and cyclic load conditions; time-dependent deformation will occur as long as load is applied to the tissue. Similarly, when a graft is initially tensioned to a given deformation at surgery, the load generated in the graft will decrease over time; this behavior is called stress relaxation and also is indicative of a viscoelastic material. Water content may affect the viscoelastic properties by changing the friction between collagen fibers, but studies have shown little difference in water content between grafts and normal ligaments. Fatigue failures may manifest themselves through damage to the ligament tissue, but this would require higher loads than are routinely experienced by grafts. Elastic stretch is recoverable and, therefore, does not contribute to a permanent stretch. Similarly, gross failure at the attachment would not cause a stretch, but rather a catastrophic instantaneous instability.
REFERENCES: Boorman RS, Thornton GM, Shrive NG, et al: Ligament grafts become more susceptible to creep within days after surgery. Acta Orthop Scand 2002;73:568-574.
Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science: Biology and Biomechanics of the Musculoskeletal System, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 596-609.
Lu L, Kaufman KR, Yaszemski MJ: Biomechanics, in Einhorn TA, O’Keefe RJ,
Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 32:

Options:

Repeat epidural steroid injections
Wide lumbar laminectomy
Microdiskectomy from either a midline approach or far lateral approach
Referral to pain management
Minimally invasive posterior lumbar interbody fusion

Correct Answer: Microdiskectomy from either a midline approach or far lateral approach

Explanation:

DISCUSSION: The CT scan reveals a right-sided lateral disk protrusion at L3-4 that has been symptomatic for more than 4 months despite appropriate nonsurgical management. Relative surgical indications include persistent radiculopathy despite an adequate trial of nonsurgical management, recurrent episodes of sciatica, persistent motor deficit with tension signs and pain, and pseudoclaudication caused by underlying stenosis. Whereas studies have shown improvement in patients with sciatica from a lumbar disk herniation treated either nonsurgically or surgically, those undergoing surgical treatment had an overall greater improvement of symptoms.
REFERENCES: Weinstein JN, Lurie JD, Tosteson TD, et al: Surgical vs nonoperative treatment for lumbar disk herniation: The Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA 2006;296:2451-2459.
Yorimitsu E, Chiba K, Toyama Y, et al: Long-term outcomes of standard discectomy for lumbar disc herniation: A follow-up study of more than 10 years. Spine 2001;26:652-657.

Question 33:

Options:

disruption of the sympathetic nerves during anterior lumbar exposure.
traction on the parasympathetic nerve at the L4-5 level.
not related to the surgical dissection.
injury to the pudendal nerves in the anterior sacral region during dissection at the L5-S1 level.
sexual dysfunction secondary to retrograde ejaculation.

Correct Answer: not related to the surgical dissection.

Explanation:

Question 34:

Bioabsorbable polymers are used in a wide range of orthopaedic devices, including anchors, staples, pins, plates, and screws. What is the primary drawback for bioabsorbable implants?

Options:

High cost
Increased rates of infection
High elastic modulus
Brittleness
Foreign body reaction

Correct Answer: Foreign body reaction

Explanation:

DISCUSSION: A number of bioabsorbable polymers are used in orthopaedic applications, and all have in common reports of foreign body reactions, which occur in more than 50% of patients in some series. In general, the high cost of these polymers is offset by the elimination of a second surgery to remove the implant. Bioabsorbable polymers are low strength in comparison to metallic alloys but of sufficient strength for many orthopaedic applications. The elastic modulus is not as high as many other orthopaedic biomaterials, making them suitable for applications where lower stiffness is an asset.
REFERENCES: Ambrose CG, Clanton TO: Bioabsorbable implants: Review of clinical experience in orthopedic surgery. Ann Biomed Eng 2004;32:171-177.
Bergsma JE, de Bruijn WC, Rozema FR, et al: Late degradation tissue response to poly
(L-lactide) bone plates and screws. Biomaterials 1995;16:25-31.

Question 35:

Figures 86a through 86c are the radiographs and biopsy specimen of a 14-year-old boy who has had left knee pain for 4 weeks. What is the most likely diagnosis?

Options:

Chondroblastoma
Chondrosarcoma
Parosteal osteosarcoma
Osteoblastoma
Osteosarcoma

Correct Answer: Osteosarcoma

Question 36:

Options:

Strongly negative needle-shaped crystals
Weakly positive birefringent rhomboid-shaped crystals
Gross blood
Gram-positive cocci
Gram-negative rods

Correct Answer: Weakly positive birefringent rhomboid-shaped crystals

Explanation:

Question 37:

Changes to the properties of ultra-high molecular weight polyethylene with increasing irradiation dose include improved

Options:

resistance to oxidation.
ultimate tensile strength.
resistance to crack propagation.
fracture toughness.
volumetric wear.

Correct Answer: volumetric wear.

Explanation:

Question 38:

Options:

tighten as the knee extends past 10° of flexion.
tighten as the knee flexes past 90°.
loosen as the knee extends past 10° of flexion.
loosen as the knee flexes past 30°.
loosen as the knee flexes past 90°.

Correct Answer: tighten as the knee flexes past 90°.

Explanation:

Question 39:

Options:

Incision and drainage
Ice the ankle but don't let him play.
Topical antibiotics for 7 days with an occlusive dressing
Debridement in the training room followed by 5 days of oral antibiotics

Correct Answer: Incision and drainage

Explanation:

The clinical photograph shows a skin infection with an appearance consistent with methicillin-resistant
Staphylococcus aureus
. This infection should be clinically incised and allowed to drain and a course of antibiotics should follow. If this infection is not promptly treated with debridement, it likely will worsen and potentially spread to other teammates. Antibiotics are secondary to surgical debridement but are a necessary adjunct. Although this patient has a history of severe sprain, his malaise and skin appearance do not correlate with a ligament injury or fracture. Debridement in the training room is not appropriate and would likely not fully decompress the fluid collection.

Question 40:

Options:

Warfarin with a targeted international normalized ratio (INR) of 2.0 to 3.0 for 10 to 14 days
Low-molecular-weight heparin used for at least 3 days
Pneumatic compression sleeves used while the patient is in the hospital
Fondaparinux used for 5 to 7 days
Aspirin for 4 weeks

Correct Answer: Warfarin with a targeted international normalized ratio (INR) of 2.0 to 3.0 for 10 to 14 days

Explanation:

DISCUSSION: In the 2004 ACCP guidelines, there were three prophylactic regimens that received a grade 1A favorable recommendation. These included low-molecular-weight heparin, warfarin, or fondaparinux, as long as they are used for at least 10 days. If warfarin is used, the target INR should be 2.0 to 3.0, according to the guidelines. Pneumatic compression sleeves have gained popularity in the orthopaedic community but have not received a grade 1A rating from the ACCP at this time. Use of aspirin by itself is discouraged by the ACCP.
REFERENCE: Geerts WH, Pineo GF, Heit JA, et al: Prevention of venous thromboembolism: The seventh ACCP Conference on antithrombotic and thrombolytic therapy. Chest 2004;126:338S-400S.

Question 41:

Options:

Thompson
Cotton
Squeeze
Anterior drawer

Correct Answer: Cotton

Explanation:

DISCUSSION
Following ORIF of a known osseous injury, stress testing of the syndesmosis is recommended, especially for pronation-external rotation injuries. The Cotton test applies a laterally directed force to the fibula to assess for widening of the distal tibiofibular joint space. A positive Cotton test result indicates that syndesmotic stabilization is indicated. The Thompson test is used to determine Achilles tendon integrity. The squeeze test is a clinical, not intraoperative, assessment of syndesmotic injury. The anterior drawer test assesses the integrity of the anterior talofibular ligament.
RECOMMENDED READINGS
Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg. 2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882.
View Abstract at PubMed
Pakarinen H, Flinkkilä T, Ohtonen P, Hyvönen P, Lakovaara M, Leppilahti J, Ristiniemi J. Intraoperative assessment of the stability of the distal tibiofibular joint in supination-external rotation injuries of the ankle: sensitivity, specificity, and reliability of two clinical tests. J Bone Joint Surg Am. 2011 Nov 16;93(22):2057-61. doi: 10.2106/JBJS.J.01287. PubMed PMID:

Question 42:

Options:

Facet injections
Epidural steroid injection
MRI of the lumbar spine
Bed rest for 2 weeks with continued restrictions
Early return to activities as his symptoms allow

Correct Answer: Early return to activities as his symptoms allow

Explanation:

Question 43:

-What is the most appropriate next treatment step?

Options:

Open biopsy
Extension casting
CT scan of the chest
Blood culture and image-guided needle biopsy or aspiration

Correct Answer: Blood culture and image-guided needle biopsy or aspiration

Explanation:

DISCUSSION FOR QUESTIONS 7 AND 8
Based on the patient’s signs and symptoms, the most likely diagnosis is osteomyelitis of the spine. The imaging studies do not reveal a herniated disk, which would be unusual in someone of this age. Aneurysmal bone cysts would involve the posterior elements with a more expansive lesion of bone, whereas this lesion involves primarily the body and anterior column. Hemangioma would likely not be present with systemic signs or symptoms and has a more characteristic coarse trabecular pattern on radiographs and scans. Given the likelihood that this patient has osteomyelitis of the spine, blood cultures may yield an organism about 50% of the time. If cultures are negative, an image-guided biopsy is warranted. A diagnosis needs to be established before treatment such as extension casting or bracing is rendered. Open biopsy may still be needed if needle biopsy is not diagnostic, but this is not the first treatment option. A chest CT scan is not appropriate as a first step when a tumor is presumed and a diagnosis has not been established.

Question 44:

What percentage of bone weight is collagen?

Options:

1 5% to 10%
2 20% to 25%
3 50% to 60%
4 70% to 75%
90% to 95%

Correct Answer: 2 20% to 25%

Explanation:

Question 45:

Options:

Arthroscopic debridement alone of the partial rotator cuff tear
Repair of the partial rotator cuff tear and subacromial decompression
Arthroscopic debridement combined with subacromial decompression
Arthroscopic subacromial decompression
Biceps tenotomy

Correct Answer: Repair of the partial rotator cuff tear and subacromial decompression

Explanation:

DISCUSSION: Although arthroscopic debridement with or without subacromial decompression is a reasonable response, the patient has positive impingement signs. Several recent studies regarding the surgical treatment of partial rotator cuff tears have demonstrated good to excellent results after repair of tears involving more than 50% of the tendon thickness. This was shown specifically for bursal-sided tears and joint-side tears. Biceps tenotomy is not indicated in a young patient.
REFERENCES: Matava MJ, Purcell DB, Rudzki JR: Partial-thickness rotator cuff tears.
Am J Sports Med 2005;33:1405-1417.
Fukuda H: The management of partial-thickness tears of the rotator cuff. J Bone Joint Surg Br 2003;85:3-11.

Question 46:

Options:

Use of an abduction orthosis for 6 weeks
Modular exchange of the femoral head to a 36-mm head and a longer neck
Modular exchange of the polyethylene liner to a constrained acetabular insert
Revision and repositioning of the acetabular component and use of a 36-mm femoral head
A physical therapy program stressing abductor strengthening

Correct Answer: Revision and repositioning of the acetabular component and use of a 36-mm femoral head

Explanation:

Question 47:

There is a risk of impaired forearm rotation after tension band fixation of an olecranon fracture with which of the following?

Options:

Ipsilateral proximal humerus fracture
Protrusion of Kirschner wire fixation through the volar cortex of the proximal ulna
Use of ulnar intramedullary Kirschner wire fixation
Olecranon fracture comminution
Lack of triceps tendon repair

Correct Answer: Ipsilateral proximal humerus fracture

Explanation:

Question 48:

What is the most common associated pathology in patients who have suprascapular nerve entrapment secondary to ganglion cysts?

Options:

Glenohumeral arthritis
Fracture of the clavicle
Tear of the rotator cuff
Rupture of the long head of the biceps tendon
Superior labrum anterior and posterior (SLAP) lesion

Correct Answer: Superior labrum anterior and posterior (SLAP) lesion

Explanation:

Question 49:

Options:

- Administer IV fluids and then reassess vital signs before making further decisions
- Pelvic binder and IV fluids
- Pelvic binder and immediate transfusion
- Pelvic binder, IV fluids, type and cross-match, and then transfuse

Correct Answer: - Pelvic binder and immediate transfusion

Explanation:

Question 50:

When planning pin placement for external fixation of the tibia, what is the maximum extent of the knee capsular reflection from the subchondral joint line?

Options:

4 mm
6 mm
10 mm
14 mm
20 mm

Correct Answer: 14 mm

Explanation:

Question 51:

Figure 1 is the radiograph of a 31-year-old man who had left shoulder pain after a fall during a snowboarding jump. Residual displacement of 5 mm after closed reduction is most likely to result in

Options:

nonunion.
osteonecrosis.
altered rotator cuff mechanics.
normal shoulder function.

Correct Answer: altered rotator cuff mechanics.

Explanation:

Question 52:

Options:

open repair.
immobilization.
aspiration and steroid injection.
rest, ice, and rehabilitation.
tenotomy.

Correct Answer: rest, ice, and rehabilitation.

Explanation:

Question 53:

Which of the following factors has the most effect on the pullout strength of lumbar transpedicular screw fixation?

Options:

Depth of vertebral body penetration
Screw diameter
Percentage of pedicle filled by the screw
Presence of osteopenia
Tapping of the pedicle

Correct Answer: Presence of osteopenia

Explanation:

Question 54:

Figures 23a and 23b show the radiographs of a 75-year-old woman who sustained an injury to her nondominant hand. Initial treatment should consist of

Options:

closed reduction and splinting.
open reduction and internal fixation through a volar approach.
external fixation and Kirschner wire fixation.
intrafocal pinning and casting.
acceptance of alignment and bracing.

Correct Answer: closed reduction and splinting.

Explanation:

DISCUSSION: Definitive treatment decisions for displaced distal radius fractures in the elderly are based on a number of factors related to the fracture pattern and patient demographics. The first step in any treatment algorithm is a closed reduction and splinting with reassessment of alignment parameters. This is an extra-articular fracture with dorsal angulation. Low-demand elderly patients can be treated well with accepted minor malreduction.
REFERENCES: Handoll HH, Madhok R: Conservative interventions for treating distal radial fractures in adults. Cochrane Database Syst Rev 2003;2:CD000314.
Young CF, Nanu AM, Checketts RG: Seven-year outcome following Colles’ type distal radial fracture: A comparison of two treatment methods. J Hand Surg Br 2003;28:422-426.

Question 55:

Closed-chain exercise differs from open-chain exercise in which of the following ways?

Options:

Distal portion of the extremity is free during exercise
More commonly used in upper extremity exercise
Predictable movement is produced by co-contraction of muscles
Joint compression is decreased
Usually involves a single joint

Correct Answer: Predictable movement is produced by co-contraction of muscles

Explanation:

Question 56:

Options:

Semimembranosis tendonitis
Patellar tendonitis
Iliotibial band friction syndrome
Quadriceps tendonitis

Correct Answer: Patellar tendonitis

Explanation:

Question 57:

What approach should be chosen for the injury seen in Figure 67? Review Topic

Options:

Stoppa
Hardinge
Ilioinguinal
Watson Jones
Kocher-Langenbeck

Correct Answer: Kocher-Langenbeck

Explanation:

Question 58:

In a patient who has undergone fusion with instrumentation from T4 to the sacrum for adult scoliosis, at which site is a pseudarthrosis most likely to be discovered?

Options:

T4-T5
T7-T8
L2-L3
L4-L5
L5-S1

Correct Answer: L5-S1

Explanation:

DISCUSSION: Although pseudarthrosis can be found anywhere within the spine that has been fused using long multisegmental fixation to the sacrum, it most commonly occurs at the lumbosacral junction. The thoracolumbar junction is another common site of potential pseudarthrosis. In this location, the anatomy changes from lumbar transverse processes to thoracic through the transition zone, and overlying instrumentation often makes it difficult to obtain enough sound bone on decorticated bone to achieve a successful fusion.
REFERENCES: Saer EH III, Winter RB, Lonstein JE: Long scoliosis fusion to the sacrum in adults with nonparalytic scoliosis: An improved method. Spine 1990;15;650-653.
Kostuik JP, Hall BB: Spinal fusions to the sacrum in adults with scoliosis. Spine
1983;8:489-500.
Balderston RA, Winter RB, Moe JH, et al: Fusion to the sacrum for nonparalytic scoliosis in the adult. Spine 1986;11:824-829.

Question 59:

Options:

back muscle stretching and reduced weight in the backpack.
consultation with a pain management specialist.
MRI of the thoracic spine.
a technetium Tc 99m bone scan.
a thoracolumbosacral orthosis.

Correct Answer: back muscle stretching and reduced weight in the backpack.

Explanation:

DISCUSSION: Mild scoliosis is not a painful condition, but it usually presents during adolescence. Intermittent back pain is reported by 25% to 30% of adolescents whether or not scoliosis is present. Such pain is often attributed to muscle strain from tight muscles, poor posture, or heavy school backpacks. The clinician must distinguish typical pain (mild, intermittent, nonlimiting) from atypical pain. The latter requires more careful examination and imaging studies (bone scan or MRI) to determine the source of pain. The patient’s age and right thoracic curve pattern are typical for idiopathic scoliosis; therefore, imaging of the neuroaxis is not necessary to look for cord syrinx, tethering, or tumor. Brace treatment is not required for this small curve unless future progression is demonstrated.
REFERENCES: Ramirez N, Johnston CE, Browne RH: The prevalence of back pain in children who have idiopathic scoliosis. J Bone Joint Surg Am 1997;79:364-368.
Hollingworth P: Back pain in children. Br J Rheum 1996;35:1022-1028.
Siambanes D, Martinez JW, Butler EW, et al: Influence of school backpacks on adolescent back pain. J Pediatr Orthop 2004;24:211-217.

Question 60:

- Figures 59a and 59b show the plain radiographs, and Figures 59c and 59d show the CT scan of a 77-year-old woman who has had pain in her back and both buttocks for the past 6 months. She reports that the pain radiates down her right thigh and leg when she is standing. What is the most likely diagnosis?

Options:

Lumbar spinal stenosis
Metastatic disease of the spine
Rheumatoid lumbar spondylitis
Isthmic spondyloloisthesis
Degenerative spondylolisthesis at L4-5 and L5-S1

Correct Answer: Lumbar spinal stenosis

Explanation:

Question 61:

Which of the following actions increases radiation exposure to patients and personnel when using fluoroscopy?

Options:

The use of lead glasses, thyroid shield, and a lead apron with a equivalent lead thickness of 0.25 mm
Orienting the cathode ray tube beneath the patient with the image intensifier receptor as close to the patient as possible
Limiting the beam on time to only what is clinically important
The use of continuous fluoroscopy to ensure proper placement of implants
Orienting the beam in the opposite direction of the working team and keeping the team outside a 6-foot radius from the fluoroscopy machine

Correct Answer: The use of continuous fluoroscopy to ensure proper placement of implants

Explanation:

Question 62:

Options:

rest from throwing activities.
a subacromial corticosteroid injection.
open reduction and internal fixation.
arthroscopic labral repair.
biopsy of the proximal humerus.

Correct Answer: rest from throwing activities.

Explanation:

Question 63:

Options:

Technetium Tc 99m bone scan
Intravenous antibiotics
Oral antibiotics
CT of the hips
Aspiration of the left hip

Correct Answer: Aspiration of the left hip

Explanation:

DISCUSSION: Examination reveals an irritable hip, creating a differential diagnosis of transient synovitis versus pyogenic hip arthritis. Kocher and associates described four criteria to help predict the presence of infection: inability to bear weight, fever, ESR of more than 40 mm/h, and a peripheral WBC count of more than 12,000/mm
P
3
P
. This patient meets three of the four criteria, with a positive predictive value of 73% to 93% for joint infection. Therefore, aspiration of the hip is warranted, with a high likelihood that emergent hip arthrotomy will be indicated. Ideally, intravenous antibiotics should be administered after culture material has been obtained from needle aspiration of the hip. An urgent bone scan is better indicated as a screening test for sacroiliitis or diskitis. If the arthrocentesis proves negative, CT or MRI of the pelvis may be indicated to rule out a pelvic or psoas abscess.
REFERENCES: Del Beccaro MA, Champoux AN, Bockers T, et al: Septic arthritis versus transient synovitis of the hip: The value of screening laboratory tests. Ann Emerg Med 1992;21:1418-1422.
Kocher MS, Mandiga R, Zurakowski D, et al: Validation of a clinical prediction rule for the differentiation between septic arthritis and transient synovitis of the hip in children. J Bone Joint Surg Am 2004;86:1629-1635.
Kocher MS, Zurakowski D, Kasser JR: Differentiating between septic arthritis and transient synovitis of the hip in children: An evidence-based clinical prediction algorithm. J Bone Joint Surg Am 1999;81:1662-1670.

Question 64:

Options:

excision of the distal clavicle.
open reduction and internal fixation with intramedullary partial threaded pins.
open reduction and internal fixation with a reconstruction plate, screws, and bone grafting.
bone grafting and use of heavy sutures to secure the clavicle to the coracoid.
observation and nonsteroidal anti-inflammatory drugs.

Correct Answer: observation and nonsteroidal anti-inflammatory drugs.

Explanation:

Question 65:

Options:

An unknown prognosis until they can participate in an examination.
Higher rates of neurologic deficit and mortality than other same-age people.
Higher rates of neurologic deficit than other same-age people, but comparable mortality rates.
Similar rates of neurologic deficit and mortality as other same-age people.

Correct Answer: Higher rates of neurologic deficit and mortality than other same-age people.

Explanation:

DISCUSSION
Several studies have found that rates of neurologic deficit and mortality are higher for patients with ankylosing spondylitis and a spinal fracture than for age-matched controls. The 2011 work of Schoenfeld and associates, which directly compared patients with cervical fractures in ankylosed spines to age-and sex-matched controls who also had cervical fractures but no ankylosing condition, demonstrated that those with ankylosing spondylitis were at elevated risk for mortality for up to 2 years after sustaining a fracture. In a study by Westerveld and associates, the rate of neurologic deficit among patients with ankylosing spondylitis and a spinal fracture was 57.1% compared to 12.6% among controls.
RECOMMENDED READINGS
Westerveld LA, van Bemmel JC, Dhert WJ, Oner FC, Verlaan JJ. Clinical outcome after traumatic spinal fractures in patients with ankylosing spinal disorders compared with control patients. Spine J. 2014 May 1;14(5):729-40. doi: 10.1016/j.spinee.2013.06.038. Epub 2013 Aug 27. PubMed PMID: 23992936.
View
Abstract at PubMed
Schoenfeld AJ, Harris MB, McGuire KJ, Warholic N, Wood KB, Bono CM. Mortality in elderly patients with hyperostotic disease of the cervical spine after fracture: an age- and sex-matched study. Spine J. 2011 Apr;11(4):257-64. doi: 10.1016/j.spinee.2011.01.018. Epub 2011 Mar 5. PubMed PMID: 21377938.
View
Abstract at PubMed

Question 66:

What cardiac condition causes most upper extremity emboli?

Options:

Atrial fibrillation
Viral cardiomyopathy
Valvular disease
Atrial septal defect

Correct Answer: Atrial fibrillation

Explanation:

Question 67:

- Which of the following neurovascular structures is at greatest risk during the introduction of acetabular component fixation screws during total hip replacement?

Options:

Sciatic nerve
Superior gluteal artery
Profunda femoris artery
Femoral artery and nerve
External iliac artery and vein

Correct Answer: External iliac artery and vein

Explanation:

Question 68:

03 A 26-year-old woman has chronic toe pain after hitting a bedpost 3 months ago. A radiograph is shown in Figure 27. Her injury represents an avulsion of the

Options:

lumbrical insertion.
extensor digitorum brevis.
extensor digitorum longus.
extensor hallucis longus.
flexor digitorum longus.
back answer Question 105.03

Correct Answer: extensor digitorum longus.

Explanation:

Question 69:

Which of the following is considered the treatment of choice for a chondroblastoma of the proximal tibial epiphysis without intra-articular extension?

Options:

Observation
Curettage and bone grafting
Wide local excision
Wide local excision and radiation therapy
Radiation therapy only

Correct Answer: Curettage and bone grafting

Explanation:

Question 70:

Options:

Albumin of 3.4
Active osteomyelitis
ABI of 0.4 for the posterior tibial artery
Transcutaneous oxygen pressure of 45
Peripheral neuropathy

Correct Answer: Albumin of 3.4

Explanation:

Question 71:

Options:

Femoroacetabular impingement (FAI)
Osteoarthritis of the sacroiliac joint
Intra-articular loose body
Trochanteric bursitis

Correct Answer: Femoroacetabular impingement (FAI)

Explanation:

This clinical scenario describes a patient with FAI attributable to pincer (acetabular) deformity. This form of FAI, which involves prominence of the anterosuperior acetabular lip, may be more common among women. Decreased range of motion and pain occur secondary to the abutment of the femoral head against the acetabular labrum and rim. Hip flexion, combined with adduction and internal rotation, recreates this contact and causes pain, but CAM or pincer etiology remains unknown. The differential diagnosis of hip pain in a young athlete includes femoral neck stress reaction/fracture, sacroiliac arthritis, intra-articular loose body, trochanteric bursitis, osteitis pubis, and hernia. No information presented in this scenario suggests any of these causes. Diagnosis of FAI is best performed via MR imaging, with an arthrogram increasing the sensitivity and specificity for labral pathology. Ultrasonography may be useful in the diagnosis of dysplasia or for dynamic assessment of a snapping hip, but ultrasonography is not commonly used to diagnose labral pathology. Although concomitant chondral lesions of the femoral head are uncommon, the forced leverage of the anterosuperior femoral neck upon the anterior acetabulum may result in a “contra-coup” chondral injury on the posteroinferior acetabulum. This is the most common location of chondral lesions in this scenario. Without bony resection to prevent further impingement, this patient will continue to experience symptoms. Because there is no evidence of femoral neck prominence (CAM lesion), there is no indication for osteoplasty of the femoral neck; resection of the pincer lesion is necessary. This will often require take-down of the labrum in this location. If possible, iatrogenic or traumatic labral tears should subsequently be repaired after pincer debridement because the labrum has
important functions for hip stability and maintenance of the suction seal of the joint.

Question 72:

In a diagnostic test, the proportion of individuals who are truly free of a designated disorder identified by the test is known as

Options:

specificity.
sensitivity.
accuracy.
positive predictive value.
negative predictive value.

Correct Answer: specificity.

Explanation:

Question 73:

A neurologic injury at T11-L2 with loss of bowel and bladder control is best described as what syndrome?

Options:

Anterior cord
Central cord
Posterior cord
Conus medullaris
Cauda equina

Correct Answer: Conus medullaris

Explanation:

Question 74:

Options:

Sciatic nerve decompression
Arthroscopic labral repair
Repair to the intertrochanteric crest
Repair to the femoral shaft
Repair to the ischial tuberosity

Correct Answer: Sciatic nerve decompression

Explanation:

Question 75:

Options:

infection. B. instability. C. loosening.
periprosthetic fracture.

Correct Answer: periprosthetic fracture.

Explanation:

Question 76:

Options:

entrapment of the superior laryngeal nerve during ligation of the superior thyroid artery.
stretch of the recurrent laryngeal as it enters the esophageal-tracheal groove.
injury to the vocal cord during endotracheal intubation.
displacement of the larynx against the endotracheal tube by retraction.
retractor pressure on the laryngeal nerve in the esophageal groove.

Correct Answer: displacement of the larynx against the endotracheal tube by retraction.

Explanation:

Question 77:

Options:

Renal ultrasound
Blood cultures
Flexion-extension cervical spine radiographs
Platelet count

Correct Answer: Renal ultrasound

Explanation:

Question 78:

Which examination finding points toward a brachial plexus injury rather than root avulsion?

Options:

Winging of the scapula
Intact rhomboid function
A biceps with 0/5 strength
An ipsilateral clavicle fracture

Correct Answer: Intact rhomboid function

Explanation:

Question 79:

During treatment of rupture of the subscapularis tendon with associated biceps instability, treatment of the biceps tendon should include which of the following?

Options:

Tenosynovectomy
Recentering
Deepening of the bicipital groove
Tenodesis or tenotomy
Lysis of sheath adhesion

Correct Answer: Tenodesis or tenotomy

Explanation:

DISCUSSION: With subscapularis tendon ruptures that have biceps tendon pathology, treatment with tenodesis or tenotomy has improved clinical results. Subluxation or dislocation of the biceps tendon is common with subscapularis rupture. Dislocation of the biceps can occur either beneath the tendon, within the tendon, or extra-articularly. In all cases, the restraints to medial translations of the biceps have been disrupted. Attempts at recentering the biceps have not been successful, and clinical results appear to be improved when tenodesis or tenotomy is employed in the treatment of the unstable biceps associated with subscapularis tears.
REFERENCES: Edwards TB, Walch G, Sirvenaux F, et al: Repair of tears of the subscapularis: Surgical technique. J Bone Joint Surg Am 2006;88:1-10.
Deutsch A, Altchek DW, Veltri DM, et al: Traumatic tears of the subscapularis tendon: Clinical diagnosis, magnetic resonance imaging findings, and operative treatment. Am J Sports Med 1997;25:13-22.
Edwards TB, Walch G, Sirveaux F, et al: Repair of tears of the subscapularis. J Bone Joint Surg Am 2005;87:725-730.

Question 80:

Options:

Continued skin traction
Skeletal traction of both femurs
External fixation of both femurs
Intramedullary nailing of one femur and external fixation and delayed nailing for the other femur
Intramedullary nailing of both femurs

Correct Answer: Intramedullary nailing of both femurs

Explanation:

DISCUSSION: Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm.
REFERENCES: Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.
Pape HC, Zelle BA, Hildebrand F, et al: Reamed femoral nailing in sheep: Does irrigation and aspiration of intramedullary contents alter the systemic response? J Bone Joint Surg Am 2005;87:2515-2522.

Question 81:

This image represents the end stage of an uncompensated rotator cuff tear.

Options:

Figure 59a is the CT image of an 86-year-old woman with acromiohumeral distance of less than 2 mm, night pain, and an inability to actively raise the affected arm above shoulder level.
Figure 59b is the radiograph of a 45-year-old man with acromiohumeral distance equal to 7 mm. He is able to actively raise his arm above shoulder level, has lateral arm pain,
and abduction and external rotation weakness. 56
Figures 59c and 59d are the radiographs of a 72-year-old man with night pain and reduced range of motion.

Correct Answer: Figure 59a is the CT image of an 86-year-old woman with acromiohumeral distance of less than 2 mm, night pain, and an inability to actively raise the affected arm above shoulder level.

Explanation:

DISCUSSION
Axillary lateral and anteroposterior (AP) images of the right shoulder (Figures 59c and 59d) reveal osteoarthrosis of the glenohumeral joint, which typically is not associated with significant rotator cuff pathology. An examination often shows limitations in range of motion, crepitance, and pain with motion. An AP radiographic image of the right shoulder (Figure 59b) reveals proximal humeral migration, which normally correlates with rotator cuff tear size. Tears extending into the infraspinatus tendon are associated with more humeral migration than is seen with isolated supraspinatus tears. Presenting complaints are usually of pain and weakness. Examination findings include subacromial crepitance and weakness during rotator cuff testing. Rarely, this may be associated with pseudoparalysis in large uncompensated rotator cuff tears. The CT image of the right shoulder (Figure 59a) shows superior migration of the humerus with respect to the glenoid surface and end-stage
degenerative changes at the glenohumeral joint. These changes are classified as rotator cuff arthropathy. Pain and weakness are common, as is the presence of pseudoparalysis and limited range of motion.
RECOMMENDED READINGS
Kelly JD Jr, Norris TR. Decision making in glenohumeral arthroplasty. J Arthroplasty. 2003 Jan;18(1):75-82. Review. PubMed PMID: 12555187.
View Abstract at PubMed
Keener JD, Wei AS, Kim HM, Steger-May K, Yamaguchi K. Proximal humeral migration in shoulders with symptomatic and asymptomatic rotator cuff tears. J Bone Joint Surg Am. 2009 Jun;91(6):1405-13. doi: 10.2106/JBJS.H.00854. PubMed PMID:

Question 82:

Options:

Independent 2-sample t test
Analysis of variance (ANOVA)
Chi-square test
Fisher's exact test

Correct Answer: Analysis of variance (ANOVA)

Explanation:

Data collected in research studies fall into one of two categories—continuous or discrete. Continuous data can be displayed on a curve. Examples include height, weight, and time recorded in a 40-yard dash. Discrete data represent data that fall into specific categories such as gender or the presence or absence of a risk factor. ANOVA is used to determine statistical significance in mean values of continuous data when there are more than two independent samples. The 2-sample
t
test compares mean values of continuous data between two independent groups. The Chi-square test and Fisher's exact tests are tests used to analyze discrete data.

Question 83:

An 11-year-old child has Ewing’s sarcoma of the femoral diaphysis with a small soft-tissue mass. Staging studies show no evidence of metastases. Treatment should consist of

Options:

chemotherapy and radiation therapy to the femur.
chemotherapy and wide resection.
chemotherapy and above-knee amputation.
hip disarticulation.
wide resection.

Correct Answer: chemotherapy and wide resection.

Explanation:

Question 84:

Options:

No further treatment
Closed reduction under conscious sedation
Closed reduction under general anesthesia in the operating room with neurologic monitoring
Occipitocervical fusion
Posterior atlantoaxial fusion

Correct Answer: No further treatment

Explanation:

The clinical presentation is consistent with chronic torticollis caused by Atlantoaxial rotatory displacement (AARD). Because both halter traction and halo traction were attempted and failed, the next most appropriate next step in management is posterior atlantoaxial fusion.
Common causes of Atlantoaxial rotatory displacement (AARD) include infection, trauma, and recent neck surgery. Diagnosis is challenging and is best confirmed with dynamic CT (CT with the head turned maximally to either side and at neutral). If the symptoms are acute (less than 7 days) then initial treatment with a soft collar and anti-inflammatory medications is indicated. If the condition has been present for more than a week, more aggressive treatment with halter traction (present 1 week to 1 month) or halo traction (present for 1-3 months) is indicated. If nonoperative modalities fail, the condition has been present for > 3 months, or the patient has neurologic deficits, then posterior C1-C2 fusion is indicated.
Copley et al discuss the evaluation and treatment of various congenital and traumatic conditions of the pediatric cervical spine. They report that the underlying mechanism of Atlantoaxial rotatory displacement (AARD) is inflammation and spasm which can be caused by infection, prior surgery, trauma, and rheumatoid arthritis.
Subach et al reviewed at 20 children with atlantoaxial rotatory subluxation. They found that of the 20 patients treated overall, conservative management failed in 6 (30%), and they required posterior fusion because of recurrence of the atlantoaxial rotatory subluxation or unsuccessful reduction. The major factor predicting the failure of conservative management was the duration of subluxation before initial reduction. Patients with long-standing subluxation were more likely to experience recurrence and require surgery.
Figure A shows an asymmetric placed odontoid within the ring of C1. There is an increased distance from the odontoid to the right arch of C1 which is fixed and minimally changes with maximal rotation to the left. This radiographic finding is indicative of fixed subluxation. Illustration A further demonstrates this.
Incorrect
(SBQ12SP.1) A 65-year-old female with a history of breast cancer presents with bilateral buttock and leg pain that is worse with walking and improves with sitting. In addition, she reports that she feels unsteady on her feet and requires holding the railing when going up and down stairs. On physical exam she is unable to complete a tandem gait and has hip flexion weakness, ankle dorsiflexion weakness, and ankle plantar flexion weakness. Her reflex exam shows 3+ bilateral patellar reflexes. Radiographs and an MRI are shown in Figure A and B. What is the next most appropriate step in management.
Review
Topic
Lumbar epidural injection
Physical therapy with core strengthening and anti-inflammatory medications as needed
Lumbar decompression
Lumbar decompression and fusion
MRI of the cervical and thoracic spine
The clinical scenario is consistent with a patient with symptoms of degenerative spondylolisthesis AND symptoms of myelopathy. Myelopathy must be ruled out by performing an MRI of the cervical and thoracic spine.
Tandem stenosis occurs in approximately 5 to 25% of patients. Because of the stepwise progressive nature of myelopathy, treatment of myelopathy often takes precedence over lumbar spinal stenosis.
Rhee et al. found that the sensitivity and specificity of specific physical exam findings varies. Both the upward babinski reflex and the presence of clonus were found to be very non-sensitive (13%). The most sensitive provacative test was found to be the Hoffman sign (59%).
Salvi et al. reviewed the classic presentations for cervical myelopathy including demographics, history, and physical exam findings (the inability to preform a tandem gait, hyperreflexia, an abnormal babinksi and hoffman reflex, the inability to preform rapid movements and bilateral muscle weakness). Additionally they identify other potential causes for myelopathy, including multiple sclerosis, amyotrophic lateral sclerosis, multifocal motor neuropathy, and Guillain-Barre´syndrome.
Maezawa et al. showed that gait analysis can identify a pattern in patients with myelopathy. Patients with severe myelopathy have a characteristic gait with hyperextension of the knee in the stance phase without plantar flexion of the ankle in the swing phase. They also have decreased walking speed and stride length with a prolonged stance phase.
Figure A and B show a classic degenerative spondylolisthesis.
Incorrect Answers:

Question 85:

Options:

Varus malreduction of the talar neck
Osteonecrosis of the talar body
Subtalar traumatic arthropathy
Nonunion of the talar neck
Occult infection

Correct Answer: Osteonecrosis of the talar body

Explanation:

Question 86:

Options:

Reposition the harness to hold the hips in 70 degrees of abduction
Closed reduction and arthrography under anesthesia
Open reduction and a spica cast
Continued harness treatment in the current position
Spica cast

Correct Answer: Continued harness treatment in the current position

Explanation:

DISCUSSION: The infant has a well-positioned hip in the Pavlik harness and treatment should be continued in the current position. The success rate is over 90% with the use of this device for a dislocatable hip. Ultrasound is a useful tool to confirm appropriate positioning of the cartilaginous femoral head during treatment. If the femoral head is not reduced after 2 to
3 weeks in the harness, this mode of treatment should be abandoned. Forceful extreme abduction can cause osteonecrosis of the femoral epiphysis and should be avoided. Closed reduction, arthrography, and spica casting are indicated if the hip cannot be maintained in a reduced position with the harness.
REFERENCES: Lehmann HP, Hinton R, Morello P, et al: Developmental dysplasia of the hip practice guideline: Technical report. Committee on Quality Improvement, and Subcommittee on Developmental Dysplasia of the Hip. Pediatrics 2000;105:E57.
Haynes RJ: Developmental dysplasia of the hip: Etiology, pathogenesis, and examination and physical findings in the newborn. Instr Course Lect 2001;50:535-540.

Question 87:

The teardrop shape marked with an asterisk in Figure 61 represents what anatomic structure?

Options:

Anterior superior iliac spine
Sciatic buttress
A column of bone running from the anterior inferior iliac spine (AIIS) to the posterior superior iliac spine (PSIS)
The most superior portion of the roof of the acetabulum
Iliopectineal line

Correct Answer: A column of bone running from the anterior inferior iliac spine (AIIS) to the posterior superior iliac spine (PSIS)

Explanation:

DISCUSSION: The teardrop can be visualized on the obturator outlet view of the pelvis and represents a thick column of bone that runs from the AIIS to the PSIS. Half pins for eternal fixation frames or screws can be inserted into this column for fixation of fractures.
REFERENCES: Gardner MJ, Nork SE: Stabilization of unstable pelvic fractures with supra-acetabular compression external fixation. J Orthop Trauma 2007;21:269-273.
Haidukewych GJ, Kumar S, Prpa B: Placement of half-pins for supra-acetabular external fixation: An anatomic study. Clin Orthop Relat Res 2003;411:269-273.
Kim WY, Hearn TC, Seleem O, et al: Effect of pin location on stability of pelvic external fixation. Clin Orthop Relat Res 1999;361:237-244.

Question 88:

Options:

Distal metatarsal osteotomy
Distal soft-tissue reconstruction
Proximal metatarsal osteotomy
Lapidus bunionectomy

Correct Answer: Distal metatarsal osteotomy

Explanation:

DISCUSSION
Patients with painful progressive hallux valgus are surgical candidates. Presurgical evaluation includes radiographic examination. The IMA between the first and second metatarsals as well as the HVA must be measured. If the IMA is smaller than 15 degrees and the HVA is smaller than 35 degrees, a distal osteotomy is preferred. Distal soft-tissue reconstruction is only useful for IMAs smaller than 11 degrees and HVAs smaller than 25 degrees. Proximal osteotomies and the Lapidus bunionectomy are reserved for larger hallux valgus deformities with IMAs exceeding 15 degrees and HVAs exceeding 35 degrees.
RECOMMENDED READINGS
Pentikainen I, Ojala R, Ohtonen P, Piippo J, Leppilahti J. Distal Chevron Osteotomy: Preoperative Radiological Factors Contributing to Long-Term Radiological Recurrence of Hallux
Valgus. Foot Ankle Int. 2014 Sep 5. pii: 1071100714548703. [Epub ahead of print] PubMed PMID: 25192724.
View Abstract at PubMed
Fakoor M, Sarafan N, Mohammadhoseini P, Khorami M, Arti H, Mosavi S, Aghaeeaghdam A. Comparison of Clinical Outcomes of Scarf and Chevron Osteotomies and the McBride Procedure in the Treatment of Hallux Valgus Deformity. Arch Bone Jt Surg. 2014 Mar;2(1):31-

Question 89:

Options:

No range-of-motion exercises until 6 weeks postoperative
Begin immediate strengthening
Avoid valgus stress to elbow
Avoid shoulder abduction The MRI scan shows injuries to both the medial and lateral ligamentous structures of the elbow, with significant widening of the radiocapitellar joint space. The patient’s ongoing symptoms are consistent with posterolateral rotatory instability related to lateral collateral ligament insufficiency. After surgical repair versus reconstruction of the lateral collateral ligament, it is important to avoid varus stress to the elbow, which can result in failure or loosening of the lateral structures. During shoulder abduction, gravity applies a varus stress to the elbow, and it should be avoided. Limiting range of motion for the first 6 weeks would result in significant elbow stiffness. Valgus stress should be avoided in the setting of a medial collateral ligament repair or reconstruction. Strengthening is usually delayed until appropriate soft-tissue healing has been achieved.

Correct Answer: Avoid shoulder abduction The MRI scan shows injuries to both the medial and lateral ligamentous structures of the elbow, with significant widening of the radiocapitellar joint space. The patient’s ongoing symptoms are consistent with posterolateral rotatory instability related to lateral collateral ligament insufficiency. After surgical repair versus reconstruction of the lateral collateral ligament, it is important to avoid varus stress to the elbow, which can result in failure or loosening of the lateral structures. During shoulder abduction, gravity applies a varus stress to the elbow, and it should be avoided. Limiting range of motion for the first 6 weeks would result in significant elbow stiffness. Valgus stress should be avoided in the setting of a medial collateral ligament repair or reconstruction. Strengthening is usually delayed until appropriate soft-tissue healing has been achieved.

Explanation:

When performing reverse shoulder arthroplasty, what factor leads to an increase in the complication indicated by the black arrow in Figure 1?

Question 90:

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

Options:

reduction of the serum alkaline phosphatase level by 50%.
preoperative radiation therapy of 600 cGy to the surgical site.
aspiration of the knee joint with cell count.
insertion of a vena caval filter.
administration of 25 mg of indomethacin three times a day.

Correct Answer: reduction of the serum alkaline phosphatase level by 50%.

Explanation:

Question 91:

-What is the most appropriate initial treatment for her condition?

Options:

Complete rest and a slow return to sports
Physical therapy
Corticosteroid injection
Arthroscopic surgery PREFERRED RESPONSE: 2 Question 75-After 1 year of following recommended treatment, this patient continues to experience her symptoms and has had to cease all sports activity. An MRI scan reveals no evidence of definitive labral or rotator cuff pathology. At this stage, what is the most appropriate treatment option?
Arthroscopic rotator cuff repair
Arthroscopic biceps tenodesis
Arthroscopic capsular plication
Arthroscopic superior labral anterior-posterior repair

Correct Answer: Corticosteroid injection

Explanation:

DISCUSSION FOR QUESTIONS 73 THROUGH 75
This patient has a history most consistent with multidirectional instability. A lax capsule causes subluxation of the shoulder and strain on the rotator cuff and may result in pain and instability. The capsule is most closely associated with the cause of her problem. Initial treatment for multidirectional instability is physical therapy focusing on restoring balance to the shoulder with rotator cuff and scapular stabilization exercises. Nonsurgical therapy should be protracted and is the mainstay of treatment in this scenario. This patient has exhausted all nonsurgical measures and is now a candidate for surgical reconstruction. Capsular plication will best address the lax capsule and provide the best option for reducing her symptoms. The rotator cuff and biceps tendon may be secondarily strained but are not the primary sources of the problem. The brachial plexus does not address the etiology, but rather the symptoms that may occur as a result of instability of the shoulder joint.
Complete rest will not alleviate the patient's underlying condition because the shoulder girdle may still be weak and symptoms likely will return. A corticosteroid injection and arthroscopic surgery are too invasive as initial treatment for this condition. Arthroscopic rotator cuff repair, a biceps tenodesis, and superior labral anterior-posterior repair are unlikely to result in symptomatic improvement for this patient and are not associated with pathologic findings in the setting of multidirectional instability.

Question 92:

Options:

hip flexion, knee extension
hip extension, knee extension
hip flexion, knee flexion
hip extension, knee flexion
the pressure does not vary based on position

Correct Answer: hip flexion, knee extension

Explanation:

Question 93:

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Options:

Medial
Lateral
Posterior
Proximal

Correct Answer: Medial

Explanation:

Question 94:

Options:

- Subtalar arthritis
- Osteonecrosis
- Nonunion
- Varus malunion

Correct Answer: - Subtalar arthritis

Explanation:

DISCUSSION
When a displaced talar neck fracture occurs, the rate of osteonecrosis is high; however, many revascularize the talus without collapse. A nonunion can occur but is less common than osteonecrosis and arthritis. A varus malunion can be debilitating and lead to subtalar arthritis. In a fracture with the talar body dislocated posteromedially (such as in this example) neurologic deficits in the tibial nerve distribution are common but typically improve with urgent
reduction. Studies show that posttraumatic subtalar arthritis is common after this injury and is the most likely cause of long-term functional impairment.
RECOMMENDED READINGS
Vallier HA, Nork SE, Barei DP, Benirschke SK, Sangeorzan BJ. Talar neck fractures: results and outcomes. J Bone Joint Surg Am. 2004 Aug;86-A(8):1616-24. PubMed PMID: 15292407.
View Abstract at PubMed
Lindvall E, Haidukewych G, DiPasquale T, Herscovici D Jr, Sanders R. Open reduction and stable fixation of isolated, displaced talar neck and body fractures. J Bone Joint Surg Am. 2004 Oct;86-A(10):2229-34. PubMed PMID: 15466732.
View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 10 THROUGH 12
10A
10B
10C
Figure 10a is the radiograph of a 30-year-old man who sustained an injury in a motor vehicle collision.

Question 95:

Options:

CT-guided closed biopsy.
open surgical biopsy.
antibiotic coverage for Staphylococcus aureus.
broad-spectrum antibiotic coverage.
a follow-up MRI scan in 8 weeks.

Correct Answer: CT-guided closed biopsy.

Explanation:

Question 96:

Options:

Shortening of 3 cm
Severity of trauma
Duration of immobilization
Type of immobilization
Closed reduction

Correct Answer: Severity of trauma

Explanation:

Question 97:

Options:

Triple arthrodesis
Soft-tissue releases as necessary
Tendon transfers to balance the feet in a neutral plantigrade position
Physical therapy for range of motion and stretching
Botulinum injections followed by serial casting

Correct Answer: Soft-tissue releases as necessary

Explanation:

Question 98:

Options:

Thumb extension
Forearm supination
Finger extension
Forearm pronation

Correct Answer: Forearm supination

Explanation:

EXPLANATION:
The typical upper extremity deformity in spastic hemiplegic cerebral palsy consists of shoulder internal rotation, elbow flexion, forearm pronation and wrist flexion, and ulnar deviation. The pronation position of the forearm can make bimanual activities more challenging for the child. The wrist flexion and ulnar deviation deformity interferes with finger function and therefore with grasp and release patterns. By transferring the FCU tendon to the ECRB, the deforming force is released, and central wrist extension is augmented. This transfer can lead to a supination moment when it is routed around the ulna to the ECRB insertion on the dorsum of the wrist. Thumb and finger extension are not affected by an FCU-to-ECRB
tendon transfer. Forearm supination, not pronation, is potentially improved with this tendon transfer.

Question 99:

Options:

Measurement of volar compartment pressures and, if elevated, a bolus transfusion of 4 unit/kg of factor VIII concentrate, followed by continuous transfusion of factor VIII
Splinting of the extremity with the elbow flexed and the wrist in extension, elevation of the extremity, observation, and if no improvement, continuous transfusion of factor VIII (4 unit/kg)
A bolus transfusion of 4 unit/kg of factor VIII concentrate, followed by continuous transfusion of factor VIII, measurement of forearm compartment pressures, splinting of the extremity with the elbow and wrist flexed, and surgical release of the volar forearm compartments if pressures are elevated
A bolus transfusion of 4 unit/kg of factor VIII concentrate, followed by continuous transfusion of factor VIII and an emergency fasciotomy
A bolus transfusion of 4 unit/kg of factor VIII concentrate, laboratory studies consisting of serum electrolytes and creatine phosphokinase levels, IV injections of bicarbonate to alkalize the urine, and renal dialysis

Correct Answer: A bolus transfusion of 4 unit/kg of factor VIII concentrate, followed by continuous transfusion of factor VIII, measurement of forearm compartment pressures, splinting of the extremity with the elbow and wrist flexed, and surgical release of the volar forearm compartments if pressures are elevated

Explanation:

Question 100:

Options:

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

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

Orthopedic Surgery Board Review MCQs: Arthroplasty, Ligament & Spine | Part 149

Orthopedic Board Review MCQs: Knee, Shoulder, Trauma & Infection | Part 159

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 159

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index