Orthopedic Board Review MCQs: Spine, Knee & Tendon | OITE

About This Board Review Set

This is Part 176 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

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

How to Use the Interactive Quiz

Two distinct learning modes are available:

Study Mode — After selecting an answer, you immediately see whether you are correct or incorrect, together with a full clinical explanation and literature references.
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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 176

This module focuses heavily on: Deformity, Knee, Spine, Tendon.

Sample Questions from This Set

Sample Question 1: A 21-year-old collegiate wrestler sustains a blow to his right eye during a match. Examination reveals anisocoria with a dilated right pupil. The globe is properly formed, and extra-occular movements and the visual field are grossly intact....

Sample Question 2: Flexion-distraction injuries of the thoracolumbar spine are most frequently associated with injury to what organ system?...

Sample Question 3: A 26-year-old man was thrown from a car and sustained the injury seen in Figures 44a and 44b. Nonsurgical management of this injury is recommended. Which of the following factors increases the risk of nonunion?...

Sample Question 4: During treatment of rupture of the subscapularis tendon with associated biceps instability, treatment of the biceps tendon should include which of the following?...

Sample Question 5: A 13-year-old girl is referred for a painful progressive valgus deformity of the right knee. Examination reveals an antalgic gait with an obvious valgus deformity. The right distal femur has a palpable, tender mass with erythema and warmth....

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 21-year-old collegiate wrestler sustains a blow to his right eye during a match. Examination reveals anisocoria with a dilated right pupil. The globe is properly formed, and extra-occular movements and the visual field are grossly intact. What is the most likely diagnosis?

Explanation

DISCUSSION: Traumatic mydriasis occurs from a contusion to the iris sphincter. This is a transient phenomenon during which the iris fails to constrict properly, resulting in a dilated pupil. More severe trauma can result in a tear of the sphincter and permanent pupillary deformity. In association with head injury, traumatic anisocoria would be a concerning indicator of the severity of injury. Retinal detachment, lens dislocation, corneal abrasion, and traumatic hyphema are all potential results of eye injury but are not reflected by this clinical description.
REFERENCES: Brucker AJ, Kozart DM, Nichols CW, Irving MR: Diagnosis and management of injuries to the eye and orbit, in Torg JS (ed): Athletic Injuries to the Head, Neck, and Face, ed 2. St Louis, MO, Mosby Year Book, 1991, pp 650-670.
Orlando RG, Doty JH: Ocular sports trauma: A private practice study. J Am Optom Assoc 1996;67:77-80.

Question 2

Flexion-distraction injuries of the thoracolumbar spine are most frequently associated with injury to what organ system?

Explanation

DISCUSSION: In patients with flexion-distraction injuries of the thoracolumbar spine, 50% have associated, potentially life-threatening, visceral injuries that occasionally are diagnosed hours or even days after admission. Based on these findings, consultation with a general surgeon is recommended. Blunt and penetrating injuries to the cardiopulmonary system or aorta sometimes can be seen with this type of injury, but they are no more common than with other types of thoracolumbar fractures because of the relatively mild bony injury anteriorly. Neurologic trauma with this type of fracture is also somewhat rare.
REFERENCES: Levine AM (ed): Orthopaedic Knowledge Update: Trauma. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 351-360.
Inaba K, Kirkpatrick AW, Finkelstein J, et al: Blunt abdominal aortic trauma in association with thoracolumbar spine fractures. Injury 2001;32:201-207.

Question 3

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

Explanation

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

2 cm predispose to nonunion. Arch Orthop Trauma Surg 2001;121:207-211.
Robinson CM, Court-Brown CM, McQueen MM, et al: Estimating the risk of nonunion following nonoperative treatment of a clavicular fracture. J Bone Joint Surg Am

2004;86:1359-1365.

Question 4

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 5

A 13-year-old girl is referred for a painful progressive valgus deformity of the right knee. Examination reveals an antalgic gait with an obvious valgus deformity. The right distal femur has a palpable, tender mass with erythema and warmth. Figures 4a and 4b show a clinical photograph and a radiograph. Management should consist of

Explanation

DISCUSSION: The radiograph shows a pathologic fracture through a destructive lesion of the distal femur metaphysis with osteolytic and osteoblastic features. The lateral cortex is destroyed, and there is periosteal new bone formation. These findings are consistent with malignancy, most likely an osteogenic sarcoma. Patients with suspected malignant tumors are best managed by surgeons with specific expertise in orthopaedic oncology. The biopsy of a malignant lesion should be deferred to the surgeon who is capable of definitive management of the patient.
REFERENCES: Enneking W: Principles of musculoskeletal oncologic surgery, in Evarts C (ed): Surgery of the Musculoskeletal System. New York, NY, Churchill Livingston, 1990.
Herring JA: General principles of tumor management, in Herring JA (ed): Tachdjian’s Pediatric Orthopaedics, from the Texas Scottish Rite Hospital for Children, ed 3. Philadelphia, PA, WB Saunders, 2002, pp 1897-1900.

Question 6

Figure 14 shows the clinical photographs and radiograph of an 8-year-old girl who has a progressive equinus deformity of the right ankle. There is no history of trauma or infection. What is the most likely diagnosis?

Explanation

DISCUSSION: Focal scleroderma is characterized by the formation of patches of sclerotic skin, also known as morphea, or streaks of sclerosis (linear scleroderma). Systemic involvement in focal scleroderma is unusual; however, progression during childhood is common. Contracture of underlying tissues is common, often resulting in serious joint contractures. Bony changes similar to those seen in melorheostosis can be seen. This patient has characteristic skin changes, atrophy of the soft tissues, Achilles tendon contractures, and calcaneal deformities. There are no signs of arthrogryposis, which usually presents with bilateral congenital deformities, including equinovarus. Klippel-Trenaunay-Weber syndrome is characterized by venous malformation in association with focal overgrowth.
REFERENCE: Bottoni CR, Reinker KA, Gardner RD, Person DA: Scleroderma in childhood: A 35-year history of cases and review of the literature. J Pediatr Orthop 2000;20:442-449.

Question 7

What nerve is most at risk during placement of the anterolateral portal in elbow arthroscopy?

Explanation

DISCUSSION: The radial nerve is only 4 mm from the anterolateral portal, while the median nerve is 11 mm away from the anteromedial portal. The ulnar nerve is only at risk on the medial side of the elbow. Anterior and posterior interosseous nerves are more distal within the forearm and are not in danger during portal placement.
REFERENCES: O’Driscoll SW, Morrey BF: Elbow arthroscopy, in Morrey BF (ed): The Elbow. Philadelphia, PA, Lippincott, Williams and Wilkins, 1994, pp 21-34.
Field LD, Altchek DW, Warren RF, O’Brien SJ, Skyhar MJ, Wickiewicz TL: Arthroscopic anatomy of the lateral elbow: A comparison of three portals. Arthroscopy 1994;10:602-607.

Question 8

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 9

Figures 38a and 38b

Explanation

DISCUSSION
Inversion of the ankle can cause various injuries about the foot and ankle, all via the same mechanism. Fifth metatarsal base avulsion (Figure 35) fractures can be treated with use of a walking boot until pain subsides. Jones fractures (Figure 36) can be treated with surgical or nonsurgical treatment, although young, active patients are perhaps better treated with ORIF, which can decrease disability time. Treatment of an anterior process calcaneus fracture (Figure 37) is similar to that for a fifth metatarsal base avulsion fracture. Figures 38a and 38b show a calcaneal fracture-dislocation, which necessitates ORIF.
RECOMMENDED READINGS
Schepers T, Backes M, Schep NW, Carel Goslings J, Luitse JS. Functional outcome following a locked fracture-dislocation of the calcaneus. Int Orthop. 2013 Sep;37(9):1833-8. PubMed PMID: 23959223. View Abstract at PubMed
Polzer H, Polzer S, Mutschler W, Prall WC. Acute fractures to the proximal fifth metatarsal bone: development of classification and treatment recommendations based on the current evidence. Injury. 2012 Oct;43(10):1626-32. doi: 10.1016/j.injury.2012.03.010. Epub 2012 Mar 30. Review. PubMed PMID: 22465516. View Abstract at PubMed
Roche AJ, Calder JD. Treatment and return to sport following a Jones fracture of the fifth metatarsal: a systematic review. Knee Surg Sports Traumatol Arthrosc. 2013 Jun;21(6):1307-15. doi: 10.1007/s00167-012-2138-8. Epub 2012 Sep 6. Review. PubMed PMID: 22956165. View Abstract at PubMed
Berkowitz MJ, Kim DH. Process and tubercle fractures of the hindfoot. J Am Acad Orthop Surg. 2005 Dec;13(8):492-502. Review. PubMed PMID: 16330511. View Abstract at PubMed

Question 10

Figure 48 shows an MRI scan of the knee. The arrow is pointing to what structure?

Explanation

DISCUSSION: The arrow points to the biceps femoris, which is inserted onto the fibula. The biceps femoris lies at the posterolateral aspect of the thigh. The semimembranosus and the semitendinous lie at the posterior medial aspect of the thigh.
REFERENCES: Gray H: Anatomy of the Human Body. Philadelphia, PA, Lea and Febiger, 1918, 2000.
Netter FH: Atlas of Human Anatomy. Summit, NJ, Ciba-Geigy, 1989, pp 464-465.

Question 11

Which modality has the broadest application for the reduction of postsurgical transfusion?

Explanation

DISCUSSION:
TXA is easy to administer, inexpensive, and safe for virtually all patients. Multiple studies have demonstrated transfusion rates lower than 3% for total knee arthroplasty and lower than 10% for total hip arthroplasty. Regional and hypotensive anesthesia effectively reduce transfusion; however, they cannot be used in as wide a range of patients as can TXA. A reduced transfusion trigger must be considered along with patient symptoms when determining the need for transfusion.

Question 12

A 40-year-old man with a history of Legg-Calve-Perthes disease underwent a right hip resurfacing 3 years ago with no perioperative complications. Hip pain has developed gradually during the last 4 months. Radiographs show no evidence of fixation loosening or any adverse changes at the femoral neck. No periarticular osteolysis is evident. What is the most appropriate management of this condition?

Explanation

DISCUSSION:
Controversy persists over what exactly is the best approach to managing patients with metal-on-metal (MOM) hip arthroplasties. All patients with painful MOM hip arthroplasties should be examined for fixation loosening, wear/osteolysis, and infection—no differently than patients without MOM hip arthroplasties. It is recommended to obtain serum trace element levels. If the levels are high, cross- sectional imaging should be obtained to determine whether any pseudotumor or tissue necrosis is present around the hip arthroplasty. Hip aspiration should be considered if concern for infection exists. Adverse tissue reaction has been identified to occur around MOM hip arthroplasties. The predominant histologic feature is tissue necrosis with infiltration of lymphocytes and plasma cells.

Question 13

A 28-year-old man sustained a fracture-dislocation of T8 in a motor vehicle accident 1 week ago. The injury resulted in complete paraplegia. Management should consist of

Explanation

DISCUSSION: With a complete injury in the thoracic spinal cord, the likelihood of neurologic recovery is small. If possible, treatment should be planned to allow rapid mobilization and rehabilitation without the use of braces and their associated skin problems. The use of long segment fixation provides for rapid mobilization without having to use braces postoperatively. The use of steroid protocol is controversial and should be considered only if it can be started within 8 hours of the injury. Laminectomy is contraindicated because it will increase instability.
REFERENCE: Tasdemiroglu E, Tibbs PA: Long-term follow-up results of thoracolumbar fractures after posterior instrumentation. Spine 1995;20:1704-1708.

Question 14

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

Explanation

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

Question 15

-The center of rotation of the knee can be best described as

Explanation

Question 16

What is the most likely contributory factor to this patient's problem?

Explanation

DISCUSSION
Proximal humeral epiphysiolysis (little leaguer’s shoulder) is an overuse condition of the proximal humeral physis. Patients report diffuse pain that is worse with throwing. Little leaguer’s shoulder is caused by rotational stress placed on the proximal humeral epiphysis during overhead throwing. The growth plate is weakest to torsion stress and is most susceptible to injury during periods of rapid growth commonly seen during puberty. Most chronic shoulder injuries occur in throwing athletes between 13 and 16 years of age. Factors that contribute to the condition include excessive throwing, improper throwing mechanics, and muscle-tendon imbalance. Radiographic findings typically are normal but may indicate subtle widening of the proximal humeral physis, and, in more severe cases, metaphyseal demineralization or fragmentation. Surgical fixation is not required for healing. An initial 3-month period of rest and activity modification will typically result in resolution of symptoms. Nonsteroidal anti-inflammatory drugs may be used as needed. After the rest period, a gradual return to throwing is implemented until the patient’s condition returns to baseline. This protocol has a long-term success rate exceeding 90%. Pitching coaches should evaluate throwing mechanics and maintain pitch counts. The most common cause of this condition is overuse, as is seen in pitchers who throw all year. Internal rotation deficit and internal impingement is typically a finding in older athletes without open physes. This patient had no evidence of rotation deficit upon examination, making this diagnosis unlikely.

Question 17

A 22-year-old wrestler who underwent an open anterior shoulder reconstruction to repair a dislocated shoulder 6 months ago now reports shoulder pain after attempting a takedown. Examination reveals external rotation that is 15 degrees greater than the contralateral side. He has pain associated with abduction and external rotation but no apprehension. Which of the following tests would most likely reveal positive findings?

Explanation

DISCUSSION: Postoperative subscapularis detachment can be identified with a positive lift-off test that reveals weakness in internal rotation. This complication does not necessarily compromise the anterior capsule repair. The load-and-sift maneuver and articular contrast studies may be normal. Supraspinatus tests for impingement and weakness should be negative.
REFERENCES: Gerber C, Krushell RJ: Isolated ruptures of the tendon of the subscapularis muscle: Clinical fractures in 16 cases. J Bone Joint Surg Br 1991;73:389-394.
Hawkins RJ, Bokor DJ: Clinical evaluation of the shoulder, in Rockwood CA, Matsen FA III (eds): The Shoulder. Philadelphia, PA, WB Saunders, 1990, pp 149-177.

Question 18

Figure 1 is the radiograph of a 22-year-old man who underwent an open reduction and pinning of a perilunate dislocation 10 weeks ago. The hardware has been removed. What is the best next step?

Explanation

EXPLANATION:
Lunate or perilunate dislocations are usually treated with open reduction and internal fixation through a dorsal or combined dorsal and volar approach. A high index of suspicion is necessary when treating patients who sustain multiple trauma because as many as 25% of lunate or perilunate dislocations are missed initially. The radio dense appearance of the lunate seen in Figure 1 is an example of transient ischemia of the lunate that can occur following treatment of lunate and perilunate dislocations. It has been reported in up to 12.5% of cases. This usually is seen between 1 and 4 months post injury with a relative radio density of the lunate. This appearance of the lunate should not be over treated and usually is a benign self-limiting event. Surgery is not indicated at this time; the incorrect responses are treatment options for Kienbock disease. Treatment of the lunate or perilunate dislocation involves initial gentle closed reduction followed by open reduction, ligamentous and bone repair, and internal fixation. Median nerve dysfunction is common, and a simultaneous carpal tunnel release is often performed. Early treatment seems to produce better results, but good results have been reported when treatment is delayed for up to 6 months. The many questions regarding treatment of this problem involve the use of capsulodesis to supplement intercarpal ligament repair, repair/stabilization of the lunotriquetral interval vs no treatment of that articulation, and intercarpal fixation techniques. In delayed cases, proximal row carpectomy when the head of the capitate is intact and total wrist fusion if there are degenerative changes have been used. Chondral injuries are common, may not be recognized on radiographs, and may negatively affect longterm outcomes. Even when treatment is optimal, this injury is associated with a guarded prognosis and possible permanent partial loss of wrist motion and grip strength. At 10-year follow-up, radiographs will often demonstrate degenerative changes, but these changes do not always substantially negatively affect hand function.

Question 19

Figure 1 shows the radiograph and Figure 2 shows the MRI scan obtained from a 37-year-old woman with a month history of left hip pain. Which combination of a single symptom and examination finding is most likely in this scenario?

Explanation

MRI reveals an anterior labral tear, and the radiograph shows minimal arthritis with possible dysplasia. The most common location of pain in patients with a labral tear is the groin, and the most common physical finding is a positive impingement test result. Pain during sitting, clicking, and buttock pain are frequently described by patients with a labral tear, but these symptoms are less common than groin pain. A positive posterior impingement test finding is more common in patients with a posterior labral tear. Although age over 40 years and a body mass index higher than 30 can adversely affect clinical outcomes after joint preservation procedures such as PAO, hip arthroscopy, and femoral acetabular impingement surgery, the presence of hip arthritis on presurgical radiographs is the most commonly mentioned cause of failed hip joint preservation surgery. Tönnis grade is a radiographic measure of hip arthritis. A higher Outerbridge score is associated with more frequent poor outcomes after hip arthroscopy; however, the Outerbridge cartilage score is determined by direct visualization at the time of surgery. The Outerbridge score cannot be determined presurgically.

Question 20

A Trendelenburg gait is most likely to be seen in association with

Explanation

DISCUSSION: A Trendelenburg gait results from weakness of the gluteus medius, which is innervated by the L5 nerve root. A paracentral disk herniation at L4-L5 most commonly results in an L5 radiculopathy and thus weakness of the gluteus medius. A paracentral herniation at L5-S1 most commonly affects the S1 nerve root. A paracentral herniation at L3-L4, a central herniation at L3-L4, and a far lateral herniation at L4-L5 all affect the L4 root.
REFERENCES: Fardon DF, Garfin SR, Abitbol J, et al (eds): Orthopedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 323-332.
Andersson GB, Deyo RA: History and physical examination in patients with herniated lumbar discs. Spine 1996;21:10S-18S.

Question 21

A 23-year-old woman has had vague left knee pain for the past 6 months. A radiograph and CT scan are shown in Figures 50a and 50b. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographic appearance of the lesion emanating from the posterior cortex of the left distal femur is consistent with a surface bone-producing lesion; therefore, the most likely diagnosis is a parosteal osteosarcoma. In an osteochondroma, the cortex and medullary cavity of the lesion are in continuity with that of the native bone. A dedifferentiated chondrosarcoma has histologic components of a high-grade sarcoma plus a benign or low-grade malignant cartilage tumor. Tumoral calcinosis is characterized by amorphous calcium in the soft tissues and does not emanate from the bone itself. While often confused with parosteal osteosarcoma, myositis ossificans is usually more mature at the periphery of the lesion rather than the center. In addition, myositis ossificans does not involve the underlying cortex but remains separate from the bone.
REFERENCES: Unni KK: Dahlin’s Bone Tumors: General Aspects and Data on 11,087 Cases, ed 5. Philadelphia, PA, Lippincott-Raven, 1996, pp 185-196.
Okada K, Frassica FJ, Sim FH, Beabout JW, Bond JR, Unni KK: Parosteal osteosarcoma. A clinicopathological study. J Bone Joint Surg Am 1994;76:366-378.

Question 22

A 5-year-old boy has had midfoot pain with activity for the past 3 months. He has no pain at rest. Radiographs are shown in Figures 29a and 29b. Management should consist of

Explanation

DISCUSSION: The radiographs show classic findings for Koehler’s disease (osteochondrosis of the navicular). The patient’s age and clinical history are typical for this self-limiting condition. Patients will improve with time, but the duration of symptoms is much shorter if the patient is placed in a cast. There is no role for surgery in this disease.
REFERENCE: Williams GA, Cowell HR: Koehler’s disease of the tarsal navicular. Clin Orthop 1981;158:53-58.

Question 23

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? Review Topic

Explanation

The patient has chronic tibial osteomyelitis that is due to low virulent bacteria. The history and studies do not suggest the need for an amputation or a free-flap procedure. This is a localized tibial infection that is in a healed bone; there is no need to resect the entire area of the tibia bone around the infection. The most appropriate treatment is curettage, debridement of nonviable bone, and placement of absorbable antibiotic beads, followed by a course of IV antibiotics from 1 to 4 weeks and a 6-week course of oral antibiotics. Studies have shown that in cases of localized osteomyelitis that are of low virulence, as little as 1 week of IV antibiotics followed by 6 weeks of oral antibiotics is successful.

Question 24

In patients with Crowe types III and IV developmental dysplasia of the hip with high hip centers, acetabular reconstruction often requires lowering the acetabular component into the native acetabulum. In doing so, considerable risk for limb lengthening beyond 4 cm exists, making the hip difficult to reduce and raising the risk for nerve injury. Which technique is used to overcome this problem?

Explanation

DISCUSSION:
When substantial lengthening of a dysplastic hip will occur because a high dislocation is relocated into a considerably lower acetabulum, a femoral shortening may be necessary to reduce the hip and avoid a stretch injury to the sciatic nerve. No other choice specifically addresses the need for femoral shortening, and high offset stems and lateralized liners may exacerbate the problem if used alone and without femoral shortening.

Question 25

Following closed reduction for the injury shown in Figures 69a and 69b, treatment should consist of

Explanation

Repair or reconstruction of the medial collateral ligament-The mechanism of dislocation during a fall on the outstretched hand would involve the body rotating internally on the elbow, which experiences an external rotation/valgus moment as it flexes. Posterior dislocations should therefore be reduced in supination. If valgus stability in pronation is demonstrated, the AMCL can be assumed to be intact, and rehabilitation in a hinged cast-brace with the elbow in full pronation can be commenced immediately.
Repair or reconstruction of the medial and lateral collateral ligaments-Acute dislocations can be reduced in supination and tested for valgus stability in pronation. Treatment is determined by the stability following reduction. When there are fractures, the principle is to fix the bones so that the only limitation is the ligaments and then to repair them if the elbow is not stable enough to permit early motion.
Immobilization for 14 days-The longer the immobilization had been, the larger the flexion contracture (p less than 0.001) and the more severe the symptoms of pain were. The results indicate that early active motion is the key factor in rehabilitation of the elbow after a dislocation. Simple dislocation of the elbow in the adult. Results after
closed treatment. Immobilization for 25 days- See above.

Question 26

BMP is FDA approved for well-defined medical conditions in limited patient populations. In which of the following clinical scenarios is use of rhBMP-2 FDA approved?

Explanation

rhBMP-2 is FDA approved for use together with the lumbar tapered fusion device (LT Cage; Medtronic) in single-level ALIF from L2 to S1 levels in degenerative disc disease.
rhBMP-2 is also FDA approved for use in open tibial shaft fractures stabilized with an IM nail and treated within 14 days of initial injury. rhBMP-7 has received FDA humanitarian device exemption approval as an alternative to autograft in recalcitrant long bone nonunions where use of autograft is unfeasible and alternative treatments have failed. It is also approved as an alternative to autograft in compromised patients (with osteoporosis, smoking or diabetes) requiring revision posterolateral/intertransverse lumbar fusion for whom autologous bone and bone marrow harvest are not feasible or are not expected to promote fusion.
Epstein reviewed the indications for rhBMP-2 use and its off-label use. She found that
anterior cervical surgery with BMP2 led to dysphagia and airway complications. With posterior lumbar spine surgery, complications included vertebral osteolysis (bone resorption) and ectopic bone formation/heterotopic ossifications, which made revision surgery difficult.
Burkus et al. prospectively compared 46 patients undergoing single-level ALIF with BMP-2 vs with autograft in an industry sponsored study. They found that patients receiving BMP-2 had higher rates of fusion and improvement in pain and neurologic status at 12 and 24 months compared with autograft, and there were no adverse events. They recommend rhBMP-2 in ALIF procedures to eliminate pain and scarring from iliac crest bone harvest.
Illustration A shows the FDA approved combination of INFUSE (rhBMP-2) and LT-CAGE device.
Incorrect Answers:

Question 27

A 12-year-old girl has scoliosis at T5-T10 that measures 62°. A clinical photograph of the axilla is shown in Figure 56. Management should consist of

Explanation

DISCUSSION: Neurofibromatosis type 1 (NF-1) is an autosomal-dominant disorder affecting about 1 in 4,000 people. NF-1 causes tumors to grow along various types of nerves and affects the development of non-nervous tissues, such as bone and skin. The gene for NF-1 is located on the long arm of chromosome 17 and codes the protein neurofibromin. Research indicates that NF-1 acts as a tumor-suppressor gene and, as such, plays an important role in the control of cell growth and differentiation. Axillary and inguinal freckling is considered a good diagnostic marker for NF-1. The hyperpigmented spots that measure from 2 mm to 4 mm may be congenital, but these typically appear and increase later in life. Scoliosis is the most common musculoskeletal disorder of NF-1. The curves are frequently dystrophic, kyphotic, and have a high risk of pseudarthrosis following spinal fusion. Anterior and posterior spinal fusion with rigid posterior segmental instrumentation is the treatment of choice.
REFERENCES: Goldberg Y, Dibbern K, Klein J, Riccardi VM, Graham JM Jr: Neurofibromatosis type 1: An update and review for the primary pediatrician. Clin Pediatr 1996;35:545-561.
Kim HW, Weinstein SL: Spine update: The management of scoliosis in neurofibromatosis. Spine 1997;22:2770-2776.

Question 28

Compared with percutaneous pinning with Kirschner wires (K-wires), the treatment of metacarpal neck fractures with cannulated intramedullary screws is associated with

Explanation

EXPLANATION:
In a biomechanical study, headless compression screws showed superior load to failure, higher three-point bending strength, and greater strength in axial loading compared with percutaneous K-wire fixation for metacarpal neck fractures. Headless compression screws provide greater initial stability to allow earlier motion in the postoperative period. No data comparing infection rates between the two methods of fixation are available; however, it is assumed that K-wires placed outside of the skin would have increased rates of infection. Neither fixation method would increase the time to healing.

Question 29

A 4-month-old infant is referred for evaluation of congenital scoliosis. The child has no congenital heart anomalies, and a renal ultrasound shows that he has one kidney. Examination reveals mild scoliosis and a large hairy patch on the child’s back. Neurologic evaluation is normal for his age. A clinical photograph and radiograph are shown in Figures 19a and 19b. Initial management should consist of

Explanation

DISCUSSION: Congenital anomalies of the spine, including failure of formation and failure of segmentation, are associated with other anomalies in other organ systems that develop at the same time. These include anomalies in the genitourinary system, cardiac anomalies, Sprengel’s deformity, radial hypoplasia, and gastrointestinal anomalies including imperforate anus and trachealesophageal fistula. Spinal dysraphism is the most common associated abnormality. McMaster found an 18% incidence before the common use of MRI. Bradford and associates reported on 16 of 42 patients with congenital spinal anomalies and spinal dysraphism using MRI. Neural axis lesions may be associated with visible midline abnormalities such as a hairy patch or nevus. The child has already had a cardiac and renal work-up, and based on the findings of the hairy patch and congenital vertebral anomalies, MRI of the entire spine is prudent at this time. Spinal fusion is indicated for progressive congenital scoliosis or kyphosis. Physical therapy does not affect the natural history of congenital scoliosis.
REFERENCES: McMaster MJ: Occult intraspinal anomalies and congenital scoliosis. J Bone Joint Surg Am 1984;66:588-601.
Bradford DS, Heithoff KB, Cohen M: Intraspinal abnormalities and congenital spine deformities: A radiographic and MRI study. J Pediatr Orthop 1991;11:36-41.
McMaster MJ, David CV: Hemivertebrae as a cause of scoliosis: A study of 104 patients.

J Bone Joint Surg Br 1986;68:588-595.

Question 30

A research study is initiated on 500 patients undergoing total hip arthroplasty. The patients are followed and outcome is assessed according to body mass index (BMI). The effects of BMI on outcome should be reported as which of the following?

Explanation

The study describes an example of a cohort study. Cohort studies follow a group of individuals over time and are optimal for studying the incidence, course, and risk factors of a disease. The effects in a cohort study are frequently reported in terms of relative risk (RR). Odds ratios are used to report effects in a case-control study. Incidence and prevalence rates are descriptors of a given characteristic either developed over time (incidence) or at one given time (prevalence). Confidence intervals are used to convey the significance of findings and are often used in lieu of or in conjunction with P values.

Question 31

A 19-year-old woman has had a painful prominence on the lateral border of her fifth metatarsal head since she was a young girl. Nonsurgical management, including the use of a wide toe box shoe, has failed to provide relief. Examination reveals a callus over the lateral prominence and on the plantar portion as well. A clinical photograph and a radiograph are shown in Figures 34a and 34b. Treatment should consist of

Explanation

DISCUSSION: The type of deformity described is a type 2 bunionette. There is often a congenital component to this deformity. The bowing of the fifth shaft differentiates a large intermetatarsal angle from a type 3 deformity. A distal chevron osteotomy corrects 1 degree in the intermetatarsal angle for every 1-mm shift. Because of limitations in the width of the fifth metatarsal neck, the allowable shift is generally 3 to 4 mm. This shift will not compensate for the large intermetatarsal angle. The floating osteotomy has a high rate of delayed union/nonunion and a low satisfaction rate. Metatarsal head excision has a high complication rate, including severe shortening, transfer metatarsalgia, stiffness, and pain. A more proximal procedure is necessary to correct the large intermetatarsal angle and the lateral bowing. The osteotomy of choice is a diaphyseal shaft osteotomy. Because this patient has a plantar callosity and a lateral callosity, the osteotomy is angled superiorly to elevate the fifth shaft with the shift, eliminating overload of the plantar metatarsal head and subsequent callus formation.
REFERENCES: Shereff MJ, Yang QM, Kummer FJ, Frey CC, Greenidge N: Vascular anatomy of the fifth metatarsal. Foot Ankle 1991;11:350-353.
Coughlin MJ: Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with distal soft tissue repair. Foot Ankle 1991;11:195-203.
Kitaoka HB, Holiday AD Jr: Metatarsal head resection for bunionette: Long-term follow-up. Foot Ankle 1991;11:345-349.

Question 32

A year-old patient fell 3 weeks after undergoing a total hip arthroplasty using cementless fixation of the femoral component. She sustained a comminuted Vancouver type B-2 fracture with displacement of the calcar fragment. What is the best treatment option?

Explanation

DISCUSSION:
The patient has an acute postoperative fracture of the proximal femur with subsidence. It is also common that the stem retroverts relative to the femur. It is most often seen in proximally porous coated stems within 90 days of surgery, one paper found it to occur 0.7% of the time in modern implants. There is always a debate whether this is a missed intraoperative fracture, or a new fracture that has resulted from an event of increased hoop stresses. Removal of the primary stem, placement of a diaphyseal engaging
stem (most frequently a tapered-fluted stem), and cabling of the fracture is the most successful treatment.

Question 33

A 40-year-old woman underwent an arthroscopic acromioplasty and mini-open rotator cuff repair 4 weeks ago. At follow-up examination, the incision is painful, erythematous, and draining fluid. The patient is febrile and has an elevated WBC count. What infectious organism should be under high suspicion of causing this outcome?

Explanation

DISCUSSION: Proprionobacter acnes has been a leading cause of indolent shoulder infections. During shoulder arthroscopy, the arthroscopic fluid may actually dilute the shoulder preparation and lead to a higher rate of infection during subsequent mini-open rotator cuff repair surgery. The remaining bacteria listed are rarely associated with shoulder infections after arthroscopy.
REFERENCES: Herrera MF, Bauer G, Reynolds F, et al: Infection after mini-open rotator cuff repair. J Shoulder Elbow Surg 2002;11:605-608.
Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 551-557.

Question 34

Figures 36a and 36b show the radiographs of a 48-year-old woman who smokes cigarettes and sustained a segmental femoral shaft fracture in a motor vehicle accident 9 months ago. Initial management consisted of stabilization with a reamed statically locked intramedullary nail. She now reports lower leg pain that increases with activity. In addition to advising the patient to quit smoking, management should include

Explanation

DISCUSSION: The patient has an oligotrophic nonunion of the distal femoral fracture. Although the proximal fracture appears incompletely united, it was stable at exchange nailing. The treatment of choice is exchange reamed nailing to at least 2 mm above the nail in place. Bone grafting is debatable. Recent studies have shown a 70% to 75% success rate with exchange nailing only, so in nonhypertrophic nonunions, bone grafting can be considered. Nonsurgical management consisting of observation or external stimulation runs the risk of implant failure. Plate fixation is acceptable but is considered a second choice because of the need to consider stabilization of the proximal fracture until union is achieved. Also, plate fixation definitely requires bone grafting.
REFERENCES: Webb LX, Winquist RA, Hansen ST: Intramedullary nailing and reaming for delayed union or nonunion of the femoral shaft: A report of 105 consecutive cases. Clin Orthop 1986;212:133-141.
Weresh MJ, Hakanson R, Stover MD, et al: Failure of exchange reamed intramedullary nailing for ununited femoral shaft fractures. J Orthop Trauma 2000;14:335-338.
Hak DG, Lee SS, Goulet JA: Success of exchange reamed intramedullary nailing for femoral shaft nonunion or delayed union. J Orthop Trauma 2000;14:178-182.

Question 35

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

Explanation

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

Question 36

A professional baseball team has several pitchers with complaints of velocity loss with their pitches and shoulder pain of their dominant shoulders during spring training. Pitch counts are properly monitored. The average glenohumeral internal rotation deficit on the pitching staff is 45 degrees. The best intervention would be: Review Topic

Explanation

Glenohumeral Internal Rotation Deficit (GIRD) is a phenomenon that occurs in baseball pitchers and is due to posterior capsular tightness. Treatment should begin with a therapy program addressing the pathologic posterior capsule.
GIRD is a phenomenon that is frequently found in high-level overhead throwing athletes, predominantly baseball pitchers. It is defined as the measured difference in internal rotation between the non-dominant arm and dominant arm. Worsening range of motion deficits are seen with increased repetitions, both over a single season and a career. GIRD > 25º is associated with development of shoulder pathologies or pain requiring periods of inactivity. Cessation of overhead throwing activities and initiation of a stretching program to address posterior capsular contractures is largely effective (90% in some series).
Burkhart et al. reviewed the conditions associated with high-level overhead throwing athletes shoulders, culminating in a theory of pathologic progression to "dead arm syndrome" (loss of velocity and effective pitching). Their theory attributes adaptive hyperexternal rotation (occurs during late-cocking / early acceleration phases of pitching) to lead to posterior-inferior capsular contracture and GIRD. Subsequent injuries to anterior structures - including SLAP lesions - would then occur.
Illustration A is a cartoon depiction of how to perform the sleeper stretch. This is a common component of a pitcher's maintenance stretching program.
Incorrect Answers:

Question 37

Figures 12a through 12e show the radiograph, MRI scans, and biopsy specimens of a 17-year-old boy. What is the most likely diagnosis?

Explanation

DISCUSSION: The images show an epiphyseal lesion. The MRI scan shows extensive bone edema surrounding the lesion, consistent with chondroblastoma. Histology shows polygonal chondroblasts in a cobblestone-like pattern and areas of calcification consistent with chondroblastoma. Although some giant cells are seen, the age of the patient and the polygonal chondroblasts differentiate this lesion from giant cell tumor. Clear cell chondrosarcoma is an epiphyseal lesion that occurs in an older population, and the cells have clear cytoplasm. This lesion is not producing bone on imaging or histologic specimen, eliminating osteosarcoma. Tuberculous septic arthritis can be an epiphyseal lesion, but granulomas would be seen on histology.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Campanacci M: Bone and Soft Tissue Tumors, ed 2. New York, NY, Springer-Verlag, 1999,

pp 247-263.

Question 38

A 57-year-old man has had a 2-week history of neck pain. He has no history of radiating symptoms, and has no complaints of numbness or paresthesias. There was no trauma associated with the onset of the pain. Figure 26 shows the MRI scan initially obtained by his family physician. What should the patient be told regarding the prevalence of the MRI findings in his age group? Review Topic

Explanation

The MRI findings reveal age-related degenerative changes in the cervical spine, which is a very common finding in the adult population. Boden and associates evaluated cervical spine MRI findings on 63 asymptomatic subjects, and found that the prevalence of having at least one degenerative disk was approximately 57% in those older than age 40 years.

Question 39

A total shoulder arthroplasty (TSA) would be the most appropriate treatment in which of the following arthritic patients? Review Topic

Explanation

A total shoulder arthroplasty (TSA) is indicated in the 72 year old male with debilitating shoulder pain and an intact rotator cuff on MRI. The other patient scenarios are examples of contraindications for TSA.
A TSA involves replacement of the humeral head with a metal head and resurfacing of the glenoid to a cemented all-polyethylene surface. In order to achieve optimal results, patients must be selected carefully. Patients with an irreparable rotator cuff tear, non-functioning deltoid, inadequate glenoid bone stock and brachial plexopathy
are poor candidates for TSA.
Edwards et al. conducted a multicenter randomized controlled trial to compare TSA versus hemiarthroplasty in patients with primary osteoarthritis of the shoulder. They found that TSA provided better scores for pain, mobility, and activity than hemiarthroplasty at 2 year follow-up.
Boileau et al. followed 45 consecutive patients who underwent reverse TSA (rTSA) for cuff tear arthropathy (CTA), post-traumatic arthritis, and failure of revision arthroplasty. After a mean follow-up of 40 months, they found that the reverse prosthesis improved function and was able to restore active elevation in patients with incongruent cuff-deficient shoulders. They also found that the results were less predictable and complication and revision rates were higher in patients undergoing revision surgery as compared to those patients undergoing rTSA for CTA.
Illustrations A and B show the preoperative and postoperative x-rays of a patient with characteristic OA of the glenohumeral joint that was treated with TSA.
Incorrect Answers:

Question 40

What structure is located at the tip of the arrow in Figure 18? Review Topic

Explanation

The structure shown is the exiting nerve root at the L3-4 disk, which is the right L3 root.

Question 41

Which of the following shoulder girdle muscles is most active during forward flexion?

Explanation

The percentage of recorded EMG activity indicates the level of activity of a given muscle but does not indicate the force generated. During forward elevation, the upper portion of the trapezius, levator scapulae, and serratus anterior contract to produce a scapular rotating force upward, increasing the stability of the glenohumeral joint. The essential muscles for forward elevation are the deltoid, the supraspinatus, the trapezius and the serratus anterior. EMG reveals the serratus to be most active.

Question 42

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

Explanation

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

Question 43

The Coleman block test is used to test for Review Topic

Explanation

The Coleman block test is used to determine the flexibility of the hindfoot. When a block is placed under the lateral border of the foot, the medial column is unsupported. As a result, the first metatarsal drops off the side of the block. If the subtalar joint is flexible, there is no fixed varus deformity of the hindfoot. The hindfoot will no longer be in varus from behind. The varus deformity of the hindfoot will be corrected. If there is no subtalar motion, the varus deformity remains fixed.

Question 44

An 11-year-old child has a tibia-fibula fracture following a fall from a swing. The fracture is reduced and placed in a long leg splint in the emergency room. What is considered the most important symptom of a developing compartment syndrome of the leg?

Explanation

DISCUSSION: The Willis reference states “the single most important symptom of impending compartment syndrome is pain out of proportion to the injury." This symptom requires a conscious patient. Most children requiring a reduction for a displaced upper or lower extremity fracture will become comfortable soon after the reduction has been completed. Children requiring frequent analgesia or complaining loudly about pain should be examined very carefully for possible compartment syndrome.” The key wording in this question is “earliest indicator”. Pulselessness, paralysis, pallor, and parasthesias are all late indicators.
The Willis article also lists the most reliable signs of a developing compartment syndrome as severe pain with passive stretching of the involved compartment, pain with palpation of the involved compartment, sensory disturbances

Question 45

A 58-year-old woman sustained a ruptured Achilles tendon 1 year ago, and management consisted of an ankle-foot orthosis. She now reports increasing difficulty with ambulation and increasing pain. An MRI scan shows a 6-cm defect in the right Achilles tendon. Management should now consist of

Explanation

DISCUSSION: With a gap of less than 4 cm, a V-Y repair would be appropriate without a tendon transfer. For gaps greater than 5 cm, a lengthening with augmentation is the most appropriate treatment. Therefore, the treatment of choice is an Achilles tendon turndown with flexor hallucis longus tendon transfer. The plantaris tendon is not a strong enough repair, and direct repair is not possible given the large defect in the Achilles tendon. Continued use of the ankle-foot orthosis will not provide adequate relief for this patient.
REFERENCE: Myerson MS: Achilles tendon ruptures. Instr Course Lect 1999;48:219-230.

Question 46

Figures 1 through 3 show the radiograph and MR arthrograms obtained from a 25-year-old woman who has had right groin pain since joining the military 4 years ago. She has undergone treatment with NSAIDs, physical therapy, and activity modification. Examination reveals positive flexion abduction and external rotation, a positive external log roll, and increased range of motion. What is the most appropriate treatment?

Explanation

DISCUSSION:
This patient has symptomatic hip dysplasia that has been recalcitrant to nonsurgical management. Radiographs reveal an upsloping sourcil (acetabular index of 18) and a lateral center edge angle of 14, with posterior uncovering. The MR arthrogram shows no definitive evidence of a labral tear. Appropriate surgical management would include periacetabular osteotomy. Viscosupplementation in the hip is controversial in the treatment of osteoarthritis and plays no role in the treatment of dysplasia. Hip arthroscopy with labral repair is controversial in mild hip dysplasia, with studies demonstrating between 60% and 77% good and excellent results, inferior to the results for hip arthroscopy in a femoroacetabular impingement cohort. In moderate to severe dysplasia, hip arthroscopy is not recommended. Because the acetabular cartilage is well maintained, total hip arthroplasty would not be recommended in this young and active patient.

Question 47

A 65-year-old man with ankylosing spondylitis sustains an extension injury to his cervical spine. Two days later, a progressive neurologic deficit develops at the C6 level. An MRI scan is shown in Figure 1. What is the most likely diagnosis?

Explanation

DISCUSSION: It is common for patients with ankylosing spondylitis to sustain extension-type fractures, typically near the cervicothoracic junction. These fractures can be minimally displaced, making them difficult to diagnose. In addition, the vertebral bodies are vascular and their canals are relatively enclosed, making them vulnerable to epidural bleeding. The MRI scan shows an epidural hematoma posteriorly compressing the cord.
REFERENCES: Bohlman HH: Acute fractures and dislocations of the cervical spine. J Bone Joint Surg Am 1979;61:1119-1142.
Weinstein PR, Karpman RR, Gall EP, et al: Spinal cord injury, spine fracture and spinal stenosis in ankylosing spondylitis. J Neurosurg 1982;57:609-616.
Johnson T, Steinbach L (eds): Essentials of Musculoskeletal Imaging. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, p 44.

Question 48

A patient who sustained injuries in a motorcycle accident 30 minutes ago has significant motor and sensory deficits corresponding to a C6 level of injury. A lateral radiograph obtained during the initial on-scene evaluation reveals bilateral jumped facets at C5-C6; this appears to be an isolated injury. The patient is awake and alert. The next step in management of the dislocation should consist of

Explanation

DISCUSSION: Surgical open reduction may increase the neurologic deficit if a disk herniation exists. Evidence from animal studies suggests that rapid decompression of the spinal cord may improve recovery. Serially increasing traction weight to reduce the dislocation has been shown to be safe when used in patients who are awake. Indications for MRI include patients who are unable to cooperate with serial examinations, the need for open reduction, and progression of deficit during awake reduction.
REFERENCES: Delamarter RB, Sherman J, Carr JB: Pathophysiology of spinal cord injury: Recovery after immediate and delayed decompression. J Bone Joint Surg Am

1995;77:1042-1049.
Star AM, Jones AA, Cotler JM, Balderston RA, Sinha R: Immediate closed reduction of cervical spine dislocations using traction. Spine 1990;15:1068-1072.
Eismont FJ, Arena MJ, Green BA: Extrusion of an intervertebral disc associated with traumatic subluxation or dislocation of cervical facets: Case report. J Bone Joint Surg Am

1991;73:1555-1560.

Question 49

A 58-year-old man has anterior knee pain after undergoing total knee arthroplasty for osteoarthritis 2 years ago. He denies any history of trauma. A Merchant view is shown in Figure 20. What is the most likely cause of his pain?

Explanation

DISCUSSION: The patient has a patellar stress fracture after resurfacing in a total knee arthroplasty. Several studies have shown that over-resection of the patella to less than 12 to 15 mm increases anterior patellar surface strains to a point where the risk of fracture is increased. Increasing the patellar thickness, positioning of the femoral component, lateral releases, and component types have not been clearly associated with increased fracture risk.
REFERENCES: Reuben JD, McDonald CL, Woodard PL, Hennington LJ: Effect of patella thickness on patella strain following total knee arthroplasty. J Arthroplasty 1991;6:251-258.
Hsu HC, Luo ZP, Rand JA, An KN: Influence of patellar thickness on patellar tracking and patellofemoral contact characteristics after total knee arthroplasty. J Arthroplasty 1996;11:69-80.
Greenfield MA, Insall JN, Case GC, Kelly MA: Instrumentation of the patellar osteotomy in total knee arthroplasty: The relationship of patellar thickness and lateral retinacular release. Am J Knee Surg 1996;9:129-131.

Question 50

Long bone fracture repair following intramedullary stabilization occurs primarily through which of the following healing mechanisms?

Explanation

DISCUSSION: The mechanical environment represents a major factor in the type of healing that occurs after a fracture. Intramedullary nail fixation allows for motion at the fracture site, which promotes bone formation both directly (intramembranous ossification) and through a cartilage intermediate (endochondral ossification). Absolute stability, as would be obtained with a compression plate, favors healing through the direct formation of bone without a cartilage intermediate (intramembranous ossification), or primary fracture repair. This type of healing would include the remodeling of the bone ends through the direct contact of bone, often referred to as contact healing or haversian remodeling.
REFERENCES: 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 385-386.
Buckwalter JA, Einhorn TA, Bolander ME: Healing of the musculoskeletal tissues, in Rockwood CA Jr, Green DP, Bucholz RW, et al (eds): Rockwood and Green’s Fractures in Adults, ed 4. Philadelphia, PA, Lippincott-Raven, 1996, pp 261-276.

Question 51

9 degress Celsius, serum WBC is 14,000, and his C-reactive protein is elevated. He reports that he uses IV heroin. A coronal 3D CT scan of the left clavicle is shown in Figure B. Joint aspiration shows many grams stain positive organisms. Which of the following organisms is the most likely pathogen?

Explanation

Tibial eminence fracture
Sagittal plane fracture of the medial femoral condyle
Schatzker I tibia plateau fracture
Coronal plane fracture of the lateral femoral condyle
Axial plane fracture through the medial femoral condyle Correct answer: 4
The "Hoffa fracture" is a coronal plane fracture of the femoral condyle that is often missed on plain radiographs of supracondylar and intercondylar femur fractures. It involves the lateral condyle more frequently than the medial.
Identification is important as it may impact operative planning and likely require screw fixation in the anteroposterior plane.
Nork et al. reviewed 202 supracondylar-intercondylar distal femoral fractures and found a 38% prevalence of associated coronal plane fractures. The authors recommend CT scan imaging of all supracondylar and intercondylar fractures.
Ostermann et al reported on 24 unicondylar fractures of the distal femur treated with open reduction internal fixation with a screw construct. Twenty-
three patients acheived satisfactory results at 5 year follow-up. Illustrations A and B are another example of a supracondylar femur fracture with an associated Hoffa fracture identified on CT scan.

A 35-year-old woman presents with an elbow injury which includes a coronoid fracture involving more than 50%, a comminuted
radial head fracture, and an elbow dislocation. What is the most appropriate treatment?
closed reduction and early range of motion
radial head resection and lateral collateral ligament reconstruction
radial head resection and coronoid open reduction internal fixation
radial head arthroplasty and coronoid open reduction internal fixation
radial head arthroplasty, coronoid open reduction internal fixation, and lateral collateral ligament repair
A terrible triad of the elbow includes dislocation of the elbow with associated fractures of the radial head and the coronoid process. Ring et al. stressed that these injuries are prone to complications and advised against resection of the radial head due to instability, and instead recommended a radial head replacement if too comminuted for ORIF. Coronoid fractures compromise elbow stability as well and require open reduction and internal fixation as with the lateral collateral ligament. McKee et al. showed stable elbows in 34/36 with mean Mayo elbow score of 88 when the standard protocol of coronoid ORIF, radial head repair/replacement, and LCL repair were employed.
The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:
perpendicular to the medial clear space
parallel to the talar body
between the tips of the malleoli
perpendicular to the shaft of the fibular
parallel to the subtalar joint Correct answer: 3
The talocrural angle is formed by the intersection of a line perpendicular to the plafond with a line drawn between the malleoli (average = 83+/-4deg). When the lateral malleolus is shortened secondary to fracture, this can lead to increased talocrural angle. This malunion leads to lateral tilt of the talus.
Phillips et al looked at 138 patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture. Although the conclusions were limited due to poor follow up, they found the difference in the talocrural angle between the injured and normal sides was a statistically significant radiographic indicator of a good prognosis.
Pettrone et al looked at a series of 146 displaced ankle fractures, and the effect of open or closed treatment, and internal fixation of one or both malleoli. They found open reduction proved superior to closed reduction, and in bimalleolar fractures open reduction of both malleoli was better than fixing only the medial side.
Illustrations A and B are demonstrations of the talocrural angle.

A 33-year-old male sustains the injury shown in Figure A. He is initially treated with a spanning external fixator followed by definitive open reduction internal fixation of the tibia and fibula. His wounds healed without infection or other complications. Two years following surgery, which of the following parameters will most likely predict a poor clinical outcome and inability to return to work?

Joint line restoration
Degree of fracture displacement
Time before definitive ORIF
Open fracture
Lower level of education Correct answer: 5
Lower level of education is the parameter that correlated most closely with a poor clinical outcome and inability to return to work.
To determine what fracture- and patient-specific variables affect outcome, Williams et al evaluated 29 patients with 32 tibial plafond fractures at a minimum of 2 years from the time of injury. Outcome was assessed by four independent measures: a radiographic arthrosis score, a subjective ankle score, the Short Form-36 (SF-36), and the patient’s ability to return to work. The four outcome measures did not correlate with each other. Radiographic arthrosis was predicted best by severity of injury and accuracy of reduction. However, these variables did not show any significant relationship to the clinical ankle score, the SF-36, or return to work. These outcome measures were more influenced by patient-specific socioeconomic factors. Higher ankle
scores were seen in patients with college degrees and lower scores were seen in patients with a work-related injury. The ability to return to work was affected by the patient’s level of education.
Pollak et al performed a retrospective cohort analysis of pilon fractures. Patient, injury, and treatment characteristics were recorded. The primary outcomes that were measured included general health, walking ability, limitation of range of motion, pain, and stair-climbing ability. A secondary outcome measure was employment status. Multivariate analyses revealed that presence of two or more comorbidities, being married, having an annual personal income of less than $25,000, not having attained a high-school diploma, and having been treated with external fixation with or without limited internal fixation were significantly related to poorer results as reflected by at least two of the five primary outcome measures.
What is the most appropriate treatment for a 17-year-old boy who sustained a gunshot wound to his forearm from a handgun with a muzzle-velocity of 1000 feet/second if he is neurovascularly intact and radiographs reveal no fracture?
Irrigation and local wound care in the emergency department
Emergent irrigation and debridement in the operating room with vacuum-assisted wound closure
Emergent irrigation and debridement in the operating room with 7 days of intravenous antibiotics
Wound closure in the emergency department with follow-up wound check in 1 week
Exploration and removal of all bullet fragments in the emergency department and 10 day course of oral antibiotics
The question refers to appropriate management of a gunshot wound to the forearm. The first question that must be answered when evaluating gunshot injuries is whether the gunshot is low velocity or high velocity. Low-velocity wounds are less severe, are more common in the civilian population, and are typically attributed to bullets with muzzle velocities below 1,000 to 2,000 feet per second. Tissue damage is usually more substantial with higher-velocity (greater than 2,000 to 3,000 fps) military and hunting weapons. In this question, a muzzle velocity of 1,000 ft/sec is provided. Low velocity injuries with stable, non-operative fractures can be treated with local wound care.
The two referenced articles offer guidance for treating low-velocity gunshot injuries with stable, non-operative fracture patterns. The first article by Geissler et al is a retrospective study comparing 25 patients that prospectively received local irrigation and debridement, tetanus prophylaxis and a long acting cephalosporin intramuscularly to a random retrospective sample of 25 patients with similar ballistic-induced fractures and wounds managed by local debridement and 48h of intravenous antibiotics. One infection occurred in each group, requiring further therapy. It was concluded that patients with low-velocity gunshot induced fractures can be managed without the use of short-term intravenous antibiotics with no increased risk of infection.
In the second study, Dickey et al evaluated the efficacy of an outpatient management protocol for patients with a gunshot-induced fracture with a stable, non-operative configuration. 41 patients with a grade I or II open, nonoperative fracture secondary to a low-velocity bullet were treated with 1gm of cefazolin administered in the emergency room and a 7-day course of oral cephalexin. No patient developed a deep infection. Thus, local I&D, tetanus, and oral antibiotics for 2-3 days is adequate for low velocity gunshot wounds.
Which clinical sign is the most sensitive for the diagnosis of compartment syndrome in a child with a supracondylar humerus fracture?
pulselessness
pallor
paresthesia
paralysis
increasing analgesia requirement Correct answer: 5
Although pain, pallor, paresthesia, paralysis, and pulselessness are all possible signs and symptoms of compartment syndrome in children with fractures, studies have shown increasing analgesia requirement is more sensitive.
Bae et al reviewed thirty-six cases of compartment syndrome in 33 pediatric patients. Approximately 75% of these patients developed compartment syndrome in the setting of fracture. "They found pain, pallor, paresthesia, paralysis, and pulselessness were relatively unreliable signs and symptoms of compartment syndrome in these children. An increasing analgesia requirement in combination with other clinical signs, was a more sensitive indicator of
compartment syndrome."
Whitesides et al summarizes the diagnosis and treatment of acute compartment syndrome. They emphasize the need for early diagnosis, as "muscles tolerate 4 hours of ischemia well, but by 6 hours the result is uncertain; after 8 hours, the damage is irreversible." They recommend fasciotomy be performed when tissue pressure rises past 20 mm Hg below diastolic pressure.
A 45-year-old man sustains the injury seen in Figures A and B following a motor vehicle accident. Postoperative radiographs are seen in Figures C and D. Which of the following is the most accurate when comparing outcomes between intramedullary nailing (IMN) and open reduction internal fixation (ORIF) for this injury?

Union rates at one year are higher with ORIF
Infection rates are higher with IMN
Functional shoulder outcomes at one year are equivalent with IMN and ORIF
Iatrogenic radial nerve injury rate is higher with ORIF
Shoulder stiffness rates at one year are equivalent with IMN and ORIF Correct answer: 3
Although shoulder pain and stiffness is increased following IMN compared to ORIF, functional outcome scores at one year have been shown to be equivalent
in both treatment groups.
Diaphyseal humeral shaft fractures outcomes following IMN and ORIF are under further investigation. Diaphyseal humeral shaft fractures have historically been treated with ORIF, however proponents for IMN cite benefits of less periosteal stripping and soft tissue dissection. Recent investigations have shown outcomes with regard to nonunion, infection, re-operation, and nerve palsy appear equivalent between both groups. Rates of shoulder stiffness and shoulder pain have been demonstrated to be higher in IMN compared to ORIF. American Shoulder and Elbow Scores (ASES) have shown no difference at one year post-operatively.
Bhandari et al. performed a meta-anaylsis of 3 prospective randomized trials. They found lower rates of re-operation and shoulder impingement with ORIF of humeral shaft fractures.
Wali et al. performed a prospective randomized study of IMN or ORIF on 50 patients with mid-diaphyseal humeral shaft fractures. They found IMN had shorter operative time, shorter hospital stay, and lower blood loss. They found no difference in union rates, complication, or shoulder functional outcomes scores. They conclude IMN to be an effective option for treating mid-diaphyseal humeral shaft fractures.
Heineman et al. have recently conducted an update on their meta-analysis to include more recent randomized studies. With the inclusion of newer studies the author found a statistically significant increase in total complication rate with the use of IM nailing compared with ORIF. The authors found no significant difference between the two treatment modalities for the secondary outcomes (nonunion, infection, nerve palsy, re-operation).
Figures A and B show a diaphyseal humeral shaft fracture. Figure C and D show postoperative radiographs following intramedullary nailing of a humeral shaft fracture.
Incorrect Answers:
A 25-year-old female presents complaining of progressive anteromedial pain in her left ankle. She underwent operative fixation 5 months prior at an outside hospital. The operative report indicated that, due to anterior fracture blisters, a direct medial incision was utilized, centered over the posterior colliculus of the medial malleolus, without violation of the deltoid ligament. A radiograph and computed tomographic scan of her initial injury are shown in Figures A and B, respectively. On exam, she has well-healed incisions, exhibits no tenderness to palpation over her hardware, but does endorse pain with deep palpation along the anteromedial joint line. Figure C shows an anteroposterior left ankle radiograph taken today. Labs are obtained and reveal a white blood cell count of 9.0 k/uL (reference range 4.5-11.0 k/uL) and a C-reactive protein value of 0.8 mg/dL (<0.9 mg/dL). What is the next best step in managing her problem?

Syndesmotic fixation
Intra-articular corticosteroid injection
Referral to physical therapy
Surgical correction of malunion
Removal of hardware Correct answer: 4
This patient sustained a supination-adduction (SAD) injury with a vertical shear fracture of her medial malleolus and a fibular avulsion fracture. She sustained a medial plafond articular impaction injury that was not addressed at the time of surgery.
In SAD injuries, supination of the foot is combined with inward rotation at the ankle, adduction of the hindfoot, and inversion of the forefoot. This results in the following sequence of events: 1. Talofibular sprain or distal fibular avulsion (equivalent to Weber A). 2. Vertical medial malleolus fracture as the talus strikes the tibia. Associated injuries may include osteochondral damage to the talus and marginal impaction of the medial plafond. It is important to evaluate the medial plafond for articular impaction. When present, an arthrotomy must be performed, typically utilizing an anteromedial incision, with direct visualization of the articular surface to restore the joint line appropriately.
Weber et al. provided a review article on corrective osteotomies for malleolar fracture malunions. They stress that malunions can lead to ankle instability, abnormal load transfer, and post-traumatic arthritis. They conclude that corrective osteotomies that restore anatomical alignment show good results in long-term follow-up.
Perera et al. provided additional commentary on the surgical reconstruction of malunited ankle fractures. The authors emphasize the link between malunion and poor outcomes. They state that successful salvage procedures involve a clear understanding of the deformity, careful preoperative planning, and a solid understanding of reconstructive techniques. They provide several instructive case examples in their review.
McConnell et al. provided a discussion on SAD ankle fractures at their institution and emphasized the importance of recognizing marginal impaction of the tibial plafond when treating these injuries. Of 800 ankle fractures identified over a 5-year period, 44 were SAD injuries, 19 of the 44 displayed a vertical shear fracture of the medial malleolus, and 8 of the 19 demonstrated marginal impaction of the tibial plafond. These 8 impaction injuries were treated with open reduction internal fixation with elevation of the articular impaction; all had good to excellent outcomes without arthritic changes at last
follow-up.
Figure A is an anteroposterior left ankle radiograph demonstrating a SAD injury with a vertical shear fracture of the medial malleolus, a fibular avulsion fracture, and articular impaction of the medial tibial plafond. Figure B is a coronal CT demonstrating articular impaction of the medial plafond. Illustration A is an intra-operative photograph with the medial malleolus retracted allowing inspection of the articular surface; mild anteromedial plafond impaction is present.
Incorrect Answers:

A 90-year-old female slips and falls at home. She is a community ambulator and has no medical problems. She reports right hip pain at this time. Injury radiographs are shown in Figures A & B. Delay of more than 48 hours may result in:

Increased intraoperative time
Increased 30-day mortality
No impact on the rate of postoperative pneumonia
Higher rates of blood transfusion
Increased risk of post-operative infection Correct answer: 2
Figures A & B demonstrate a right, unstable intertrochanteric femur fracture. Surgical stabilization within 48 hours improves short-term and 30-day mortality.
Hip fractures are common and mortality rates vary. In the elderly, mortality rates may reach 10% at 1-month, 20% at 4-months, and 30% at 1-year. Time to surgery has found to be a decisive factor. A pre-operative delay may lead to an increase in mortality and adversely influence other clinical outcomes.
Clinical guidelines recommend immediate operative stabilization, given the patient is medically fit for surgery.
Nyholm et al. performed a retrospective study of the Danish Fracture Database to investigate whether a surgical delay increases 30-day and 90-day mortality rates for patients with proximal femoral fractures. The 30-day and 90-day mortalities were 10.8% and 17.4%, respectively. The risk of 30-day mortality increased with increasing time intervals of more than 12 hours, 24 hours, and more than 48 hours. 90-day mortality increased with a surgical delay of more than 24 hours. They conclude that rapid surgical treatment should be performed by attending orthopaedic surgeons.
Moja et al. performed a meta-analysis and meta-regression to assess the relationship between surgical delay and mortality in elderly patients with a hip fracture. They analyzed 35 independent studies with 191,873 patients and 34,448 deaths. The majority of studies had a cut-off of 48 hours. They report that early hip surgery was associated with a lower risk of death and pressure sores. They conclude that early hip fracture surgery appears to provide a survival benefit compared to later intervention.
Rodriguez-Fernandez et al. performed a study examining 2 groups with hip fractures. The first group was studied retrospectively and had an average delay of surgical treatment of more than 1-week while the second group was studied prospectively, and had surgical treatment within 48 hours. They found a larger number of complications in the group with a delay in surgical treatment. They conclude that elderly patients with hip fractures should be treated as soon as their medical condition permits.
Figures A and B are the AP and lateral radiographs demonstrating a right, unstable intertrochanteric femur fracture. Illustration A is an intertrochanteric femur fracture, stabilized with a cephalomedullary nail.
Incorrect Answers:

A 22-year-old healthy left hand dominant male presents to the ED with left shoulder pain after falling from an ATV. Figure A is the radiograph of his left clavicle. He is neurovascularly intact and there is no evidence of skin tenting or open fracture. Which of the following most predisposes this patient to nonunion?

Diaphyseal fracture
Fracture displacement
Age
Male Gender
Injury involving the dominant extremity Correct answer: 2
Displaced clavicle fractures are associated with higher rates of nonunion.
Nonunion occurs in roughly 5-6% of clavicle fractures and can result in slower functional return, poor cosmesis and muscle fatigability. Clavicle fractures can be sub-classified using the Allman classification into medial, diaphyseal, and lateral injuries (Illustration A). The Neer classification for diaphyseal injuries describes fractures as "nondisplaced" (less than 100% displacement) and "displaced" (greater than 100% displacement).
Robinson et al. performed a prospective cohort study to identify risk factors for nonunion after nonoperative management of clavicle fractures. The overall nonunion rate was 6.2% and was highest in lateral third fractures (11.5%).
Diaphyseal fractures had the lowest nonunion rate (4.5%). Additionally, the authors found that the risk for nonunion was increased by advancing age, female gender, fracture displacement, and comminution.
Jorgensen et al. performed a systemic review of the literature looking for predictors of non-union and malunion in mid shaft clavicle fractures treated non-operatively. They found fracture comminution, displacement, older age, female gender, and the presence of smoking to be his factors for non-union. Of these, displacement was the most likely factor that can be used to predict nonunion.
Figure A demonstrates a displaced left clavicle diaphyseal fracture. Note that the medial fragment is displaced superiorly by the deforming force of the sternocleidomastoid. Illustration A represents the Allman classification.
Illustration B demonstrates the deforming forces acting on the clavicle.
Incorrect Answers:

A 24-year-old male presents with ankle pain after being involved in a motor vehicle accident. His injury radiograph is shown in Figure A. Which of the following has been shown to contribute to the development of post-traumatic arthritis in this injury pattern?

Initial superficial zone cartilage cell death via apoptosis at the fracture margins
Initial superficial zone cartilage cell death via apoptosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis at the fracture margins
Delayed superficial zone cartilage cell death via necrosis at the fracture margins
Figure A demonstrates a tibial plafond fracture. Initial superficial zone cartilage cell death via necrosis at the fracture margins has been shown to contribute to post-traumatic arthritis.
Post-traumatic osteoarthritis typically occurs after an intra-articular fracture. Impacted chondrocytes die by either necrosis or apoptosis, which have both been implicated in post-traumatic osteoarthritis. Initial cell death in the superficial cartilage zones at the fracture margins occurs by necrosis. Apoptosis occurs in a delayed fashion and is mitigated by several bioactive agents.
Apoptosis also affects the superficial cartilage zones near the fracture margins. Deep cartilaginous zones and areas away from the fracture margins do not seem to be involved in these processes.
McKinley et al. performed a review of the basic science of intra-articular fractures and posttraumatic osteoarthritis. They report that initial damage to the cartilage in combination with the ensuing pathomechanical and pathobiologic response of the cartilage after a fracture contribute to posttraumatic arthritis. Chronic abnormal joint loading is also thought to contribute to this process as well. They conclude that the relative contribution of each is unknown.
Tochigi et al. performed a study to determine the distribution and progression of chondrocyte damage after intra-articular ankle fractures. They harvested 7 normal human ankles and subjected them to impaction. They found that immediate superficial zone chondrocyte death was greater in fracture-edge regions than on-fracture regions. Subsequent cell death over the next 48 hours was significantly higher in fracture-edge regions as well. They conclude that cartilage damage in intra-articular fractures was characterized by chondrocyte death at fracture margins.
Figure A is an ankle mortise radiograph demonstrating an intra-articular tibial plafond fracture.
Incorrect Answers:
A 35-year-old male presents with left knee pain after sustaining the injury seen in Figure A. He is neurovascularly intact and can perform a straight leg raise, but has pain with passive range of motion. Figures B and C show an anteroposterior and lateral radiograph of the left knee, respectively. 175 cc of saline is injected into the superolateral quadrant with no egress of fluid from the inferolateral
laceration. What percentage of traumatic arthrotomies would be detected with this test?

Question 52

In a retroperitoneal approach to the lumbar spine, what nerve is commonly found on the psoas muscle?

Explanation

DISCUSSION: The genitofemoral nerve and the sympathetic plexus consistently lie on the ventral surface of the psoas muscle. The ilioinguinal and iliohypogastric nerves are the most superior branches of the lumbar plexus and emerge along the upper lateral border of the psoas muscle traveling toward the quadratus lumborum. Both the obturator and femoral nerves are deep and lateral to the psoas muscle.
REFERENCES: Watkins RG (ed): Surgical Approaches to the Spine, ed 1. New York, NY, Springer-Verlag, 1983, p 107.
Johnson R, Murphy M, Southwick W: Surgical approaches to the spine, in Herkowitz HH (ed): The Spine, ed 4. Philadelphia, PA, WB Saunders, 1992, p 1559.
Gray’s Anatomy. New York, NY, Bounty Books, 1977, pp 1226-1227.

Question 53

Which of the following primary prognostic factors best predicts the outcome of the knee lesion shown in Figure 22?

Explanation

DISCUSSION: The patient has osteochondritis dissecans. While location, size, and knee stability are all relevant to the overall prognosis, studies have shown that younger patients with open growth plates have a better prognosis of healing when compared with patients who have closed growth plates. The degree of pain is also relevant to treatment, but it is subjective rather than objective and is not as reliable of a prognostic indicator as age.
REFERENCES: Stanitski CL: Osteochondritis dissecans of the knee, in Stanitski CL, DeLee JC, Drez D Jr (eds): Pediatric and Adolescent Sports Medicine. Philadelphia, PA, WB Saunders, 1994, vol 3, pp 387-405.
Cahill B: Treatment of juvenile osteochondritis dissecans and osteochondritis dissecans of the knee. Clin Sports Med 1985;4:367-384.
Linden B: Osteochondritis dissecans of the femoral condyles: A long-term follow-up study. J Bone Joint Surg Am 1977;59:769-776.

Question 54

A 49-year-old woman noted pain in her right axilla 1 day after moving heavy furniture. Two weeks later, she now reports persistent numbness and paresthesias along the inner aspect of her upper arm radiating into the ulnar digits. Examination reveals full shoulder motion, tenderness over the first rib, and a decreased radial pulse with the shoulder placed overhead. What is the most likely diagnosis?

Explanation

DISCUSSION: Thoracic outlet syndrome is thought to be caused by compression of the neurovascular supply to the upper limb in the supraclavicular and axillary regions of the shoulder. While typically progressive in onset, thoracic outlet syndrome may develop after acute injury. Injury or weakness of the scapular muscles, especially the trapezius, may result in descent of the scapula and cause compression of the thoracic outlet. In general, most symptoms are the result of neural compression. Typical symptoms include pain in the neck or shoulder and numbness or tingling that predominantly involves the ulnar side of the arm and hand. Exacerbation of these symptoms is typical when the arm is abducted. Initial management should consist of postural exercises aimed at restoring proper scapular stability. Severe recalcitrant symptoms may warrant surgical decompression.
REFERENCES: Leffert RD: Thoracic outlet syndrome. J Am Acad Orthop Surg 1994;2:317-325.
Todd TW: The descent of the shoulder after birth: Its significance in the production of pressure-symptoms on the lowest brachial trunk. Anat Anz 1912;41:385-397.

Question 55

An 85-year-old obese woman has left knee pain. She had surgery 5 years ago for a patellar nonunion after total knee arthroplasty that was complicated by infection, which was treated with implant removal and patellectomy. She has not been ambulatory since then. She states she is no longer on antibiotics. She has moderate pain, but her primary problem is instability of the knee. She has a 40° extensor lag. Darkening of the skin is present distal to the incision consistent with venous stasis changes. The erythrocyte sedimentation rate is 12 mm/h (reference range 0 to 20 mm/h) and her C-reactive protein level is 1.0 mg/L (reference range 0.08 to 3.1 mg/L). Left knee aspiration shows a white blood cell count of 800 and 20% neutrophils. What is the best next step?

Explanation

DISCUSSION:
This patient is elderly, obese, and nonambulatory and has a chronic quadriceps tendon rupture after infected total knee arthroplasty. Her potential for ambulation after revision total knee arthroplasty is very low. Primary repair of the tendon is unlikely to be successful, even with augmentation, so revision total knee arthroplasty with primary quadriceps tendon repair and two-stage revision knee arthroplasty and quadricep repair with Achilles allograft are not the best management techniques. Extensor mechanism allograft could be done but would have a high failure rate in a patient of this size. No sign of infection is seen, based on laboratory studies, so a two-stage procedure is not necessary. The best management although not optimal, would be treatment in a drop-lock brace. Arthrodesis is also an option, but would have a high complication rate, and in a patient that is nonambulatory, a fused knee would be increasingly
difficult with activities of daily living and mobility.

Question 56

A 46-year-old woman reports pain and a shortened appearance of her toe after undergoing a Keller resection arthroplasty 2 years ago for hallux rigidus. Examination reveals mild swelling and motion limited to 25 degrees at the metatarsophalangeal joint. Radiographs show large dorsal osteophytes on the first metatarsal head, 50% resection of the proximal phalanx, and complete loss of the metatarsophalangeal joint space. Which of the following is considered the most reliable procedure to improve her pain and the appearance of her toe?

Explanation

DISCUSSION: Because the patient has significant arthritis, arthrodesis is the treatment of choice. Adding a bone graft will prevent further shortening and add length to her toe, resulting in improved cosmesis. A cheilectomy will not alleviate her arthritis pain. The toe is too short for an effective Moberg phalangeal dorsiflexion osteotomy. A Waterman first metatarsal dorsal osteotomy will not address the degenerative joint disease or shortening. Silastic arthroplasty may help, but there is the risk of additional problems with foreign body reaction and a significant risk of failure known to occur with Silastic materials.
REFERENCES: Myerson MS, Schon LC, McGuigan FX, Oznur A:Result of arthrodesis of the hallux metatarsophalangeal joint using bone graft for restoration of length. Foot Ankle Int 2000;21:297-306.
Mann RA, Coughlin MJ: Adult hallux valgus, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 252-253.
Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 293-303.

Question 57

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 58

Figure 1 is the MR image of a 36-year-old athlete who is tackled from behind and falls forward onto his left knee. He has pain, swelling, and stiffness. Examination includes a moderate effusion, positive quadriceps active test, and normal Lachman test finding. This patient elects nonsurgical treatment and later experiences persistent instability. Examination reveals an asymmetric Dial test finding and a varus thrust during ambulation. Which osteotomy and correction appropriately addresses this chronic instability pattern?

Explanation

The clinical description and MR image point to an injury to the posterior cruciate ligament (PCL). This ligament is thought to be primarily composed of anterolateral and posteromedial bundles, with the former tightening in flexion and the latter in extension. Because of alterations in knee kinematics and increased varus alignment in PCL insufficiency, contact stresses and cartilage loads increase in the patellofemoral and medial compartments. Although good outcomes may be obtained with transtibial, open inlay, and arthroscopic inlay techniques, one major difference is the creation of the “killer-turn” during the transtibial approach. This sharp turn in the graft as it emerges from the tibia appears to lead to more pronounced attenuation and thinning of the graft during cyclic loading. The scenario describes a patient with chronic PCL and posterolateral corner (PLC) injury, as evidenced by the varus thrust and abnormal Dial test finding. A valgus-producing osteotomy may be effective, and, in fact, may be the only treatment necessary to address chronic PLC injury. Accordingly, an opening lateral osteotomy would not be appropriate. Of the remaining responses, an osteotomy that increases tibial slope would also address the PCL deficiency by reducing posterior tibial sag. Vascular injury is an uncommon, but potentially devastating, complication associated with PCL surgery and may occur regardless of the technique used.
Numerous strategies have been described to reduce the risk, including use of a posteromedial accessory incision to allow finger retraction of the popliteal neurovascular bundle, oscillating drills to prevent excessive soft-tissue entanglement, and tapered (rather than square) drill bits that may minimize cut-out of sharp edges as drilling reaches the posterior tibial cortex. Knee extension lessens, rather than increases, the distance between the posterior tibia and the neurovascular bundle and increases, not lessens, risk for vascular injury.

Question 59

What is the most common non-anesthetic-related reversible cause of sustained changes in intraoperative neurophysiologic monitoring signals during spinal surgery? Review Topic

Explanation

Patient positioning that results in local nerve compression, plexus traction, or improper neck alignment is the most common non-anesthetic-related cause of changes in intraoperative neurophysiologic monitoring data during spinal surgery. Pedicle screw malpositioning, spinal cord ischemia, and retractor placement are all less common causes. Hypotension, not hypertension, can be a cause of intraoperative neurophysiologic changes.

Question 60

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 61

Which of the following statements most accurately describes the layers of articular cartilage?

Explanation

DISCUSSION: Normal articular cartilage is composed of three zones that are based on the shape of the chondrocytes and the distribution of the type II collagen. The tangential zone has flattened chondrocytes, condensed collagen fibers, and sparse proteoglycan. The intermediate zone is the thickest layer with round chondrocytes oriented in perpendicular or vertical columns paralleling the collagen fibers. The basal layer is deepest with round chondrocytes. The tidemark is deep to the basal layer and separates the true articular cartilage from the deeper cartilage that is a remnant of the cartilage anlage, which participated in endochondral ossification during longitudinal growth in childhood. The tidemark divides the superficial uncalcified cartilage from the deeper calcified cartilage and also is the division between nutritional sources for the chondrocytes. The tidemark is the zone in which chondrocyte renewal took place in childhood. The tidemark is found only in joints and not in the cap of an enchondroma. It is seen most prominently in the adult, nongrowing joint.
REFERENCE: Schiller AL: Pathology of osteoarthritis, in Kuettner KE, Goldberg VM (eds): Osteoarthritic Disorders. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1995,

pp 95-101.

Question 62

What clinical finding is associated with the least favorable prognosis in an adolescent patient who has been diagnosed with a high-grade osteosarcoma of the distal femur?

Explanation

DISCUSSION: The presence of synchronous bone disease in young patients carries a dismal prognosis, one that is even worse than the presence of resectable pulmonary metastasis. Many osteosarcomas cross the physis; therefore, this has not been shown to be of prognostic importance. Similarly, the presence of the soft-tissue mass has less prognostic significance.
REFERENCE: Mirra JM: Bone Tumors: Clinical, Radiologic, and Pathologic Correlation. Philadelphia, PA, Lea and Febiger, 1989, pp 344-350.

Question 63

Figure below depicts the radiograph obtained from a 30-year-old woman who began having more right than left hip pain during a recent pregnancy. Physical examination reveals increased range of motion with positive flexion abduction and external rotation and flexion adduction and internal rotation as well as pain with external logroll. Assessment of Figure below reveals

Explanation

DISCUSSION:
Studies have demonstrated that pelvic inclination can dramatically affect the interpretation of radiographs in the dysplastic hip, with 9° of increased pelvic inclination leading to the presence of crossover signs and posterior wall signs. A distance of 30 mm to 50 mm from the sacrococcygeal junction to the pubis is often used to assess the adequacy of pelvic inclination on radiographs, although Siebenrock and associates determined the mean difference to be 32 mm in men and 47 mm in women. In this patient, the pelvic inclination is dramatically increased, leading to overestimation of acetabular retroversion.

Question 64

A 16-year-old cheerleader reports an ache in the right shoulder and arm that is worse after activity. She denies any history of acute trauma. Examination reveals a positive sulcus sign and an AP glide test with a posterior and anterior apprehension sign. To confirm a diagnosis of multidirectional instability, which of the following imaging studies is most appropriate?

Explanation

DISCUSSION: Multidirectional instability is a common finding in young female athletes. The anatomic structures are all intact but are hypermobile; therefore, CT and bone scans and scapular Y-views are often normal. Obtaining a weighted or AP stress view while applying downward traction on the arm will document instability and hypermobility of the joint. MRI generally is not indicated in this condition. Ultrasound is used primarily for rotator cuff pathology.
REFERENCES: Neer CS II, Foster CR: Inferior capsular shift for involuntary inferior and multidirectional instability of the shoulder: A preliminary report. J Bone Joint Surg Am 1980;62:897-908.
Warner JJ, Johnson D, Miller M, Caborn DN: Technique for selecting capsular tightness in repair of anterior-inferior shoulder instability. J Shoulder Elbow Surg 1995;4:352-364.

Question 65

A 10-year-old boy with spastic diplegic cerebral palsy walks in a crouched position with the hips and knees flexed. Maximum knee flexion is 15 degrees during early swing phase. Instrumented gait analysis shows quadriceps activity from terminal stance throughout swing phase. Treatment should consist of

Explanation

DISCUSSION: The rectus femoris muscle spans two joints and is active during running, sprinting, and walking at a fast pace during the preswing and early swing phase of gait. In these situations, the muscle helps to generate power to initiate hip flexion while absorbing or controlling the rate of knee flexion during early swing phase. Quadriceps activity, including the rectus femoris, is not normally needed when walking at a routine cadence. However, rectus femoris activity is commonly noted during preswing and the swing phase in patients with cerebral palsy, particularly those with diplegia. In an effort to initiate swing phase, the rectus femoris is “overactive.” As a result, the knee flexion that commonly occurs at terminal stance and initial swing is restricted. Instead of achieving the normal 50 to 60 degrees of flexion during early swing, this patient’s knee flexion is limited to 15 degrees. The goal of treatment is to retain rectus femoris activity for initiation of hip flexion but to diminish its restraint on knee flexion. Studies have shown that transfer of the distal rectus femoris tendon provides more flexion of the knee during the swing phase of gait than simply releasing the tendon. V-Y lengthening of the quadriceps tendon or a Z lengthening of the patellar tendon causes too much weakening of the quadriceps muscle and worsens the crouch deformity. In addition to transfer of the rectus femoris tendon, other procedures are often done concomitantly to obtain the best balance and realignment of hip-knee-ankle activity.
REFERENCES: Aiona MD: Guidelines for managing lower extremity problems in cerebral palsy, in Fitzgerald RH, Kaufer H, Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1534-1541.
Chambers H, Laure A, Kaufman K, Cardelia M, Sutherland D: Prediction of outcome after rectus femoris surgery in cerebral palsy: The role of cocontraction of the rectus femoris and vastus lateralis. J Pediatr Orthop 1998;18:703-711.
Ounpuu S, Muik E, Davis RB, Gage JR, Deluca PA: Rectus femoris surgery in children with cerebral palsy. J Pediatr Orthop 1993;13:331-335.

Question 66

Figures 2a and 2b show the clinical photograph and radiograph of a 16-year-old cheerleader who fell on her left lower extremity while performing a pyramid. Following adequate sedation, closed reduction is performed, but an incomplete reduction is noted. What structure is most likely preventing a reduction?

Explanation

DISCUSSION: The stretched peroneus brevis muscle and tendon follow anterior to the fibula and are most likely incarcerated with reduction. The anterior talofibular ligament is too small to prevent reduction of the ankle joint itself. The extensor digitorum brevis originates from the talus; therefore, it is not involved in the tibiotalar joint. The posterior tibial tendon lies medially and would not be interposed into the ankle joint. Similarly, the anterior tibialis tendon also would not be involved.
REFERENCES: Pehlivan O, Akmaz I, Solakoglu C, et al: Medial peritalar dislocation. Arch Orthop Trauma Surg 2002;122:541-543.
Rivera F, Bertone C, De Martino M, et al: Pure dislocation of the ankle: Three case reports and literature review. Clin Orthop 2001;382:179-184.

Question 67

In the normal adult, the distance between the basion and the tip of the dens with the head in neutral position is how many millimeters?

Explanation

DISCUSSION: In the normal adult, the distance between the basion and the tip of the dens is 4 mm to 5 mm. Any distance greater than 5 mm is considered abnormal. This is one way to detect occipitocervical dissociation other than using the Power’s ratio, which relies on an anterior dislocation.
REFERENCES: Wiesel SW, Rothman RH: Occipitoatlantal hypermobility. Spine 1979;4:187-191.
Wholey MH, Browner AJ, Baker HL Jr: The lateral roentgenogram of the neck: With comments on the atlanto odontoid-basion relationship. Radiol 1958;71:350-356.

Question 68

A patient has a C6-7 herniated nucleus pulposus. What is the most likely distribution of symptoms? Review Topic

Explanation

Hyperextension
Flexion-distraction
Flexion-compression
Rotational
Pure axial load
Figure A shows a quadrangular fracture pattern of C5. These injuries are observed with flexion-compression loads.
Quadrangular fractures of the cervical spine are considered flexion teardrop fractures. However, they present with a larger anterior lip fragment compared to the classic teardrop fracture pattern. The radiographic findings include a quadrangular-shaped fragment from the anterior one-third of the vertebral body with significant posterior vertebral subluxation, angular kyphosis, and an increased interspinous space with facet subluxation due to disruption of the posterior elements. These are unstable fractures, and almost always require anterior and posterior stabilization.
Moore et al. studied the reliability of Cervical Spine Injury Severity Score to measure stability after cervical spine trauma. The classification system is based on morphologic descriptions and, secondly, on stability based on a quantifiable value. They showed that the Cervical Spine Injury Severity Score had excellent reliability with intra-observer intraclass correlation coefficients (ICC) >0.97 and inter-observer ICC >0.88.
Vaccaro et al. published the subaxial cervical spine injury classification system (SLIC). This systems involves 3 main categories (injury morphology, disco-ligamentous complex, and neurologic status). The overall injury severity score is obtained by summing the scores from each category. They propose that SLIC < 4 can be treated non-operatively.
Allen et al. published a classification system of cervical spine injuries which breaks injuries of the subaxial spine into six phylogenic groups based on mechanism of injury. These include: 1) flexion-compression 2) vertical-compression 3) flexion-
distraction 4) extension-compression 5) extension-distraction 6) lateral flexion. Facet
dislocation
is
caused
by
flexion-distraction
force.
Figure A shows a lateral radiograph of the cervical spine demonstrating a typical flexion-compression fracture with anteriorly displaced quadrangular fragment. Illustration A shows a flexion-compression injury. Illustration B shows the mechanism of injury for a quadrangular fracture of the cervical spine. This unstable fracture pattern is characterized by anterior column failure in flexion/compression and posterior column failure in tension. Illustration C shows an illustration of the fracture morphology according to the Allen and Ferguson classification.
Incorrect Answer 1:
Hyperextension injuries
Flexion-distraction injuries usually result in facet dislocations.

Question 69

A 47-year-old woman has had a 1-month history of left hip and medial thigh pain that is exacerbated by sitting. Laboratory studies show a total protein level of 8.2 g/dL (normal 6.0 to 8.0) and an immunoglobulin G (IGG) level of 2,130 mg/dL (normal 562 to 1,835). A radiograph, CT scan, and biopsy specimen are shown in Figures 38a through 38c. What is the most likely diagnosis?

Explanation

DISCUSSION: The laboratory studies and histology are both consistent with myeloma. Infection should show white blood cells other than plasma cells on histology. Lymphoma would show lymphocytes, not plasma cells. The lack of bone formation on the imaging studies and the lack of osteoid on histology rule out osteosarcoma. The cells have too much cytoplasm and nuclear chromatin to be Ewing’s sarcoma cells.
REFERENCE: Mirra J: Bone Tumors: Clinical, Radiologic, and Pathologic Correlations. Philadelphia, PA, Lea & Febiger, 1989, vol 2, ch 16.

Question 70

Figure 51 shows an arthroscopic view of the patellofemoral joint from an inferolateral portal. The arrow points to which of the following structures? Review Topic

Explanation

Synovial folds or plicae are the result of incomplete or partial resorption of the synovial membranes during fetal development of the knee. The arthroscopic view shows a medial patellar plica, which has been noted in 5% to 55% of all individuals but becomes symptomatic in only a small number of patients. Symptoms may include crepitus, pain, snapping, and swelling and often respond to nonsurgical management.

Question 71

What is the primary problem in rickets osteomalacia?

Explanation

Rickets is a disorder of bones in children that results from decreased calcium available in the blood resulting in poor mineralization of bone that can lead to fractures and deformity. The most common cause of rickets is from vitamin D deficiency but it can also be caused by poor nutrition or gastrointestinal disease that results in poor calcium absorption such as celiac disease or severe diarrhea from other causes. Rickets is not primarily a physeal disorder. Osteogenesis imperfecta is caused by a defect in type I collagen. A defect in the ext-1 gene is often seen in patients with multiple hereditary exostoses. Fibrous dysplasia also can result in bone deformity and fractures due to production of dysplastic fibrous bone but is not caused by calcium or vitamin D deficiency.

Question 72

CLINICAL SITUATION Figure 1 is the radiograph taken 6 weeks ago of a 41-year-old woman with persistent pain in her right leg after sustaining a tibia fracture 12 months ago in a motor vehicle collision. On examination, she has well-healed scars and a well-healed flap on the medial aspect at the level of the fracture. She reports having an infection after the initial surgery, which resulted in debridement of the soft tissue and need for the local rotational flap. There are no changes at the fracture site as shown in the most recent radiograph (Figure 2). She is healthy and has no comorbidities. What is the best next step in the patient’s evaluation?

Explanation

Discussion: The patient had an open fracture that was initially treated with what appears to be appropriate irrigation and debridement and intramedullary nail placement. The post-operative infection and need for rotational flap is worrisome,
but she has not had any issues since the flap. She has abundant callus formation but the fracture line is still visible and unchanged on 2 sets of radiographs. The patient has persistent pain. The best initial evaluation is to ensure that there is no underlying infection with laboratory studies, including a complete blood count (CBC), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Nuclear medicine studies have questionable utility, but may be helpful if the inflammatory markers from laboratory studies come back elevated. A CT scan is not warranted because the sequential radiographs show persistent fracture lines and no changes. The patient has a hypertrophic nonunion. Originally, she had appropriate treatment and has shown the ability to make callus, thus her biologic capacity appears to be intact and bone grafting is not needed. The hypertrophic nature of her fracture nonunion indicates that she needs more stability. The best treatment for a hypertrophic nonunion of the tibia is exchange nailing. Based on successive radiographs and the lack of healing, observation is probably just delaying the inevitable. Plating with retention of the nail can be useful in recalcitrant long bone non-union, especially in the femur.

Question 73

In revision total hip arthroplasty, an acetabular reconstruction cage is best indicated for which of the following patterns of bone loss?

Explanation

DISCUSSION: Acetabular cage reconstruction is indicated in severe disruption of acetabular bone stock when a cementless acetabular component cannot be stabilized in intimate contact with a sufficient bed of structurally sound and viable host bone, with or without a structural graft. Cages are used in pelvic discontinuity where they provide a bridge between the ilium and the ischium, while supporting a cemented cup. All of the other scenarios are amenable to achieving an adequate rim fit for a cementless component, using a jumbo cup if necessary.
REFERENCES: Whiteside LA: Selection of acetabular component, in Steinberg ME, Garino JP (eds): Revision Total Hip Arthroplasty. Philadelphia, PA, Lippincott Williams and Wilkins, 1999, pp 209-220.
Berry DJ, Muller ME: Revision arthroplasty using an anti-protrusio cage for massive acetabular bone deficiency. J Bone Joint Surg Br 1992;74:711-715.

Question 74

Figure 28 shows the postoperative radiograph of a 36-year-old patient. The cerclage cable was placed for a minimal medial calcar fracture seen during femoral preparation. In the immediate postoperative period, what is the highest level of activity that would be safely permitted?

Explanation

DISCUSSION: The incidence of femoral fracture in primary cementless total hip arthroplasty ranges from 1.5% to 27.8%. It is imperative that the implant and fracture are stable both intraoperatively and postoperatively. Cerclage wiring or cerclage cabling is the current recommended treatment for nondisplaced calcar fractures and minimally displaced proximal fractures. Berend and associates reviewed the results of 58 total hips in 55 patients with intraoperative calcar fracture managed with single or multiple cerclage wires or cables and immediate full weight bearing. Follow-up averaged 7.5 years, and there were no revisions of the femoral component. No patients had severe thigh pain.
REFERENCES: Berend KR, Lombardi AV Jr, Mallory TH, et al: Cerclage wires or cables for the management of intraoperative fracture associated with a cementless, tapered femoral prosthesis: Results at 2 to 16 years. J Arthroplasty 2004;19:17-21.
Schmidt AH, Kyle RF: Periprosthetic fractures of the femur. Orthop Clin North Am 2002;33:143-152.
Greidanus NV, Mitchell PA, Masri BA, et al: Principles of management and results of treating the fractured femur during and after total hip arthroplasty. Instr Course Lect 2003;52:309-322.

Question 75

A 4-year-old girl sustains an isolated spiral femoral fracture after falling from her tricycle. Management should consist of

Explanation

DISCUSSION: Immediate spica casting is ideal for younger children with uncomplicated femoral fractures that are the result of relatively low-energy injury. Surgical stabilization of pediatric femoral fractures is most commonly performed in children who are older than age 6 years or in children with other factors associated with their femoral fracture, such as concomitant head injury, open fracture, floating knee, severe comminution, or vascular injury.
REFERENCES: Flynn JM, Skaggs DL, Sponseller PD, et al: The surgical management of pediatric fractures of the lower extremity. Instr Course Lect 2003;52:647-659.
Sponseller PD: Surgical management of pediatric femoral fractures. Instr Course Lect 2002;51:361-365.
Wright JG: The treatment of femoral shaft fractures in children: A systematic overview and critical appraisal of the literature. Can J Surg 2000;43:180-189.
Levy J, Ward WT: Pediatric femur fractures: An overview of treatment. Orthopedics 1993;16:183-190.

Question 76

..Figure 93 is the radiograph of a 72-year-old woman. Treatment includes fixation of the ulna. What options are recommended for the radius?

Explanation

CLINICAL SITUATION FOR QUESTIONS 94 THROUGH 96

Figure 94 is the anteroposterior radiograph of a 75-year-old woman who has a 5-year history of progressive pain, crepitus, and loss of motion in her shoulder. She had a rotator cuff repair 10 years ago. Examination reveals 60 degrees of active forward elevation and 20 degrees of external rotation with her arm at her side. Passively she can be brought to 160 degrees of forward elevation and 90 degrees of external rotation with her arm at her side. A glenohumeral joint injection with local anesthetic eliminated pain, but there is no observed change in active motion.

Question 77

Figures 43a and 43b show the AP and lateral radiographs of the radius and ulna of a 9-year-old patient. The fracture is manipulated and placed in a long arm cast with the elbow flexed to 90 degrees and the forearm to neutral rotation. Figures 43c and 43d show the alignment of the fracture after the manipulation. What is the next most appropriate step in management?

Explanation

DISCUSSION: By placing the forearm at neutral rotation, as shown in Figures 43c and 43d, the distal fragment has become malrotated by 90 degrees. This is evident by the fact that the bicipital tuberosity is rotated 90 degrees to the radial styloid. Normally, it should be directly opposite (180 degrees) to the radial styloid. The correct alignment was present in the original radiographs shown in Figures 43a and 43b. Another clue to the malrotation in the postreduction radiographs is the difference in the diameters of the opposing radial shafts. To correct this rotational malalignment, the distal fragment needs to be remanipulated into supination so that it is correctly aligned with the supinated proximal radius.
REFERENCES: Evans EM: Fractures of the radius and ulna. J Bone Joint Surg Br 1951;33:548-561.
Milch H: Roentgenographic differentiation between torsion and rotational fractures of the forearm. Bull Hosp Jt Dis 1949;10:216-225.

Question 78

A 47-year-old obese man with a body mass index of 42 comes into the office with left knee pain 1 year after undergoing an uncomplicated left medial unicompartmental knee arthroplasty (UKA). Radiographs show a loose tibial component in varus. What is the most appropriate next step to treat this failed construct?

Explanation

DISCUSSION:
This patient likely is experiencing failure of the UKA secondary to poor patient selection. In this young, heavy man, the component likely loosened due to the ongoing varus alignment of the knee and his elevated
weight. Despite this likely scenario, the next step is determining whether an infection is the cause of his pain. Prior to obtaining an aspiration, the surgeon can order ESR and CRP studies to determine whether aspiration is warranted. If the laboratory studies are unremarkable, the surgeon likely can forgo the aspiration and proceed to a revision TKA with possible augments on standby.

Question 79

The difference between vitamin D-dependent rickets type I (VDDR I) and vitamin D-dependent rickets type II (VDDR II) is

Explanation

VDDR I is a deficiency of an enzyme predominantly found in the kidney. VDDR II is caused by an inactivating mutation of the receptor for 1,25 (OH)2 vitamin D3.
VDDR I is a deficiency of 1a-hydroxylase [converts 25(OH)D to 1a,25(OH)2D3].
Lab tests show hypocalcemia, secondary hyperparathyroidism, elevated alkaline phosphatase (ALP) and low or undetectable calcitriol in the presence of adequate 25(OH)D levels. VDDR II or hereditary vitamin D resistant rickets (HVDRR) (autosomal recessive) is an inactivating mutation in the vitamin D receptor (VDR). Lab tests show low serum calcium and phosphate, elevated ALP and secondary hyperparathyroidism. Serum 25(OH)D values are normal and the 1,25(OH)2D levels are elevated (key difference from VDDR I).
Malloy et al. reviewed genetic disorders in vitamin D action. They state that VDDR I is an inborn error of vitamin D metabolism coded by the gene CYP27B1. Children with VDDR I present with joint pain/deformity, hypotonia, muscle weakness, growth failure, and hypocalcemic seizures or fractures in early infancy. Treatment is with calcitriol or 1a-hydroxyvitamin D (NOT cholecalciferol). Children with VDDR II present with bone pain, muscle weakness, hypotonia, hypocalcemic convulsions, growth retardation, severe dental caries or teeth hypoplasia. Affected children are resistant to therapy and supra-physiologic doses of all forms of vitamin D.
Illustration A shows the differences between VDDR I and VDDR II. Incorrect Answers
in the kidney). The liver enzyme vitamin D 25-hydroxylase (found in hepatocytes) is not responsible for VDDR. VDDR II is caused by an inactivating mutation (rather than an activating mutation).

Question 80

Augmentation of a Broström repair with the mobilized lateral portion of the extensor retinaculum (Gould modification) is expected to produce

Explanation

Multiple biomechanical studies have investigated the contribution of the Gould modification with the Broström anatomic repair for chronic ankle instability. No studies to date have demonstrated a statistically significant difference in initial ankle stability with inclusion of the Gould modification or augmentation of the repair with a mobilized lateral portion of the extensor retinaculum. No clear association exists between the Broström-Gould repair technique and risk for nerve injury, postsurgical range of motion, or incidence of osteoarthritis on long-term follow-up.

Question 81

In which scenario is application of NPWT contraindicated?

Explanation

DISCUSSION
The most common complication associated with NPWT is a rash on the skin resulting from contact with a suction sponge. In a 2001 study by Webb and Schmidt, 2.2% of patients treated with NPWT had a rash that resolved within 48 hours. To minimize risk for this rash, care should be taken to avoid overlap of the sponge onto intact skin. If skin overlap is unavoidable, a lower-pressure setting should be used.
Acute bacterial infection is possible in this scenario, but there would likely be additional findings such as purulence in the wound itself. Similarly, an acute allergic reaction could be found within the wound and not just at the skin edge. Skin irritation from excessive adhesive plastic tension can result in blistering or shearing avulsion but not skin-edge erythema. Skin necrosis from the original trauma would result in skin-edge duskiness instead of erythema.
A study by Timmers and associates showed a statistically significant increase in microvascular blood flow to the skin under a sponge at subatmospheric pressures. Angiogenesis occurs in the area of the wound vacuum from the negative pressure and increased blood flow, not from the sponge material itself. There has been no indication that antibiotic concentration is increased in the setting of negative pressure therapy because antibiotics would be evacuated along with the fluid. NPWT does not result in increased temperatures that would kill pathogens.
NPWT is contraindicated in the setting of neoplasm because its effect on tumors is unknown. There is potential for increased angiogenesis in residual tumor cells, which could lead to recurrence or even metastasis. NPWT has been used safely and effectively for coverage of open fractures between initial debridement and definitive coverage. Fasciotomy wounds are frequently covered with NPWT dressings on a temporary basis with excellent results.
NPWT has been used to temporize wounds with exposed bone before flap coverage. Wounds with excessive tension frequently can be closed after short-term coverage with NPWT dressings.
RECOMMENDED READINGS
Webb LX, Schmidt U. [Wound management with vacuum therapy]. Unfallchirurg. 2001 Oct;104(10):918-26. German. PubMed PMID: 11699301.View Abstract at PubMed
Webb LX. New techniques in wound management: vacuum-assisted wound closure. J Am Acad Orthop Surg. 2002 Sep-Oct;10(5):303-11. PubMed PMID: 12374481. View Abstract at PubMed
Timmers MS, Le Cessie S, Banwell P, Jukema GN. The effects of varying degrees of pressure delivered bynegative-pressure wound therapy on skin perfusion. Ann Plast Surg. 2005 Dec;55(6):665-71. PubMed PMID: 16327472. View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 68 AND 69

Figure 68 is the radiograph of a 17-year-old girl who is treated with closed reduction and percutaneous screw fixation for her displaced femoral neck fracture. Capsulotomy of the hip is not performed. After surgery, the patient is instructed to maintain touch-down weight-bearing status for 3 months.

Question 82

A 25-year-old student sustains the injury shown in Figures 13a through 13c after falling off a curb. Initial management should consist of

Explanation

DISCUSSION: The radiographs reveal a fracture entering the 4-5 intermetatarsal articulation, consistent with a zone 2 injury. This classically is also referred to as a Jones fracture. The history and radiographic findings indicate this is an acute fracture, which guides management. A zone 1 fracture enters the fifth tarsometatarsal joint, and a zone 3 fracture is a proximal diaphyseal fracture distal to the 4-5 articulation. Initial management is usually nonsurgical and consists of non-weight-bearing in a short leg cast. This method has been shown to result in a better healing rate compared to weight bearing as tolerated.
REFERENCES: Rosenberg GA, Sterra JJ: Treatment strategies for acute fractures and nonunions of the proximal fifth metatarsal. J Am Acad Orthop Surg 2000;8:332-338.
Lawrence SJ, Botte MJ: Jones’ fracture and related fractures of the proximal fifth metatarsal. Foot Ankle 1993;14:358-365.

Question 83

When performing surgery on a patient with insertional Achilles tendinitis and a Haglund’s deformity, how much of the Achilles tendon insertion can be safely detached without having to consider reattachment with bone anchors?

Explanation

DISCUSSION: The Achilles tendon insertion encompasses a broad area on the posterior area of the calcaneus. A biomechanical study has shown that up to 50% of the Achilles tendon insertion point can be detached before the strength of the attachment point starts to weaken. It is recommended that if more than this amount is detached to remove the posterior superior calcaneal prominence, consideration should be given to either securing the tendon to the bone with suture anchors or performing a tendon transfer.
REFERENCES: Kolodziej P, Glisson RR, Nunley JA: Risk of avulsion of the Achilles tendon after partial excision for treatment of insertional tendinitis and Haglund’s deformity: A biomechanical study. Foot Ankle Int 1999;20:433-437.
Sammarco GJ, Taylor AL: Operative management of Haglund’s deformity in the nonathlete: A retrospective study. Foot Ankle Int 1998;19:724-729.

Question 84

Creatine is currently being used by athletes as a dietary supplement in an attempt to enhance performance. What is the physiologic basis for its use?

Explanation

DISCUSSION: Creatine is currently used as a nutritional supplement in an attempt to enhance athletic performance. The physiologic basis for its use is based on its conversion by CK to PCr, which acts as an energy reservoir in muscle cells for the production of ATP. A number of studies that examined the effect of creatine supplementation on performance concluded that while creatine does not increase peak force production, it can increase the amount of work done in the first few anaerobic short duration, maximal effort trials. The mechanism for this enhancement of work is unknown, but it is most likely secondary to the increase in the available PCr pool.
REFERENCES: Greenhaff PL: Creatine and its application as an ergogenic aid. Int J Sport Nutr 1995;5:S100-S110.
Greenhaff PL, Casey A, Short AH, Harris R, Soderlund K, Hultman E: Influence of oral creatine supplementation on muscle torque during repeated bouts of maximal voluntary exercise in man. Clin Sci 1993;84:565-571.
Trump ME, Heigenhauser GJ, Putman CT, Spriet LL: Importance of muscle phosphocreatine during intermittent maximal cycling. J Appl Physiol 1996;80:1574-1580.
Hultman E, Soderlund K, Timmons JA, Cederblad G, Greenhaff PL: Muscle creatine loading in men. J Appl Physiol 1996;81:232-237.

Question 85

-The patient experienced little improvement with activity modification and physical therapy. An intraarticular corticosteroid injection provides excellent but short-lived pain control. She requests surgical treatment for her hip and she is counseled regarding arthroscopy and consent is obtained. Intraoperatively,a capsulolabral separation is observed with an underlying pincer lesion. No articular cartilage injury is seen. What treatment is most appropriate considering these findings?

Explanation

DISCUSSION FOR QUESTIONS 26 THROUGH 29
The clinical scenario, examination, and MRI scans are consistent with a pincer-type FAI. The decreased range of motion is secondary to the pain produced by the continued abutment of the femoral head against the anterosuperior acetabulum. Flexing the hip while internally rotating and adducting the leg recreates this contact and is typically painful. No clinical signs suggest sacroiliac joint arthritis, an intra-articular loose body, or trochanteric bursitis, although these are all diagnoses that should be considered in a patient with a painful hip. The most sensitive and specific study to detect an acetabular labral tear is an MRI arthrogram of the hip. This study should be obtained in this patient to evaluate the labrum as well as the status of the articular cartilage. An MRI scan without intra-articular contrast is not as sensitive as an arthrogram. An ultrasound can provide a dynamic assessment of the hip and help in the setting of a snapping hip; however, this study is not reliable to determine the presence of a labral tear. In the setting of pincer FAI, the forced leverage of the anterosuperior femoral head upon the anterior acetabulum results in abnormal forces against the posteroinferior acetabulum. This continued force can lead to a chondral lesion in this location know as a “counter-coup” injury. Chondral lesions of the femoral head are rare in the setting of pincer FAI. The posterosuperior quadrant does not experience increased force and rarely sustains chondral injuries. The patient is a young, active individual with no pre-existing degenerative changes, so repair of the tear with bony resection of the pincer lesion is the most appropriate treatment.A capsulolabral detachment should be repaired because these tears can heal and the labrum functions as a seal, preventing egress of synovial fluid from the joint space. If the pincer lesion is not resected, the patient will continue to experience abnormal contact and the repair will likely fail. There is no evidence that the patient has a cam impingement, and recontouring of the femoral head/neck junction is not appropriate. Simple debridement should be reserved for intrasubstance tears of the labrum, which would not be expected to heal with repair.
CLINICAL SITUATION FOR QUESTIONS 30 THROUGH 32
Figures 30a and 30b are the radiographs of a 20-year-old college multisport athlete who has had longstanding pain in his left hip. He denies any specific event that initiated his pain, but he notes that he had hip problems when he was an infant. He denies pain with activities of daily living, but he
believes his pain is increasingly limiting his ability to exercise. He localizes the pain to his groin. He denies low-back or buttock pain or pain that radiates down his leg.

Question 86

Which of the following preoperative findings is a predictor of poor outcome following arthroscopic debridement for glenohumeral arthritis? Review Topic

Explanation

Studies have shown that patients with moderate to severe degenerative changes of the glenohumeral joint fare worse than those with a concentric joint space. Preoperative stiffness and presence of loose bodies have correlated with successful results. A history of infection or instability, in the absence of degenerative changes has not been correlated with poorer outcomes.

Question 87

Figures 1 through 3 demonstrate the radiographs obtained from a 25-year-old man who injured his right, by punching a wall 3 weeks earlier. He notes pain and deformity about the ulnar aspect of his hand. The best treatment option is

Explanation

EXPLANATION:
The initial radiographs reveal a fourth and fifth carpometacarpal (CMC) joint fracture dislocation. The injury is associated with a shear fracture of the dorsal rim of the hamate. Further assessment with CT might be helpful in fully evaluating the extent of injury. Extensor carpi ulnaris is a deforming force at the base of the fifth metacarpal. This unstable fracture dislocation could be treated with closed reduction and pinning if the patient presented within a few days of injury. However, because he presented in a delayed fashion (3 weeks after injury), open reduction with internal fixation was required (Figures 4 and 5). In the series by Zhang and associates, patients with fourth and fifth CMC fracture dislocations presenting in a delayed fashion and treated nonsurgically had suboptimal results. Therefore, closed reduction and casting are not appropriate. An arthrodesis and resection arthroplasty are salvage procedures considered for a painful arthritic joint and would less likely should not be considered for this acute injury.

Question 88

A 29-year-old man who lifts weights states that he injured his left shoulder while performing a bench press 2 days ago. The following morning he noted ecchymosis and swelling in the left chest wall. Examination reveals ecchymosis and tenderness and deformity in the left anterior chest wall and axillary fold that is accentuated with resisted adduction of the arm. Passive range of motion beyond 90 degrees of forward flexion and 45 degrees of external rotation is extremely painful. Glenohumeral stability is difficult to assess because of severe guarding. Figure 29 shows an MRI scan. Management should consist of

Explanation

DISCUSSION: Rupture of the pectoralis major tendon most commonly occurs during bench pressing. Wolfe and associates have shown that the most inferiorly located fibers of the sternal head lengthen disproportionately during the final 30 degrees of humeral extension during the bench press. This creates a mechanical disadvantage in the final portion of the eccentric phase of the lift; with forceful flexion of the shoulder these maximally stretched fibers may rupture. In most patients, particularly in young athletes, the treatment of choice is anatomic repair of the ruptured tendon to its insertion in the proximal humerus either with suture anchors or transosseous sutures. Following surgery, most patients experience a near normal return of strength and significant improvement in the cosmetic appearance of the deformity. While more technically challenging, repair of chronic rupture is possible and is indicated in some patients.
REFERENCES: Wolfe SW, Wickiewicz TL, Cavanaugh JT: Ruptures of the pectoralis major muscle: An anatomic and clinical analysis. Am J Sports Med 1992;20:587-593.
Schepsis AA, Grafe MW, Jones HP, Lemos MJ: Rupture of the pectoralis major muscle: Outcome after repair of acute and chronic injuries. Am J Sports Med 2000;28:9-15.

Question 89

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

Explanation

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

2006;88:113-120.
Iannotti JP, Hennigan S, Herzog R, et al: Latissimus dorsi tendon transfer for irreparable posterosuperior rotator cuff tears. J Bone Joint Surg Am 2006;88:342-348.

Question 90

A 16-year-old girl sustained the injury shown in Figure 7a. CT scans are shown in Figures 7b through 7d. The results of treatment of this injury have been shown to most correlate with which of the following factors?

Explanation

DISCUSSION: The patient has a very low T-type acetabular fracture; however, the head is not congruent under the dome so surgical reduction is necessary. The anterior and posterior columns are displaced and will move independent from each other. The extended iliofemoral is the only approach allowing for visualization and reduction of each column. A combined anterior and posterior approach may also be used. The timing of surgery should be within the first 3 weeks of injury to optimize chances of obtaining an accurate reduction because this is an important factor in determining outcome.
REFERENCES: Letournel E, Judet R (eds): Fractures of the Acetabulum, ed 2.

Berlin, Germany, Springer-Verlag, 1991.
Matta JM: Fractures of the acetabulum: Accuracy of reduction and clinical results in patients managed operatively within three weeks after the injury. J Bone Joint Surg Am

1996;78:1632-1645.

Question 91

A 10-year-old girl who is Risser stage 0 has back deformity associated with neurofibromatosis type 1 (NF1). She has no back pain. Examination shows multiple cafe-au-lait nevi with normal lower extremity neurologic function and reflexes. Standing radiographs of the spine show a short 50-degree right thoracic scoliosis with a kyphotic deformity of 55 degrees (apex T8). A 10-degree progression in scoliosis has occurred during the past 1 year. There is no cervical deformity. MRI shows mild dural ectasia, primarily in the upper lumbar region. Management should consist of Review Topic

Explanation

Scoliotic deformities in patients with NF1 are often dysplastic with short, angular curves. Posterior arthrodesis is made more difficult by the presence of kyphosis and of weak posterior elements caused by dural ectasia. Combined anterior and posterior spinal arthrodesis is generally preferred for progressive dysplastic curves to maximize deformity correction and to decrease the risk of pseudarthrosis. Anterior fusion may also prevent crankshaft phenomenon in young children. Brace treatment is not effective for large, rigid, or dysplastic curves.

Question 92

A 25-year-old man sustained an L1 compression fracture in a fall from his roof. He is neurologically intact and has no other injuries. Radiographs reveal a 25% loss of height anteriorly and 5 degrees of kyphosis at the fracture site. A CT scan reveals no compromise of the posterior column. Management should consist of

Explanation

DISCUSSION: The patient has a stable fracture that can be initially treated with bed rest, followed by bracing and quick mobilization. The outcome is good and surgery is not required. These fractures can be treated nonsurgically if there is less than 50% compression, 15 degrees of angulation, and intact posterior structures.
REFERENCES: Cantor JB, Lebwohl NH, Garvey T, Eismont FJ: Nonoperative management of stable thoracolumbar burst fractures with early ambulation and bracing. Spine 1993;18:971-976.
Rechtine GR II, Cahill D, Chrin AM: Treatment of thoracolumbar trauma: Comparison of complications of operative versus nonoperative treatment. J Spinal Disord 1999;12:406-409.

Question 93

The patient undergoes further testing and it is discovered that the lesion encompasses 70% of the joint. What is the best next treatment option?

Explanation

DISCUSSION
A tarsal coalition is an abnormal connection of 2 or more bones in the foot. Although tarsal coalitions are present at birth, children and adults typically do not show signs of the disorder until early adolescence or later. The exact incidence of the disorder is hard to determine; however, it is caused by a gene mutation that affects cells that produce the tarsal bones. The 2 most common locations for tarsal coalitions are between the calcaneus and the navicular or between the talus and the calcaneus. It is estimated that 1 out of every 100 people may have a tarsal coalition. In 50% of cases, both feet are affected. Tarsal coalitions are rarely discovered until symptoms arise. Symptoms may include stiff and painful feet, a rigid flatfoot, or increased pain or a limp with high-level activities. Upon examination, symptoms may include tenderness in the area of the coalition, loss of motion, rigid flat feet, and arthritic changes of the joint. Imaging studies begin with radiographs. A CT scan can provide bony detail for imaging tarsal coalitions and determining the extent of the coalition and any accompanying degenerative change. MRI can provide details of the soft tissues. Treatment includes nonsurgical care including rest, orthotics, a temporary boot or cast, and injections. Surgical options include resection with interposition of muscle or fatty tissue from another area of the body or fusions when large (exceeding 50% of the joint), more severe coalitions are encountered.
RECOMMENDED READINGS
Lemley F, Berlet G, Hill K, Philbin T, Isaac B, Lee T. Current concepts review: Tarsal coalition. Foot Ankle Int. 2006 Dec;27(12):1163-9. Review. PubMed PMID: 17207452. View Abstract at PubMed
Badgley CE. Coalition of the calcaneus and the navicular. Arch Surg. 1927;15:75-88. Conway JJ, Cowell HR. Tarsal coalition: clinical significance and roentgenographic demonstration. Radiology. 1969 Mar;92(4):799-811. PubMed PMID: 5767760. View Abstract at PubMed
Herzenberg JE, Goldner JL, Martinez S, Silverman PM. Computerized tomography of talocalcaneal tarsal coalition: a clinical and anatomic study. Foot Ankle. 1986 Jun;6(6):273-

Question 94

A 70-year-old golfer has pain in her dominant shoulder. She reports that initially the pain was at night but now she is unable to play. Examination reveals weakness in external rotation and shoulder abduction. Radiographs reveal the humeral head articulating with a thin acromion. Management should consist of

Explanation

DISCUSSION: Chronic rotator cuff tears should be nonsurgically managed initially with a strengthening program. A cortisone injection may reduce inflammation. Surgery is reserved for patients who continue to have pain and lose sleep despite the use of physical therapy. Blood tests for infection or inflammation are nonspecific. Arthroscopy may play a role, but surgical replacement is reserved for advanced cases.
REFERENCES: Bokor DJ, Hawkins RJ, Huckell GH, et al: Results of nonoperative management of full-thickness tears of the rotator cuff. Clin Orthop 1993;294:103-110.
Wirth MA, Basamania C, Rockwood CA Jr: Nonoperative management of full-thickness tears of the rotator cuff. Orthop Clin North Am 1997;28:59-67.

Question 95

Fluoroquinolones work by inhibiting what enzyme?

Explanation

Fluoroquinolones are commonly used antibiotics used to treat orthopaedic infections and are popular because of their equivalency in IV or oral formulations and their gram-positive and gram-negative antibacterial activity. It is part of a larger class of
antibiotics called quinolones that interfere with DNA metabolism. Fluoroquinolones are synthetic derivatives of nalidixic acid. Its mechanism of action involves interfering with the function of DNA gyrase. DNA gyrase ia a type-II topoisomerase, and "unwinds" DNA to allow replication.

Question 96

A 65-year-old man with ankylosing spondylitis has neck pain after falling back over his lawnmower, striking his thoracic spine, and forcing his neck into extension. Examination reveals subtle weakness of the intrinsics and finger flexors at approximately 4+/5. Initial management consists of immobilization in a rigid collar, and placing his head in the anatomic position. Radiographs reveal a subtle extension fracture of the lower cervical spine. Approximately 6 hours after the injury, he reports increasing paresthesias in his upper and lower extremities, and examination now shows his intrinsics are 2/5, finger flexors are 3/5, and his triceps are now weak at 4/5 on manual motor testing. In addition, his lower extremities now show weakness in both dorsal and plantar flexion of the ankle in the range of 4/5. Repeat radiographs appear unchanged. An MRI scan is shown in Figure 2. Management should now consist of

Explanation

DISCUSSION: It is not uncommon for patients with ankylosing spondylitis to sustain extension-type fractures, most typically of the cervicothoracic junction. These fractures can appear nondisplaced or minimally displaced initially, making them difficult to diagnose. Because there is no mobility between vertebrae, fractures tend to occur more like those of a transverse fracture of a long bone. In addition, the vertebral bodies are vascular and their canals are relatively enclosed, making them vulnerable to epidural bleeding. The MRI scan reveals an epidural hematoma located posteriorly on the cord; therefore, the treatment of choice is surgical evacuation and a posterior laminectomy. Because of the intrinsic instability of such fractures at the time of the laminectomy, internal fixation and stabilization with a posterior fusion is warranted. A simple laminectomy will only increase instability, and control is unlikely with halo vest immobilization. An anterior procedure will not effectively treat the problem given the location of the hematoma. Consideration can be given to methylprednisolone and observation; however, this will not eradicate the problem.
REFERENCES: Bohlman HH: Acute fractures and dislocations of the cervical spine. J Bone Joint Surg Am 1979;61:1119-1142.
Weinstein PR, Karpman RR, Gall EP, et al: Spinal cord injury, spine fracture and spinal stenosis in ankylosing spondylitis. J Neurosurg 1982;57:609-616.

Question 97

When comparing the overall outcomes of surgical versus nonsurgical treatment of stable thoracolumbar burst fractures in patients without neurologic injury, 5 years following injury, the principle differences lie in Review Topic

Explanation

When patients are compared at 5 years follow-up, there are no statistically significant differences between the two groups with respect to kyphosis, the degree of retropulsed bone resorption, pain and function levels, or the ability to return to work. Nonsurgical management of stable neurologically intact burst fractures has a very low incidence of complications.

Question 98

When compared with a conventional ultra-high molecular weight polyethylene (UHMWPE) -bearing surface in total hip arthroplasty, a highly cross-linked polyethylene (XLPE) -bearing surface is associated with

Explanation

A 30-year-old patient is indicated for distal femoral osteotomy. This procedure results in survivorship with
A. a functional result for at least 20 years.
B. a functional result that deteriorates within the first 10 years.
C. an eventual conversion to a constrained knee arthroplasty.
D. an eventual need for arthrodesis.
Distal femoral varus osteotomy (DFVO) is intended for patients younger than age 50, more active patients with isolated lateral compartment arthritis and valgus malalignment. Although the knee functional score improves at 1-year follow-up, the function scores significantly deteriorate at 10-year follow-up. At 15-year follow-up, the knee function further declines, resulting in an overall failure rate of 48.5%. DFVO provides longer lasting benefit in patients with better presurgical knee function.
Total knee arthroplasty following DFVO provides improved function and successful outcomes. Standard posterior stabilized components provide satisfactory stability after appropriate ligament balancing without the need for stemmed or highly constrained implants for most patients.

Question 99

Figures 45a and 45b show the radiographs of a 40-year-old woman with rheumatoid arthritis who is unable to straighten her ring and little fingers. Examination reveals that the fingers can be passively corrected, but she is unable to actively maintain the fingers in extension. Management should consist of

Explanation

DISCUSSION: The patient has extensor tendon ruptures at the level of the wrist that are the result of synovitis at the distal radioulnar joint (Vaughn-Jackson syndrome). Extensor indius proprius transfer appropriately matches strength and excursion of the ruptured extensor digiti quinti and extensor digitorum communis tendons. An extensor tenosynovectomy with distal radioulnar joint resection decreases the synovitis, which if left untreated may cause additional tendon ruptures. Radial head resection is used for posterior interosseous nerve compression secondary to radial head synovitis, and in this patient only two fingers are involved, which rules out this diagnosis. Dynamic splinting is not indicated for ruptured tendons. Metacarpophalangeal arthroplasties and imbrication of the sagittal bands are used for metacarpophalangeal arthritis and extensor tendon subluxation. If this was the problem, the patient should be able to maintain the fingers in extension after they are passively extended. Total wrist arthrodesis prevents the tenodesis effect, thus limiting effective tendon excursion and making the proposed transfer less effective.
REFERENCES: Feldon P, Terrono AL, Nalebuff EA, et al: Rheumatoid arthritis and other connective tissue diseases: Tendon ruptures, in Green DP, Hotchkiss RN, Pederson WC (eds): Green’s Operative Hand Surgery, ed 4. New York, NY, Churchill Livingstone, 1999,

pp 1669-1684.
Moore JR, Weiland AJ, Valdata L: Tendon ruptures in the rheumatoid hand: Analysis of treatment and functional results in 60 patients. J Hand Surg Am 1987;12:9-14.
Leslie BM: Rheumatoid extensor tendon ruptures. Hand Clin 1989;5:191-202.

Question 100

A 57-year-old woman experiences pain 1 year after total knee arthroplasty (TKA). She reports sharp anterior pain and a painful catching sensation that is aggravated by rising from a chair or climbing stairs. Physical examination reveals a mild effusion and a range of motion of 2° to 130°, with patellar crepitus. The symptoms are reproduced by resisted knee extension. Radiographs show a well-aligned posterior-stabilized TKA without evidence of component loosening. What is the most likely cause of this patient's pain?

Explanation

DISCUSSION:
Patellar clunk syndrome is caused by the development of a fibrous nodule on the posterior aspect of the quadriceps tendon at its insertion into the patella. It causes a painful catching sensation when the extensor mechanism traverses over the trochlear notch as the knee extends from 45° of flexion to 30° from full extension. It characteristically occurs in posterior stabilized total knee arthroplasties and appears to be related to femoral component design. The syndrome can usually be prevented by excising the residual synovial fold just proximal to the patella. Flexion gap instability can also cause a painful total knee arthroplasty but is less common in posterior stabilized implants. Femoral component malrotation can cause pain attributable to a flexion gap imbalance or patellar tracking problems. Polyethylene wear would be unlikely after just 1 year. Patellar clunk syndrome can usually be addressed successfully with arthroscopic synovectomy. Recurrence is uncommon. Physical therapy may help to strengthen the quadriceps following synovectomy but would not resolve the clunk syndrome symptoms. Femoral or tibial insert revision is not indicated if patellar clunk syndrome is the only problem resulting in a painful
total knee arthroplasty.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

Traumatic mydriasis
Detached retina
Dislocated lens
Corneal abrasion
Traumatic hyphema

Correct Answer: Traumatic mydriasis

Explanation:

Question 2:

Flexion-distraction injuries of the thoracolumbar spine are most frequently associated with injury to what organ system?

Options:

Neurologic
Pulmonary
Gastrointestinal
Vascular
Lymphatic

Correct Answer: Gastrointestinal

Explanation:

Question 3:

Options:

Male gender
Diaphyseal location
Comminuted displaced fracture
Young age
Associated injuries

Correct Answer: Comminuted displaced fracture

Explanation:

DISCUSSION: The patient has a displaced comminuted clavicle middle one third fracture from a high-energy mechanism. Recent literature on high-energy clavicular fractures suggests a higher rate of nonunion than previously reported. A nonunion rate of 30% has been reported by Hill and associates when the fracture fragments are displaced more than 1.5 cm. In addition, several patients had neurologic symptoms related to the injury. Robinson and associates reported an increased risk of nonunion in women, elderly patients, comminuted fractures, and injuries with a lack of cortical contact.
REFERENCES: Hill JM, McGuire MH, Crosby LA: Closed treatment of displaced middle-third fractures of the clavicle gives poor results. J Bone Joint Surg Br 1997;79:537-539.
Wick M, Muller EJ, Kollig E: Midshaft fractures of the clavicle with a shortening of more than
2 cm predispose to nonunion. Arch Orthop Trauma Surg 2001;121:207-211.
Robinson CM, Court-Brown CM, McQueen MM, et al: Estimating the risk of nonunion following nonoperative treatment of a clavicular fracture. J Bone Joint Surg Am
2004;86:1359-1365.

Question 4:

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 5:

Options:

needle biopsy of the distal femur.
open reduction and internal fixation with a locking plate.
closed reduction and fixation with a reamed antegrade locking intramedullary nail.
referral to an orthopaedic oncologist for staging studies, biopsy, and definitive management.
IV antibiotics for 6 weeks.

Correct Answer: referral to an orthopaedic oncologist for staging studies, biopsy, and definitive management.

Explanation:

DISCUSSION: The radiograph shows a pathologic fracture through a destructive lesion of the distal femur metaphysis with osteolytic and osteoblastic features. The lateral cortex is destroyed, and there is periosteal new bone formation. These findings are consistent with malignancy, most likely an osteogenic sarcoma. Patients with suspected malignant tumors are best managed by surgeons with specific expertise in orthopaedic oncology. The biopsy of a malignant lesion should be deferred to the surgeon who is capable of definitive management of the patient.
REFERENCES: Enneking W: Principles of musculoskeletal oncologic surgery, in Evarts C (ed): Surgery of the Musculoskeletal System. New York, NY, Churchill Livingston, 1990.
Herring JA: General principles of tumor management, in Herring JA (ed): Tachdjian’s Pediatric Orthopaedics, from the Texas Scottish Rite Hospital for Children, ed 3. Philadelphia, PA, WB Saunders, 2002, pp 1897-1900.

Question 6:

Options:

Arthrogryposis
Melorheostosis
Focal scleroderma
Calcaneal osteomyelitis
Klippel-Trenaunay-Weber syndrome

Correct Answer: Focal scleroderma

Explanation:

Question 7:

What nerve is most at risk during placement of the anterolateral portal in elbow arthroscopy?

Options:

Median
Ulnar
Radial
Posterior interosseous
Anterior interosseous

Correct Answer: Radial

Explanation:

Question 8:

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 9:

Figures 38a and 38b

Options:

Open reduction and internal fixation (ORIF)
Walking boot and weight bearing as tolerated until pain subsides
Nonweight-bearing cast for 6 weeks
Physical therapy
Closed reduction and weight bearing as tolerated
Closed reduction and percutaneous fixation
Figures 38a and 38b

Correct Answer: Open reduction and internal fixation (ORIF)

Explanation:

DISCUSSION
Inversion of the ankle can cause various injuries about the foot and ankle, all via the same mechanism. Fifth metatarsal base avulsion (Figure 35) fractures can be treated with use of a walking boot until pain subsides. Jones fractures (Figure 36) can be treated with surgical or nonsurgical treatment, although young, active patients are perhaps better treated with ORIF, which can decrease disability time. Treatment of an anterior process calcaneus fracture (Figure 37) is similar to that for a fifth metatarsal base avulsion fracture. Figures 38a and 38b show a calcaneal fracture-dislocation, which necessitates ORIF.
RECOMMENDED READINGS
Schepers T, Backes M, Schep NW, Carel Goslings J, Luitse JS. Functional outcome following a locked fracture-dislocation of the calcaneus. Int Orthop. 2013 Sep;37(9):1833-8. PubMed PMID: 23959223.
View Abstract at PubMed
Polzer H, Polzer S, Mutschler W, Prall WC. Acute fractures to the proximal fifth metatarsal bone: development of classification and treatment recommendations based on the current evidence. Injury. 2012 Oct;43(10):1626-32. doi: 10.1016/j.injury.2012.03.010. Epub 2012 Mar 30. Review. PubMed PMID: 22465516.
View Abstract at PubMed
Roche AJ, Calder JD. Treatment and return to sport following a Jones fracture of the fifth metatarsal: a systematic review. Knee Surg Sports Traumatol Arthrosc. 2013 Jun;21(6):1307-15. doi: 10.1007/s00167-012-2138-8. Epub 2012 Sep 6. Review. PubMed PMID: 22956165.
View Abstract at
PubMed
Berkowitz MJ, Kim DH. Process and tubercle fractures of the hindfoot. J Am Acad Orthop Surg. 2005 Dec;13(8):492-502. Review. PubMed PMID: 16330511.
View Abstract at PubMed

Question 10:

Figure 48 shows an MRI scan of the knee. The arrow is pointing to what structure?

Options:

Iliotibial bone
Popliteal tendon
Biceps femoris
Peroneal nerve
Adductor longus

Correct Answer: Biceps femoris

Explanation:

Question 11:

Which modality has the broadest application for the reduction of postsurgical transfusion?

Options:

Regional anesthesia
Tranexamic acid (TXA) administration
Reduced transfusion trigger
Hypotensive anesthesia

Correct Answer: Tranexamic acid (TXA) administration

Explanation:

Question 12:

Options:

Continue to observe with repeat radiographs in 6 months B. Fluoroscopic-guided iliopsoas tendon cortisone injection C. Hip aspiration
Serum cobalt and chromium levels and metal-reduction MRI scan

Correct Answer: Continue to observe with repeat radiographs in 6 months B. Fluoroscopic-guided iliopsoas tendon cortisone injection C. Hip aspiration

Explanation:

Question 13:

A 28-year-old man sustained a fracture-dislocation of T8 in a motor vehicle accident 1 week ago. The injury resulted in complete paraplegia. Management should consist of

Options:

mobilization in a kinetic therapy bed for 8 weeks.
initiation of a steroid protocol.
immediate laminectomy of T7, T8, and T9.
application of a total contact orthosis.
open reduction and posterior segmental stabilization and grafting.

Correct Answer: open reduction and posterior segmental stabilization and grafting.

Explanation:

Question 14:

Options:

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

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

Explanation:

Question 15:

-The center of rotation of the knee can be best described as

Options:

remaining fixed during flexion.
moving posterior as flexion increases.
shifting forward and then back with flexion.
shifting posterior on the lateral side with flexion.
sliding forward on the medial side with increasing flexion.

Correct Answer: shifting posterior on the lateral side with flexion.

Question 16:

What is the most likely contributory factor to this patient's problem?

Options:

Throwing curveballs
Year-round throwing
Poor calcium intake
Shoulder laxity

Correct Answer: Year-round throwing

Explanation:

Question 17:

Options:

Impingement injection test
Lift-off test
Weakness with “empty-can” abduction test
Load-and-sift maneuver
MRI with contrast

Correct Answer: Lift-off test

Explanation:

Question 18:

Figure 1 is the radiograph of a 22-year-old man who underwent an open reduction and pinning of a perilunate dislocation 10 weeks ago. The hardware has been removed. What is the best next step?

Options:

Observation
Vascularized bone grafting to the lunate
Core decompression of the radius and ulna
Immobilization

Correct Answer: Observation

Explanation:

Question 19:

Options:

Pain during sitting; flexion abduction and external rotation of the hip
Groin pain; pain with internal rotation and adduction while supine with the hip and knee flexed 90°
Clicking; abductor lurch
Buttock pain; pain with hip extension, adduction, and external rotation while prone

Correct Answer: Groin pain; pain with internal rotation and adduction while supine with the hip and knee flexed 90°

Explanation:

Question 20:

A Trendelenburg gait is most likely to be seen in association with

Options:

a central disk herniation at L3-L4.
an ipsilateral paracentral disk herniation at L3-L4.
an ipsilateral paracentral disk herniation at L4-L5.
an ipsilateral paracentral disk herniation at L5-S1.
an ipsilateral far lateral disk herniation at L4-L5.

Correct Answer: an ipsilateral paracentral disk herniation at L4-L5.

Explanation:

Question 21:

A 23-year-old woman has had vague left knee pain for the past 6 months. A radiograph and CT scan are shown in Figures 50a and 50b. What is the most likely diagnosis?

Options:

Myositis ossificans
Osteochondroma
Parosteal osteosarcoma
Dedifferentiated chondrosarcoma
Tumoral calcinosis

Correct Answer: Parosteal osteosarcoma

Explanation:

Question 22:

A 5-year-old boy has had midfoot pain with activity for the past 3 months. He has no pain at rest. Radiographs are shown in Figures 29a and 29b. Management should consist of

Options:

a vascularized pedicle bone graft.
a short leg walking cast.
a custom-molded orthotic.
surgical debridement followed by antibiotics.
a bone stimulator.

Correct Answer: a short leg walking cast.

Explanation:

Question 23:

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:

Question 24:

Options:

Subtrochanteric osteotomy with femoral shortening
An offset femoral component
A lateralized liner
Extended trochanteric osteotomy

Correct Answer: Subtrochanteric osteotomy with femoral shortening

Explanation:

Question 25:

- Following closed reduction for the injury shown in Figures 69a and 69b, treatment should consist of

Options:

repair or reconstruction of the medial collateral ligament
repair or reconstruction of the medial
and lateral collateral ligaments
immobilization for 5 days or less
immobilization for 14 days
immobilization for 25 days

Correct Answer: and lateral collateral ligaments

Explanation:

Question 26:

BMP is FDA approved for well-defined medical conditions in limited patient populations. In which of the following clinical scenarios is use of rhBMP-2 FDA approved?

Options:

In a 32-year-old male with an acute, open tibial shaft fracture treated with minimally-invasive locked plating 8 days from the initial injury
In the lumbar spine in a 45-year-old female undergoing posterior decompression and instrumented posterolateral fusion from L4 to S1
In the cervical spine in a 56-year-old female undergoing anterior cervical discectomy and fusion of C5-C6
In the lumbar spine in a 52-year-old male undergoing L5-S1 anterior lumbar interbody fusion for degenerative disc disease and spinal stenosis
In the cervical spine in a 60-year-old male undergoing posterior decompression and posterior instrumented fusion of C3-C7

Correct Answer: In a 32-year-old male with an acute, open tibial shaft fracture treated with minimally-invasive locked plating 8 days from the initial injury

Explanation:

Question 27:

A 12-year-old girl has scoliosis at T5-T10 that measures 62°. A clinical photograph of the axilla is shown in Figure 56. Management should consist of

Options:

a thoracolumbosacral orthosis.
in situ posterior spinal fusion.
posterior spinal fusion with segmental instrumentation.
anterior spinal fusion with instrumentation.
anterior and posterior spinal fusion with posterior segmental instrumentation.

Correct Answer: anterior and posterior spinal fusion with posterior segmental instrumentation.

Explanation:

Question 28:

Compared with percutaneous pinning with Kirschner wires (K-wires), the treatment of metacarpal neck fractures with cannulated intramedullary screws is associated with

Options:

increased rates of soft-tissue infection.
greater initial construct stiffness and peak load until failure.
a slower return of digital range of motion.
an earlier time to bony union.

Correct Answer: greater initial construct stiffness and peak load until failure.

Explanation:

EXPLANATION:
In a biomechanical study, headless compression screws showed superior load to failure, higher three-point bending strength, and greater strength in axial loading compared with percutaneous K-wire fixation for metacarpal neck fractures. Headless compression screws provide greater initial stability to allow earlier motion in the postoperative period. No data comparing infection rates between the two methods of fixation are available; however, it is assumed that K-wires placed outside of the skin would have increased
rates of infection. Neither fixation method would increase the time to healing.

Question 29:

Options:

referral to a plastic surgeon to remove the hairy patch.
MRI of the entire spine.
physical therapy and repeat evaluation and radiographs in 1 year.
anterior and posterior fusion of the anomalous regions of the spine to prevent deformity.
voiding cystourethrography.

Correct Answer: MRI of the entire spine.

Explanation:

DISCUSSION: Congenital anomalies of the spine, including failure of formation and failure of segmentation, are associated with other anomalies in other organ systems that develop at the same time. These include anomalies in the genitourinary system, cardiac anomalies, Sprengel’s deformity, radial hypoplasia, and gastrointestinal anomalies including imperforate anus and trachealesophageal fistula. Spinal dysraphism is the most common associated abnormality. McMaster found an 18% incidence before the common use of MRI. Bradford and associates reported on 16 of 42 patients with congenital spinal anomalies and spinal dysraphism using MRI. Neural axis lesions may be associated with visible midline abnormalities such as a hairy patch or nevus. The child has already had a cardiac and renal work-up, and based on the findings of the hairy patch and congenital vertebral anomalies, MRI of the entire spine is prudent at this time. Spinal fusion is indicated for progressive congenital scoliosis or kyphosis. Physical therapy does not affect the natural history of congenital scoliosis.
REFERENCES: McMaster MJ: Occult intraspinal anomalies and congenital scoliosis. J Bone Joint Surg Am 1984;66:588-601.
Bradford DS, Heithoff KB, Cohen M: Intraspinal abnormalities and congenital spine deformities: A radiographic and MRI study. J Pediatr Orthop 1991;11:36-41.
McMaster MJ, David CV: Hemivertebrae as a cause of scoliosis: A study of 104 patients.
J Bone Joint Surg Br 1986;68:588-595.

Question 30:

Options:

Odds ratio
Incidence rates
Prevalence rates
Relative risk
Confidence intervals

Correct Answer: Relative risk

Explanation:

Question 31:

Options:

chevron osteotomy of the fifth metatarsal head, with capsular plication and release of the medial collateral ligament.
metatarsal head excision with soft-tissue interposition.
“floating” distal oblique osteotomy.
oblique biplanar diaphyseal fifth metatarsal osteotomy.
proximal crescentic osteotomy of the fifth metatarsal base.

Correct Answer: oblique biplanar diaphyseal fifth metatarsal osteotomy.

Explanation:

Question 32:

Options:

Revision using a proximal femoral replacement prosthesis
Revision using a diaphyseal engaging femoral prosthesis along with cerclage fixation
Open reduction internal fixation using a locking plate with strut graft
Protected weight bearing with abduction bracing

Correct Answer: Revision using a diaphyseal engaging femoral prosthesis along with cerclage fixation

Explanation:

Question 33:

Options:

Escherichia coli
Streptococcus viridans
Oxalophagus oxalicus
Proprionobacter acnes
Enterococcus faecalis

Correct Answer: Proprionobacter acnes

Explanation:

DISCUSSION: Proprionobacter acnes has been a leading cause of indolent shoulder infections. During shoulder arthroscopy, the arthroscopic fluid may actually dilute the shoulder preparation and lead to a higher rate of infection during subsequent mini-open rotator cuff repair surgery. The remaining bacteria listed are rarely associated with shoulder infections after arthroscopy.
REFERENCES: Herrera MF, Bauer G, Reynolds F, et al: Infection after mini-open rotator cuff repair. J Shoulder Elbow Surg 2002;11:605-608.
Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 551-557.

Question 34:

Options:

ultrasonic stimulation for 3 months.
removal of the nail and plate fixation.
continued observation.
removal of the distal locking screws to dynamize the nail.
exchange reamed nailing with bone graft.

Correct Answer: exchange reamed nailing with bone graft.

Explanation:

Question 35:

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

Options:

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

Correct Answer: Anterior and inferior

Explanation:

Question 36:

Options:

Pitchers throwing less fastballs and more changeups
Evaluate the pitchers elbows for ulnar collateral ligament acute ruptures.
Increasing the weight training for the deltoid and latissimus dorsi muscles
Focused stretches and therapies that address posterior capsular tightness
Firing the general manager for finding pitchers that "lose their stuff"

Correct Answer: Pitchers throwing less fastballs and more changeups

Explanation:

Question 37:

Figures 12a through 12e show the radiograph, MRI scans, and biopsy specimens of a 17-year-old boy. What is the most likely diagnosis?

Options:

Giant cell tumor
Chondroblastoma
Clear cell chondrosarcoma
Osteosarcoma
Tuberculous septic arthritis

Correct Answer: Chondroblastoma

Explanation:

DISCUSSION: The images show an epiphyseal lesion. The MRI scan shows extensive bone edema surrounding the lesion, consistent with chondroblastoma. Histology shows polygonal chondroblasts in a cobblestone-like pattern and areas of calcification consistent with chondroblastoma. Although some giant cells are seen, the age of the patient and the polygonal chondroblasts differentiate this lesion from giant cell tumor. Clear cell chondrosarcoma is an epiphyseal lesion that occurs in an older population, and the cells have clear cytoplasm. This lesion is not producing bone on imaging or histologic specimen, eliminating osteosarcoma. Tuberculous septic arthritis can be an epiphyseal lesion, but granulomas would be seen on histology.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Campanacci M: Bone and Soft Tissue Tumors, ed 2.
New York, NY, Springer-Verlag, 1999,
pp 247-263.

Question 38:

Options:

Less than 10%
20% to 25%
50% to 60%
75% to 80%
Greater than 95%

Correct Answer: 50% to 60%

Explanation:

Question 39:

A total shoulder arthroplasty (TSA) would be the most appropriate treatment in which of the following arthritic patients? Review Topic

Options:

A 75-year-old female with a longstanding history of brachial plexus palsy
A 63-year-old male with a 6 month history of shoulder pain and inability to abduct past 30 degrees
A 67-year-old female with chronic shoulder pain and evidence of significant proximal migration of the humerus on x-ray
A 70-year-old female with severe shoulder pain and radiographic evidence of glenoid erosion to the coracoid process
A 72-year-old male who is 9 months status post right TKA for OA with debilitating shoulder pain and an MRI demonstrating an intact rotator cuff

Correct Answer: A 75-year-old female with a longstanding history of brachial plexus palsy

Explanation:

Question 40:

What structure is located at the tip of the arrow in Figure 18? Review Topic

Options:

Left L3 nerve root
Right L3 nerve root
Right L4 segmental artery
Right L4 nerve root
Left lateral disk herniation

Correct Answer: Right L3 nerve root

Explanation:

The structure shown is the exiting nerve root at the L3-4 disk, which is the right L3 root.

Question 41:

- Which of the following shoulder girdle muscles is most active during forward flexion?

Options:

Biceps
Trapezius
Infraspinatus
Pectoralis major
Serratus anterior

Correct Answer: Serratus anterior

Explanation:

Question 42:

Options:

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

Correct Answer: Discoid lateral meniscus

Explanation:

Question 43:

The Coleman block test is used to test for Review Topic

Options:

flexibility of the forefoot.
flexibility of the hindfoot.
valgus deformity of the hindfoot.
tightness of tendo Achilles.

Correct Answer: flexibility of the hindfoot.

Explanation:

Question 44:

Options:

pain out of proportion to injury
pale appearance of the foot
loss of the ability to move the toes
decreased sensation in the foot
decreased pulses in the foot

Correct Answer: pain out of proportion to injury

Explanation:

Question 45:

Options:

continued use of an ankle-foot orthosis.
direct repair of the Achilles tendon.
V-Y repair of the Achilles tendon.
transfer of the plantaris tendon.
Achilles tendon turndown with flexor hallucis longus tendon transfer.

Correct Answer: Achilles tendon turndown with flexor hallucis longus tendon transfer.

Explanation:

Question 46:

Options:

Viscosupplementation of the right hip
Hip arthroscopy with labral repair
Periacetabular osteotomy
Total hip arthroplasty

Correct Answer: Periacetabular osteotomy

Explanation:

Question 47:

Options:

Epidural hematoma
Herniated disk
Tumor
Extruded epidural bony fragment
Abscess

Correct Answer: Epidural hematoma

Explanation:

Question 48:

Options:

immediate posterior surgical reduction and stabilization.
immediate anterior diskectomy and fusion.
MRI.
reduction in Gardner-Wells tongs with serial traction.
rigid collar immobilization until spinal shock resolves.

Correct Answer: reduction in Gardner-Wells tongs with serial traction.

Explanation:

DISCUSSION: Surgical open reduction may increase the neurologic deficit if a disk herniation exists. Evidence from animal studies suggests that rapid decompression of the spinal cord may improve recovery. Serially increasing traction weight to reduce the dislocation has been shown to be safe when used in patients who are awake. Indications for MRI include patients who are unable to cooperate with serial examinations, the need for open reduction, and progression of deficit during awake reduction.
REFERENCES: Delamarter RB, Sherman J, Carr JB: Pathophysiology of spinal cord injury: Recovery after immediate and delayed decompression. J Bone Joint Surg Am
1995;77:1042-1049.
Star AM, Jones AA, Cotler JM, Balderston RA, Sinha R: Immediate closed reduction of cervical spine dislocations using traction. Spine 1990;15:1068-1072.
Eismont FJ, Arena MJ, Green BA: Extrusion of an intervertebral disc associated with traumatic subluxation or dislocation of cervical facets: Case report. J Bone Joint Surg Am
1991;73:1555-1560.

Question 49:

Options:

External rotation of the femoral component
Overstuffing of the patellofemoral joint
Less than 12 mm of bony patella remaining after resection
Lateral retinacular release
Use of a cemented patellar component

Correct Answer: Less than 12 mm of bony patella remaining after resection

Explanation:

Question 50:

Long bone fracture repair following intramedullary stabilization occurs primarily through which of the following healing mechanisms?

Options:

Haversian remodeling
endosteal ossification only
Intramembranous ossification only
Endochondral ossification only
Intramembranous and endochondral ossification

Correct Answer: Intramembranous and endochondral ossification

Explanation:

Question 51:

Options:

Propionibacterium acnes
Staphylococcus aureus
Group B streptococcus
Neisseria gonorrhea
Enterococcus coli

Correct Answer: Enterococcus coli

Explanation:

This patient has sternoclavicular joint septic arthritis with gram positive organisms. Although there is an increased incidence of Pseudomonas aeruginosa infection in IV drug users, S. aureus is still the most common organism.
Ross et al states "Staphylococcus aureus is now the major cause of
sternoclavicular septic arthritis in intravenous drug users. Pseudomonas aeruginosa infection in injection drug users declined dramatically with the end of an epidemic of pentazocine abuse in the 1980s."
The referenced article by Goldin et al is from the New England Journal of Medicine reports that all of their cases of SC joint septic arthritis were in intravenous drug abusers and that P. aeruginosa grew out of 3 patients and S. aureus grew out of 1 patient.
A more recent article by Abu Arab et al reported that Staph aureus was most common even in IV drug users. The review article by Higginbotham and Kuhn note that risk factors for SC joint septic arthritis include hemodialysis, immunocompromise, alcoholism, and HIV. Neisseria gonorrhoeae, fungal, and candida present in HIV patients.
Treatment is I&D and appropriate antibiotics, although aspiration and abx have shown some success too. CT and MRI are useful in diagnosis, and open biopsy or aspiration is recommended for definitive diagnosis.
A 30-year-old man presents with a distal third tibia fracture that has healed in 25 degrees of varus alignment. The patient is at greatest risk of developing which of the following conditions as a result of this malunion?
Degenerative lumbar spine changes
Ipsilateral ankle pain and stiffness
Ipsilateral hip joint degenerative changes
Contralateral hip joint degenerative changes
Ipsilateral medial knee degenerative changes
Correct answer: 2
A significant malunion of the distal tibia has important consequences for patient outcome, including pain, gait changes, and cosmesis.
The first referenced article by Milner et al looked at long-term outcomes of tibial malunions and noted that varus malunion led to increased ankle/subtalar stiffness and pain regardless of the amount of radiographic degenerative changes.
The second referenced article by Puno et al reinforced the concept of decreased functional outcomes of the ankle with tibial malunions, and noted
that other lower extremity joints (ipsilateral and contralateral) do not have increased rates of degeneration from such a malunion.
A 33-year-old man sustains a femur fracture in a motorcycle accident. AP and lateral radiographs are provided in Figure A. Prior to surgery, a CT scan of the knee is ordered for preoperative planning. Which of the following additional findings is most likely to be discovered?
Tibial eminence fracture
Sagittal plane fracture of the medial femoral condyle
Schatzker I tibia plateau fracture
Coronal plane fracture of the lateral femoral condyle
Axial plane fracture through the medial femoral condyle
Correct answer: 4
The "Hoffa fracture" is a coronal plane fracture of the femoral condyle that is often missed on plain radiographs of supracondylar and intercondylar femur fractures. It involves the lateral condyle more frequently than the medial.
Identification is important as it may impact operative planning and likely require screw fixation in the anteroposterior plane.
Nork et al. reviewed 202 supracondylar-intercondylar distal femoral fractures and found a 38% prevalence of associated coronal plane fractures. The authors recommend CT scan imaging of all supracondylar and intercondylar fractures.
Ostermann et al reported on 24 unicondylar fractures of the distal femur treated with open reduction internal fixation with a screw construct. Twenty-
three patients acheived satisfactory results at 5 year follow-up. Illustrations A and B are another example of a supracondylar femur fracture with an associated Hoffa fracture identified on CT scan.
A 35-year-old woman presents with an elbow injury which includes a coronoid fracture involving more than 50%, a comminuted
radial head fracture, and an elbow dislocation. What is the most appropriate treatment?
closed reduction and early range of motion
radial head resection and lateral collateral ligament reconstruction
radial head resection and coronoid open reduction internal fixation
radial head arthroplasty and coronoid open reduction internal fixation
radial head arthroplasty, coronoid open reduction internal fixation, and lateral collateral ligament repair
A terrible triad of the elbow includes dislocation of the elbow with associated fractures of the radial head and the coronoid process. Ring et al. stressed that these injuries are prone to complications and advised against resection of the radial head due to instability, and instead recommended a radial head replacement if too comminuted for ORIF. Coronoid fractures compromise elbow stability as well and require open reduction and internal fixation as with the lateral collateral ligament. McKee et al. showed stable elbows in 34/36 with mean Mayo elbow score of 88 when the standard protocol of coronoid ORIF, radial head repair/replacement, and LCL repair were employed.
The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:
perpendicular to the medial clear space
parallel to the talar body
between the tips of the malleoli
perpendicular to the shaft of the fibular
parallel to the subtalar joint
Correct answer: 3
The talocrural angle is formed by the intersection of a line perpendicular to the plafond with a line drawn between the malleoli (average = 83+/-4deg). When the lateral malleolus is shortened secondary to fracture, this can lead to increased talocrural angle. This malunion leads to lateral tilt of the talus.
Phillips et al looked at 138 patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture. Although the conclusions were limited due to poor follow up, they found the difference in the talocrural angle between the injured and normal sides was a statistically significant radiographic indicator of a good prognosis.
Pettrone et al looked at a series of 146 displaced ankle fractures, and the effect of open or closed treatment, and internal fixation of one or both malleoli. They found open reduction proved superior to closed reduction, and in bimalleolar fractures open reduction of both malleoli was better than fixing only the medial side.
Illustrations A and B are demonstrations of the talocrural angle.
A 33-year-old male sustains the injury shown in Figure A. He is initially treated with a spanning external fixator followed by definitive open reduction internal fixation of the tibia and fibula. His wounds healed without infection or other complications. Two years following surgery, which of the following parameters will most likely predict a poor clinical outcome and inability to return to work?
Joint line restoration
Degree of fracture displacement
Time before definitive ORIF
Open fracture
Lower level of education
Correct answer: 5
Lower level of education is the parameter that correlated most closely with a poor clinical outcome and inability to return to work.
To determine what fracture- and patient-specific variables affect outcome, Williams et al evaluated 29 patients with 32 tibial plafond fractures at a minimum of 2 years from the time of injury. Outcome was assessed by four independent measures: a radiographic arthrosis score, a subjective ankle score, the Short Form-36 (SF-36), and the patient’s ability to return to work. The four outcome measures did not correlate with each other. Radiographic arthrosis was predicted best by severity of injury and accuracy of reduction. However, these variables did not show any significant relationship to the clinical ankle score, the SF-36, or return to work. These outcome measures were more influenced by patient-specific socioeconomic factors. Higher ankle
scores were seen in patients with college degrees and lower scores were seen in patients with a work-related injury. The ability to return to work was affected by the patient’s level of education.
Pollak et al performed a retrospective cohort analysis of pilon fractures. Patient, injury, and treatment characteristics were recorded. The primary outcomes that were measured included general health, walking ability, limitation of range of motion, pain, and stair-climbing ability. A secondary outcome measure was employment status. Multivariate analyses revealed that presence of two or more comorbidities, being married, having an annual personal income of less than $25,000, not having attained a high-school diploma, and having been treated with external fixation with or without limited internal fixation were significantly related to poorer results as reflected by at least two of the five primary outcome measures.
What is the most appropriate treatment for a 17-year-old boy who sustained a gunshot wound to his forearm from a handgun with a muzzle-velocity of 1000 feet/second if he is neurovascularly intact and radiographs reveal no fracture?
Irrigation and local wound care in the emergency department
Emergent irrigation and debridement in the operating room with vacuum-assisted wound closure
Emergent irrigation and debridement in the operating room with 7 days of intravenous antibiotics
Wound closure in the emergency department with follow-up wound check in 1 week
Exploration and removal of all bullet fragments in the emergency department and 10 day course of oral antibiotics
The question refers to appropriate management of a gunshot wound to the forearm. The first question that must be answered when evaluating gunshot injuries is whether the gunshot is low velocity or high velocity. Low-velocity wounds are less severe, are more common in the civilian population, and are typically attributed to bullets with muzzle velocities below 1,000 to 2,000 feet per second. Tissue damage is usually more substantial with higher-velocity (greater than 2,000 to 3,000 fps) military and hunting weapons. In this question, a muzzle velocity of 1,000 ft/sec is provided. Low velocity injuries with stable, non-operative fractures can be treated with local wound care.
The two referenced articles offer guidance for treating low-velocity gunshot injuries with stable, non-operative fracture patterns. The first article by Geissler et al is a retrospective study comparing 25 patients that prospectively received local irrigation and debridement, tetanus prophylaxis and a long acting cephalosporin intramuscularly to a random retrospective sample of 25 patients with similar ballistic-induced fractures and wounds managed by local debridement and 48h of intravenous antibiotics. One infection occurred in each group, requiring further therapy. It was concluded that patients with low-velocity gunshot induced fractures can be managed without the use of short-term intravenous antibiotics with no increased risk of infection.
In the second study, Dickey et al evaluated the efficacy of an outpatient management protocol for patients with a gunshot-induced fracture with a stable, non-operative configuration. 41 patients with a grade I or II open, nonoperative fracture secondary to a low-velocity bullet were treated with 1gm of cefazolin administered in the emergency room and a 7-day course of oral cephalexin. No patient developed a deep infection. Thus, local I&D, tetanus, and oral antibiotics for 2-3 days is adequate for low velocity gunshot wounds.
Which clinical sign is the most sensitive for the diagnosis of compartment syndrome in a child with a supracondylar humerus fracture?
pulselessness
pallor
paresthesia
paralysis
increasing analgesia requirement
Correct answer: 5
Although pain, pallor, paresthesia, paralysis, and pulselessness are all possible signs and symptoms of compartment syndrome in children with fractures, studies have shown increasing analgesia requirement is more sensitive.
Bae et al reviewed thirty-six cases of compartment syndrome in 33 pediatric patients. Approximately 75% of these patients developed compartment syndrome in the setting of fracture. "They found pain, pallor, paresthesia, paralysis, and pulselessness were relatively unreliable signs and symptoms of compartment syndrome in these children. An increasing analgesia requirement in combination with other clinical signs, was a more sensitive indicator of
compartment syndrome."
Whitesides et al summarizes the diagnosis and treatment of acute compartment syndrome. They emphasize the need for early diagnosis, as "muscles tolerate 4 hours of ischemia well, but by 6 hours the result is uncertain; after 8 hours, the damage is irreversible." They recommend fasciotomy be performed when tissue pressure rises past 20 mm Hg below diastolic pressure.
A 45-year-old man sustains the injury seen in Figures A and B following a motor vehicle accident. Postoperative radiographs are seen in Figures C and D. Which of the following is the most accurate when comparing outcomes between intramedullary nailing (IMN) and open reduction internal fixation (ORIF) for this injury?
Union rates at one year are higher with ORIF
Infection rates are higher with IMN
Functional shoulder outcomes at one year are equivalent with IMN and ORIF
Iatrogenic radial nerve injury rate is higher with ORIF
Shoulder stiffness rates at one year are equivalent with IMN and ORIF
Correct answer: 3
Although shoulder pain and stiffness is increased following IMN compared to ORIF, functional outcome scores at one year have been shown to be equivalent
in both treatment groups.
Diaphyseal humeral shaft fractures outcomes following IMN and ORIF are under further investigation. Diaphyseal humeral shaft fractures have historically been treated with ORIF, however proponents for IMN cite benefits of less periosteal stripping and soft tissue dissection. Recent investigations have shown outcomes with regard to nonunion, infection, re-operation, and nerve palsy appear equivalent between both groups. Rates of shoulder stiffness and shoulder pain have been demonstrated to be higher in IMN compared to ORIF. American Shoulder and Elbow Scores (ASES) have shown no difference at one year post-operatively.
Bhandari et al. performed a meta-anaylsis of 3 prospective randomized trials. They found lower rates of re-operation and shoulder impingement with ORIF of humeral shaft fractures.
Wali et al. performed a prospective randomized study of IMN or ORIF on 50 patients with mid-diaphyseal humeral shaft fractures. They found IMN had shorter operative time, shorter hospital stay, and lower blood loss. They found no difference in union rates, complication, or shoulder functional outcomes scores. They conclude IMN to be an effective option for treating mid-diaphyseal humeral shaft fractures.
Heineman et al. have recently conducted an update on their meta-analysis to include more recent randomized studies. With the inclusion of newer studies the author found a statistically significant increase in total complication rate with the use of IM nailing compared with ORIF. The authors found no significant difference between the two treatment modalities for the secondary outcomes (nonunion, infection, nerve palsy, re-operation).
Figures A and B show a diaphyseal humeral shaft fracture. Figure C and D show postoperative radiographs following intramedullary nailing of a humeral shaft fracture.
Incorrect Answers:
A 25-year-old female presents complaining of progressive anteromedial pain in her left ankle. She underwent operative fixation 5 months prior at an outside hospital. The operative report indicated that, due to anterior fracture blisters, a direct medial incision was utilized, centered over the posterior colliculus of the medial malleolus, without violation of the deltoid ligament. A radiograph and computed tomographic scan of her initial injury are shown in Figures A and B, respectively. On exam, she has well-healed incisions, exhibits no tenderness to palpation over her hardware, but does endorse pain with deep palpation along the anteromedial joint line. Figure C shows an anteroposterior left ankle radiograph taken today. Labs are obtained and reveal a white blood cell count of 9.0 k/uL (reference range 4.5-11.0 k/uL) and a C-reactive protein value of 0.8 mg/dL (<0.9 mg/dL). What is the next best step in managing her problem?
Syndesmotic fixation
Intra-articular corticosteroid injection
Referral to physical therapy
Surgical correction of malunion
Removal of hardware
Correct answer: 4
This patient sustained a supination-adduction (SAD) injury with a vertical shear fracture of her medial malleolus and a fibular avulsion fracture. She sustained a medial plafond articular impaction injury that was not addressed at the time of surgery.
In SAD injuries, supination of the foot is combined with inward rotation at the ankle, adduction of the hindfoot, and inversion of the forefoot. This results in the following sequence of events: 1. Talofibular sprain or distal fibular avulsion (equivalent to Weber A). 2. Vertical medial malleolus fracture as the talus strikes the tibia. Associated injuries may include osteochondral damage to the talus and marginal impaction of the medial plafond. It is important to evaluate the medial plafond for articular impaction. When present, an arthrotomy must be performed, typically utilizing an anteromedial incision, with direct visualization of the articular surface to restore the joint line appropriately.
Weber et al. provided a review article on corrective osteotomies for malleolar fracture malunions. They stress that malunions can lead to ankle instability, abnormal load transfer, and post-traumatic arthritis. They conclude that corrective osteotomies that restore anatomical alignment show good results in long-term follow-up.
Perera et al. provided additional commentary on the surgical reconstruction of malunited ankle fractures. The authors emphasize the link between malunion and poor outcomes. They state that successful salvage procedures involve a clear understanding of the deformity, careful preoperative planning, and a solid understanding of reconstructive techniques. They provide several instructive case examples in their review.
McConnell et al. provided a discussion on SAD ankle fractures at their institution and emphasized the importance of recognizing marginal impaction of the tibial plafond when treating these injuries. Of 800 ankle fractures identified over a 5-year period, 44 were SAD injuries, 19 of the 44 displayed a vertical shear fracture of the medial malleolus, and 8 of the 19 demonstrated marginal impaction of the tibial plafond. These 8 impaction injuries were treated with open reduction internal fixation with elevation of the articular impaction; all had good to excellent outcomes without arthritic changes at last
follow-up.
Figure A is an anteroposterior left ankle radiograph demonstrating a SAD injury with a vertical shear fracture of the medial malleolus, a fibular avulsion fracture, and articular impaction of the medial tibial plafond. Figure B is a coronal CT demonstrating articular impaction of the medial plafond. Illustration A is an intra-operative photograph with the medial malleolus retracted allowing inspection of the articular surface; mild anteromedial plafond impaction is present.
Incorrect Answers:
A 90-year-old female slips and falls at home. She is a community ambulator and has no medical problems. She reports right hip pain at this time. Injury radiographs are shown in Figures A & B. Delay of more than 48 hours may result in:
Increased intraoperative time
Increased 30-day mortality
No impact on the rate of postoperative pneumonia
Higher rates of blood transfusion
Increased risk of post-operative infection
Correct answer: 2
Figures A & B demonstrate a right, unstable intertrochanteric femur fracture. Surgical stabilization within 48 hours improves short-term and 30-day mortality.
Hip fractures are common and mortality rates vary. In the elderly, mortality rates may reach 10% at 1-month, 20% at 4-months, and 30% at 1-year. Time to surgery has found to be a decisive factor. A pre-operative delay may lead to an increase in mortality and adversely influence other clinical outcomes.
Clinical guidelines recommend immediate operative stabilization, given the patient is medically fit for surgery.
Nyholm et al. performed a retrospective study of the Danish Fracture Database to investigate whether a surgical delay increases 30-day and 90-day mortality rates for patients with proximal femoral fractures. The 30-day and 90-day mortalities were 10.8% and 17.4%, respectively. The risk of 30-day mortality increased with increasing time intervals of more than 12 hours, 24 hours, and more than 48 hours. 90-day mortality increased with a surgical delay of more than 24 hours. They conclude that rapid surgical treatment should be performed by attending orthopaedic surgeons.
Moja et al. performed a meta-analysis and meta-regression to assess the relationship between surgical delay and mortality in elderly patients with a hip fracture. They analyzed 35 independent studies with 191,873 patients and 34,448 deaths. The majority of studies had a cut-off of 48 hours. They report that early hip surgery was associated with a lower risk of death and pressure sores. They conclude that early hip fracture surgery appears to provide a survival benefit compared to later intervention.
Rodriguez-Fernandez et al. performed a study examining 2 groups with hip fractures. The first group was studied retrospectively and had an average delay of surgical treatment of more than 1-week while the second group was studied prospectively, and had surgical treatment within 48 hours. They found a larger number of complications in the group with a delay in surgical treatment. They conclude that elderly patients with hip fractures should be treated as soon as their medical condition permits.
Figures A and B are the AP and lateral radiographs demonstrating a right, unstable intertrochanteric femur fracture. Illustration A is an intertrochanteric femur fracture, stabilized with a cephalomedullary nail.
Incorrect Answers:
A 22-year-old healthy left hand dominant male presents to the ED with left shoulder pain after falling from an ATV. Figure A is the radiograph of his left clavicle. He is neurovascularly intact and there is no evidence of skin tenting or open fracture. Which of the following most predisposes this patient to nonunion?
Diaphyseal fracture
Fracture displacement
Age
Male Gender
Injury involving the dominant extremity
Correct answer: 2
Displaced clavicle fractures are associated with higher rates of nonunion.
Nonunion occurs in roughly 5-6% of clavicle fractures and can result in slower functional return, poor cosmesis and muscle fatigability. Clavicle fractures can be sub-classified using the Allman classification into medial, diaphyseal, and lateral injuries (Illustration A). The Neer classification for diaphyseal injuries describes fractures as "nondisplaced" (less than 100% displacement) and "displaced" (greater than 100% displacement).
Robinson et al. performed a prospective cohort study to identify risk factors for nonunion after nonoperative management of clavicle fractures. The overall nonunion rate was 6.2% and was highest in lateral third fractures (11.5%).
Diaphyseal fractures had the lowest nonunion rate (4.5%). Additionally, the authors found that the risk for nonunion was increased by advancing age, female gender, fracture displacement, and comminution.
Jorgensen et al. performed a systemic review of the literature looking for predictors of non-union and malunion in mid shaft clavicle fractures treated non-operatively. They found fracture comminution, displacement, older age, female gender, and the presence of smoking to be his factors for non-union. Of these, displacement was the most likely factor that can be used to predict nonunion.
Figure A demonstrates a displaced left clavicle diaphyseal fracture. Note that the medial fragment is displaced superiorly by the deforming force of the sternocleidomastoid. Illustration A represents the Allman classification.
Illustration B demonstrates the deforming forces acting on the clavicle.
Incorrect Answers:
A 24-year-old male presents with ankle pain after being involved in a motor vehicle accident. His injury radiograph is shown in Figure A. Which of the following has been shown to contribute to the development of post-traumatic arthritis in this injury pattern?
Initial superficial zone cartilage cell death via apoptosis at the fracture margins
Initial superficial zone cartilage cell death via apoptosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis at the fracture margins
Delayed superficial zone cartilage cell death via necrosis at the fracture margins
Figure A demonstrates a tibial plafond fracture. Initial superficial zone cartilage cell death via necrosis at the fracture margins has been shown to contribute to post-traumatic arthritis.
Post-traumatic osteoarthritis typically occurs after an intra-articular fracture. Impacted chondrocytes die by either necrosis or apoptosis, which have both been implicated in post-traumatic osteoarthritis. Initial cell death in the superficial cartilage zones at the fracture margins occurs by necrosis. Apoptosis occurs in a delayed fashion and is mitigated by several bioactive agents.
Apoptosis also affects the superficial cartilage zones near the fracture margins. Deep cartilaginous zones and areas away from the fracture margins do not seem to be involved in these processes.
McKinley et al. performed a review of the basic science of intra-articular fractures and posttraumatic osteoarthritis. They report that initial damage to the cartilage in combination with the ensuing pathomechanical and pathobiologic response of the cartilage after a fracture contribute to posttraumatic arthritis. Chronic abnormal joint loading is also thought to contribute to this process as well. They conclude that the relative contribution of each is unknown.
Tochigi et al. performed a study to determine the distribution and progression of chondrocyte damage after intra-articular ankle fractures. They harvested 7 normal human ankles and subjected them to impaction. They found that immediate superficial zone chondrocyte death was greater in fracture-edge regions than on-fracture regions. Subsequent cell death over the next 48 hours was significantly higher in fracture-edge regions as well. They conclude that cartilage damage in intra-articular fractures was characterized by chondrocyte death at fracture margins.
Figure A is an ankle mortise radiograph demonstrating an intra-articular tibial plafond fracture.
Incorrect Answers:
A 35-year-old male presents with left knee pain after sustaining the injury seen in Figure A. He is neurovascularly intact and can perform a straight leg raise, but has pain with passive range of motion. Figures B and C show an anteroposterior and lateral radiograph of the left knee, respectively. 175 cc of saline is injected into the superolateral quadrant with no egress of fluid from the inferolateral
laceration. What percentage of traumatic arthrotomies would be detected with this test?

Question 52:

In a retroperitoneal approach to the lumbar spine, what nerve is commonly found on the psoas muscle?

Options:

Ilioinguinal
Iliohypogastric
Genitofemoral
Obturator
Femoral

Correct Answer: Genitofemoral

Explanation:

Question 53:

Which of the following primary prognostic factors best predicts the outcome of the knee lesion shown in Figure 22?

Options:

Location
Size
Knee stability
Patient age
Degree of pain

Correct Answer: Patient age

Explanation:

Question 54:

Options:

Brachial plexus stretch injury
Cervical radiculopathy
Rotator cuff tendinitis
Anterior subluxation of the shoulder
Thoracic outlet syndrome

Correct Answer: Thoracic outlet syndrome

Explanation:

Question 55:

Options:

Revision total knee arthroplasty with primary quadriceps tendon repair
Hinged knee arthroplasty with full extensor mechanism allograft
Arthrotomy with debridement and antegrade knee arthrodesis nailing
Two-stage revision knee arthroplasty and quadriceps repair with Achilles allograft

Correct Answer: Arthrotomy with debridement and antegrade knee arthrodesis nailing

Explanation:

Question 56:

Options:

Silastic arthroplasty
Cheilectomy and soft-tissue interposition arthroplasty
Moberg phalangeal dorsiflexion osteotomy
Bone graft interposition arthrodesis
Waterman first metatarsal dorsal osteotomy

Correct Answer: Bone graft interposition arthrodesis

Explanation:

Question 57:

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 58:

Options:

Distal femoral/opening lateral wedge osteotomy
Distal femoral/closing lateral wedge osteotomy
High tibial osteotomy; opening medial wedge with increased tibial slope
High tibial osteotomy; closing lateral wedge with decreased tibial slope

Correct Answer: High tibial osteotomy; opening medial wedge with increased tibial slope

Explanation:

Question 59:

What is the most common non-anesthetic-related reversible cause of sustained changes in intraoperative neurophysiologic monitoring signals during spinal surgery? Review Topic

Options:

Pedicle screw misplacement
Patient positioning
Spinal cord ischemia
Retractor placement
Hypertension

Correct Answer: Patient positioning

Explanation:

Question 60:

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 61:

Which of the following statements most accurately describes the layers of articular cartilage?

Options:

The superficial zone has condensed proteoglycan and sparse collagen.
The intermediate zone transition is the thinnest layer and the chondrocytes are oriented tangentially.
The basal zone (middle, radial, deep) contains flattened chondrocytes.
Tidemark is found only in joints and not in the growing cartilage cap of an enchondroma.
Tidemark is more prominent in newborn joints.

Correct Answer: Tidemark is found only in joints and not in the growing cartilage cap of an enchondroma.

Explanation:

Question 62:

What clinical finding is associated with the least favorable prognosis in an adolescent patient who has been diagnosed with a high-grade osteosarcoma of the distal femur?

Options:

A solitary peripheral lung metastasis
Tumor crossing the physis
Extracompartmental extension
Skeletal metastasis
Tumor necrosis of 99% after chemotherapy

Correct Answer: Skeletal metastasis

Explanation:

Question 63:

Options:

classic dysplasia with volume deficient acetabula.
acetabular retroversion with positive crossover signs and ischial spine signs.
no substantial dysplasia, with normal acetabular volume and anteversion.
inadequate radiographic evidence to assess for hip dysplasia.

Correct Answer: inadequate radiographic evidence to assess for hip dysplasia.

Explanation:

Question 64:

Options:

Ultrasound
CT
Bone scan
Scapular Y-view of the shoulder
Stress views of the shoulder

Correct Answer: Stress views of the shoulder

Explanation:

Question 65:

Options:

proximal release of the proximal tendon of the rectus femoris.
release of the distal tendon of the rectus femoris.
transfer of the distal rectus femoris tendon.
V-Y lengthening of the quadriceps tendon.
Z lengthening of the patellar tendon.

Correct Answer: transfer of the distal rectus femoris tendon.

Explanation:

Question 66:

Options:

Extensor digitorum brevis
Anterior talofibular
Posterior tibial tendon
Anterior tibial tendon
Peroneus brevis tendon

Correct Answer: Peroneus brevis tendon

Explanation:

Question 67:

In the normal adult, the distance between the basion and the tip of the dens with the head in neutral position is how many millimeters?

Options:

2 to 3
4 to 5
6 to 7
7 to 8
9 to 10

Correct Answer: 4 to 5

Explanation:

Question 68:

A patient has a C6-7 herniated nucleus pulposus. What is the most likely distribution of symptoms? Review Topic

Options:

Pain in the posterior neck and scapula, numbness over the clavicle, and weakness of the head and neck extensors
Pain in the shoulder, numbness over the lateral shoulder, weakness of the deltoid
Pain at the elbow, numbness over the thumb and index finger, weakness of the biceps and wrist extensors
Pain at the forearm and hand, numbness of the middle finger, weakness of the triceps and finger extensors
Pain at the wrist, numbness in the little and ring fingers, weak finger flexors

Correct Answer: Pain at the wrist, numbness in the little and ring fingers, weak finger flexors

Explanation:

A C6-7 herniated nucleus pulposus is most likely to produce a C7 radiculopathy resulting in pain at the forearm and hand, numbness of the middle finger, and weakness of the triceps and finger extensors. Alternative answers represent sequelae of symptomatic disk herniations at C3-C4 (1), C4-C5 (2), C5-C6 (3), and C7-T1 (5), respectively.
(SBQ12SP.27) A 24-year-old male sustains the injury shown in Figure A. What was the most likely mechanism of injury?
Review Topic
Hyperextension
Flexion-distraction
Flexion-compression
Rotational
Pure axial load
Figure A shows a quadrangular fracture pattern of C5. These injuries are observed with flexion-compression loads.
Quadrangular fractures of the cervical spine are considered flexion teardrop fractures. However, they present with a larger anterior lip fragment compared to the classic teardrop fracture pattern. The radiographic findings include a quadrangular-shaped fragment from the anterior one-third of the vertebral body with significant posterior vertebral subluxation, angular kyphosis, and an increased interspinous space with facet subluxation due to disruption of the posterior elements. These are unstable fractures, and almost always require anterior and posterior stabilization.
Moore et al. studied the reliability of Cervical Spine Injury Severity Score to measure stability after cervical spine trauma. The classification system is based on morphologic descriptions and, secondly, on stability based on a quantifiable value. They showed that the Cervical Spine Injury Severity Score had excellent reliability with intra-observer intraclass correlation coefficients (ICC) >0.97 and inter-observer ICC >0.88.
Vaccaro et al. published the subaxial cervical spine injury classification system (SLIC). This systems involves 3 main categories (injury morphology, disco-ligamentous complex, and neurologic status). The overall injury severity score is obtained by summing the scores from each category. They propose that SLIC < 4 can be treated non-operatively.
Allen et al. published a classification system of cervical spine injuries which breaks injuries of the subaxial spine into six phylogenic groups based on mechanism of injury. These include: 1) flexion-compression 2) vertical-compression 3) flexion-
distraction 4) extension-compression 5) extension-distraction 6) lateral flexion. Facet
dislocation
is
caused
by
flexion-distraction
force.
Figure A shows a lateral radiograph of the cervical spine demonstrating a typical flexion-compression fracture with anteriorly displaced quadrangular fragment. Illustration A shows a flexion-compression injury. Illustration B shows the mechanism of injury for a quadrangular fracture of the cervical spine. This unstable fracture pattern is characterized by anterior column failure in flexion/compression and posterior column failure in tension. Illustration C shows an illustration of the fracture morphology according to the Allen and Ferguson classification.
Incorrect Answer 1:
Hyperextension injuries
Flexion-distraction injuries usually result in facet dislocations.

Question 69:

Options:

Osteomyelitis
Lymphoma
Myeloma
Ewing’s sarcoma
Osteosarcoma

Correct Answer: Myeloma

Explanation:

Question 70:

Figure 51 shows an arthroscopic view of the patellofemoral joint from an inferolateral portal. The arrow points to which of the following structures? Review Topic

Options:

Loose body
Plica
Displaced meniscus tear
Torn retinaculum
Osteochondral defect

Correct Answer: Plica

Explanation:

Question 71:

What is the primary problem in rickets osteomalacia?

Options:

Defect in the zone of proliferation within the physis
Defect in type I collagen
Defect in the ext-1 gene
Low level of calcium
Production of dysplastic fibrous bone

Correct Answer: Low level of calcium

Explanation:

Question 72:

Options:

Complete metabolic workup
Advanced imaging with a CT scan
Laboratory studies for CBC, ESR and CRP
Nuclear medicine studies

Correct Answer: Laboratory studies for CBC, ESR and CRP

Explanation:

Question 73:

In revision total hip arthroplasty, an acetabular reconstruction cage is best indicated for which of the following patterns of bone loss?

Options:

Enlarged acetabular rim
Cavitary central defect
Superior migration of 2 cm
Deficient anterior wall
Pelvic discontinuity

Correct Answer: Pelvic discontinuity

Explanation:

Question 74:

Options:

Immediate full weight bearing
Protected weight bearing
Toe touch weight bearing
Non-weight-bearing
50% weight bearing

Correct Answer: Immediate full weight bearing

Explanation:

DISCUSSION: The incidence of femoral fracture in primary cementless total hip arthroplasty ranges from 1.5% to 27.8%. It is imperative that the implant and fracture are stable both intraoperatively and postoperatively. Cerclage wiring or cerclage cabling is the current recommended treatment for nondisplaced calcar fractures and minimally displaced proximal fractures. Berend and associates reviewed the results of 58 total hips in 55 patients with intraoperative calcar fracture managed with single or multiple cerclage wires or cables and immediate full weight bearing. Follow-up averaged 7.5 years, and there were no revisions of the femoral component. No patients had severe thigh pain.
REFERENCES: Berend KR, Lombardi AV Jr, Mallory TH, et al: Cerclage wires or cables for the management of intraoperative fracture associated with a cementless, tapered femoral prosthesis: Results at 2 to 16 years. J Arthroplasty 2004;19:17-21.
Schmidt AH, Kyle RF: Periprosthetic fractures of the femur. Orthop Clin North Am 2002;33:143-152.
Greidanus NV, Mitchell PA, Masri BA, et al: Principles of management and results of treating the fractured femur during and after total hip arthroplasty. Instr Course Lect 2003;52:309-322.

Question 75:

A 4-year-old girl sustains an isolated spiral femoral fracture after falling from her tricycle. Management should consist of

Options:

external fixation.
plate fixation.
skeletal traction for 5 weeks.
immediate spica cast immobilization.
flexible nailing with titanium nails.

Correct Answer: immediate spica cast immobilization.

Explanation:

Question 76:

..Figure 93 is the radiograph of a 72-year-old woman. Treatment includes fixation of the ulna. What options are recommended for the radius?

Options:

Radial head replacement to restore radiocapitellar contact
Radial head excision because there is no risk for posterolateral instability
Percutaneous fixation to avoid the risk for stiffness after surgery
Allograft reconstruction to prevent capitellar erosion DISCUSSION.. Prosthetic replacement is an appropriate option in cases of a nonreconstructable fracture to restore the radiocapitellar contact. Most complex fractures are associated with instability; therefore, it is advisable to consider open reduction and internal fixation or radial head replacement when the injury involves a dislocation or fracture of the ulna. Simple radial head excision may be a viable option for a comminuted fracture without instability or associated ulnar fracture. When the radial head is replaced, caution must be exercised to avoid overstuffing the joint because this can lead to stiffness from impingement, capitellar erosion, loss of flexion, or synovitis.

Correct Answer: Radial head replacement to restore radiocapitellar contact

Explanation:

CLINICAL SITUATION FOR QUESTIONS 94 THROUGH 96
Figure 94 is the anteroposterior radiograph of a 75-year-old woman who has a 5-year history of progressive pain, crepitus, and loss of motion in her shoulder. She had a rotator cuff repair 10 years ago. Examination reveals 60 degrees of active forward elevation and 20 degrees of external rotation with her arm at her side. Passively she can be brought to 160 degrees of forward elevation and 90 degrees of external rotation with her arm at her side. A glenohumeral joint injection with local anesthetic eliminated pain, but there is no observed change in active motion.

Question 77:

Options:

Stabilize the present reduction internally with intramedullary pins.
Accept the present reduction and obtain follow-up radiographs in 1 week.
Remanipulate the fracture and place the forearm in pronation.
Remanipulate the fracture and place the forearm in supination.
Stabilize the present reduction with plates and screws.

Correct Answer: Remanipulate the fracture and place the forearm in supination.

Explanation:

Question 78:

Options:

Aspiration of joint fluid to obtain a cell count
Revision of the UKA using primary total knee arthroplasty (TKA) components
Revision of the UKA using a revision TKA with augments
Procurement of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level

Correct Answer: Procurement of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level

Explanation:

Question 79:

The difference between vitamin D-dependent rickets type I (VDDR I) and vitamin D-dependent rickets type II (VDDR II) is

Options:

VDDR I is caused by an inactivating mutation of the receptor for 1,25 (OH)2 vitamin D3. VDDR II is a deficiency of an enzyme predominantly found in the kidney.
VDDR I is caused by an activating mutation of the receptor for 1,25 (OH)2 vitamin D3. VDDR II is a deficiency of an enzyme predominantly found in the kidney.
VDDR I is a deficiency of an enzyme predominantly found in the kidney. VDDR II is caused by an inactivating mutation of the receptor for 1,25 (OH)2 vitamin D3.
VDDR I is a deficiency of an enzyme predominantly found in the kidney. VDDR II is caused by an activating mutation of the receptor for 1,25 (OH)2 vitamin D3.
VDDR I is a deficiency of an enzyme predominantly found in the liver. VDDR II is caused by an inactivating mutation of the receptor for 1,25 (OH)2 vitamin D3.

Correct Answer: VDDR I is caused by an inactivating mutation of the receptor for 1,25 (OH)2 vitamin D3. VDDR II is a deficiency of an enzyme predominantly found in the kidney.

Explanation:

Question 80:

Augmentation of a Broström repair with the mobilized lateral portion of the extensor retinaculum (Gould modification) is expected to produce

Options:

higher risk for iatrogenic nerve injury.
decreased ankle range of motion 6 weeks after surgery.
no significant biomechanical difference in initial ankle stability.
a significantly lower incidence of osteoarthritis on long-term follow-up.

Correct Answer: no significant biomechanical difference in initial ankle stability.

Explanation:

Question 81:

In which scenario is application of NPWT contraindicated?

Options:

- Fasciotomy wound after compartment syndrome
- Exposed bone after debridement
- Surgical wound that cannot be closed because of tension
- Surgical tumor bed after excision while awaiting final pathology and definitive closure

Correct Answer: - Surgical tumor bed after excision while awaiting final pathology and definitive closure

Explanation:

DISCUSSION
The most common complication associated with NPWT is a rash on the skin resulting from contact with a suction sponge. In a 2001 study by Webb and Schmidt, 2.2% of patients treated with NPWT had a rash that resolved within 48 hours. To minimize risk for this rash, care should be taken to avoid overlap of the sponge onto intact skin. If skin overlap is unavoidable, a lower-pressure setting should be used.
Acute bacterial infection is possible in this scenario, but there would likely be additional findings such as purulence in the wound itself. Similarly, an acute allergic reaction could be found within the wound and not just at the skin edge. Skin irritation from excessive adhesive plastic tension can result in blistering or shearing avulsion but not skin-edge erythema. Skin necrosis from the original trauma would result in skin-edge duskiness instead of erythema.
A study by Timmers and associates showed a statistically significant increase in microvascular blood flow to the skin under a sponge at subatmospheric pressures. Angiogenesis occurs in the area of the wound vacuum from the negative pressure and increased blood flow, not from the sponge material itself. There has been no indication that antibiotic concentration is increased in the setting of negative pressure therapy because antibiotics would be evacuated along with the fluid. NPWT does not result in increased temperatures that would kill pathogens.
NPWT is contraindicated in the setting of neoplasm because its effect on tumors is unknown. There is potential for increased angiogenesis in residual tumor cells, which could lead to recurrence or even metastasis. NPWT has been used safely and effectively for coverage of open fractures between initial debridement and definitive coverage. Fasciotomy wounds are frequently covered with NPWT dressings on a temporary basis with excellent results.
NPWT has been used to temporize wounds with exposed bone before flap coverage. Wounds with excessive tension frequently can be closed after short-term coverage with NPWT dressings.
RECOMMENDED READINGS
Webb LX, Schmidt U. [Wound management with vacuum therapy]. Unfallchirurg. 2001 Oct;104(10):918-26. German. PubMed PMID: 11699301.
View Abstract at PubMed
Webb LX. New techniques in wound management: vacuum-assisted wound closure. J Am Acad Orthop Surg. 2002 Sep-Oct;10(5):303-11. PubMed PMID: 12374481.
View Abstract at
PubMed
Timmers MS, Le Cessie S, Banwell P, Jukema GN. The effects of varying degrees of pressure delivered bynegative-pressure wound therapy on skin perfusion. Ann Plast Surg. 2005 Dec;55(6):665-71. PubMed PMID: 16327472.
View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 68 AND 69
Figure 68 is the radiograph of a 17-year-old girl who is treated with closed reduction and percutaneous screw fixation for her displaced femoral neck fracture. Capsulotomy of the hip is not performed. After surgery, the patient is instructed to maintain touch-down weight-bearing status for 3 months.

Question 82:

A 25-year-old student sustains the injury shown in Figures 13a through 13c after falling off a curb. Initial management should consist of

Options:

weight bearing as tolerated in a hard-soled shoe.
weight bearing as tolerated in an ankle lacer.
weight bearing as tolerated in a short leg cast.
non-weight-bearing in a hard-soled shoe.
non-weight-bearing in a short leg cast.

Correct Answer: non-weight-bearing in a short leg cast.

Explanation:

Question 83:

Options:

Correct Answer: 50%

Explanation:

Question 84:

Creatine is currently being used by athletes as a dietary supplement in an attempt to enhance performance. What is the physiologic basis for its use?

Options:

Assists in carbohydrate metabolism and glycogen synthesis by producing adenosine diphosphate (ADP) to enhance aerobic activities
Converts to phosphocreatine (PCr), which acts as an energy reservoir for adenosine triphosphate (ATP) in muscle tissue
Converts to PCr, which enhances the production of ADP and promotes the metabolism of triglycerides as an energy source
Converts to PCr, which enhances the production of ADP and promotes the metabolism of proteins as an energy source
Converts to ADP by creatine kinase (CK) providing an energy reservoir for the production of ATP

Correct Answer: Converts to phosphocreatine (PCr), which acts as an energy reservoir for adenosine triphosphate (ATP) in muscle tissue

Explanation:

Question 85:

Options:

Suture anchor repair of the labral tear and no bony resection
Suture anchor repair of the labral tear and bony resection of the pincer lesion
Debridement of the labral tear and bony resection of the pincer lesion
Debridement of the labral tear with no bony resection of the pincer lesion

Correct Answer: Suture anchor repair of the labral tear and bony resection of the pincer lesion

Explanation:

DISCUSSION FOR QUESTIONS 26 THROUGH 29
The clinical scenario, examination, and MRI scans are consistent with a pincer-type FAI. The decreased range of motion is secondary to the pain produced by the continued abutment of the femoral head against the anterosuperior acetabulum. Flexing the hip while internally rotating and adducting the leg recreates this contact and is typically painful. No clinical signs suggest sacroiliac joint arthritis, an intra-articular loose body, or trochanteric bursitis, although these are all diagnoses that should be considered in a patient with a painful hip. The most sensitive and specific study to detect an acetabular labral tear is an MRI arthrogram of the hip. This study should be obtained in this patient to evaluate the labrum as well as the status of the articular cartilage. An MRI scan without intra-articular contrast is not as sensitive as an arthrogram. An ultrasound can provide a dynamic assessment of the hip and help in the setting of a snapping hip; however, this study is not reliable to determine the presence of a labral tear. In the setting of pincer FAI, the forced leverage of the anterosuperior femoral head upon the anterior acetabulum results in abnormal forces against the posteroinferior acetabulum. This continued force can lead to a chondral lesion in this location know as a “counter-coup” injury. Chondral lesions of the femoral head are rare in the setting of pincer FAI. The posterosuperior quadrant does not experience increased force and rarely sustains chondral injuries. The patient is a young, active individual with no pre-existing degenerative changes, so repair of the tear with bony resection of the pincer lesion is the most appropriate treatment.A capsulolabral detachment should be repaired because these tears can heal and the labrum functions as a seal, preventing egress of synovial fluid from the joint space. If the pincer lesion is not resected, the patient will continue to experience abnormal contact and the repair will likely fail. There is no evidence that the patient has a cam impingement, and recontouring of the femoral head/neck junction is not appropriate. Simple debridement should be reserved for intrasubstance tears of the labrum, which would not be expected to heal with repair.
CLINICAL SITUATION FOR QUESTIONS 30 THROUGH 32
Figures 30a and 30b are the radiographs of a 20-year-old college multisport athlete who has had longstanding pain in his left hip. He denies any specific event that initiated his pain, but he notes that he had hip problems when he was an infant. He denies pain with activities of daily living, but he
believes his pain is increasingly limiting his ability to exercise. He localizes the pain to his groin. He denies low-back or buttock pain or pain that radiates down his leg.

Question 86:

Which of the following preoperative findings is a predictor of poor outcome following arthroscopic debridement for glenohumeral arthritis? Review Topic

Options:

Shoulder stiffness
History of infection
Nonconcentric joint space on preoperative radiographs
Intra-articular loose bodies
History of instability

Correct Answer: Nonconcentric joint space on preoperative radiographs

Explanation:

Question 87:

Options:

closed reduction and cast immobilization.
open reduction and internal fixation (ORIF).
arthrodesis.
resection arthroplasty.

Correct Answer: open reduction and internal fixation (ORIF).

Explanation:

Question 88:

Options:

proximal biceps tenodesis.
application of a sling for 3 weeks, followed by physical therapy.
anterior capsulolabral reconstruction.
repair of the subscapularis tendon.
repair of the pectoralis major tendon.

Correct Answer: repair of the pectoralis major tendon.

Explanation:

Question 89:

Options:

she can expect to have good pain relief following surgery.
active forward elevation and external rotation are reliably obtained postoperatively.
with her current anterosuperior escape, she is likely to have a poor surgical result.
postoperatively, significant muscular atrophy in the latissimus dorsi commonly occurs.
no advancement in glenohumeral arthritic changes should occur following surgery.

Correct Answer: with her current anterosuperior escape, she is likely to have a poor surgical result.

Explanation:

DISCUSSION: Latissimus dorsi tendon transfer is considered a surgical option for treatment in patients with chronic supraspinatus and infraspinatus tendon tears. Preoperative subscapularis function is necessary for good clinical results. Additionally, men with active elevation to shoulder level and active external rotation to 20 degrees have predictably good results. Women with active shoulder elevation limited to below chest level have poor results from this procedure and should not be considered candidates. Postoperatively they lack pain control, active elevation, and active external rotation. Muscular atrophy in the latissimus dorsi does not occur, and glenohumeral arthritic changes frequently develop postoperatively.
REFERENCES: Gerber C, Maquieira G, Espinosa N: Latissimus dorsi transfer for the treatment of irreparable rotator cuff tears: Factors affecting outcome. J Bone Joint Surg Am
2006;88:113-120.
Iannotti JP, Hennigan S, Herzog R, et al: Latissimus dorsi tendon transfer for irreparable posterosuperior rotator cuff tears. J Bone Joint Surg Am 2006;88:342-348.

Question 90:

Options:

Surgical approach
Location of the transverse fracture
Timing of surgery
Accuracy of reduction
Use of skeletal traction

Correct Answer: Accuracy of reduction

Explanation:

DISCUSSION: The patient has a very low T-type acetabular fracture; however, the head is not congruent under the dome so surgical reduction is necessary. The anterior and posterior columns are displaced and will move independent from each other. The extended iliofemoral is the only approach allowing for visualization and reduction of each column. A combined anterior and posterior approach may also be used. The timing of surgery should be within the first 3 weeks of injury to optimize chances of obtaining an accurate reduction because this is an important factor in determining outcome.
REFERENCES: Letournel E, Judet R (eds): Fractures of the Acetabulum, ed 2.
Berlin, Germany, Springer-Verlag, 1991.
Matta JM: Fractures of the acetabulum: Accuracy of reduction and clinical results in patients managed operatively within three weeks after the injury. J Bone Joint Surg Am
1996;78:1632-1645.

Question 91:

Options:

observation with repeat radiographs in 6 months.
a thoracolumbosacral orthosis (TLSO).
in situ posterior spinal fusion without instrumentation, followed by full-time TLSO bracing.
anterior spinal convex hemiepiphysiodesis.
combined anterior and posterior spinal arthrodesis with instrumentation.

Correct Answer: combined anterior and posterior spinal arthrodesis with instrumentation.

Explanation:

Question 92:

Options:

bed rest only for 6 weeks.
mobilization in a kinetic therapy bed for 6 weeks, followed by a hyperextension brace.
a total contact thoracolumbosacral orthosis and rapid mobilization.
anterior decompression, vertebral reconstruction, and stabilization.
posterior reduction, stabilization, and grafting.

Correct Answer: a total contact thoracolumbosacral orthosis and rapid mobilization.

Explanation:

Question 93:

The patient undergoes further testing and it is discovered that the lesion encompasses 70% of the joint. What is the best next treatment option?

Options:

Arthroscopic debridement
Subtalar arthroereisis
Subtalar fusion
Lesion resection

Correct Answer: Subtalar fusion

Explanation:

DISCUSSION
A tarsal coalition is an abnormal connection of 2 or more bones in the foot. Although tarsal coalitions are present at birth, children and adults typically do not show signs of the disorder until early adolescence or later. The exact incidence of the disorder is hard to determine; however, it is caused by a gene mutation that affects cells that produce the tarsal bones. The 2 most common locations for tarsal coalitions are between the calcaneus and the navicular or between the talus and the calcaneus. It is estimated that 1 out of every 100 people may have a tarsal coalition. In 50% of cases, both feet are affected. Tarsal coalitions are rarely discovered until symptoms arise. Symptoms may include stiff and painful feet, a rigid flatfoot, or increased pain or a limp with high-level activities. Upon examination, symptoms may include tenderness in the area of the coalition, loss of motion, rigid flat feet, and arthritic changes of the joint. Imaging studies begin with radiographs. A CT scan can provide bony detail for imaging tarsal coalitions and determining the extent of the coalition and any accompanying degenerative change. MRI can provide details of the soft tissues. Treatment includes nonsurgical care including rest, orthotics, a temporary boot or cast, and injections. Surgical options include resection with interposition of muscle or fatty tissue from another area of the body or fusions when large (exceeding 50% of the joint), more severe coalitions are encountered.
RECOMMENDED READINGS
Lemley F, Berlet G, Hill K, Philbin T, Isaac B, Lee T. Current concepts review: Tarsal coalition. Foot Ankle Int. 2006 Dec;27(12):1163-9. Review. PubMed PMID: 17207452.
View Abstract
at PubMed
Badgley CE. Coalition of the calcaneus and the navicular. Arch Surg. 1927;15:75-88. Conway JJ, Cowell HR. Tarsal coalition: clinical significance and roentgenographic demonstration. Radiology. 1969 Mar;92(4):799-811. PubMed PMID: 5767760.
View Abstract
at PubMed
Herzenberg JE, Goldner JL, Martinez S, Silverman PM. Computerized tomography of talocalcaneal tarsal coalition: a clinical and anatomic study. Foot Ankle. 1986 Jun;6(6):273-

Question 94:

Options:

a scapular and rotator cuff strengthening program.
arthroscopy.
review of her golf technique.
humeral head replacement.
an erythrocyte sedimentation rate.

Correct Answer: a scapular and rotator cuff strengthening program.

Explanation:

Question 95:

Fluoroquinolones work by inhibiting what enzyme?

Options:

DNA gyrase
RNA gyrase
DNA polymerase
Ribosomal transferase
DNA telomerase

Correct Answer: DNA gyrase

Explanation:

Question 96:

Options:

methylprednisolone and observation.
posterior laminectomy and spinal fusion.
anterior spinal fusion.
halo vest immobilization.
posterior laminectomy followed by halo vest immobilization.

Correct Answer: posterior laminectomy and spinal fusion.

Explanation:

Question 97:

Options:

fracture kyphosis.
reduction of retropulsed bone.
pain reduction.
incidence of complications.
return to work.

Correct Answer: incidence of complications.

Explanation:

Question 98:

Options:

significantly reduced wear and greater mid-term implant survival.
increased wear and increased fracture rate of the liner.
decreased mid-term implant survival when compared with UHMWPE.
reduced wear, but increased osteolysis. XLPE was developed to address the problem of wear and osteolysis associated with conventional UHMWPE-bearing surfaces. Data have shown, with randomized controlled trials, that XLPE liners have significantly reduced wear and are associated with greater implant survival at 10 years compared with UHMWPE-bearing surfaces.

Correct Answer: increased wear and increased fracture rate of the liner.

Explanation:

Question 99:

Options:

radial head resection.
dynamic splinting.
metacarpophalangeal arthroplasties.
total wrist arthrodesis with a flexor digitorum sublimis to extensor digitorum communis transfer.
distal ulnar resection with an extensor indius proprius to extensor digitorum communis transfer.

Correct Answer: distal ulnar resection with an extensor indius proprius to extensor digitorum communis transfer.

Explanation:

DISCUSSION: The patient has extensor tendon ruptures at the level of the wrist that are the result of synovitis at the distal radioulnar joint (Vaughn-Jackson syndrome). Extensor indius proprius transfer appropriately matches strength and excursion of the ruptured extensor digiti quinti and extensor digitorum communis tendons. An extensor tenosynovectomy with distal radioulnar joint resection decreases the synovitis, which if left untreated may cause additional tendon ruptures. Radial head resection is used for posterior interosseous nerve compression secondary to radial head synovitis, and in this patient only two fingers are involved, which rules out this diagnosis. Dynamic splinting is not indicated for ruptured tendons. Metacarpophalangeal arthroplasties and imbrication of the sagittal bands are used for metacarpophalangeal arthritis and extensor tendon subluxation. If this was the problem, the patient should be able to maintain the fingers in extension after they are passively extended. Total wrist arthrodesis prevents the tenodesis effect, thus limiting effective tendon excursion and making the proposed transfer less effective.
REFERENCES: Feldon P, Terrono AL, Nalebuff EA, et al: Rheumatoid arthritis and other connective tissue diseases: Tendon ruptures, in Green DP, Hotchkiss RN, Pederson WC (eds): Green’s Operative Hand Surgery, ed 4. New York, NY, Churchill Livingstone, 1999,
pp 1669-1684.
Moore JR, Weiland AJ, Valdata L: Tendon ruptures in the rheumatoid hand: Analysis of treatment and functional results in 60 patients. J Hand Surg Am 1987;12:9-14.
Leslie BM: Rheumatoid extensor tendon ruptures. Hand Clin 1989;5:191-202.

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

Orthopedic Board Review MCQs: Spine, Knee & Tendon | Part 176

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 176

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index