Arthroplasty, Knee, Shoulder, Trauma Ortho MCQs - Part 225

About This Board Review Set

This is Part 225 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

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

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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 225

This module focuses heavily on: Arthroplasty, Knee, Nerve, Shoulder, Trauma.

Sample Questions from This Set

Sample Question 1: Which of the following factors is associated with failure of arthroscopic excision of the distal clavicle?...

Sample Question 2: An otherwise healthy 45-year-old woman reports the onset of severe right leg pain. Figure 20a shows an axial MRI scan of the L4-5 level, and Figure 20b shows a sagittal view with the arrow at the L4-5 level. What nerve root is the most like...

Sample Question 3: A surgeon performs a minimally invasive total knee arthroplasty through a quadriceps-sparing approach using medial-to-lateral cutting jigs. When beginning therapy that afternoon, the patient can passively but not actively extend her knee, a...

Sample Question 4: If a surgeon inadvertently burrs through the midlateral wall of C5 during a anterior corpectomy, what structure is at greatest risk for injury?...

Sample Question 5: A 70-year-old man seen in the emergency department has had left shoulder pain and a fever of 101.5 degrees F (38.6 degrees C) for the past 3 days. He denies any history of trauma. Examination reveals tenderness anterosuperiorly and at the p...

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

Which of the following factors is associated with failure of arthroscopic excision of the distal clavicle?

Explanation

DISCUSSION: Uneven resection of bone, typically leaving a retained posterolateral corner of the distal clavicle, can lead to failure of arthroscopic distal clavicle excision. The amount of bone resected, the gender of the patient, or the diagnosis (osteoarthritis versus osteolysis) does not appear to affect the results.
REFERENCE: Flatow EL, Duralde XA, Nicholson GP, Pollock RG, Bigliani LU: Arthroscopic resection of the distal clavicle with a superior approach. J Shoulder Elbow Surg 1995;4:41-50.

Question 2

An otherwise healthy 45-year-old woman reports the onset of severe right leg pain. Figure 20a shows an axial MRI scan of the L4-5 level, and Figure 20b shows a sagittal view with the arrow at the L4-5 level. What nerve root is the most likely source of her pain?

Explanation

DISCUSSION: The scans show a disk herniation in the far lateral region of the disk. In particular, the sagittal view shows the herniation adjacent to the exiting L4 nerve root. Disk herniations in this area that cause symptoms are more likely to compress the nerve exiting at the same level rather than the next most caudal level.
REFERENCES: McCulloch JA: Microdiscectomy, in Frymoyer JW (ed): The Adult Spine: Principles and Practice. New York, NY, Raven Press, 1991, vol 2, pp 1765-1783.
Hodges SD, Humphreys SC, Eck JC, Covington LA: The surgical treatment of far lateral L3-L4 and L4-L5 disc herniations: A modified technique and outcomes analysis of 25 patients. Spine 1999;24:1243-1246.

Question 3

A surgeon performs a minimally invasive total knee arthroplasty through a quadriceps-sparing approach using medial-to-lateral cutting jigs. When beginning therapy that afternoon, the patient can passively but not actively extend her knee, although she has minimal knee pain. All regional blocks have been discontinued. What is the most likely reason for this finding?

Explanation

DISCUSSION
This patient lacks active knee extension. It is not attributable to the regional block because that block is no longer acting. The most likely cause is laceration of the patella tendon, which has been described during both large-incision surgery and minimally invasive surgery. However, this is reported with increased frequency during minimally invasive surgery. Quadriceps inhibition, avulsion of the quadriceps tendon, and femoral nerve palsy can cause lack of active extension, but these problems are less likely because the patient has minimal pain.

Question 4

If a surgeon inadvertently burrs through the midlateral wall of C5 during a anterior corpectomy, what structure is at greatest risk for injury?

Explanation

DISCUSSION: The vertebral artery is contained within the vertebral foramen and thus tethered alongside the vertebral body, making it vulnerable to injury if a drill penetrates the lateral wall. The C5 root passes over the C5 pedicle and is not in the vicinity. The C6 root passes under the C5 pedicle but is posterior to the vertebral artery and is only vulnerable at the very posterior-inferior corner. The carotid artery and the vagus nerve are both within the carotid sheath and well anterior.
REFERENCES: Pfeifer BA, Freidberg SR, Jewell ER: Repair of injured vertebral artery in anterior cervical procedures. Spine 1994;19:1471-1474.
Gerszten PC, Welch WC, King JT: Quality of life assessment in patients undergoing nucleoplasty-based percutaneous discectomy. J Neurosurg Spine 2006;4:36-42.

Question 5

A 70-year-old man seen in the emergency department has had left shoulder pain and a fever of 101.5 degrees F (38.6 degrees C) for the past 3 days. He denies any history of trauma. Examination reveals tenderness anterosuperiorly and at the posterior glenohumeral joint line. He has very limited range of motion (passive and active). Laboratory studies show a WBC count of 12,000/mm 3 and an erythrocyte sedimentation rate of 48 mm/h. Initial management should consist of

Explanation

DISCUSSION: It appears that the patient has septic arthritis of the glenohumeral joint; therefore, initial management should consist of aspiration of the glenohumeral joint and subacromial space separately, followed by Gram stain and culture of the fluid. Based on the findings, broad-spectrum IV antibiotics should be started. If the diagnosis of septic arthritis is confirmed, then arthroscopic or open surgical drainage usually is indicated.
REFERENCES: Sawyer JR, Esterhai JL Jr: Shoulder infections, in Warner JJ, Iannotti JP, Gerber C (eds): Complex and Revision Problems in Shoulder Surgery. Philadelphia, PA, Lippincott-Raven, 1997.
Leslie BM, Harris JM, Driscoll D: Septic arthritis of the shoulder in adults. J Bone Joint Surg Am 1989;71:1516-1522.

Question 6

A 56-year-old man who tripped and fell out of his golf cart onto his right shoulder 4 days ago now reports mild pain while chipping. Examination reveals mild bruising over the lateral clavicle but good shoulder range of motion and strength. A radiograph is shown in Figure 9. Appropriate treatment at this time should include which of the following?

Explanation

Treatment of this minimally displaced distal clavicle fracture should begin with nonsurgical management consisting of sling therapy followed by gentle motion therapy. Any form of surgical intervention at this time is unnecessary because this fracture pattern has a high incidence of union. A bone stimulator may be used if healing becomes delayed.

Question 7

What ligament is the primary stabilizer of the wrist following a proximal row carpectomy?

Explanation

DISCUSSION: The radioscaphocapitate ligament is the prime stabilizer between the radius and capitate, preventing ulnar translocation of the carpus. Its oblique orientation prevents the carpus from drifting ulnarly. This stout ligament must be protected when excising the scaphoid.
REFERENCES: Stern PJ, Agabegi SS, Kiefhaber TR, et al: Proximal row carpectomy. J Bone Joint Surg Am 2005;87:166-174.
Wyrick JD: Proximal row carpectomy and intercarpal arthrodesis for the management of wrist arthritis. J Am Acad Orthop Surg 2003;11:227-281.

Question 8

A 65-year-old man has had “catching” in front of his knee since he had a total knee arthroplasty 9 months ago. Examination reveals a palpable and audible snap in the anterior aspect of the knee at about 40 degrees of flexion as the knee is being actively extended. A radiograph of the prosthetic knee will most likely show

Explanation

The patellar “clunk” syndrome is an infrequent complication of TKA. It is diagnosed clinically by a clunking or clicking sensation or sound as the flexed knee is extended usually at about 30-40 degrees of flexion.
Pathologically, the clunk is produced by a suprapatellar fibrous nodule seen superior to the patellar component at re-operation. This nodule has been seen to catch in the intercondylar notch in primarily first generation TKAs. Current component designs have decreased this phenomenon through better engineering of femoral components. Treatment is by arthroscopic debridement or open arthroplasty resection. The nodule may be recurrent.

Question 9

A 2-year-old child is being evaluated for limb-length and girth discrepancy. As a newborn, the patient was large for gestational age and had hypoglycemia. Current examination shows enlargement of the entire right side of the body, including the right lower extremity and foot. The skin shows no abnormal markings, and the neurologic examination is normal. The spine appears normal. Radiographs confirm a 2-cm discrepancy in the lengths of the lower extremities. Additional imaging studies should include

Explanation

DISCUSSION: The patient may have Beckwith-Wiedemann syndrome (BWS), which consists of exophthalmos, macroglossia, gigantism, visceromegaly, abdominal wall defects, and neonatal hypoglycemia. Hemihypertrophy develops in approximately 15% of patients with BWS. Patients with hemihypertrophy that is the result of BWS have a 40% chance of developing malignancies such as Wilms’ tumor or hepatoblastoma; therefore, frequent ultrasound screening is recommended until about age 7 years. The absence of nevi and vascular markings helps to rule out other causes of hemihypertrophy, such as neurofibromatosis, Proteus syndrome, and Klippel-Trenaunay syndrome. Bone age estimations are not accurate at this young age but may become more useful later to help predict the timing of epiphysiodesis procedures.
REFERENCES: DeBaun MR, Tucker MA: Risk of cancer during the first four years of life in children from The Beckwith-Wiedemann Syndrome Registry. J Pediatr 1998;132:398-400.
Ballock RT, Wiesner GL, Myers MT, et al: Hemihypertrophy concepts and controversies.

J Bone Joint Surg Am 1997;79:1731-1738.
Carpenter CT, Lester EL: Skeletal age determination in young children: Analysis of three regions of the hand/wrist film. J Pediatr Orthop 1993;13:76-79.

Question 10

When balancing gaps in the coronal plane, what structure preferentially impacts the flexion space more than the extension space?

Explanation

DISCUSSION:
In the setting of valgus deformities, TKA poses different challenges than those encountered when varus deformities are present. Most valgus alignment is attributable to a deformity of the distal femur rather than of the proximal tibia, as seen in varus knees. One of the major anatomical differences is a hypoplastic lateral femoral condyle which, when not recognized and used as a rotational reference point,
can lead to internal rotation of the femoral component. This malrotation in turn leads to patellofemoral maltracking or instability, which is a common complication associated with primary TKA.

Question 11

A 35-year-old carpenter sustained an injury to his dominant shoulder in a fall. He reports that he felt a sharp tearing sensation as he held on to a scaffold to keep from falling. Examination reveals swelling and ecchymosis down the upper arm, weakness to internal rotation, and deformity of the anterior axilla. He has good strength in external rotation and no apprehension with instability testing. Radiographs are normal. Management should consist of

Explanation

DISCUSSION: The findings are classic for a pectoralis major tendon avulsion. Deformity of the anterior axillary fold is a classic finding, and ecchymosis down the arm suggests that the injury is at the humeral attachment rather than at the musculotendinous junction. Good external rotation strength indicates that function in the supraspinatus and infraspinatus has been preserved. The treatment of choice for a tendon avulsion in a young individual is early surgical repair. Conversely, if the injury is within the muscle or at the musculotendinous junction, initial nonsurgical management is recommended. If the location of the injury cannot be determined by physical examination, then MRI of the pectoralis major can be helpful.
REFERENCES: Hanna CM, Glenny AB, Stanley SN, et al: Pectoralis major tears: Comparison of surgical and conservative treatment. Br J Sports Med 2001;35:202-206.
Connell DA, Potter HG, Sherman MF, et al: Injuries of the pectoralis major muscle: Evaluation with MR imaging. Radiology 1999;210:785-791.

Question 12

Figures A through C are the radiograph and CT scans of a 42-year-old man who sustained an injury to both of his ankles and underwent surgical repair 2 weeks prior to presentation to your office. One ankle is healing well. On the contralateral side, he reports pain and restricted ankle range of motion. Management should consist of

Explanation

This patient has a malreduced syndesmosis. The CT scans clearly show the fibula to be subluxated posteriorly relative to the incisura; therefore, surgical revision is warranted. Revision surgery should include either removal of the current screws with accurate reduction of the syndesmosis and new screw placement or repair of the posterior malleolar fragment, which will in turn reduce the syndesmosis. Addition of an anteriorly directed screw to the current construct will not change the malalignment. Loosening the syndesmotic screws or addition of aggressive physiotherapy will not correct the malrotation of the distal fibula within the incisura which is seen on the CT scan. Outcomes after these injuries are related to the reduction of the ankle mortise.

Question 13

A 28-year-old woman has a moderate hallux valgus deformity and a prominence of the medial eminence. She can participate in all activities and reports that she could wear 3-inch heels in the past, but she now notes medial eminence pain even while wearing a soft leather flat shoe with a cushioned sole. She requests recommendations regarding surgical correction. Examination reveals a 1-2 intermetatarsal angle of 10 degrees. A clinical photograph and radiograph are shown in Figures 13a and 13b. What is the best course of action?

Explanation

DISCUSSION: Based on her symptoms and prior shoe wear modifications, the treatment of choice is surgical correction of the hallux valgus with a chevron osteotomy. There are no data to support the use of a custom orthosis to delay the progression of a hallux valgus deformity. Steroid injection would only risk infection, as well as joint and capsule damage. Extra-depth shoes are an option; however, the patient is interested in surgical options.
REFERENCES: Chou LB, Mann RA, Casillas MM: Biplanar chevron osteotomy. Foot Ankle Int 1998;19:579-584.
Coughlin MJ: Roger A. Mann Award: Juvenile hallux valgus. Etiology and treatment. Foot Ankle Int 1995;16:682-697.
Pochatko DJ, Schlehr FJ, Murphey MD, Hamilton JJ: Distal chevron osteotomy with lateral release for treatment of hallux valgus deformity. Foot Ankle Int 1994;15:457-461.

Question 14

A patient has a humeral shaft fracture and is scheduled to undergo open reduction and internal fixation with a plate. What surgical approach will provide the greatest amount of exposure?

Explanation

DISCUSSION: The modified posterior approach with elevation of the medial and lateral heads of the triceps can provide exposure of 94% of the humeral shaft. The traditional posterior triceps-splitting approach exposes 55% of the humeral shaft.
REFERENCES: DeFranco MJ, Lawton JN: Radial nerve injuries associated with humeral fractures. J Hand Surg Am 2006;31:655-663.
Gerwin M, Hotchkiss RN, Weiland AJ: Alternative operative exposure of the posterior aspect of the humeral diaphysis with reference to the radial nerve. J Bone Joint Surg Am 1996;78:1690-1695.

Question 15

The lower extremity motor dysfunction in Charcot-Marie-Tooth disease most commonly involves which of the following muscles?

Explanation

DISCUSSION: The motor dysfunction in Charcot-Marie-Tooth disease involves the tibialis anterior muscle. Charcot-Marie-Tooth disorders most commonly cause distal motor dysfunction in the foot intrinsics, anterior compartment musculature, and peroneals. There is evidence that the peroneus brevis is affected selectively and the peroneus longus is spared. This is based on clinical muscle testing, muscle cross-sections on MRI, and electrodiagnostic testing.
REFERENCES: Mann RA, Missirian J: Pathophysiology of Charcot-Marie-Tooth disease. Clin Orthop 1988;234:221-228.
Tynan MC, Klenerman L, Helliwell TR, Edwards RH, Hayward M: Investigation of muscle imbalance in the leg in symptomatic forefoot pes cavus: A multidisciplinary study. Foot Ankle 1992;13:489-501.

Question 16

03 A 28-year-old man underwent surgical fixation for an intra-articular distal humeral fracture 8 weeks ago now reports progressively restricted elbow motion. Radiographs at the time of union are shown in Figures 13a and 13b. Management should now consist of

Explanation

The radiographs show HO posteriorly in the triceps tendon and also anteriorly in the tendon. The fracture appears well-healed. At this point, oral indomethacin or single dose irradiation would not help as the HO is already there and these are typically used to prevent HO. Option #3 also would not help since there appears to be more of a bony block than soft tissue contracture. This leaves options 4 and 5. In the past, ectopic bone resection was
delayed until the heterotopic ossification was “mature”. This was signified by a cold bone scan and normal serum alk phos, as well as a mature appearance on xray. It was thought that by waiting until the HO was mature, recurrence would be avoided. However, in the cited reference, out of the widely read Journal of Hand Surgery, the authors obtained good results with increased range of motion, resolution of cubital tunnel syndrome and no recurrence of contractures or loss of motion with excision of ectopic bone and elbow release that was performed once bony union of fracture was obtained. They also used a 5 day course of indomethacin post-op.
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Question 17

A 13-year-old gymnast presents with ongoing knee pain for the past few months. She tried conservative measures including kinesiotaping, physical therapy and rest. On physical exam, she has normal valgus alignment, negative patellar tilt and discomfort with resisted open chain knee extension. A representative radiographs are shown in Figure A-C. What is the most likely clinical diagnosis? Review Topic

Explanation

Based on history, physical examination and radiographic findings this patient has patellofemoral syndrome
Evaluation of a patient with patellofemoral pain requires a physical examination and plain radiographs. Appropriate examination of all structures around the knee is critical to rule out other diagnoses. An MRI is useful for evaluating intra-articular or intra-osseous lesions, if clinical suspicion is suggestive of this. Treatment is predominantly conservative, with focus on low impact exercises that maximize aerobic conditioning.
Earl et al. review the epidemiology, etiology and management of patellofemoral syndrome. They note that there is no clear cause of this issue, although issues related to the quadriceps and dynamic malalignment may be contributory.
Outerbridge et al. describe overuse injuries in the young athletic patient. They provide an overview of diagnosis and management specific to this patient population.
Figures A, B and C show AP, lateral and merchant radiographs of a normal knee in a skeletally immature individual. No osseous abnormalities are identified.
Incorrect

Question 18

A 15-year-old girl has had a painful mass on the medial aspect of her left thigh for the past 5 years. The pain is present only when she is performing athletic activities and is completely relieved with rest. A radiograph and MRI scan are shown in Figures 29a and 29b. The patient and her parents would like to have the mass removed. What further diagnostic studies are required prior to considering surgical resection?

Explanation

DISCUSSION: The radiograph and MRI scan show a pedunculated lesion arising from the medial aspect of the distal femoral metaphysis. The cortex of the lesion is contiguous with the cortex of the underlying normal bone. Similarly, the medullary canal of the lesion is contiguous with that of the normal bone. These findings are diagnostic of osteochondroma. Rarely a secondary chondrosarcoma can arise in a preexisting osteochondroma. This diagnosis is suggested by identifying a cartilage cap that is greater than 1.5-cm thick in a skeletally mature patient. MRI is the best study to rule out a secondary chondrosarcoma. CT also may be used for this purpose but is not indicated in this patient because an MRI has already been obtained. A bone scan is not useful to identify a secondary chondrosarcoma. Similarly, there is no role for biopsy in this patient. No further tests are needed.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Murphey MD, Choi JJ, Kransdorf, MJ, et al: Imaging of osteochondroma: Variants and complications with radiologic-pathologic correlation. Radiographics 2000;20:1407-1434.

Question 19

Which of the following is considered an advantage of arthroscopic distal clavicle excision compared with open distal clavicle excision?

Explanation

DISCUSSION: Arthroscopic versus open distal clavicle excision has the advantage of allowing evaluation of the glenohumeral joint arthroscopically prior to moving into the subclavicular and subacromial space to perform the distal clavicle excision. This can be of value in both confirming the diagnosis as well as avoiding diagnostic errors. Berg and Ciullo showed that
in 20 patients who underwent open distal clavicle excision that resulted in failure, 15 of those patients had a superior labral anterior posterior (SLAP) lesion. Of these 15 patients who had the lesion treated surgically, 9 went on to a good to excellent result after the surgery was performed arthroscopically. Fewer complications, lower infection rate, and decreased surgical time have not been documented in the literature. Arthroscopic technique sacrifices the inferior acromioclavicular ligament and preserves the superior acromioclavicular ligament.
REFERENCES: Berg EE, Ciullo JV: The SLAP lesion: A cause of failure after distal clavicle resection. Arthroscopy 1997;13:85-89.
Lemos MJ, Tolo ET: Complications of the treatment of acromioclavicular and sternoclavicular joint injuries, including instability. Clin Sports Med 2003;22:371-385.

Question 20

A 22-year-old college baseball pitcher reports the recent onset of anterior and posterosuperior shoulder pain in his throwing shoulder. Examination shows a 15-degree loss of internal rotation, tenderness over the coracoid, and a positive relocation test. Radiographs are normal, and an MRI scan without contrast shows no definitive lesions. A rehabilitation program is prescribed. Which of the following regimens should be initially employed? Review Topic

Explanation

Throwing athletes, particularly pitchers, have a high incidence of shoulder pain. Recent evidence suggests that posteroinferior capsular tightness and scapular dyskinesis may play a substantial role in the pathologic cascade, culminating in the development of articular surface rotator cuff tears and tearing of the posterosuperior labrum. These patients have posterosuperior shoulder pain primarily. Furthermore, these athletes are susceptible to a muscular fatigue syndrome, the SICK (Scapular malposition, Inferior medial border prominence, Coracoid pain and malposition, and dysKinesis of scapular movement) scapula syndrome. This patient has an internal rotation deficit and tenderness over the coracoid. The internal rotation deficit is addressed by stretching the posterior capsule. The tenderness over the coracoid has been attributed to a contracture of the pectoralis minor tendon secondary to scapular malposition. The initial phase of the rehabilitation regimen is directed at stretching the posterior capsule and pectoralis minor tendon.

Question 21

A 52-year-old woman has a 60-degree extensor lag following a right total knee arthroplasty performed 16 months ago. Since the time of her primary total knee arthroplasty she has undergone primary repair of a patellar tendon rupture that occurred after a fall 8 months ago. A lateral radiograph of the knee is shown in Figure 52. A CT scan obtained to determine component rotation showed that the femoral component is internally rotated 9 degrees and the tibial component is internally rotated 12 degrees. Appropriate management at this time should include

Explanation

DISCUSSION: A chronic patellar tendon rupture is a difficult complication to manage. Patients typically present with both inability to extend their leg and instability of the extremity, oftentimes associated with multiple falls.
Attempts at secondary repair have been associated with high failure rates whereas the use of an extensor mechanism allograft has been shown to more effectively restore active extension in a substantial percentage of patients. Important aspects of the technique include fully tensioning the graft in full extension and immobilization of the extremity for 6 to 8 weeks postoperatively to allow for graft healing. Nonsurgical management will not result in an acceptable outcome for a young patient, and attempted secondary repair is associated with a high rate of failure, even when augmented with local tissues. This patient has gross rotational
malalignment of the components and the surgeon faced with this problem should consider obtaining a CT scan to determine component rotation preoperatively.
REFERENCES: Burnett RS, Berger RA, Paprosky WG, et al: Extensor mechanism allograft reconstruction after total knee arthroplasty: A comparison of two techniques. J Bone Joint Surg Am 2004;86:2694-2699.
Nazarian DG, Booth RE: Extensor mechanism allografts in total knee arthroplasty. Clin Orthop Relat Res
1999;367-123-129. , „. H
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Question 22

Which laboratory findings would most support a diagnosis of prosthetic joint infection (PJI) in a hip or knee arthroplasty performed 3 weeks ago?

Explanation

DISCUSSION
The diagnosis of acute PJI is associated with different criteria than the diagnosis of a chronic PJI. There is no agreed-upon threshold for ESR during the acute period (6 weeks) following total joint arthroplasty. The CRP threshold is higher during the acute period (100 mg/L vs 10 mg/L for a chronic infection). The threshold for synovial fluid analysis for an acute PJI is 10000 cells/µL and more than 90% PMN neutrophils vs 3000 cells/µL and more than 80% PMN neutrophils for a chronic infection.

Question 23

A patient with Charcot-Marie-Tooth disease has a progressively rigid cavovarus foot deformity. The patient states that the pain is restricted to the forefoot, where rigid claw toe deformities have developed. Which of the following structures is primarily involved in creation of a claw toe deformity?

Explanation

DISCUSSION: Diseases such as Charcot-Marie-Tooth result in spasticity to the extrinsic flexor tendons. This results in hyperflexion of the proximal and distal interphalangeal joints of the involved toe, as well as hyperextension at the metatarsophalangeal joint. The tendon often becomes contracted with progressive equinus of the ankle. Correction of ankle equinus exaggerates the claw toe deformity. The interosseous tendon plays no role in the etiology of a claw toe but may become contracted in later stages of the disease. Laxity of the volar plate may precipitate a claw toe deformity in a nonspastic situation. In patients with a head injury, claw toe deformities are generally the result of overactivity of the extensor tendons.
REFERENCES: Keenan MA, Gorai AP, Smith CW, Garland DE: Intrinsic toe flexion deformity following correction of spastic equinovarus deformity in adults. Foot Ankle 1987;7:333-337.
Pichney GA, Derner R, Lauf E: Digital “V” arthrodesis. J Foot Ankle Surg 1993;32:473-479.
Mizel MS, Michelson JD: Nonsurgical treatment of monarticular nontraumatic synovitis of the second metatarsophalangeal joint. Foot Ankle Int 1997;18:424-426.

Question 24

An obese 62-year-old man reports a 10-year history of progressive flatfoot deformity and a 3-month history of a painful callus along the plantar medial midfoot that has not improved with custom shoe wear, pedorthics, and callus care. There is no hindfoot motion, but functional ankle motion remains. He does not have diabetes mellitus. Radiographs are shown in Figures 27a and 27b. What is the best surgical option at this point?

Explanation

DISCUSSION: The deformity is long-standing, the hindfoot is immobile, and the radiographs reveal severe degenerative arthritis involving the entire hindfoot, severe deformity, and talonavicular dislocation. The “exostosis” responsible for the callus is the talar head; resection would severely destabilize the foot. Degenerative arthritis and fixed deformity preclude lateral column lengthening, medial slide calcaneal osteotomy, and talonavicular arthrodesis. Triple arthrodesis is the only viable option.
REFERENCES: Johnson JE, Yu JR: Arthrodesis techniques in the management of Stage II and III acquired adult flatfoot deformity. Instr Course Lect 2006;55:531-542.
Pinney SJ, Lin SS: Current concept review: Acquired adult flatfoot deformity. Foot Ankle Int 2006;27:66-75.

Question 25

Which of the following agents increases the risk for a nonunion following a posterior spinal fusion?

Explanation

DISCUSSION: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to increase the risk of pseudarthrosis. In a controlled rabbit study, nonunions were reported with the use of toradol and indomethacin. NSAIDs are commonly used medications with the potential to diminish osteogenesis. Studies clearly have demonstrated inhibition of spinal fusion following the postoperative administration of several NSAIDs, including ibuprofen. Cigarette smoking is another potent inhibitor of spinal fusion.
REFERENCES: Glassman SD, Rose SM, Dimar JR, et al: The effect of postoperative nonsteroidal anti-inflammatory drug administration on spinal fusion. Spine 1998;23:834-838.
Martin GJ Jr, Boden SD, Titus L: Recombinant human bone morphogenetic protein-2 overcomes the inhibitory effect of ketorolac, a nonsteroidal anti-inflammatory drug (NSAID), on posterolateral lumbar intertransverse process spine fusion. Spine 1999;24:2188-2193.

Question 26

below depicts the radiograph obtained from a 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 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 27

During a Lisfranc (tarsometatarsal) amputation of the foot, which of the following is crucial to prevent the patient from having a supinated foot during gait.

Explanation

DISCUSSION: A Lisfranc amputation is through the tarsometatarsal joints, except the 2nd metatarsal, which is osteotomized to preserve the stability of the medial cuneiform. To prevent the patient from supinating the foot following this amputation, the evertors on the foot must be maintained. The principal evertors are the peroneus brevis and longus (Illustration A). Therefore, the function of the peroneus brevis must be preserved. Technically this is done preserving the soft-tissue envelope (peroneus brevis, tertius and plantar fascia) around the fifth metatarsal base.
Illustration B depicts the level of a Lisfranc amputation of the foot. Incorrect Answers:
The posterior tibialis is the primary supinator of the foot, and releasing it would lead to an eversion deformity. The tibialis posterior tendon attachment to the bases of the second and third metatarsals will actually be released with this amputation, but the main attachment to the navicular preserved. 3-The anterior tibialis dorsiflexes and inverts the foot, but transferring it to the medial and middle cuneiforms would mimick its native function to dorsiflex and invert the foot. 4-A lengthened Achilles would lead to increased dorsiflexion, not supination. 5-Osteotomy of 2nd MT is crucial to preserve the medial cuneiform and midfoot stable.

Question 28

A 21-year-old college defensive lineman sustains a minimally displaced (less than 1 mm) midthird scaphoid fracture during the first game of the season. Management should consist of

Explanation

DISCUSSION: The union rate for minimally displaced midthird scaphoid fractures is quite high with cast immobilization while allowing a return to sports. Inadequate immobilization results in a much higher nonunion rate. Early fixation and rehabilitation have been proposed for sports or positions that are not amenable to cast immobilization. While immobilization of a nondisplaced fracture results in an acceptably high union rate, there is no advantage to fixation in conjunction with immobilization in the course of healing. With adequate immobilization and protection, play restrictions until healing has occurred are unnecessary.
REFERENCES: Rettig AC, Kollias SC: Internal fixation of acute stable scaphoid fractures in the athlete. Am J Sports Med 1996;24:182-186.
Rettig AC, Weidenbener EJ, Gloyeske R: Alternative management in midthird scaphoid fractures in the athlete. Am J Sports Med 1994;22:711-714.
Riester JN, Baker BE, Mosher JF, Lowe D: A review of scaphoid fracture healing in competitive athletes. Am J Sports Med 1985;13:159-161.

Question 29

-Which gene correlates with severity of disease in spinal muscular atrophy (SMA)?

Explanation

produce higher levels of SMN protein.
The other choices are not associated with spinal muscular atrophy.Defects in PMP22 are the cause of 70% to 80% of cases of Charcot-Marie-Tooth disease. Mutations in the dystrophin gene cause Duchenne muscular dystrophy.

Question 30

A 10-year-old boy twisted his ankle while skateboarding and has pain and swelling around the lateral ankle just distal to the fibula. Radiographs are obtained and a lesion is identified in the distal tibia as seen in Figures 273a and 273b. Two weeks later he has no pain to palpation in the region and denies antecedent pain. What is the most appropriate treatment for this lesion?

Explanation

Question.2 .Figures 16a and 16b are the radiographs of a 38-year-old carpenter with progressively worsening ankle pain; 14 years ago, he was involved in an all-terrain vehicle collision. Anti-inflammatory medication,corticosteroid injections, and bracing no longer effectively control his pain. The pain now interferes with his work and family responsibilities. Examination reveals an antalgic limp, varus deformity, limited ankle motion, limited eversion, and normal strength. Treatment should now consist of

ankle arthrodesis.
total ankle arthroplasty.
distal tibia osteotomy.
lateral ligament repair.
deltoid ligament release.
Question. 3 .A 48-year-old woman had total knee arthroplasty. She is unable to “lift her toes or ankle to her nose.”After 2 months of physical therapy, she has a slapping gait. What is the best next treatment step?
Ankle fusion
Ankle-foot orthosis
Sural nerve graft
Medial heel post
Laminectomy of L4/5
Question. 4 .Figures 46a through 46c are the CT scans of an 18-year-old who sustained an injury 3 weeks ago and now has ankle pain. Examination reveals an ankle effusion and painful range of motion. Recommended treatment should consist of

transtalar drilling.
fixation of the fragment.
osteochondral autograft.
weight bearing in a boot with early range of motion.
cast immobilization and nonweight-bearing activity for 6 weeks.
Question. 5 .A 47-year-old woman has a closed, displaced, Weber C bimalleolar ankle fracture. Past medical history includes diabetes mellitus for 7 years controlled with diet and an oral hypoglycemic agent. Semmes-Weinstein sensory testing reveals absence of sensation to the 5.07/10-gm monofilament on the plantar aspect of both feet. The skin is intact with 2+ pedal pulses. Treatment should include
open reduction with limited internal fixation.
closed reduction and application of an external fixator.
closed reduction and total contact cast immobilization.
retrograde intramedullary rod fixation with ankle fusion.
internal fixation and an extended period of immobilization.

Question. 6 .Figures 68a and 68b are the clinical photographs of a 55-year-old woman who had a right hindfoot fusion 3 years ago for a pes planovalgus deformity. Since the surgery, she has had lateral hindfoot pain and places most of the weight-bearing load on the lateral border of her foot when walking. What is the most likely cause of her symptoms?

Deltoid insufficiency
Excessive forefoot abduction
Residual heel valgus
Residual Achilles tendon contracture
Malposition of the transverse tarsal joint

Question 31

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

Explanation

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

Question 32

A 23-year-old male is involved in a motor vehicle accident and sustains a left open femur fracture, right open humeral shaft fracture, and an LC-II pelvic ring injury. Which of the following best describes the radiographic findings associated with this pelvic injury pattern using the Young-Burgess Classification system?

Explanation

DISCUSSION: Lateral compression type II fractures (as described by the Young-Burgess Classification System) are associated with a crescent fracture of the iliac wing located on the side of impact. A representative CT scan image and illustration of this injury are shown in Illustration A and B respectively. A table describing each pelvic injury and their associated complications is shown in Illustration C. Illustration D shows each Young-Burgess pelvic injury type.
Burgess et al discuss the effectiveness of a treatment protocol as determined by their pelvic injury classification and hemodynamic status. The injury classification system was based on lateral compression, anteroposterior compression, vertical shear, and combined mechanical injury types. They found that their classification-based treatment protocols reduce the morbidity and mortality related to pelvic ring disruption.
Tile discusses acute pelvic trauma and his classification system for pelvic injuries (ie. Types A, B, and C). He states that any classification system must be seen only as a general guide to treatment, and that the management of each patient requires careful, individualized decision making.
Incorrect
2:
This
describes
an
APC-II
injury
3:
This
describes
an
APC-III
injury
4:
This
describes
and
LC-I
injury

Question 33

In the treatment of intra-articular calcaneal fractures, surgical reduction and fixation has been shown to have improved outcomes over nonoperative treatment in all of the following patient groups EXCEPT:

Explanation

DISCUSSION: The referenced study by Buckley et al is a prospective study of intra-articular calcaneus fractures at several trauma centers. They found that overall, the outcomes after nonoperative treatment were not different from those after operative treatment. However, when stratifying groups, women who were managed operatively scored significantly higher on the SF-36 than did women who were managed nonoperatively. Also, patients who were less than twenty-nine years old, had a Böhler angle of 0 degrees to 14 degrees, a comminuted fracture, or a light workload did better after surgery compared with those who were treated nonoperatively.

Question 34

Figures 21a through 21c show the MRI scans of a 21-year-old football player who sustained a valgus knee injury while changing direction. Examination reveals swelling and tenderness along the medial aspect of the knee. There is a positive Lachman test, 3+ valgus laxity at 30 degrees, and 1+ valgus laxity at 0 degrees extension. The anterior drawer test is increased with the tibia in external rotation. The increase in the anterior drawer test with the tibia in external rotation is most likely the result of

Explanation

DISCUSSION: The injury mechanism involves a valgus load applied to the knee with the foot in external rotation. The primary stabilizer to valgus laxity is the medial collateral ligament. The secondary restraints to valgus rotation are the cruciate ligaments. Examination indicates disruption of the medial collateral and anterior cruciate ligaments. Valgus opening in extension should also arouse suspicion for an injury to the posterior cruciate ligament; however, in this patient, the valgus opening in extension is mild. The slight opening in extension and the increased anterior drawer, especially with external rotation, indicates disruption of the posteromedial capsule and posterior oblique ligament. Figure 21a shows complete disruption of the superficial and deep medial collateral ligaments involving the meniscofemoral ligament. Figure 21b shows a more posterior coronal section with a torn posterior oblique ligament. Figure 21c shows disruption of the anterior cruciate ligament, while the posterior cruciate ligament at the tibial insertion appears with a homogenous normal signal.
REFERENCES: Warren LA, Marshall JL, Girgis F: The prime static stabilizer of the medial side of the knee. J Bone Joint Surg Am 1974;56:665-674.
Indelicato PA: Injury to the medial capsuloligamentous complex of the knee, in Feagin J (ed): The Crucial Ligaments, ed 2. 1994, pp 351-360.

Question 35

03 Early failure of a unicompartmental knee arthroplasty that is the result of polyethylene wear is primarily caused by

Explanation

When components are sterilized with gamma irradiation, there is the formation of a large number of free radicals, making the polyethylene prone to oxidation and decreasing the mechanical toughness. The cited article by Engh and colleagues reported on early failure of unicompartmental knees with an all poly tibial component that had been sterilized with gamma irradiation and had a prolonged shelf life, (>4 years). All the components that were revised showed visible wear, and some were fragmented with full thickness fractures of the polyethylene. They sent the first 4 retrievals for studies of oxidation and all were found to be highly oxidized.
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Question 36

A cartilage water content increase is the hallmark of which osteoarthritis stage?

Explanation

The first stage of osteoarthritis is marked by an increase in water content secondary to disruption of the matrix framework. This is followed by an increase in chondrocyte anabolic and catabolic activity in response to tissue damage. Wnt-induced signal protein 1 increases chondrocyte protease expression. Failure to restore tissue balance ultimately leads to continued destruction and osteoarthritis. One hallmark of osteoarthritic cartilage is a reduced repair mechanism attributable to decreased chondrocyte response to growth factor stimulation (transforming growth factor-alpha and insulin-like growth factor-1). Mitochondrial dysfunction and increased production of reactive oxygen species may promote cell senescence, a progressive slowing of cellular activity. Microscopic evidence of cartilage degeneration begins with fibrillation of the superficial and transition zones, followed by disruption of the tidemark by subchondral blood vessels and eventual subchondral bone remodeling. This process ultimately leads to cartilage degradation with decreased water content in the late and terminal phases of osteoarthritis.

Question 37

A 10-year-old child has leg discomfort with activity. A radiograph, bone scan, and biopsy specimen are shown in Figures 1a through 1c. What is the most likely diagnosis?

Explanation

DISCUSSION: The ground glass appearance on the radiograph, the hot bone scan, and histologic findings of bony spicules without osteoblastic rimming in a background of bland fibrous tissue all suggest fibrous dysplasia. Stress-related pain is common with activity because of the dysplastic bone. Parosteal osteosarcomas are surface lesions. Simple cysts, aneurysmal bone cysts, and eosinophilic granuloma are all possible radiographically; however, the histology is most consistent with fibrous dysplasia.
REFERENCES: Harris WH, Dudley HR Jr, Barry RS: The natural history of fibrous dysplasia: An orthopaedic, pathological and roentgenographic study. J Bone Joint Surg Am 1962;44:207.
Campanacci M: Bone and Soft Tissue Tumors. Vienna, Austria, Springer-Verlag, 1990.

Question 38

When treating osteoporosis with alendronate, what is the most common side effect?

Explanation

DISCUSSION: Alendronate is a second-generation bisphosphonate, and it can cause epigastric distress in up to 30% of patients. This side effect can be minimized by gradually building up to therapeutic doses over a period of 4 to 8 weeks.
REFERENCES: Marshall JK, Rainsford KD, James C, et al: A randomized controlled trial to assess alendoronate-associated injury of the upper gastrointestinal tract. Aliment Pharmacol Ther 2000;14:1451-1457.
Lane JM, Sandhu HS: Osteoporosis of the spine, in Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 227-234.

Question 39

An 18-month-old boy with obstetric brachial plexus palsy is being evaluated for limited right shoulder motion. Physical therapy for the past 6 months has failed to result in improvement of the contracture. Which of the following studies is necessary prior to any shoulder reconstruction? Review Topic

Explanation

The child sustained a brachial plexus injury at birth, and internal rotation/adduction contractures frequently develop at the shoulder. Initial treatment should consist of physical therapy to increase the range of motion. If this fails, as in this patient, MRI is used to evaluate the glenohumeral joint. Commonly, there is joint deformity with increased retroversion of the glenoid and even posterior shoulder subluxation. If the deformity is mild, an anterior release, coupled with teres major and latissimus transfers, is very effective. If the deformity is severe and the shoulder is unreconstructable, then humeral derotation osteotomy is the procedure of choice. MRI of the brain, a radiograph of the elbow, and aspiration of the shoulder would not be helpful.

Question 40

Figures 2a and 2b show the radiographs of a 72-year-old man with aseptic loosening of the tibial component of his total knee arthroplasty. Optimal management should include

Explanation

DISCUSSION: The radiographs show massive subsidence of the lateral side of the tibia with severe tibial bone loss and a fractured proximal fibula. Reconstruction should consist of a large metal or bony lateral tibial augmentation, and a stem long enough to bypass the defect is required. The femoral and tibial components are articulating without any remaining polyethylene medially; therefore, the femoral component is damaged and needs revision.

The insertions of the lateral ligaments are absent, thereby rendering the lateral side of the knee predictably unstable. Also, the large valgus deformity compromises the medial collateral ligament. The posterior cruciate ligament is also likely to be deficient with this much tibial bone destruction. The patient requires a posterior stabilized femoral component at the minimum, and possibly a constrained femoral component. Retention of the femoral component, even though it may be well-fixed, jeopardizes the outcome.
REFERENCES: Lotke PA, Garino JP: Revision Total Knee Arthroplasty. New York, NY, Lippincott-Raven, 1999, pp 137-250.
Insall JN, Windsor RE, Scott WN, et al: (eds): Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 935-957.
Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000,

pp 339-365.

Question 41

What is the most likely type of pathology seen in Figure 16?

Explanation

DISCUSSION: The figure shows the missing pedicle or “winking owl” sign that is characteristic of tumor involvement of the cortical bone of the pedicle. None of the other pathologic processes commonly gives this radiographic picture. Thinned, but not missing pedicles, have been described as a normal variant.
REFERENCES: McLain R, Weinstein J: Tumors of the spine, in Herkowitz HH (ed): The Spine, ed 4. Philadelphia, PA, WB Saunders, 1992, p 1173.
Charlton OP, Martinez S, Gehweiler JA Jr: Pedicle thinning at the thoracolumbar junction: A normal variant. Am J Roentgenol 1980;134:825-826.

Question 42

A 20-year-old-man sustained a scapular fracture after attempting to grab a beam as he fell through a ceiling at a job site 3 months ago. A clinical photograph is shown in Figure 36. He now reports pain in the anterior shoulder and difficulty with overhead activities. What nerve roots make up the involved peripheral nerve?

Explanation

DISCUSSION: The patient sustained an injury to the long thoracic nerve, which supplies the serratus anterior. Branches of C5 and C6 enter the scalenus medius, unite in the muscle, and emerge as a single trunk and pass down the axilla. On the surface of the serratus anterior, the long thoracic nerve is joined by the branch from C7 and descends in front of the serratus anterior, providing segmental innervation to the serratus anterior.
REFERENCE: Leffert RD: Anatomy of the Brachial Plexus in Brachial Plexus Injuries. Churchill Livingstone, New York, NY, 1985.

Question 43

A 62-year-old woman reports diffuse aches and pains of the hip and pelvis. She denies any significant trauma but does have a history of chronic anemia. Figure 17a shows a radiograph of the pelvis, and Figures 17b and 17c show T 2 -weighted MRI scans. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiograph reveals diffuse osteopenia and areas in the proximal femora that are moth-eaten in appearance. The extent of the marrow-replacing process is evident on the MRI scans, which reveal signal abnormality throughout the entire pelvis and both proximal femora. This represents a marrow-packing process, of which multiple myeloma is the best choice. This diagnosis is also supported by the anemia noted on the patient’s history. Metastatic carcinoma and lymphoma also may have a similar presentation.
REFERENCE: Resnick D (ed): Diagnosis of Bone and Joint Disorders. Philadelphia, PA,

WB Saunders, 2002, pp 2189-2216.

Question 44

A 41-year-old woman with diabetes mellitus fell onto her outstretched arm and sustained an injury to the right elbow. Radiographs are shown in Figures 53a and 53b. What is the most appropriate management?

Explanation

The radiographs reveal a capitellum fracture with anterior displacement. To regain concentric and stable joint motion, this fragment requires reduction and stabilization. Without a joint dislocation, the ligaments are unlikely to be damaged and do not require further assessment with MRI. Closed reduction may be considered, but is unlikely to be successful. Without anatomic reduction of the fracture fragment, immobilization in either a long arm cast or a splint will not provide optimal outcomes. Based on the radiographs, the radial head is intact and does not require replacement.

Question 45

Based on the findings seen at C5-6 in Figure 30, the most likely deficit for this patient will be weakness of the

Explanation

DISCUSSION: A herniated cervical disk at C5-6 causes a C6 radiculopathy. There are eight cervical nerve roots and seven cervical vertebrae, and C8 exits between the C7 and T1 vertebrae. The C6 nerve root typically innervates the biceps and wrist extensor. The deltoid is predominantly innervated by C5. The wrist flexor and triceps are predominantly innervated by C7. Grip strength is predominantly a function of C8.
REFERENCE: Hoppenfeld S: Evaluation of nerve root lesions involving the upper extremity, in Orthopaedic Neurology. Philadelphia, PA, JB Lippincott, 1977, pp 7-23.

Question 46

A 27-year-old man sustains a Gustilo and Anderson type II open tibia fracture during a motorcycle accident. He had his full 3 doses of tetanus vaccination as an infant. He also had a tetanus booster vaccination 18 months ago when he began a new job. In addition to intravenous antibiotics, what tetanus prophylaxis should be administered?

Explanation

DISCUSSION: Any time an open wound is encountered, the tetanus prophylaxis protocol should be initiated in the emergency room. The correct treatment depends upon the severity of the wound and the patient's tetanus vaccine status. Treatment may entail no further action, vaccination, or vaccination and administration of the tetanus immune globulin. The tetanus vaccine, booster, and immune globulin are used to enhance the immune response to clostridium tetani, a gram positive bacillus found in soil. In this case, the patient's tetanus had been updated within
the past 5 years so he does not need an update of the vaccination or immune globulin. Illustration A is a concise table that can be used as an algorithm to provide appropriate tetanus prophylaxis.

Question 47

A 32-year-old woman has left second toe dactylitis (sausage toe). Radiographs show a “pencil in cup” distal interphalangeal joint deformity. Examination reveals that subtalar motion is markedly reduced. What is the most likely diagnosis?

Explanation

DISCUSSION: The patient’s clinical picture is considered the classic presentation for psoriatic arthritis. The other answers are not applicable for the constellation of findings.
REFERENCES: Jahss MH: Disorders of the Foot and Ankle, ed 2. Philadelphia, PA,

WB Saunders, 1991, pp 1691-1693.
Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 172-173.

Question 48

What percentage of bone weight is collagen?

Explanation

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

Question 49

A high school football player asks you about an oral supplement that increases body mass and improves sprint times. He would like to use it to improve performance. What is the most likely agent?

Explanation

DISCUSSION: The supplement is creatine. Approximately 17% of high school athletes and about 30% of high school football players use creatine. Creatine is a protein synthesized in the liver and the kidney, circulates in the bloodstream, and is incorporated into muscle. Its use is associated with increased muscle mass, short-term improvement in sprinting, and may allow for increased anaerobic resistance performance. Caffeine and ephedrine are taken orally but do not increase muscle mass. Testosterone and human growth hormone are both associated with increased body mass but must be injected.
REFERENCES: McGuine TA, Sullivan JC, Bernhardt DT: Creatine supplementation in high school football players. Clin J Sports Med 2001 ;11:247-253.
Rawson ES, Gunn B, Clarkson PM: The effects of creatine supplementation on exercise-induced muscle damage. J Strength Cond Res 2001; 15:178-184.
Branch JD: Effect of creatine supplementation on body composition and performance: A meta-analysis.
Int J Sport Nutr Exerc Metab 2003;13:198-226.

Question 50

A number of potential complications are associated with the direct lateral approach to the lumbar spine; which complication is most common?

Explanation

DISCUSSION
Sofianos and associates examined the cases of 45 patients who underwent the lateral transpsoas approach and found that 18 of 45 patients (40%) experienced at least 1 complication. The most common complication was postsurgical weakness of the iliopsoas, which was an issue for 10 of 45 patients (22.2%). The second-most-common complication in this series was anterior thigh hypoesthesia. This occurred in 8 of 45 patients (17.8%). A series of 600 patients by Rodgers and associates noted that thigh pain and psoas weakness following a direct lateral approach to the lumbar spine were both "nearly universal" but almost "always transient."
RECOMMENDED READINGS
Sofianos DA, Briseño MR, Abrams J, Patel AA. Complications of the lateral transpsoas approach for lumbar interbody arthrodesis: a case series and literature review. Clin Orthop Relat Res. 2012 Jun;470(6):1621-32. doi: 10.1007/s11999-011-2088-3. Review. PubMed
PMID: 21948287.View Abstract at PubMed
Lee YP, Regev GJ, Chan J, Zhang B, Taylor W, Kim CW, Garfin SR. Evaluation of hip flexion strength following lateral lumbar interbody fusion. Spine J. 2013 Oct;13(10):1259-62. doi: 10.1016/j.spinee.2013.05.031. Epub 2013 Jul 12. PubMed PMID: 23856656. View Abstract at PubMed
Rodgers WB, Gerber EJ, Patterson J. Intraoperative and early postoperative complications in extreme lateral interbody fusion: an analysis of 600 cases. Spine (Phila Pa 1976). 2011 Jan 1;36(1):26-32. doi: 10.1097/BRS.0b013e3181e1040a. PubMed PMID: 21192221. View
Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 21 AND 22
Figures 21a through 21c are the preoperative lateral standing radiograph, axial T2-weighted MR image at L4-5, and supine sagittal MR image of a 45-year-old woman who has had back and leg pain for 2 years. Treatment had included nonsteroidal anti-inflammatory drugs, physical therapy, and epidural corticosteroid injections. Her pain limited her activities of daily living; she could walk only 1 to 2 blocks before her pain became intolerable.

21A

Question 51

Varus malalignment after a talar neck fracture with medial comminution causes a decrease in what motion?

Explanation

DISCUSSION: Varus alignment at the talar neck results in a decrease in subtalar eversion before impingement occurs. Varus talar neck alignment can cause a fixed internal rotation position of the midfoot as the navicular follows the talar head. This can lead to a more rigid hindfoot which is specifically manifested as a decreased eversion range of motion.
Herscovici et al review the appropriate management of complex ankle and hindfoot injuries in this instructional course lecture.
Daniels et al performed a cadaveric study where they osteotomized the talar neck and then studied ankle motion with and without removal of a medially based wedge of bone. They found that subtalar eversion was specifically decreased.
Sanders et al found that secondary reconstructive procedures following talar neck fractures were most commonly performed to treat subtalar arthritis or misalignment.

Question 52

A 45-year-old man sustains a low-velocity gunshot wound to the base of the right thumb. The open wound is allowed to heal by secondary intention, resulting in a contracture of the first web space. Clinical photographs are shown in Figures 49a through 49c. Treatment should now consist of

Explanation

DISCUSSION: The contracture is too large for a Z-plasty, which allows a 75% increase in length. Excision of the scar with placement of a skin graft is prone to contracture. A posterior interosseous fasciocutaneous flap will provide enough well-vascularized tissue and is well suited to reach the first dorsal web space.
REFERENCES: Buchler U, Frey HP: Retrograde posterior interosseous flap. J Hand Surg Am 1991;16:283-292.
Brunelli F, Valenti P, Dumontier C, et al: The posterior interosseous reverse flap: Experience with 113 flaps. Ann Plast Surg 2001;47:25-30.

Question 53

Anterior subluxation in a throwing athlete is most commonly the result of

Explanation

DISCUSSION: Subtle anterior subluxation in the throwing athlete most frequently results from excessive capsular laxity because of repetitive microtrauma. Avulsion of the inferior glenohumeral ligament from the glenoid, or more rarely from the humerus, occurs with macrotrauma. A large Hill-Sachs lesion and a glenoid rim fracture also may result from a traumatic anterior dislocation.
REFERENCES: Kvitne RS, Jobe FW: The diagnosis and treatment of anterior instability in the throwing athlete. Clin Orthop 1993;291:107-123.
Jobe FW, Tibone JE, Jobe CM, Kvitne RS: The shoulder in sports, in Rockwood CA Jr, Matsen FA III (eds): The Shoulder, ed 2. Philadelphia, PA, WB Saunders, 1999, pp 961-990.

Question 54

A 42-year-old man sustained a burst fracture at L2 in a motor vehicle accident. Examination reveals that he is neurologically intact. Figure 18 shows a cross-sectional CT scan through the fracture. If the fracture is managed nonsurgically for the next 2 years, the retained fragments can be expected to

Explanation

DISCUSSION: Numerous articles have reported that both surgical and nonsurgical management of burst fractures are associated with resolution of impingement at long-term follow-up. If the patient is neurologically intact and appropriately treated at the time of injury, neurologic deterioration is not expected nor is there a risk of injury to the dural sac. The retained fragments can be expected to gradually resorb and widen the spinal canal.
REFERENCES: Mumford J, Weinstein JN, Spratt KF, et al: Thoracolumbar burst fractures: The clinical efficacy and outcome of nonoperative management. Spine 1993;18:955-970.
Wood KB, Butterman G, Mehbod A, et al: Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurologic deficit: A prospective, randomized study. J Bone Joint Surg Am 2003;85:773-781.

Question 55

.Figures 41a through 41c are the radiograph and MRI scans of a 76-year-old woman who has intractable left shoulder pain. She was given 2 cortisone injections and oral pain medication without experiencing lasting relief. Examination reveals 60 degrees of active forward elevation (120 degrees passively), 30 degrees of external rotation lag, and a positive Hornblower sign. Pain relief and improved functionality will most likely be achieved with

Explanation

Question 56

Figures 36a and 36b are the radiographs of a 79-year-old woman who has been experiencing increasing tibial pain 10 years after undergoing revision total knee arthroplasty. There is no evidence of infection. What is the most appropriate treatment?

Explanation

DISCUSSION
Stems are available for cemented and press-fit implantation. To be effective, press-fit stems should engage the diaphysis (Figures 36c and 36d). They also assist in obtaining correct limb alignment. Short metaphyseal-engaging stems are associated with failure rates between
16% and 29%. Cemented stems may be shorter than press-fit stems because they do not have to engage the diaphysis. Short, fully cemented stems offer the advantage of metaphyseal fixation. Hybrid stem fixation makes use of the metaphysis for cement fixation with metaphyseal cones or sleeves and diaphyseal-engaging press-fit stems.
RESPONSES FOR QUESTIONS 37 THROUGH 40
Lateral femoral cutaneous nerve
Lateral femoral circumflex artery
Superior gluteal nerve
Superior gluteal artery
Sciatic nerve
Femoral artery
Femoral vein
Femoral nerve
Saphenous branch of the femoral nerve
Profunda femoris artery
Inferior gluteal nerve
Match each description below with the anatomic structure listed above.

Question 57

A 30-year-old patient reports chronic medial knee pain and swelling. Figure 9a shows an articular cartilage lesion observed during arthroscopy. The surgeon decides to treat the lesion with the microfracture technique seen in Figure 9b. A biopsy of the repaired tissue 1 year after treatment is likely to show which of the following findings?

Explanation

DISCUSSION: Microfracture is a marrow stimulation technique where stem cells from the underlying subchondral bone marrow can form at the base of the lesion. The rationale for this technique is based on these cells differentiating into cells that will produce an articular cartilage repair. Biopsy findings in animals and humans have demonstrated primarily a fibrocartilagenous repair tissue and not articular cartilage. The collagen type found in hyaline or articular cartilage is of the type II variety. Fibrocartilage possesses mostly type I and III cartilage.
REFERENCES: Buckwalter JA, Mankin HJ: Articular cartilage: Degeneration and osteoarthritis, repair, regeneration, and transplantation. Instr Course Lect 1998;47:487-504.
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 471-488.

Question 58

Figure 11 shows the radiograph of a 3-year-old girl who sustained a proximal radius injury. Appropriate initial management should include

Explanation

DISCUSSION: The patient has a displaced radial neck fracture. Displaced radial neck fractures with angulation of more than 30° to 45° require reduction. Methods of attempted closed reduction include wrapping the arm with an Esmarch’s bandage and applying direct pressure over the maximum deformity of the radial head. More aggressive methods include a Kirschner wire used as a joystick or intramedullary reduction as described by the Metaizeau technique. Open reduction should be avoided because of complications such as stiffness or osteonecrosis. Indications for open reduction are irreducible displacement of more than 45° with severe restriction of forearm rotation.
REFERENCES: Leung AG, Peterson HA: Fractures of the proximal radial head and neck in children with emphasis on those that involve the articular cartilage. J Pediatr Orthop

2000;20:7-14.
Radomisli TE, Rosen AL: Controversies regarding radial neck fractures in children. Clin Orthop 1998;353:30-39.
Skaggs DL, Mirzayan R: The posterior fat pad sign in association with occult fracture of the elbow in children. J Bone Joint Surg Am 1999;81:1429-1433.
Gonzalez-Herranz P, Alvarez-Romera A, Burgos J, et al: Displaced radial neck fractures in children treated by closed intramedullary pinning (Metaizeau technique). J Pediatr Orthop 1997;17:325-331.

Question 59

The orthosis shown in Figure 47 is commonly used for

Explanation

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

Question 60

A 42-year-old man has a symptomatic flatfoot deformity and walks with a slight limp after falling off a scaffold 9 months ago. He also reports that he has had difficulty returning to work. Orthotics have failed to provide relief. Current radiographs are shown in Figures 19a and 19b. To relieve his pain and return the patient to work, treatment should consist of

Explanation

DISCUSSION: Because the patient has sustained a tarsometatarsal injury with midfoot sag, the treatment of choice is a tarsometatarsal arthrodesis. The cause of his flatfoot deformity is secondary to the tarsometatarsal injury and not from posterior tibialis tendon deficiency. Lateral column lengthening, double arthrodesis, and calcaneal osteotomy are not indicated. Although open reduction and internal fixation may be performed late when arthritis is present, these procedures are less likely to succeed.
REFERENCES: Komenda GA, Myerson MS, Biddinger KR: Results of arthrodesis of the tarsometatarsal joints after traumatic injury. J Bone Joint Surg Am 1996;78:1665-1676.
Sangeorzan BJ, Veith RG, Hansen ST Jr: Salvage of Lisfranc’s tarsometatarsal joint by arthrodesis. Foot Ankle 1990;10:193-200.

Question 61

Which of the following structures is most commonly involved in lateral epicondylitis?

Explanation

DISCUSSION: The most common specific site of involvement is the origin of the extensor carpi radialis brevis. It is usually caused by overuse activities, such as the eccentric overload exhibited during a backhand in tennis. In most patients, the characteristic friable, grayish tissue described as angiofibroblastic hyperplasia or hyaline degeneration is seen at the extensor carpi radialis brevis origin.
REFERENCES: Nirschl RP: Elbow tendinosis/tennis elbow. Clin Sports Med 1992;11:851-870.
Regan W, Wold LE, Coonrad R, Morrey BF: Microscopic histopathology of chronic refractory lateral epicondylitis. Am J Sports Med 1992;20:746-749.

Question 62

Which of the following clinical tests is used to diagnose medial instability of the elbow? Review Topic

Explanation

The moving valgus stress test is used in the diagnosis of medial collateral ligament instability of the elbow. The other tests apply a varus force to the elbow and are used to diagnose lateral ulnar collateral insufficiency.

Question 63

A patient has right shoulder pain. Figure 1a shows a gadolinium-enhanced transverse MRI scan at the level of the coracoid. Figure 1b shows an arthroscopic view of the anterior structures from a posterior portal. These images reveal which of the following findings?

Explanation

DISCUSSION: The area shown in the arthroscopic view and MRI scan is referred to as a Buford complex and represents a normal labral variant. It consists of a thickened, cord-like middle glenohumeral ligament, a superior labral attachment of the middle glenohumeral ligament just anterior to the biceps tendon, and absence of the anterosuperior labrum. This combination of findings can be confusing and may simulate labral pathology. Mistaken repair of the lesion back to the glenoid rim can result in significant loss of external rotation. A Bankart lesion would be located at the inferior anterior glenoid rim. The subscapularis is seen anterior to the labrum. Normal variations that occur in the anterosuperior labrum can simulate pathology.
REFERENCES: Gusmer PB, Potter HG, Schatz JA, et al: Labral injuries: Accuracy of detection with unenhanced MR imaging of the shoulder. Radiology 1996;200:519-524.
Griffin LY (ed): Orthopaedic Knowledge Update: Sports Medicine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 47-63.
Williams MM, Snyder SJ, Buford D Jr: The Buford complex: The “cord-like” middle glenohumeral ligament and absent anterosuperior labrum complex. A normal anatomic capsulolabral variant. Arthroscopy 1994;10:241-247.

Question 64

A patient is scheduled to undergo total knee arthroplasty (TKA) following failure of nonsurgical management. History reveals that she underwent a patellectomy as a teenager as the result of a motor vehicle accident. Examination reveals normal ligamentous stability. For the most predictable outcome, which of the following implants should be used?

Explanation

DISCUSSION: Paletta and Laskins performed a retrospective study of the results of TKA with cement in 22 patients who had a previous patellectomy. Nine of the patients had insertion of a posterior cruciate ligament-substituting implant. Thirteen patients had insertion of a posterior cruciate ligament-sparing implant. The 5-year postoperative knee scores were 89 for the posterior cruciate ligament-substituting knee versus 67 for the posterior cruciate

ligament-sparing knee (P < 0.01). The patella functions to increase the lever arm of the extensor mechanism and to position the quadriceps tendon and the patellar ligament roughly parallel to the anterior cruciate ligament and posterior cruciate ligament, respectively. The patellar ligament thereby provides a strong reinforcing structure that functions to prevent excessive anterior translation of the femur during flexion of the knee. The absence of the patella results in the patellar ligament and the quadriceps tendon being relatively in line with one another. After a patellectomy, the resultant quadriceps force is no longer parallel to the posterior cruciate ligament. This results in loss of the reinforcing function of the patellar ligament. The authors believe this loss of reinforcing function may place increased stresses on the posterior cruciate ligament and posterior aspect of the capsule, which may result in stretching of these structures over time. They found a high rate of anteroposterior instability, a high prevalence of recurvatum, and a high rate of loss of full active extension compared with passive extension in the posterior cruciate ligament-sparing group, which supports their theory.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 559-582.
Paletta GA Jr, Laskins RS: Total knee arthroplasty after a previous patellectomy. J Bone Joint Surg Am 1995;77:1708-1712.

Question 65

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

Explanation

DISCUSSION: Muliple neurofibromas result in marked foraminal enlargement as seen on the sagittal MRI scan. Collagen disorders leading to dural ectasia may show similar enlargement, but none of these is listed as a possible answer.
REFERENCES: Kim HW, Weinstein SL: Spine update: The management of scoliosis in neurofibromatosis. Spine 1997;22:2770-2776.
Funasaki H, Winter RB, Lonstein JB, et al: Pathophysiology of spinal deformities in neurofibromatosis: An analysis of seventy-one patients who had curves associated with dystrophic changes. J Bone Joint Surg Am 1994;76:692-700.

Question 66

A 59-year-old woman with a history of osteoporosis is involved in a high-speed motor vehicle accident, resulting in left hip pain and deformity. The initial radiograph from the trauma bay is shown in Figure 1. Postreduction CT is shown in Figures 2 through 4. What is the most appropriate definitive surgical treatment?

Explanation

DISCUSSION:
The radiograph shows a posterior wall acetabular fracture-dislocation. Post reduction CT indicates a large comminuted posterior wall fracture with marginal impaction of the articular surface. A comminuted femoral head fracture also is seen extending to the superior weight-bearing surface. Given the marginal
impaction of the acetabulum and the considerable comminution of the femoral head (which is likely unreconstructible), this injury would have a high risk of causing posttraumatic arthritis if treated with ORIF of the fractures alone. Considering this fact and the patient’s age, ORIF of the posterior wall and acute total hip arthroplasty would likely have the best functional result and the lowest risk of reoperation. Hemiarthroplasty is inappropriate for this injury considering the acetabular fracture. Skeletal traction currently plays a limited role in the definitive treatment of acetabular fractures.

Question 67

A 9-year-old girl reports the immediate onset of severe groin pain and the inability to walk after tripping on a curb. Examination reveals marked hip pain with passive range of motion. A radiograph is shown in Figure 21. Regardless of treatment, what is the most common complication following this injury?

Explanation

DISCUSSION: The patient has an unstable slipped capital femoral epiphysis (SCFE). According to the classification system based on physeal stability, an unstable SCFE is one in which the patient is unable to walk, even with crutches. Ishemic necrosis, or osteonecrosis, of the femoral head is the most devastating complication of SCFE. One study found a 47% incidence of ischemic necrosis following unstable slips. This complication is most likely the result of vascular injury associated with initial femoral head displacement rather than the result of either tamponade from joint effusion or gentle repositioning prior to stabilization. Chondrolysis is a relatively uncommon complication following treatment of SCFE. This complication has been associated with persistent penetration of the hip joint with screws or pins used to stabilize the femoral head or with spica cast immobilization. There are no reports to suggest that osteochondritis dissecans, nonunion, or coxa magna follows treatment of SCFE.
REFERENCES: Loder RT, Richards BS, Shapiro PS, et al: Acute slipped capital epiphysis: The importance of physeal stability. J Bone Joint Surg Am 1993;75:1134-1140.
Rhoad RC, Davidson RS, Heyman S, et al: Pretreatment bone scan in SCFE: A predictor of ischemia and avascular necrosis. J Pediatr Orthop 1999;19:164-168.

Question 68

Figure 17 is the radiograph of a 3-year-old girl who has shoulder pain after a fall. What is the best next step?

Explanation

CLINICAL SITUATION FOR QUESTIONS 18 THROUGH 23
Figure 18 is the lateral radiograph of the lumbar spine of an 11-year-old boy who has had lower back pain for 2 months. There is no history of injury. He denies radiating pain to his legs, numbness, weakness, and bowel or bladder changes. His usual activities include soccer practices and games 3 to 5 times per week. He has used over-the-counter anti-inflammatory medications, but has had no other treatment.

Question 69

When comparing the failure load of an evenly tensioned four-stranded hamstring tendon anterior cruciate ligament autograft to a 10-mm bone-patellar tendon-bone autograft, the hamstring graft will fail at a tension

Explanation

DISCUSSION: The failure load of an evenly tensioned four-stranded hamstring tendon autograft has been reported to be 4,500 Newtons. The failure load of a 10-mm patellar tendon autograft has been estimated at 2,600 Newtons. The intact anterior cruciate ligament failure load has been calculated at 1,725 Newtons.
REFERENCES: Corry IS, Webb JM, Clingeleffer AJ, Pinczewski LA: Arthroscopic reconstruction of the anterior cruciate ligament: A comparison of patellar tendon autograft and four-strand hamstring tendon autograft. Am J Sports Med 1999;27:448-454.
Hamner DL, Brown CH Jr, Steiner ME, et al: Hamstring tendon grafts for reconstruction of the anterior cruciate ligament: Biomechanical evaluation of the use of multiple strands and tensioning techniques. J Bone Joint Surg Am 1999;81:549-557.
Noyes FR, Butler DL, Grood ES, et al: Biomechanical analysis of human ligament grafts used in knee-ligament repairs and reconstructions. J Bone Joint Surg Am 1984;66:344-352.

Question 70

A 59-year-old active woman undergoes elective total hip replacement in which a posterior approach is used. She has minimal pain and is discharged to home 2 days after surgery. Four weeks later, she dislocates her hip while shaving her legs. She undergoes a closed reduction in the emergency department. Postreduction radiographs show a reduced hip with well-fixed components in satisfactory alignment. What is the most appropriate management of this condition from this point forward?

Explanation

DISCUSSION:
First-time early dislocations are often treated successfully without revision surgery, especially when no component malalignment is present. In this clinical scenario, it appears the patient would benefit from better education about dislocation precautions. Hip orthoses are of questionable benefit unless the patient is cognitively impaired. Revision surgery can be successful but is usually reserved for patients with recurrent dislocations.

Question 71

Figures 1 and 2 show the radiographs obtained from a 68-year-old morbidly obese man who underwent left total hip replacement 7 years ago and did well, with no symptoms prior to the current presentation. He recently rose from a seated position and felt a pop in the hip, with immediate pain and inability to bear weight. Any pressure on the left foot now produces a painful, grinding sensation with loss of left hip stability. What is the best next step?

Explanation

DISCUSSION:
The modular femoral stem has fractured. Changing the liner to a constrained design is not warranted at this time based on the information provided. Revision of the acetabular implant is appropriate because of the potential for damage to the existing cup from metal debris and femoral implant contact and to convert from a metal-on-metal articulation. Nonsurgical management would not provide pain relief or improvement; revision of the total hip arthroplasty is recommended. The implant failed in a short time, and retention of the femoral stem is not recommended because of the concern for failure with only a neck exchange. A dual-mobility bearing may be a good option if the surgeon plans to retain the acetabular component. Extended trochanteric osteotomy is a useful technique for the removal of a well-fixed femoral implant. In this patient, femoral stem removal without
osteotomy would be difficult due to the fracture of the implant’s femoral neck and the inability to gain purchase for extraction.

Question 72

The findings in Brown-Sequard syndrome include loss of which of the following? Review Topic

Explanation

Brown-Séquard syndrome is most commonly seen after penetrating injuries to the spinal cord and results in ipsilateral loss of motor function and contralateral loss of pain and temperature sensation. Patients with central cord syndrome have greater weakness in the upper extremities than in the lower extremities. Loss of proprioception is typically seen in patients with posterior cord syndrome.

Question 73

An 18-year-old man underwent open reduction and internal fixation of a tibial spine avulsion and a posterolateral corner repair. Two years later, he underwent lateral collateral ligament (LCL) and posterolateral corner reconstruction because of instability. Examination reveals a pronounced lateral varus knee thrust when ambulating. Varus stress in 30 degrees of flexion produces a 10-mm opening that is eliminated in extension. The Lachman’s test is 2 mm with a firm end point, and the posterior drawer test is negative. Standing radiographs show widening of the lateral joint space and a 5-degree mechanical varus alignment. What is the most effective course of treatment?

Explanation

DISCUSSION: The patient has chronic posterolateral instability with a varus knee alignment; therefore, the most effective treatment is a valgus-producing HTO. A repeat soft-tissue reconstruction without correction of the varus alignment will most likely fail. An ACL reconstruction is not indicated with a normal Lachman’s test. Physical therapy and bracing will have little effect.
REFERENCES: Naudie DD, Amendola A, Fowler PJ: Opening wedge high tibial osteotomy for symptomatic hyperextension-varus thrust. Am J Sports Med 2004;32:60-70.
Covey DC: Injuries of the posterolateral corner of the knee. J Bone Joint Surg Am
2001;83:106-118.

Question 74

Injury to the popliteal artery during total knee arthroplasty (TKA) is most likely to occur when placing a sharp retractor

Explanation

DISCUSSION:
Vascular complications during TKA are rare but do occur. Traditionally, it was taught that the popliteal artery was situated posterior to the PCL; however, more recent anatomic dissections have demonstrated that this artery is usually located posterolateral to the PCL.

Question 75

The strongest biomechanical construct for open reduction and internal fixation of a talar neck fracture uses what interval and entry point?

Explanation

DISCUSSION: The strongest biomechanical construct is posterior to anterior fixation with the entry point being at the level of the posterolateral tubercle of the talus. This uses the interval between the peroneus brevis and the flexor hallucis longus. The interval between the flexor digitorum longus and the flexor hallucis longus with entry at the posteromedial tubercle of the talus is not an accepted approach for fixation of talar neck fractures. All of the other options use screw placements from anterior to posterior.
REFERENCES: Swanson TV, Bray TJ, Homes GB Jr: Fractures of the talar neck: A mechanical study of fixation. J Bone Joint Surg Am 1992;74:544-551.
Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 37-38.

Question 76

A 15-year-old girl has left knee pain and an enlarging mass in the distal thigh. AP and lateral radiographs are shown in Figures 52a and 52b, and a biopsy specimen is shown in Figure 52c. What is the most likely diagnosis?

Explanation

DISCUSSION: A bone-producing lesion in the metaphysis of an adolescent is most likely an osteosarcoma. The radiographs show a distal femoral bone-producing lesion extending into the surrounding soft tissues. The histologic appearance consists of pleomorphic cells producing osteoid. Ewing’s sarcoma and metastatic neuroblastoma do not produce a matrix. Chondrosarcoma is a radiographically destructive lesion with calcification and cartilage cells on histologic section. An osteochondroma is a benign cartilage lesion that is continuous with the medullary cavity of the underlying bone and extends into a bony lesion and covered by a cartilage cap.
REFERENCES: Unni KK: Dahlin’s Bone Tumors: General Aspects and Data on 11,087 Cases, ed 5. Philadelphia, PA, Lippincott-Raven, 1996, pp 143-160.
Gibbs CP, Weber K, Scarborough MT: Malignant bone tumors. Instr Course Lect 2002;51:413-428.

Question 77

273 In an athlete who has full, painless range of motion and a normal neurological examination, which of the following is considered an absolute contraindication to participation in a collision sport such as football?

Explanation

The combination of congenital stenosis with instability, disk disease (bulge or herniation), degenerative change (osteophytes), MR imaging evidence of cord abnormality, neurologic findings lasting longer than 36 hours, or more than one recurrence is considered an absolute contraindication to sports participation. Congenital stenosis (Pavlov ratio less than 0.8) without instability is not considered a contraindication to play. Congenital anomalies of the upper cervical spine are an absolute contraindication to participation in all contact sports. This includes os odontoideum, odontoid hypoplasia or aplasia, and atlantooccipital fusion, even if asymptomatic. During play, if neurological symptoms resolve quickly and the neurologic examination is normal with full motor strength, the patient may return to the game. Persistence of symptoms or lack of a pain-free range of motion requires further evaluation, including cervical spine radiographs. Players should be restricted from further play until they have recovered full muscle strength. Cervical disk herniations can have serious permanent neurologic complications. A disk bulge without herniation as demonstrated by MR imaging, can be treated conservatively with activity modification. Return to play may occur when pain-free full range of motion is demonstrated and radicular symptoms are completely resolved. Symptomatic disk herniation with cord or root impingement may require anterior diskectomy with interbody fusion. A limited fusion (one or two levels) of the subaxial cervical spine is not considered a contraindication to future play if the segments above and below the fusion are normal. A return to play cannot be recommended until there is radiographic evidence that the graft is well incorporated, the symptoms are completely resolved, and the player demonstrates a painless range of motion and full motor strength. With the exception of spear tackler Õs spine, there is no evidence that transient neurapraxia of the cord predisposes an individual to subsequent permanent quadriplegia or quadriparesis.
Thomas BE, et al. Cervical spine injuries in football players. J AM Acad Orthop Surg 1999;7:338-347
Torg JS et al: Neurapraxia of the cervical spinal with transientquadriplegia. JBJS Am 1986:68:1354-

Question 78

What is the major difference in outcome following open reduction and internal fixation (ORIF) of the tibial plafond at 2 to 5 days versus 10 to 20 days?

Explanation

DISCUSSION: Long-term outcomes following tibial plafond fractures treated with ORIF are satisfactory in most patients despite a high incidence of posttraumatic osteoarthritis. If ORIF is delayed until 10 to 20 days following injury, the major difference in outcomes is fewer complications associated with wound healing. Ankle strength, pain, range of motion, and the development of arthritis are equal regardless of the time until fixation.
REFERENCES: Sirkin M, Sanders R, DePasquale T, et al: A staged protocol for soft tissue management in the treatment of complex pilon fractures. J Orthop Trauma 1999;13:78-84.
Pollak AN, McCarthy ML, Bess RS, et al: Outcomes after treatment of high-energy tibial plafond fractures. J Bone Joint Surg Am 2003;85:1893-1900.

Question 79

Which of the following is considered an advantage of metal femoral heads compared with ceramic heads?

Explanation

DISCUSSION: Ceramic-on-ceramic bearing surfaces have superior tribological properties and show lower linear wear than metal-on-metal implants. However, because of their lower strength and vulnerability to fracture, design considerations constrain the neck-length options available to ensure optimal taper fit.
REFERENCE: Cook SD: Materials consideration in total joint replacement, in Callaghan JJ, Dennis DA, Paprosky WG, Rosenberg AG (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1995, pp 27-33.

Question 80

Bone morphogenetic proteins transduce intracellular signal through what class of cell surface receptor?

Explanation

Bone morphogenetic proteins (BMPs) are extracellular proteins belonging to the TGF-beta superfamily of molecules. Members of this family include BMPs, growth and differentiation factors (GDFs), anti-mnllerian hormone (AMH), activin, Nodal, and TGF-beta. These proteins exert their action by binding to cell surface receptors of the serine-threonine kinase class to activate intracellular signaling pathways. The other kinase participate in various cell signaling functions, but are not associated with BMP.

Question 81

A tall, thin 17-year-old basketball player and his parents request an evaluation of his flexible (hypermobile) pes planus/planovalgus foot deformities. As part of his evaluation, the orthopaedic surgeon notes pectus excavatum, disproportionately long arms, and scoliosis. In addition to providing treatment of his feet, what test or evaluation should the patient be referred for? Review Topic

Explanation

The current diagnostic criteria for Marfan syndrome, called the Ghent criteria, are based on clinical findings and family history. The role of genetic testing in establishing the diagnosis is limited, because testing for FBN1 mutations is neither sensitive nor specific for Marfan syndrome. By making the diagnosis and arranging for cardiovascular evaluation, the orthopaedic surgeon can help prevent sudden death in these patients. The cardiovascular manifestations, including dissection and dilation of the ascending aorta and mitral valve prolapse, are responsible for nearly all of the precocious deaths of patients with Marfan syndrome. Patients with Marfan syndrome do have problems with protrusio acetabuli, scoliosis, and opthalmologic problems but the life-threatening problem that must be considered is the risk of cardiovascular sudden death.

Question 82

Surgical treatment for symptomatic disk herniations is associated with which of the following?

Explanation

DISCUSSION: The recently published SPORT trial verifies that surgical treatment of symptomatic disk herniations is associated with early and sustained pain relief. The trial also verifies that nonsurgical management is associated with improved symptoms as well. Nerve root injury, recurrent herniation, and diskitis are known complications of surgery, but all are less common than described above.
REFERENCE: Weinstein JN, Lurie JD, Tosteson TD, et al: Surgical vs nonoperative treatment for lumbar disk herniation: The Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA 2006;296:2451-2459.

Question 83

An elderly patient falls and sustains an extension injury to the neck that results in upper extremity weakness, spared perianal sensation, and lower extremity spasticity. These findings best describe what syndrome?

Explanation

DISCUSSION: These finding indicate central cord syndrome, and injury that is more common in the older population who have some degree of spondylosis. The physiologic insult can be a central spinal hematoma with resultant hematomyelia. Bowel and bladder functional return has a good prognosis, unlike the upper extremity motor loss. Cauda equina syndrome generally involves injury at the lumbar levels, with some degree of lower extremity motor loss. Posterior cord syndrome is characterized by preservation of motor function below the level of injury and position/vibratory sensory loss. Brown-Sequard syndrome, which is often produced by a penetrating injury, results in contralateral hypalgesia and ipsilateral weakness. Anterior cord syndrome has a poor prognosis for functional return; lower extremity findings include loss of light touch, sharp/dull, and temperature sensations below the level of injury, as well as

motor function.
REFERENCES: Apple DF Jr: Spinal cord injury rehabilitation, in Rothman RH, Simeone FA (eds): The Spine, ed 3. Philadelphia, PA, WB Saunders, 1992, Chapter 31.
Leventhal MR: Fractures, dislocations and fracture-dislocations of spine, in Crenshaw AH (ed): Campbell’s Operative Orthopaedics, ed 8. St. Louis, MO, Mosby, 1992.

Question 84

271 Which of the following factors has been shown to contribute to poor results after anatomic reduction of posterior wall acetabulum fractures?

Explanation

Only 30% of posterior-wall acetabular fractures involve a single large fragment. The majority are multifragmentary or have areas of impaction. Unsatisfactory clinical results occur in more than 80% of patients treated nonsurgically. Operative management usually offers the best chance of preserving long-term joint function, but only if an anatomically reconstructed acetabulum can be achieved without complication. The keys to surgical success include maintaining the viability of the fracture fragments and the femoral head itself, using bone grafts and buttress plating to support elevated and comminuted fragments, and protecting the neurovascular structures at risk.
Complications can include sciatic nerve injury (incidence, 3% to 18%), heterotopic ossification (7% to 20%), and osteonecrosis of the femoral head (5% to 8%). Despite the relative simplicity of this acetabular fracture, unsatisfactory outcomes after surgical repair of the posterior wall occur in at least 18% to 32% of cases, results that are worse than for most of the other more complex acetabular fracture patterns.
Moed BR, et al. Results of operative treatment of fractures of the posterior wall of the acetabulum. JBJS AM 2002:84:752-758
Matta JM: Fractures of the acetabulum: Accuracy of reduction and clinical results in patients managed operatively within three weeks after the injury. JBJS Am 1996;78:1632-1645
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Question 85

A 36-year-old woman is brought to the emergency department intubated and sedated following a motor vehicle accident. She is moving her upper and lower extremities spontaneously. She cannot follow commands. CT scans are shown in Figures 7a through 7c. The initial survey does not reveal any other injuries. Initial management of the cervical injury should consist of immediate Review Topic

Explanation

The patient has a bilateral facet dislocation of C6-C7 with preservation of at least some neurologic function. Urgent reduction is necessary. However, because she is sedated and unable to follow commands, an MRI scan is necessary before any closed or open posterior reduction to look for an associated disk herniation. If a disk herniation is present, it must be removed prior to any reduction maneuver to prevent iatrogenic neurologic injury. It is very unlikely that this injury can be reduced with an open anterior procedure alone.

Question 86

A 63-year-old woman with a history of poliomyelitis has a fixed 30-degree equinus contracture of the ankle, rigid hindfoot valgus, and normal knee strength and stability. She reports persistent pain and has had several medial forefoot ulcerations despite a program of stretching, bracing, and custom footwear. What is the next most appropriate step in management?

Explanation

DISCUSSION: The patient has a fixed deformity of the hindfoot and an Achilles tendon contracture; therefore, the treatment of choice is triple arthrodesis with Achilles tendon lengthening. Further bracing will not be helpful. Amputation is not indicated, and ankle arthrodesis will not address the hindfoot deformity. Palliative management would be more appropriate if the knee was unstable or the quadriceps were weak, because the equinus balances the ground reaction force across the knee.
REFERENCES: Perry J, Fontaine JD, Mulroy S: Findings in post-poliomyelitis syndrome: Weakness of muscles of the calf as a source of late pain and fatigue of muscles of the thigh after poliomyelitis. J Bone Joint Surg Am 1995;77:1148-1153.
Dehne R: Congenital and acquired neurologic disorders, in Mann RA, Coughlin MJ (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, vol 1, pp 552-553.

Question 87

A 16-year-old football player is participating in the second session of two-a-day preseason practices. He complains of dizziness and fatigue. He is brought to the sideline by the athletic trainer where examination demonstrates confusion and disorientation. Ambient temperature is 82°F. What would be the next most appropriate step in his treatment?

Explanation

Heat exhaustion and heat stroke reflect varying degrees of heat illness, with both marked by increased heat production with impaired heat dissipation. Heat exhaustion typically involves a core body temperature between 37°C (98.6°F) and 40°C (104°F) and usually presents with heavy sweating, as well as nausea; vomiting; headache; fainting; weakness; and cold or clammy skin. Fatigue, malaise, and dizziness may occur, but necessary to the diagnosis is normal mentation and stable neurologic status. Heat stroke is defined by a core body temperature >40°C (>104°F) and disturbances of the central nervous system, such as confusion, irritability, ataxia, and even coma. Heat exhaustion is a less urgent scenario and can usually be treated with rest, elevation, and rehydration. Heat stroke, confirmed here by the presence of mental status changes, is a more critical situation. The most important immediate step is rapid body cooling through whatever means are available, as this has been clearly shown to improve outcomes. Ideally, a whole body ice bath would be used, with ice towels, ice packs, cold water, and air fans all utilized if needed. Emergency department transportation and rehydration may be considered as well but are not as important as immediate lowering of body temperature. Anti-pyretics have no role in this process.

Question 88

Figures below demonstrate the radiographs obtained from a 56-year-old man with a 3-year history of right groin pain. A comprehensive nonsurgical program has failed, and the patient would like to proceed with total hip arthroplasty. He is seen by a pain management specialist and is currently taking 40 mg of sustained-release morphine twice daily with oxycodone 10 mg 2 to 3 times a day for severe pain. What is the recommended course of action regarding his chronic narcotic use?

Explanation

DISCUSSION:
Chronic opioid consumption prior to total joint arthroplasty has been associated with increased pain after surgery, increased opioid requirements, a slower recovery and longer hospital stay, and higher 90-day postoperative complications compared with patients not on chronic opioids preoperatively. Based on this information, Nguyen and associates performed a study in three patient groups that included 1) chronic opioid users who underwent no preoperative intervention, 2) chronic opioid users who were weaned down to 50% of their prior opioid regimen, and 3) patients who were not chronic opioid users. The authors found that the reduction of preoperative opioid use improved postoperative function, pain, and recovery and that the weaned group performed more like the opioid naive group than the chronic opioid user
group. Increasing opioid use prior to surgery in this patient would make it more difficult to control pain after surgery. Stopping all of his opioids just prior to surgery would place the patient at substantial risk for opioid withdrawal and is not recommended. Avoiding the use of all narcotics and using only acetaminophen postoperatively is very unlikely to provide appropriate pain relief in a chronic opioid user. The recommendation based on the provided literature is to decrease the patient's narcotic use prior to
surgery.

Question 89

..First-line treatment recommendations include

Explanation

RESPONSES FOR QUESTIONS 47 THROUGH 52
Ultrasound
MRI scan of the thigh
Chest CT scan and whole-body bone scan
Positron emission tomography (PET) scan
Presurgical radiation therapy
Marginal resection
Radical resection and postsurgical radiation
Transverse incision centered over the mass
Incision centered over the mass in line with long axis of limb
Sentinel node biopsy
Core needle biopsy
For each soft-tissue mass clinical scenario or question below, match the most appropriate next evaluation or treatment step listed above.

Question 90

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 91

What pathology is most likely to result in failure of an arthroscopic Bankart repair?

Explanation

DISCUSSION: Recent studies have documented that an arthroscopic Bankart repair performed with good technique can produce success rates similar to an open repair. However, the results of an arthroscopic repair deteriorate significantly if there is a 25% or greater anterior-inferior glenoid rim defect (inverted pear configuration) or an engaging Hill-Sachs lesion in which the humeral head defect keys onto the glenoid rim in abduction and external rotation. If either of these entities exist or there is multidirectional instability with pathologic hyperextensible tissue laxity, an open repair is recommended. An associated SLAP lesion would not significantly affect the result of the Bankart procedure. Not infrequently, the anterior glenoid labrum is partially or completely disrupted and, in itself, is not a contraindication to arthroscopic Bankart repair. In almost all patients with predominantly unidirectional instability, some degree of capsular/anterior-inferior glenohumeral ligament attenuation is present and can be addressed during the arthroscopic repair.
REFERENCES: Burkhart SS, De Beer JF: Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: Significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion. Arthroscopy 2000;16:677-694.
Cole BJ, Romeo AA: Arthroscopic shoulder stabilization with suture anchors: Technique, technology, and pitfalls. Clin Orthop 2001;390:17-30.

Question 92

A 15-year-old baseball pitcher who reports increasing pain in his right shoulder over the past 3 weeks states that the pain increases the more he pitches. Radiographs of both shoulders are shown in Figures 35a and 35b. What is the next most appropriate step in management?

Explanation

DISCUSSION: The patient has a rotational stress fracture of the proximal humeral physis (Little Leaguer’s shoulder). The symptoms of increasing pain with activity and relief with rest are typical of a stress injury. Treatment should consist of cessation of throwing activity but rehabilitation of the shoulder girdle muscles. The pitching technique should be evaluated as well.
REFERENCES: Barnett LS: Little League shoulder syndrome: Proximal humeral epiphyseolysis in the adolescent baseball pitchers: A case report. J Bone Joint Surg Am 1985;67:495-496.
Cahill BR, Tullos HS, Fain RH: Little league shoulder: Lesions of the proximal humeral epiphyseal plate. J Sports Med 1974;2:150-152.

Question 93

A 67-year-old man who underwent humeral head arthroplasty for a four-part fracture 6 months ago reports that he is still unable to actively elevate his arm. Rehabilitation after surgery consisted of a sling with passive range-of-motion exercises for 2 weeks and then progressed to active-assisted and strengthening exercises at 3 weeks. Radiographs are shown in Figures 28a and 28b. What is the primary cause of his inability to elevate the arm?

Explanation

DISCUSSION: The radiographs show nonunion of both the greater and lesser tuberosities. Tuberosity pull-off and nonunion remain among the most common causes of failed humeral head arthroplasty for fracture. Strict attention to securing the tuberosities to each other and to the shaft, and autogenous bone grafting from the excised humeral head will decrease the incidence of pull-off and improve healing rates. Active-assisted range-of-motion and strengthening exercises should be delayed until tuberosity healing is noted radiographically, usually at 6 to 8 weeks postoperatively.
REFERENCES: Hartsock LA, Estes WJ, Murray CA, et al: Shoulder hemiarthroplasty for proximal humeral fractures. Orthop Clin North Am 1998;29:467-475.
Hughes M, Neer CS: Glenohumeral joint replacement and postoperative rehabilitation.

Phys Ther 1975;55:850-858.
Compito CA, Self EB, Bigliani LU: Arthroplasty and acute shoulder trauma. Clin Orthop 1994;307:27-36.

Question 94

Which of the following is a relative contraindication to performing laminoplasty in a patient with cervical myelopathy? Review Topic

Explanation

Laminoplasty is one of the surgical options for decompressing the spinal cord in patients with cervical myelopathy. An ideal candidate is a patient with preserved cervical lordosis, as expansion of the canal relies on posterior drift of the spinal cord to achieve decompression. Posterior decompression, such as laminectomy and laminoplasty, are ideal for multilevel canal stenosis. Developed in Japan, laminoplasty is commonly performed in patients with OPLL as it avoids the dangers of working around the ossified posterior ligament. There is no age criterion for this procedure. As it is a motion-preserving procedure, 30 degrees of flexion-extension is not considered a contraindication.

Question 95

The load versus deformation curve of the functional spinal unit (FSU) is made up of the neutral zone, the elastic zone, and the plastic zone. What is the plastic zone of the curve believed to represent?

Explanation

DISCUSSION: Plastic deformation of viscoelastic tissues represents deformation of the soft tissues to the point of failure. The lining up of collagen fibers would be in the “toe region” of the curve, which, in the case of the FSU, would be mainly in the neutral zone. Elastin is a minor contributor to the composition of the ligaments and would be protected by the stiffer collagen fibers. The transition between flexion and extension occurs in the neutral zone, and reversible elongation occurs in the elastic zone.
REFERENCES: Fardon DF, Garfin SR, Abitbol J, et al (eds): Orthopaedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 15-23.
Panjabi MM, White AA: Physical properties and functional biomechanics of the spine, in White AA, Panjabi MM: Clinical Biomechanics of the Spine, ed 2. Philadelphia, PA, JB Lippincott, 1990, pp 1-83.

Question 96

Compared with surgically treated patients, patients with extra-articular distal third humeral shaft fractures that are treated nonsurgically with functional bracing can be expected to show which of the following findings?

Explanation

In a retrospective review of patients with extra-articular distal humeral shaft fractures treated surgically versus nonsurgically, the authors found that the amount of motion loss was not different between the treatment groups. Of 21 patients in the nonsurgical group, one lost 20 degrees of extension, one lost 30 degrees of extension, and one patient lost 15 degrees of flexion. Of the 19 patients in the surgical group, two patients lost 5 degrees of extension, and one each lost 10, 15, and 20 degrees of extension, respectively. One patient lost 5 degrees of flexion and one lost 15 degrees of flexion. The average loss of motion in the surgical group was 3 degrees, compared with 6 degrees in the nonsurgical group, but this difference was not significant. One hundred percent of the nonsurgically treated fractures healed. Both groups of patients regained shoulder motion within 10 degrees of normal. In the nonsurgically treated group, 10 healed with less than 10 degrees of malalignment, 6 healed with 11 to 20 degrees of malalignment, and three healed with greater than 30 degrees of malalignment, but the authors did not report any functional problems due to these deformities.

Question 97

What type of muscle contraction occurs while the muscle is lengthening?

Explanation

DISCUSSION: A muscle that lengthens as it is activated is an eccentric contraction. Isometric contraction involves no change in length. Concentric contraction occurs while the muscle is shortening. In isotonic contraction, the force remains constant through the contraction range. Isokinetic muscle contraction occurs at a constant rate of angular change of the involved joint.
REFERENCES: Garrett WE, Speer KP, Kirkendall DT (eds): Principles & Practice of Orthopaedic Sports Medicine. Philadelphia, PA, Lippincott Williams & Wilkins, 2000,

pp 12-13.
Lieber RL: Form and function of skeletal muscle, in Einhorn TA, O’Keefe RJ, Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 98

A 70-year-old woman is brought to the emergency department with a two-part greater tuberosity fracture with an anterior subcoracoid dislocation. One day after successful closed reduction, examination reveals marked swelling of the involved arm, forearm, and hand, as well as large amounts of “weeping” serous fluid but no obvious lacerations. The fingers are warm and pink, and the pulses are normal distally with good refill. Edema is present. There is no pain with passive and active motion of the elbow, wrist, and fingers. What is the next most appropriate step in management?

Explanation

DISCUSSION: Although not as common as arterial injury, venous thrombosis secondary to trauma of the subclavian or axillary vein can be problematic; therefore, venous duplex ultrasound scanning is the diagnostic study of choice. Arteriography may not show venous thrombosis in the venous run-off phase. The clinical history does not fit the usual presentation of a compartment syndrome or complex regional pain syndrome.
REFERENCE: Killewich LA, Bedford GR, Black KW, et al: Diagnosis of deep venous thrombosis: A prospective study comparing duplex scanning to contrast venography.

Circulation 1989;79:810.

Question 99

Which of the following cannulated screw configurations used in the treatment of subcapital femoral neck fractures is optimal?

Explanation

DISCUSSION: The strongest portion of the femoral neck is the posterior inferior neck in the region of the femoral calcar. The optimal biomechanical configuration includes an inverted triangle pattern with the single screw in the posterior inferior aspect of the femoral neck adjacent to the calcar.
Booth et al performed a cadaveric study comparing central versus calcar (cortical-adjacent) fixation. The results demonstrated significant improved stability, load, stiffness, and displacement in all tested parameters for the group with calcar-adjacent screw fixation.
Lindequist and Törnkvist performed a Level 4 study of 72 femoral neck fractures. They found that all 5 of their nonunions had screws placed greater than 3mm from the femoral calcar. Additionally, 16 of 18 fractures healed in the group of displaced fractures where both the fixating screws were placed within 3 mm from the femoral neck cortex.
Gurusamy et al performed a Level 4 study of 395 patients undergoing femoral neck fixation. They found a reduced spread of the screws on the lateral view was associated with an increased risk of nonunion of the fracture.
Illustration A depicts the optimal configuration of an inverted triangle with the single screw being inferior and all of the screws being cortical adjacent.

Question 100

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

Explanation

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

Full Question & Answer Text (for Search Engines)

Question 1:

Which of the following factors is associated with failure of arthroscopic excision of the distal clavicle?

Options:

Removal of less than 2 cm of bone
Male gender
Female gender
Diagnosis of osteolysis
Uneven resection of bone

Correct Answer: Uneven resection of bone

Explanation:

Question 2:

Options:

Correct Answer: L4

Explanation:

Question 3:

Options:

Quadriceps inhibition
Avulsion of the quadriceps tendon
Laceration of the patella tendon
Femoral nerve palsy

Correct Answer: Laceration of the patella tendon

Explanation:

Question 4:

If a surgeon inadvertently burrs through the midlateral wall of C5 during a anterior corpectomy, what structure is at greatest risk for injury?

Options:

C5 root
C6 root
Internal carotid artery
Vertebral artery
Vagus nerve

Correct Answer: Vertebral artery

Explanation:

DISCUSSION: The vertebral artery is contained within the vertebral foramen and thus tethered alongside the vertebral body, making it vulnerable to injury if a drill penetrates the lateral wall. The C5 root passes over the C5 pedicle and is not in the vicinity. The C6 root passes under the C5 pedicle but is posterior to the vertebral artery and is only vulnerable at the very posterior-inferior corner. The carotid artery and the vagus nerve are both within the carotid sheath and well anterior.
REFERENCES: Pfeifer BA, Freidberg SR, Jewell ER: Repair of injured vertebral artery in anterior cervical procedures. Spine 1994;19:1471-1474.
Gerszten PC, Welch WC, King JT: Quality of life assessment in patients undergoing nucleoplasty-based percutaneous discectomy. J Neurosurg Spine 2006;4:36-42.

Question 5:

Options:

an oral cephalosporin antibiotic and discharge home.
IV oxacillin and gentamicin.
arthroscopic drainage of the glenohumeral joint.
open irrigation and drainage of the glenohumeral joint.
aspiration of the glenohumeral joint and subacromial space with Gram stain and culture of the fluid.

Correct Answer: aspiration of the glenohumeral joint and subacromial space with Gram stain and culture of the fluid.

Explanation:

Question 6:

Options:

Intramedullary pinning
Bone stimulator
Sling for comfort, followed by gentle range-of-motion exercises
Open reduction and internal fixation with a plate and screws
Arthroscopic distal clavicle resection

Correct Answer: Sling for comfort, followed by gentle range-of-motion exercises

Explanation:

Question 7:

What ligament is the primary stabilizer of the wrist following a proximal row carpectomy?

Options:

Dorsal radiocarpal
Dorsal intercarpal
Radioscaphocapitate
Ulnocapitate
Ulnotriquetral

Correct Answer: Radioscaphocapitate

Explanation:

DISCUSSION: The radioscaphocapitate ligament is the prime stabilizer between the radius and capitate, preventing ulnar translocation of the carpus. Its oblique orientation prevents the carpus from drifting ulnarly. This stout ligament must be protected when excising the scaphoid.
REFERENCES: Stern PJ, Agabegi SS, Kiefhaber TR, et al: Proximal row carpectomy. J Bone Joint Surg Am 2005;87:166-174.
Wyrick JD: Proximal row carpectomy and intercarpal arthrodesis for the management of wrist arthritis. J Am Acad Orthop Surg 2003;11:227-281.

Question 8:

Options:

Patella alta
A metal-backed patella
Varus malalignment of the knee
A posterior cruciate-substituting femoral component
Lateral subluxation of the patella on a Merchant’s view

Correct Answer: A posterior cruciate-substituting femoral component

Explanation:

Question 9:

Options:

bone age of the left wrist.
MRI of the spine.
MRI of the brain.
renal and abdominal ultrasonography.
hip ultrasonography.

Correct Answer: renal and abdominal ultrasonography.

Explanation:

DISCUSSION: The patient may have Beckwith-Wiedemann syndrome (BWS), which consists of exophthalmos, macroglossia, gigantism, visceromegaly, abdominal wall defects, and neonatal hypoglycemia. Hemihypertrophy develops in approximately 15% of patients with BWS. Patients with hemihypertrophy that is the result of BWS have a 40% chance of developing malignancies such as Wilms’ tumor or hepatoblastoma; therefore, frequent ultrasound screening is recommended until about age 7 years. The absence of nevi and vascular markings helps to rule out other causes of hemihypertrophy, such as neurofibromatosis, Proteus syndrome, and Klippel-Trenaunay syndrome. Bone age estimations are not accurate at this young age but may become more useful later to help predict the timing of epiphysiodesis procedures.
REFERENCES: DeBaun MR, Tucker MA: Risk of cancer during the first four years of life in children from The Beckwith-Wiedemann Syndrome Registry. J Pediatr 1998;132:398-400.
Ballock RT, Wiesner GL, Myers MT, et al: Hemihypertrophy concepts and controversies.
J Bone Joint Surg Am 1997;79:1731-1738.
Carpenter CT, Lester EL: Skeletal age determination in young children: Analysis of three regions of the hand/wrist film. J Pediatr Orthop 1993;13:76-79.

Question 10:

When balancing gaps in the coronal plane, what structure preferentially impacts the flexion space more than the extension space?

Options:

Iliotibial band
Popliteus tendon
Lateral collateral ligament
Lateral head of the gastrocnemius

Correct Answer: Popliteus tendon

Explanation:

Question 11:

Options:

physical therapy for range of motion and strengthening following a decrease in pain and swelling.
shoulder arthroscopy for diagnosis and treatment of a possible labral tear.
open exploration and repair of a pectoralis major tendon avulsion.
MRI of the rotator cuff.
immobilization in a sling and swathe for 3 to 6 weeks, followed by mobilization and strengthening.

Correct Answer: open exploration and repair of a pectoralis major tendon avulsion.

Explanation:

Question 12:

Options:

the addition of more aggressive physiotherapy.
observation and continued non-weight-bearing.
addition of an anteriorly directed "syndesmosis screw."
loosening the syndesmotic screws from an overtightened position.
removal of screws, re-reduction of the syndesmosis, and revision fixation.

Correct Answer: removal of screws, re-reduction of the syndesmosis, and revision fixation.

Explanation:

Question 13:

Options:

Chevron osteotomy to correct hallux valgus
Custom orthosis to prevent further deformity
Observation only
Steroid injection to decrease inflammation
Extra-depth shoes

Correct Answer: Chevron osteotomy to correct hallux valgus

Explanation:

Question 14:

A patient has a humeral shaft fracture and is scheduled to undergo open reduction and internal fixation with a plate. What surgical approach will provide the greatest amount of exposure?

Options:

Modified posterior approach with elevation of the medial and lateral heads of the triceps
Posterior triceps-splitting approach
Posterior triceps-splitting approach with radial nerve mobilization
Posteromedial approach
Lateral approach with radial nerve mobilization

Correct Answer: Modified posterior approach with elevation of the medial and lateral heads of the triceps

Explanation:

DISCUSSION: The modified posterior approach with elevation of the medial and lateral heads of the triceps can provide exposure of 94% of the humeral shaft. The traditional posterior triceps-splitting approach exposes 55% of the humeral shaft.
REFERENCES: DeFranco MJ, Lawton JN: Radial nerve injuries associated with humeral fractures. J Hand Surg Am 2006;31:655-663.
Gerwin M, Hotchkiss RN, Weiland AJ: Alternative operative exposure of the posterior aspect of the humeral diaphysis with reference to the radial nerve. J Bone Joint Surg Am 1996;78:1690-1695.

Question 15:

The lower extremity motor dysfunction in Charcot-Marie-Tooth disease most commonly involves which of the following muscles?

Options:

Gastrocnemius-soleus complex
Tibialis anterior
Peroneus longus
Flexor digitorum longus
Flexor hallucis longus

Correct Answer: Tibialis anterior

Explanation:

Question 16:

Options:

oral indomethacin.
Irradiation with a single dose of 700 cGy.
Physical therapy with dynamic splinting.
Physical therapy and delayed ectopic bone excision at 12 months.
Immediate elbow release and ectopic bone excision. back answer Question 59.03

Correct Answer: Immediate elbow release and ectopic bone excision. back answer Question 59.03

Explanation:

Question 17:

Options:

Patellofemoral syndrome
Bipartite patella
Stress fracture of the distal femur
Patella alta
Patella baja

Correct Answer: Patellofemoral syndrome

Explanation:

Question 18:

Options:

Bone scan
CT
Needle biopsy
Incisional biopsy
No further tests are needed

Correct Answer: No further tests are needed

Explanation:

DISCUSSION: The radiograph and MRI scan show a pedunculated lesion arising from the medial aspect of the distal femoral metaphysis. The cortex of the lesion is contiguous with the cortex of the underlying normal bone. Similarly, the medullary canal of the lesion is contiguous with that of the normal bone. These findings are diagnostic of osteochondroma. Rarely a secondary chondrosarcoma can arise in a preexisting osteochondroma. This diagnosis is suggested by identifying a cartilage cap that is greater than 1.5-cm thick in a skeletally mature patient. MRI is the best study to rule out a secondary chondrosarcoma. CT also may be used for this purpose but is not indicated in this patient because an MRI has already been obtained. A bone scan is not useful to identify a secondary chondrosarcoma. Similarly, there is no role for biopsy in this patient. No further tests are needed.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Murphey MD, Choi JJ, Kransdorf, MJ, et al: Imaging of osteochondroma: Variants and complications with radiologic-pathologic correlation. Radiographics 2000;20:1407-1434.

Question 19:

Which of the following is considered an advantage of arthroscopic distal clavicle excision compared with open distal clavicle excision?

Options:

Fewer complications
Lower infection rate
Evaluation of the glenohumeral joint
Preservation of the inferior acromioclavicular ligament
Decreased surgical time

Correct Answer: Evaluation of the glenohumeral joint

Explanation:

Question 20:

Options:

Stretching the posterior capsule and pectoralis minor tendon
Stretching the posterior capsule and strengthening the subscapularis
Stretching the posterior capsule and using shoulder plyometrics
Stretching the anterior capsule and strengthening all components of the rotator cuff
Stretching the anterior capsule and improving pitching mechanics

Correct Answer: Stretching the posterior capsule and pectoralis minor tendon

Explanation:

Question 21:

Options:

a structured physical therapy program to increase quadriceps muscle strength.
a hinged knee brace locked in extension while ambulating.
exchange of the modular polyethylene spacer to a thicker insert and reconstruction of the patellar tendon using hamstring augmentation.
exchange of the modular polyethylene spacer to a thicker insert and reconstruction of the patellar tendon using an extensor mechanism allograft tensioned tightly in full extension.
revision of the tibial and femoral components and reconstruction of the patellar tendon using an extensor mechanism allograft tensioned tightly in full extension.

Correct Answer: revision of the tibial and femoral components and reconstruction of the patellar tendon using an extensor mechanism allograft tensioned tightly in full extension.

Explanation:

Question 22:

Which laboratory findings would most support a diagnosis of prosthetic joint infection (PJI) in a hip or knee arthroplasty performed 3 weeks ago?

Options:

Erythrocyte sedimentation rate (ESR) higher than 30 mm/h
C-reactive protein (CRP) level higher than 10 mg/L
Synovial white blood cell count higher than 10000 cells/µL
Synovial percentage of polymorphonuclear (PMN) leukocytes higher than 60%

Correct Answer: Synovial white blood cell count higher than 10000 cells/µL

Explanation:

Question 23:

Options:

Laxity of the volar plate
Intraosseous tendon
Extensor digitorum longus tendon
Extensor digitorum brevis tendon
Flexor digitorum longus tendon

Correct Answer: Flexor digitorum longus tendon

Explanation:

Question 24:

Options:

Exostectomy
Lateral column lengthening
Medial slide calcaneal osteotomy
Talonavicular arthrodesis
Triple arthrodesis

Correct Answer: Triple arthrodesis

Explanation:

DISCUSSION: The deformity is long-standing, the hindfoot is immobile, and the radiographs reveal severe degenerative arthritis involving the entire hindfoot, severe deformity, and talonavicular dislocation. The “exostosis” responsible for the callus is the talar head; resection would severely destabilize the foot. Degenerative arthritis and fixed deformity preclude lateral column lengthening, medial slide calcaneal osteotomy, and talonavicular arthrodesis. Triple arthrodesis is the only viable option.
REFERENCES: Johnson JE, Yu JR: Arthrodesis techniques in the management of Stage II and III acquired adult flatfoot deformity. Instr Course Lect 2006;55:531-542.
Pinney SJ, Lin SS: Current concept review: Acquired adult flatfoot deformity. Foot Ankle Int 2006;27:66-75.

Question 25:

Which of the following agents increases the risk for a nonunion following a posterior spinal fusion?

Options:

Ibuprofen
Intranasal calcitonin
Simvastatin
Gentamycin
Tamoxifen

Correct Answer: Ibuprofen

Explanation:

Question 26:

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 27:

During a Lisfranc (tarsometatarsal) amputation of the foot, which of the following is crucial to prevent the patient from having a supinated foot during gait.

Options:

Releasing the posterior tibialis tendon
Preserving the soft-tissue envelope (peroneus brevis, tertius and plantar fascia) around the fifth metatarsal base
Myodesis of the anterior tibialis to the medial and middle cuneiforms
Lengthening of the gastrocsoleus (achilles tendon)
Osteotomy through 1st metatarsal

Correct Answer: Releasing the posterior tibialis tendon

Explanation:

Question 28:

A 21-year-old college defensive lineman sustains a minimally displaced (less than 1 mm) midthird scaphoid fracture during the first game of the season. Management should consist of

Options:

cast immobilization and a return to play as symptoms allow.
cast immobilization and a return to play when union is achieved.
open reduction and internal fixation, followed by early range of motion with a return to play when union is achieved.
open reduction and internal fixation, followed by a return to play with protective casting.
symptomatic treatment, with definitive treatment at the end of the season.

Correct Answer: cast immobilization and a return to play as symptoms allow.

Explanation:

Question 29:

-Which gene correlates with severity of disease in spinal muscular atrophy (SMA)?

Options:

Peripheral myelin protein 22 (PMP22)
Survival motor neuron I (SMN1)
Survival motor neuron II (SMN2)
Dystrophin

Correct Answer: Survival motor neuron II (SMN2)

Explanation:

Question 30:

- A 10-year-old boy twisted his ankle while skateboarding and has pain and swelling around the lateral ankle just distal to the fibula. Radiographs are obtained and a lesion is identified in the distal tibia as seen in Figures 273a and 273b. Two weeks later he has no pain to palpation in the region and denies antecedent pain. What is the most appropriate treatment for this lesion?

Options:

Biopsy
Naprosyn
Observation
Radio frequency ablation
Curettage and bone grafting

Correct Answer: Curettage and bone grafting

Explanation:

Question.1 .A 49-year-old weekend athlete has a 4-week history of pain in his unilateral plantar heel that is most severe for the first 20 steps upon arising in the morning. He has an area of maximal tenderness on the plantar medial aspect of the heel pad at the origin of the plantar fascia. He has only improved 30% after a 3-week course of physical therapy with toe intrinsic muscle strengthening and arch- and tendo-Achilles stretching. What is the best next treatment step?
Release the plantar fascia.
Inject the plantar fascia with platelet-rich plasma.
Prescribe a night splint and continue physical therapy.
Administer extracorporeal shockwave therapy to the heel.
Perform a series of 3 steroid injections into the plantar fascia.
Question.2 .Figures 16a and 16b are the radiographs of a 38-year-old carpenter with progressively worsening ankle pain; 14 years ago, he was involved in an all-terrain vehicle collision. Anti-inflammatory medication,corticosteroid injections, and bracing no longer effectively control his pain. The pain now interferes with his work and family responsibilities. Examination reveals an antalgic limp, varus deformity, limited ankle motion, limited eversion, and normal strength. Treatment should now consist of
ankle arthrodesis.
total ankle arthroplasty.
distal tibia osteotomy.
lateral ligament repair.
deltoid ligament release.
Question. 3 .A 48-year-old woman had total knee arthroplasty. She is unable to “lift her toes or ankle to her nose.”After 2 months of physical therapy, she has a slapping gait. What is the best next treatment step?
Ankle fusion
Ankle-foot orthosis
Sural nerve graft
Medial heel post
Laminectomy of L4/5
Question. 4 .Figures 46a through 46c are the CT scans of an 18-year-old who sustained an injury 3 weeks ago and now has ankle pain. Examination reveals an ankle effusion and painful range of motion. Recommended treatment should consist of
transtalar drilling.
fixation of the fragment.
osteochondral autograft.
weight bearing in a boot with early range of motion.
cast immobilization and nonweight-bearing activity for 6 weeks.
Question. 5 .A 47-year-old woman has a closed, displaced, Weber C bimalleolar ankle fracture. Past medical history includes diabetes mellitus for 7 years controlled with diet and an oral hypoglycemic agent. Semmes-Weinstein sensory testing reveals absence of sensation to the 5.07/10-gm monofilament on the plantar aspect of both feet. The skin is intact with 2+ pedal pulses. Treatment should include
open reduction with limited internal fixation.
closed reduction and application of an external fixator.
closed reduction and total contact cast immobilization.
retrograde intramedullary rod fixation with ankle fusion.
internal fixation and an extended period of immobilization.
Question. 6 .Figures 68a and 68b are the clinical photographs of a 55-year-old woman who had a right hindfoot fusion 3 years ago for a pes planovalgus deformity. Since the surgery, she has had lateral hindfoot pain and places most of the weight-bearing load on the lateral border of her foot when walking. What is the most likely cause of her symptoms?
Deltoid insufficiency
Excessive forefoot abduction
Residual heel valgus
Residual Achilles tendon contracture
Malposition of the transverse tarsal joint

Question 31:

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

Options:

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

Correct Answer: Lumbar spinal stenosis

Explanation:

Question 32:

Options:

Crescent fracture located on the side of impact
Widened anterior SI joint, disrupted sacrotuberous and sacrospinous ligaments with intact posterior SI ligaments
Complete SI disruption with lateral displacement
Sacral compression fracture on side of impact with transverse pubic rami fractures
Open-book injury with contralateral sacral compression fracture

Correct Answer: Open-book injury with contralateral sacral compression fracture

Explanation:

Question 33:

Options:

Sedentary job
Sanders IIb fractures
Women
Younger age (<29 years old)
Previous calcaneus fracture

Correct Answer: Sedentary job

Explanation:

Question 34:

Options:

an occult fracture of the tibial plateau.
a tear of the medial collateral ligament and the posteromedial capsule.
a tear of the posterior cruciate ligament.
a tear of the anterior and posterior cruciate ligaments.
a tear of the anterior cruciate and medial collateral ligaments and the posteromedial capsule.

Correct Answer: a tear of the anterior cruciate and medial collateral ligaments and the posteromedial capsule.

Explanation:

Question 35:

03 Early failure of a unicompartmental knee arthroplasty that is the result of polyethylene wear is primarily caused by

Options:

malalignment
instability
metal backing of the tibial component
gamma irradiation sterilization and shelf storage in air 5- obesity. back answer Question 62.03

Correct Answer: gamma irradiation sterilization and shelf storage in air 5- obesity. back answer Question 62.03

Explanation:

Question 36:

A cartilage water content increase is the hallmark of which osteoarthritis stage?

Options:

Prearthritis
Early
Late
Terminal

Correct Answer: Early

Explanation:

Question 37:

A 10-year-old child has leg discomfort with activity. A radiograph, bone scan, and biopsy specimen are shown in Figures 1a through 1c. What is the most likely diagnosis?

Options:

Parosteal osteosarcoma
Unicameral bone cyst
Aneurysmal bone cyst
Eosinophilic granuloma
Fibrous dysplasia

Correct Answer: Fibrous dysplasia

Explanation:

Question 38:

When treating osteoporosis with alendronate, what is the most common side effect?

Options:

Diarrhea
Epigastric distress
Dry mucous membranes
Drowsiness
Insomnia

Correct Answer: Epigastric distress

Explanation:

Question 39:

Options:

Electromyography
MRI of the shoulder joint
MRI of the brain
Radiograph of the elbow
Aspiration of the right shoulder

Correct Answer: MRI of the shoulder joint

Explanation:

Question 40:

Figures 2a and 2b show the radiographs of a 72-year-old man with aseptic loosening of the tibial component of his total knee arthroplasty. Optimal management should include

Options:

tibial revision only, without stems or augmentations.
tibial revision only, with stems and augmentations.
revision of the tibial and femoral components, without stems or augmentations.
revision of the tibial and femoral components, with stems and augmentations.
primary arthrodesis.

Correct Answer: revision of the tibial and femoral components, with stems and augmentations.

Explanation:

DISCUSSION: The radiographs show massive subsidence of the lateral side of the tibia with severe tibial bone loss and a fractured proximal fibula. Reconstruction should consist of a large metal or bony lateral tibial augmentation, and a stem long enough to bypass the defect is required. The femoral and tibial components are articulating without any remaining polyethylene medially; therefore, the femoral component is damaged and needs revision.
The insertions of the lateral ligaments are absent, thereby rendering the lateral side of the knee predictably unstable. Also, the large valgus deformity compromises the medial collateral ligament. The posterior cruciate ligament is also likely to be deficient with this much tibial bone destruction. The patient requires a posterior stabilized femoral component at the minimum, and possibly a constrained femoral component. Retention of the femoral component, even though it may be well-fixed, jeopardizes the outcome.
REFERENCES: Lotke PA, Garino JP: Revision Total Knee Arthroplasty. New York, NY, Lippincott-Raven, 1999, pp 137-250.
Insall JN, Windsor RE, Scott WN, et al: (eds): Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 935-957.
Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000,
pp 339-365.

Question 41:

What is the most likely type of pathology seen in Figure 16?

Options:

Tumor
Infection
Inflammatory
Congenital
Trauma

Correct Answer: Tumor

Explanation:

Question 42:

Options:

C3-T1
C4-C5
C5-C7
C6-C8
C8-T1

Correct Answer: C5-C7

Explanation:

Question 43:

Options:

Chondrosarcoma
Diffuse fibrous dysplasia
Multiple myeloma
Osteoporosis
Bone infarcts

Correct Answer: Multiple myeloma

Explanation:

Question 44:

Options:

Open reduction and internal fixation
MRI of the elbow to assess the integrity of the collateral ligaments
Immobilization in a long arm cast for 3 weeks
Short-term immobilization in a splint, followed by early motion exercises
Radial head replacement

Correct Answer: Open reduction and internal fixation

Explanation:

Question 45:

Based on the findings seen at C5-6 in Figure 30, the most likely deficit for this patient will be weakness of the

Options:

deltoid.
wrist flexor.
wrist extensor.
triceps.
grip.

Correct Answer: wrist extensor.

Explanation:

Question 46:

Options:

No prophylaxis required
Tetanus vaccine
Tetanus immune globulin
Tetanus vaccine and tetanus immune globulin
Tetanus vaccine and tetanus immune globulin with a booster vaccine required 6 months from now

Correct Answer: No prophylaxis required

Explanation:

Question 47:

Options:

Rheumatoid arthritis
Lyme disease
Psoriatic arthritis
Crohn’s disease arthropathy
Gout

Correct Answer: Psoriatic arthritis

Explanation:

DISCUSSION: The patient’s clinical picture is considered the classic presentation for psoriatic arthritis. The other answers are not applicable for the constellation of findings.
REFERENCES: Jahss MH: Disorders of the Foot and Ankle, ed 2. Philadelphia, PA,
WB Saunders, 1991, pp 1691-1693.
Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 172-173.

Question 48:

What percentage of bone weight is collagen?

Options:

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

Correct Answer: 2 20% to 25%

Explanation:

Question 49:

A high school football player asks you about an oral supplement that increases body mass and improves sprint times. He would like to use it to improve performance. What is the most likely agent?

Options:

Creatine
Caffeine
Testosterone
Human growth hormone
Ephedrine

Correct Answer: Creatine

Explanation:

Question 50:

A number of potential complications are associated with the direct lateral approach to the lumbar spine; which complication is most common?

Options:

Infection
Iliopsoas weakness
Injury to the aorta
Foot drop

Correct Answer: Iliopsoas weakness

Explanation:

DISCUSSION
Sofianos and associates examined the cases of 45 patients who underwent the lateral transpsoas approach and found that 18 of 45 patients (40%) experienced at least 1 complication. The most common complication was postsurgical weakness of the iliopsoas, which was an issue for 10 of 45 patients (22.2%). The second-most-common complication in this series was anterior thigh hypoesthesia. This occurred in 8 of 45 patients (17.8%). A series of 600 patients by Rodgers and associates noted that thigh pain and psoas weakness following a direct lateral approach to the lumbar spine were both "nearly universal" but almost "always transient."
RECOMMENDED READINGS
Sofianos DA, Briseño MR, Abrams J, Patel AA. Complications of the lateral transpsoas approach for lumbar interbody arthrodesis: a case series and literature review. Clin Orthop Relat Res. 2012 Jun;470(6):1621-32. doi: 10.1007/s11999-011-2088-3. Review. PubMed
PMID: 21948287.
View Abstract at PubMed
Lee YP, Regev GJ, Chan J, Zhang B, Taylor W, Kim CW, Garfin SR. Evaluation of hip flexion strength following lateral lumbar interbody fusion. Spine J. 2013 Oct;13(10):1259-62. doi: 10.1016/j.spinee.2013.05.031. Epub 2013 Jul 12. PubMed PMID: 23856656.
View Abstract
at PubMed
Rodgers WB, Gerber EJ, Patterson J. Intraoperative and early postoperative complications in extreme lateral interbody fusion: an analysis of 600 cases. Spine (Phila Pa 1976). 2011 Jan 1;36(1):26-32. doi: 10.1097/BRS.0b013e3181e1040a. PubMed PMID: 21192221.
View
Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 21 AND 22
Figures 21a through 21c are the preoperative lateral standing radiograph, axial T2-weighted MR image at L4-5, and supine sagittal MR image of a 45-year-old woman who has had back and leg pain for 2 years. Treatment had included nonsteroidal anti-inflammatory drugs, physical therapy, and epidural corticosteroid injections. Her pain limited her activities of daily living; she could walk only 1 to 2 blocks before her pain became intolerable.
21A
B
C

Question 51:

Varus malalignment after a talar neck fracture with medial comminution causes a decrease in what motion?

Options:

Tibiotalar dorsiflexion
Tibiotalar plantarflexion
Subtalar eversion
Subtalar inversion
Internal rotation

Correct Answer: Tibiotalar dorsiflexion

Explanation:

Question 52:

Options:

Z-plasty.
a posterior interosseous fasciocutaneous flap.
a reverse cross-finger flap from the index finger.
excision of the contracture with placement of a full-thickness skin graft.
excision of the contracture with placement of a split-thickness skin graft.

Correct Answer: a posterior interosseous fasciocutaneous flap.

Explanation:

Question 53:

Anterior subluxation in a throwing athlete is most commonly the result of

Options:

avulsion of the inferior glenohumeral ligament from the glenoid.
avulsion of the inferior glenohumeral ligament from the humerus.
fracture of the anterior glenoid rim.
excessive capsular laxity from microtrauma.
a large Hill-Sachs lesion.

Correct Answer: excessive capsular laxity from microtrauma.

Explanation:

Question 54:

Options:

remain essentially unchanged in size.
result in neurologic deterioration.
gradually resorb and widen the spinal canal.
potentially migrate within the spinal canal.
increase the risk of further injury to the adjacent dural sac.

Correct Answer: gradually resorb and widen the spinal canal.

Explanation:

Question 55:

Options:

continued nonsurgical treatment.
hemiarthroplasty with partial rotator cuff repair.
reverse total shoulder arthroplasty with latissimus dorsi transfer.
rotator cuff repair without acromioplasty, preserving the coracoacromial ligament.
limited-goals debridement of the rotator cuff and glenohumeral joint without rotator cuff repair.

Correct Answer: reverse total shoulder arthroplasty with latissimus dorsi transfer.

Question 56:

Options:

Retain the components and implant a tibial strut allograft
Revise the tibial component with a metaphyseal cone and metaphyseal uncemented stem
Revise the tibial component with a metaphyseal cone and a press-fit diaphyseal-engaging stem
Revise the tibial component with a long cemented diaphyseal-engaging stem

Correct Answer: Revise the tibial component with a metaphyseal cone and a press-fit diaphyseal-engaging stem

Explanation:

Question 57:

Options:

Fibrous tissue
Bone
Articular cartilage
Fibrocartilage
Type II collagen

Correct Answer: Fibrocartilage

Explanation:

Question 58:

Figure 11 shows the radiograph of a 3-year-old girl who sustained a proximal radius injury. Appropriate initial management should include

Options:

open reduction.
closed reduction and transarticular pinning.
closed reduction.
a sling and early range of motion.
radial head excision.

Correct Answer: closed reduction.

Explanation:

DISCUSSION: The patient has a displaced radial neck fracture. Displaced radial neck fractures with angulation of more than 30° to 45° require reduction. Methods of attempted closed reduction include wrapping the arm with an Esmarch’s bandage and applying direct pressure over the maximum deformity of the radial head. More aggressive methods include a Kirschner wire used as a joystick or intramedullary reduction as described by the Metaizeau technique. Open reduction should be avoided because of complications such as stiffness or osteonecrosis. Indications for open reduction are irreducible displacement of more than 45° with severe restriction of forearm rotation.
REFERENCES: Leung AG, Peterson HA: Fractures of the proximal radial head and neck in children with emphasis on those that involve the articular cartilage. J Pediatr Orthop
2000;20:7-14.
Radomisli TE, Rosen AL: Controversies regarding radial neck fractures in children. Clin Orthop 1998;353:30-39.
Skaggs DL, Mirzayan R: The posterior fat pad sign in association with occult fracture of the elbow in children. J Bone Joint Surg Am 1999;81:1429-1433.
Gonzalez-Herranz P, Alvarez-Romera A, Burgos J, et al: Displaced radial neck fractures in children treated by closed intramedullary pinning (Metaizeau technique). J Pediatr Orthop 1997;17:325-331.

Question 59:

The orthosis shown in Figure 47 is commonly used for

Options:

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

Correct Answer: hallux rigidus.

Explanation:

Question 60:

Options:

lateral column lengthening.
open reduction and internal fixation.
double arthrodesis (talonavicular and calcaneocuboid joints).
tarsometatarsal arthrodesis.
medial displacement calcaneal osteotomy and tendon transfer.

Correct Answer: tarsometatarsal arthrodesis.

Explanation:

Question 61:

Which of the following structures is most commonly involved in lateral epicondylitis?

Options:

Anconeus
Extensor digitorum communis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris

Correct Answer: Extensor carpi radialis brevis

Explanation:

Question 62:

Which of the following clinical tests is used to diagnose medial instability of the elbow? Review Topic

Options:

Posterolateral rotatory drawer test
Lateral pivot-shift test
Moving valgus stress test
Chair test (apprehension or dislocation on terminal extension of the supinated forearm when rising from a seated position)
Pushup sign

Correct Answer: Moving valgus stress test

Explanation:

Question 63:

Options:

Normal anatomic variant (Buford complex)
Glenoid labral tear (superior labrum anterior and posterior)
Bankart lesion
Avulsion of the biceps tendon
Subscapularis tendinitis

Correct Answer: Normal anatomic variant (Buford complex)

Explanation:

Question 64:

Options:

Mobile-bearing knee
Posterior cruciate ligament-sparing knee
Posterior cruciate ligament-substituting knee
Semiconstrained-style knee
Triaxial hinged knee

Correct Answer: Posterior cruciate ligament-substituting knee

Explanation:

DISCUSSION: Paletta and Laskins performed a retrospective study of the results of TKA with cement in 22 patients who had a previous patellectomy. Nine of the patients had insertion of a posterior cruciate ligament-substituting implant. Thirteen patients had insertion of a posterior cruciate ligament-sparing implant. The 5-year postoperative knee scores were 89 for the posterior cruciate ligament-substituting knee versus 67 for the posterior cruciate
ligament-sparing knee (P < 0.01). The patella functions to increase the lever arm of the extensor mechanism and to position the quadriceps tendon and the patellar ligament roughly parallel to the anterior cruciate ligament and posterior cruciate ligament, respectively. The patellar ligament thereby provides a strong reinforcing structure that functions to prevent excessive anterior translation of the femur during flexion of the knee. The absence of the patella results in the patellar ligament and the quadriceps tendon being relatively in line with one another. After a patellectomy, the resultant quadriceps force is no longer parallel to the posterior cruciate ligament. This results in loss of the reinforcing function of the patellar ligament. The authors believe this loss of reinforcing function may place increased stresses on the posterior cruciate ligament and posterior aspect of the capsule, which may result in stretching of these structures over time. They found a high rate of anteroposterior instability, a high prevalence of recurvatum, and a high rate of loss of full active extension compared with passive extension in the posterior cruciate ligament-sparing group, which supports their theory.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 559-582.
Paletta GA Jr, Laskins RS: Total knee arthroplasty after a previous patellectomy. J Bone Joint Surg Am 1995;77:1708-1712.

Question 65:

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

Options:

Neurofibromatosis
Multiple sclerosis
Cervical spondylotic myelopathy
Acute poliomyelitis
Gaucher’s disease

Correct Answer: Neurofibromatosis

Explanation:

Question 66:

Options:

Open reduction and internal fixation (ORIF) of the acetabular fracture with concomitant acute total hip arthroplasty
ORIF of the acetabular fracture and ORIF of the femoral head fracture fragments
ORIF of the acetabular fracture and hemiarthroplasty
Skeletal traction with delayed total hip arthroplasty after the acetabular fracture has healed

Correct Answer: Open reduction and internal fixation (ORIF) of the acetabular fracture with concomitant acute total hip arthroplasty

Explanation:

Question 67:

Options:

Chondrolysis
Osteochondritis dissecans of the femoral head
Osteonecrosis of the femoral head
Nonunion
Coxa magna

Correct Answer: Osteonecrosis of the femoral head

Explanation:

Question 68:

Figure 17 is the radiograph of a 3-year-old girl who has shoulder pain after a fall. What is the best next step?

Options:

4 to 6 weeks of immobilization
Incisional biopsy followed by curettage and bone grafting
Irrigation and debridement and then antibiotics based on culture findings
Radical excision

Correct Answer: 4 to 6 weeks of immobilization

Explanation:

DISCUSSION
Patients with a pathologic fracture of a unicameral bone cyst or simple bone cyst should first pursue nonsurgical treatment and 4 to 6 weeks of immobilization. Spontaneous healing occurs in fewer than 10% of patients, possibly due to cyst decompression. The most appropriate form of surgical treatment is controversial. Many substances have been injected with variable results. Injection with steroid, bone marrow, demineralized bone matrix, and calcium phosphate/calcium sulfate have been attempted. Curettage and bone grafting and
decompression have been attempted. Indications for treatment are based on cyst size, symptoms, and location. Unicameral bone cysts typically resolve as patients reach skeletal maturity.
CLINICAL SITUATION FOR QUESTIONS 18 THROUGH 23
Figure 18 is the lateral radiograph of the lumbar spine of an 11-year-old boy who has had lower back pain for 2 months. There is no history of injury. He denies radiating pain to his legs, numbness, weakness, and bowel or bladder changes. His usual activities include soccer practices and games 3 to 5 times per week. He has used over-the-counter anti-inflammatory medications, but has had no other treatment.

Question 69:

Options:

equal to the bone-patellar tendon-bone graft.
one half the failure load of the bone-patellar tendon-bone graft.
one quarter the failure load of the bone-patellar tendon-bone graft.
approximately two times the failure load of the bone-patellar tendon-bone graft.
four times the failure load of the bone-patellar tendon-bone graft.

Correct Answer: approximately two times the failure load of the bone-patellar tendon-bone graft.

Explanation:

Question 70:

Options:

Observation and patient education regarding hip dislocation precautions
Revision to a larger-diameter femoral head
Revision to a constrained acetabular component
Application of a hip orthosis for 3 months

Correct Answer: Observation and patient education regarding hip dislocation precautions

Explanation:

Question 71:

Options:

Revision of the acetabular implant to a constrained bearing with modular exchange of the femoral head and neck
Revision of the acetabular and femoral implants
Retention of the acetabular implant with modular exchange of the femoral head and neck
Revision of the femoral component alone with a new ceramic head

Correct Answer: Revision of the acetabular and femoral implants

Explanation:

Question 72:

The findings in Brown-Sequard syndrome include loss of which of the following? Review Topic

Options:

Greater loss of upper extremity motor function than lower extremity function
Ipsilateral motor function and ipsilateral pain and temperature sensation
Ipsilateral motor function and contralateral pain and temperature sensation
Contralateral motor function and ipsilateral pain and temperature sensation
Lower of extremity proprioception and balance

Correct Answer: Ipsilateral motor function and contralateral pain and temperature sensation

Explanation:

Question 73:

Options:

Physical therapy for quadriceps strengthening
Functional bracing
Anterior cruciate ligament (ACL) reconstruction
Revision reconstruction of the LCL and posterolateral corner
Valgus-producing high tibial osteotomy (HTO)

Correct Answer: Valgus-producing high tibial osteotomy (HTO)

Explanation:

Question 74:

Injury to the popliteal artery during total knee arthroplasty (TKA) is most likely to occur when placing a sharp retractor

Options:

directly posterior to the posterior cruciate ligament (PCL).
posteromedial to the PCL.
posterolateral to the PCL.
in the posteromedial corner of the knee.

Correct Answer: posterolateral to the PCL.

Explanation:

Question 75:

The strongest biomechanical construct for open reduction and internal fixation of a talar neck fracture uses what interval and entry point?

Options:

Anterior tibialis, abductor hallucis; anteromedial head of the talus
Anterior tibialis, extensor hallucis longus; anteromedial head of the talus
Peroneus brevis, flexor hallucis longus; posterolateral tubercle of the talus
Extensor digitorum, peroneus tertius; anterolateral head of the talus
Flexor digitorum longus, flexor hallucis longus; posteromedial tubercle of the talus

Correct Answer: Peroneus brevis, flexor hallucis longus; posterolateral tubercle of the talus

Explanation:

Question 76:

Options:

Osteosarcoma
Ewing’s sarcoma
Chondrosarcoma
Metastatic neuroblastoma
Osteochondroma

Correct Answer: Osteosarcoma

Explanation:

Question 77:

Options:

A history of c4-C5 anterior discectomy and fusion
A history of spinal cord neurapraxia with transient quadriparesis that has now resolved
Os odontoideum
Congenital C5-C6 fusion
Congenital Stenosis
back answer Question 03.273

Correct Answer: Os odontoideum

Explanation:

The combination of congenital stenosis with
instability
, disk disease (bulge or herniation), degenerative change (osteophytes), MR imaging evidence of cord abnormality, neurologic findings lasting longer than 36 hours, or more than one recurrence is considered an absolute contraindication to sports participation. Congenital stenosis (Pavlov ratio less than 0.8) without instability is not considered a contraindication to play. Congenital anomalies of the upper cervical spine are an absolute contraindication to participation in all contact sports. This includes os odontoideum, odontoid hypoplasia or aplasia, and atlantooccipital fusion, even if asymptomatic. During play, if neurological symptoms resolve quickly and the neurologic examination is normal with full motor strength, the patient may return to the game. Persistence of symptoms or lack of a pain-free range of motion requires further evaluation, including cervical spine radiographs. Players should be restricted from further play until they have recovered full muscle strength. Cervical disk herniations can have serious permanent neurologic complications. A disk bulge without herniation as demonstrated by MR imaging, can be treated conservatively with activity modification. Return to play may occur when pain-free full range of motion is demonstrated and radicular symptoms are completely resolved. Symptomatic disk herniation with cord or root impingement may require anterior diskectomy with interbody fusion. A limited fusion (one or two levels) of the subaxial cervical spine is not considered a contraindication to future play if the segments above and below the fusion are normal. A return to play cannot be recommended until there is radiographic evidence that the graft is well incorporated, the symptoms are completely resolved, and the player demonstrates a painless range of motion and full motor strength. With the exception of spear tackler Õs spine, there is no evidence that transient neurapraxia of the cord predisposes an individual to subsequent permanent quadriplegia or quadriparesis.
Thomas BE, et al. Cervical spine injuries in football players. J AM Acad Orthop Surg 1999;7:338-347
Torg JS et al: Neurapraxia of the cervical spinal with transientquadriplegia. JBJS Am 1986:68:1354-

Question 78:

What is the major difference in outcome following open reduction and internal fixation (ORIF) of the tibial plafond at 2 to 5 days versus 10 to 20 days?

Options:

Improved ankle range of motion
Increased risk of wound complications
Decreased ankle pain
Decreased risk of nerve injuries
Decreased risk of development of traumatic arthritis

Correct Answer: Increased risk of wound complications

Explanation:

Question 79:

Which of the following is considered an advantage of metal femoral heads compared with ceramic heads?

Options:

Superior lubrication properties
Smoother surface
Less susceptible to third body wear
More inert material
Greater neck-length options

Correct Answer: Greater neck-length options

Explanation:

Question 80:

Bone morphogenetic proteins transduce intracellular signal through what class of cell surface receptor?

Options:

Mitogen-activated protein kinase
Tyrosine kinase
Serine-threonine kinase
Aurora kinase
Glycogen synthase kinase 3

Correct Answer: Serine-threonine kinase

Explanation:

Question 81:

Options:

Cardiovascular evaluation
Ophthalmologic evaluation
MRI of the spine
Radiographs of the hip
Genetic testing

Correct Answer: Cardiovascular evaluation

Explanation:

Question 82:

Surgical treatment for symptomatic disk herniations is associated with which of the following?

Options:

Substantial rate of nerve root injury
Early relief of pain sustained out to 2 years
Recurrent herniation rate of 35%
Outcomes that are substantially worse than nonsurgical management
10% rate of infectious diskitis

Correct Answer: Early relief of pain sustained out to 2 years

Explanation:

Question 83:

Options:

Brown-Sequard
Cauda equina
Anterior cord
Posterior cord
Central cord

Correct Answer: Central cord

Explanation:

DISCUSSION: These finding indicate central cord syndrome, and injury that is more common in the older population who have some degree of spondylosis. The physiologic insult can be a central spinal hematoma with resultant hematomyelia. Bowel and bladder functional return has a good prognosis, unlike the upper extremity motor loss. Cauda equina syndrome generally involves injury at the lumbar levels, with some degree of lower extremity motor loss. Posterior cord syndrome is characterized by preservation of motor function below the level of injury and position/vibratory sensory loss. Brown-Sequard syndrome, which is often produced by a penetrating injury, results in contralateral hypalgesia and ipsilateral weakness. Anterior cord syndrome has a poor prognosis for functional return; lower extremity findings include loss of light touch, sharp/dull, and temperature sensations below the level of injury, as well as
motor function.
REFERENCES: Apple DF Jr: Spinal cord injury rehabilitation, in Rothman RH, Simeone FA (eds): The Spine, ed 3. Philadelphia, PA, WB Saunders, 1992, Chapter 31.
Leventhal MR: Fractures, dislocations and fracture-dislocations of spine, in Crenshaw AH (ed): Campbell’s Operative Orthopaedics, ed 8. St. Louis, MO, Mosby, 1992.

Question 84:

271 Which of the following factors has been shown to contribute to poor results after anatomic reduction of posterior wall acetabulum fractures?

Options:

Marginal articular impaction
Involvement of the weight-bearing dome
Delay in reduction of hip dislocation of greater than 12 hours
Size of wall fragment
Patient age of less than 40 years
back answer Question 03.271

Correct Answer: Delay in reduction of hip dislocation of greater than 12 hours

Explanation:

Question 85:

Options:

immobilization with a halo ring and vest with reduction when medically stable.
closed traction reduction using Gardner-Wells tongs.
posterior open reduction, stabilization, and fusion.
cervical MRI followed by reduction.
anterior open reduction, stabilization, and fusion.

Correct Answer: cervical MRI followed by reduction.

Explanation:

Question 86:

Options:

CROW walker
Hyperbaric oxygen treatment
Triple arthrodesis with Achilles tendon lengthening
Transtibial amputation
Ankle arthrodesis

Correct Answer: Triple arthrodesis with Achilles tendon lengthening

Explanation:

Question 87:

Options:

Rapid cooling via ice bath, cold water and fans
Transportation via ambulance to a local emergency department
Rapid rehydration via oral and IV fluids
Immediate administration of acetaminophen or other anti-pyretics

Correct Answer: Rapid cooling via ice bath, cold water and fans

Explanation:

Question 88:

Options:

Increase his current opioid medication regimen prior to and after surgery as needed to control his pain.
Decrease his preoperative opioid use, and work with his pain management physician to decrease his postoperative opioid requirement.
Avoid using narcotics in the perioperative period to prevent overdose, and use acetaminophen only for pain control.
Stop all his opioids 5 days before surgery, and place the patient on a morphine pain control pump postoperatively with a basal rate.

Correct Answer: Decrease his preoperative opioid use, and work with his pain management physician to decrease his postoperative opioid requirement.

Explanation:

Question 89:

..First-line treatment recommendations include

Options:

synovectomy.
arthrocentesis, compressive wrap, and rest.
en bloc resection.
intra-articular radioactive nucleotide injection. DISCUSSION… The MRI scans reveal classic findings of PVNS with low signal on proton density and T2 sequences and evidence of “blooming” on gradient echo sequences. A discrete mass suggestive of a sarcoma (which would typically appear dark on T1 and bright on T2, but heterogenous and enhancing) is not seen, and synovial sarcomas rarely arise in an intra-articular location. Cartilaginous nodules of synovial chondromatosis are not seen, and the abnormal synovial process indicates that this is more than just a posttraumatic hemarthrosis. Treatment is synovectomy; radiotherapy is reserved for select recurrent cases. Arthrocentesis would be used for a simple hemarthrosis, and resection used for a sarcoma.

Correct Answer: en bloc resection.

Explanation:

Question 90:

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 91:

What pathology is most likely to result in failure of an arthroscopic Bankart repair?

Options:

A 25% or greater anterior-inferior glenoid rim defect
Nonengaging moderate Hill-Sachs defect
Associated type IV superior labrum anterior and posterior (SLAP) lesion
Absence of an intact cartilaginous labrum
Atttenuated anterior-inferior capsule and glenohumeral ligament complex

Correct Answer: A 25% or greater anterior-inferior glenoid rim defect

Explanation:

Question 92:

Options:

Increased pitching activity in conjunction with aggressive physical therapy
Biopsy of the lesion in the proximal humerus
Complete rest with no activity
Immobilization in a shoulder spica cast in the salute position
Cessation of pitching and a vigorous program of muscle strengthening

Correct Answer: Cessation of pitching and a vigorous program of muscle strengthening

Explanation:

Question 93:

Options:

Rotator cuff tear
inadequate strengthening exercises
Instability
Tuberosity nonunion
Prosthetic loosening

Correct Answer: Tuberosity nonunion

Explanation:

DISCUSSION: The radiographs show nonunion of both the greater and lesser tuberosities. Tuberosity pull-off and nonunion remain among the most common causes of failed humeral head arthroplasty for fracture. Strict attention to securing the tuberosities to each other and to the shaft, and autogenous bone grafting from the excised humeral head will decrease the incidence of pull-off and improve healing rates. Active-assisted range-of-motion and strengthening exercises should be delayed until tuberosity healing is noted radiographically, usually at 6 to 8 weeks postoperatively.
REFERENCES: Hartsock LA, Estes WJ, Murray CA, et al: Shoulder hemiarthroplasty for proximal humeral fractures. Orthop Clin North Am 1998;29:467-475.
Hughes M, Neer CS: Glenohumeral joint replacement and postoperative rehabilitation.
Phys Ther 1975;55:850-858.
Compito CA, Self EB, Bigliani LU: Arthroplasty and acute shoulder trauma. Clin Orthop 1994;307:27-36.

Question 94:

Which of the following is a relative contraindication to performing laminoplasty in a patient with cervical myelopathy? Review Topic

Options:

Ossification of the posterior longitudinal ligament (OPLL)
Cervical kyphosis measuring 20 degrees
30 degrees of sagittal mobility on flexion-extension views
Multilevel canal stenosis
Patient age older than 55 years

Correct Answer: Cervical kyphosis measuring 20 degrees

Explanation:

Question 95:

Options:

Lining up of collagen fibers within the ligaments
Stretching of elastin within the disk and ligaments
Transition between flexion and extension
Reversible elongation of the soft tissues
Traumatic range of motion, resulting in damage to the soft tissues

Correct Answer: Traumatic range of motion, resulting in damage to the soft tissues

Explanation:

Question 96:

Options:

Similar loss of elbow motion
Greater loss of elbow extension
Higher rate of varus malalignment
Higher rate of functionally limiting malalignment
Significantly better shoulder motion

Correct Answer: Similar loss of elbow motion

Explanation:

Question 97:

What type of muscle contraction occurs while the muscle is lengthening?

Options:

Isometric
Isotonic
Concentric
Isokinetic
Eccentric

Correct Answer: Eccentric

Explanation:

DISCUSSION: A muscle that lengthens as it is activated is an eccentric contraction. Isometric contraction involves no change in length. Concentric contraction occurs while the muscle is shortening. In isotonic contraction, the force remains constant through the contraction range. Isokinetic muscle contraction occurs at a constant rate of angular change of the involved joint.
REFERENCES: Garrett WE, Speer KP, Kirkendall DT (eds): Principles & Practice of Orthopaedic Sports Medicine. Philadelphia, PA, Lippincott Williams & Wilkins, 2000,
pp 12-13.
Lieber RL: Form and function of skeletal muscle, in Einhorn TA, O’Keefe RJ, Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 98:

Options:

Sympathetic stellate block
Emergent fasciotomy
Emergent arterial thrombectomy
Venous duplex ultrasound studies
Arteriography

Correct Answer: Venous duplex ultrasound studies

Explanation:

Question 99:

Which of the following cannulated screw configurations used in the treatment of subcapital femoral neck fractures is optimal?

Options:

Inverted triangle pattern with the inferior screw posterior to midline and adjacent to the calcar
Inverted triangle pattern with the inferior screw anterior to midline and adjacent to the calcar
Triangle pattern with the superior screw posterior to midline and adjacent to the calcar
Inverted triangle pattern with the inferior screw posterior to midline and central in the femoral neck
Inverted triangle pattern with the inferior screw anterior to midline and central in the femoral neck

Correct Answer: Inverted triangle pattern with the inferior screw posterior to midline and adjacent to the calcar

Explanation:

Question 100:

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

Options:

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

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

Explanation:

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

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

Orthopedic Board Review MCQs: Arthroplasty, Knee, Nerve, Shoulder & Trauma | Part 225

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 225

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index