Orthopedic Board Review MCQs (2026 Edition) - Part 10

The most likely diagnosis is osteosarcoma. The imaging studies show an aggressive primary tumor of bone, and the histology slide shows a typical chondroblastic osteosarcoma, with osteoid deposited along the surface of bone trabeculae. Ewing's sarcoma histologically consists of small round blue cells. Osteochondroma and periosteal chondroma can occur near the knee but have different radiographic and histologic patterns. Chondrosarcoma rarely occurs in children. Simon M, Springfield D, et al: Osteogenic sarcoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 267.

In a study of over 400 patients with displaced supracondylar fractures, 3.2% of the fractures were associated with the absence of the radial pulse with an otherwise well-perfused hand. Based on this study, a period of close observation with frequent neurovascular checks should be completed before attempting invasive correction of the problem. Because of the satisfactory results with expectant management, angiography, exploration, removal of fixation and exploration, and thrombectomy are contraindicated.

The hypoglossal nerve exits from the ansa cervicalis at approximately the C2-3 level and can be injured during retraction up to the C2 level. The superior laryngeal nerve lies at about C4-5. The facial nerve is much higher. The vagus nerve runs with the internal jugular and carotid much more laterally. The phrenic nerve exits posteriorly. Chang U, Lee MC, Kim DH: Anterior approach to the midcervical spine, in Kim DH, Henn JS, Vaccaro AR, et al (eds): Surgical Anatomy and Techniques to the Spine. Philadelphia, PA, Saunders Elsevier, 2006, pp 45-54.

The main function of collagen in articular cartilage is to provide the tissue's tensile strength. It also immobilizes proteoglycans within the extracellular matrix. Compressive properties are maintained by proteoglycans. Cartilage metabolism is maintained by the indwelling chondrocytes. The flow of water through the tissue promotes transport of nutrients and provides a source of lubricant for the joint. Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 3-44.

PHV generally occurs while girls are still Risser 0; menarche typically occurs before Risser 1, which has a wide variation in its timing. The curve magnitude at the PHV is the best prognostic indicator available. Most untreated patients with curves greater than 30 degrees at PHV require surgery, while patients with smaller curves at that stage typically do not require surgery. Little DG, Song KM, Katz D, Herring JA: Relationship of peak height velocity to other maturity indicators in idiopathic scoliosis in girls. J Bone Joint Surg Am 2000;82:685-693.

With a severe injury to the upper extremity, the best opportunity for achieving a good functional result for a floating elbow is immediate debridement of the open fracture, followed by internal fixation of the fractures. The ability to do this depends on the patient's physiologic status. In this patient, the procedure is acceptable because she has normal vital signs and no chest or abdominal injuries, and normal physiologic parameters (base excess and lactate) show adequate peripheral perfusion. The surgical approaches will be determined by the associated injury patterns and open wounds. In this patient, the humerus was debrided and stabilized through a posterior approach as was the medial condyle fracture. The ulna was fixed through an extension of the posterior incision and the radius through a separate dorsal approach. Solomon HB, Zadnik M, Eglseder WA: A review of outcomes in 18 patients with floating elbow. J Orthop Trauma 2003;17:563-570.

The dorsal digital cutaneous nerve of the great toe is a branch of the medial branch of the superficial peroneal nerve. The deep peroneal nerve supplies the first web space. McMinn RMH, Hutchings RT, Logan BM: Color Atlas of Foot and Ankle Anatomy. Weert, Netherlands, Wolfe Medical Publications, 1982, p 50.

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.

The patient's symptoms are typical for gouty arthropathy, and the diagnosis can only be confirmed with aspiration and visualization of the crystals. A concomitant infection also must be ruled out; therefore, it is important to obtain a cell count and culture. Colchicine may have a role in gouty management, but the diagnosis must be confirmed. Allopurinol is not effective in acute gouty arthropathy. Measurement of serum uric acid levels is often not helpful in making a definitive diagnosis. Steroid injections should be deferred until cell count and culture results indicate no accompanying infection. Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 172-173.

With the arm in the abducted, externally rotated position, the anterior band of the inferior glenohumeral ligament complex moves anteriorly, preventing anterior humeral head translation. Both the coracohumeral ligament and the superior glenohumeral ligament restrain the humeral head to inferior translation of the adducted arm, and to external rotation in the adducted position. The middle glenohumeral ligament is a primary stabilizer to anterior translation with the arm abducted to 45 degrees. The posterior band of the inferior glenohumeral ligament complex resists posterior translation of the humeral head when the arm is internally rotated. Harryman DT II, Sidles JA, Harris SL, et al: The role of the rotator interval capsule in passive motion and stability of the shoulder. J Bone Joint Surg Am 1992;74:53-66.

The most important determining factor for correction of an adult flatfoot without an arthrodesis is the flexibility of the subtalar and transverse tarsal joints. Rigid deformities cannot be corrected with a medial sliding calcaneal osteotomy with FDL transfer or a subtalar arthroereisis. Isolated subtalar or talonavicular arthrodesis does not correct the deformities entirely. If the patient has forefoot supination that can be corrected to less than 7 degrees, an isolated subtalar fusion is a possible alternative.

The patient has a significantly angulated proximal humerus fracture with a high degree of varus angulation, and rotational malalignment is likely. Failure to correct the varus angulation will result in permanent loss of shoulder abduction because the patient's age limits bony remodeling. These fractures are inherently unstable due to the inability to control the proximal fracture alignment. Shoulder spica casts have a high rate of redisplacement after treatment. Adequate open or closed reduction and pin fixation in the operating room optimizes alignment and all but eliminates the chance of redisplacement. Dobbs MB, Luhmann SJ, Gordon JE, et al: Severely displaced proximal humerus epiphyseal fractures. J Pediatr Orthop 2003;23:208-215. Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, p 701.

The tendon most prone to rupture in a patient with rheumatoid arthritis of the wrist is the extensor digiti quinti. It can be a silent injury since the extensor digitorum communis can provide extension to the fifth finger. The extensor digiti quinti is at high risk since it is overlying the ulnar head where it is prone to attritional rupture (Vaughan-Jackson syndrome). Vaughan-Jackson OJ: Rupture of extensor tendons by attrition at the inferior radioulnar joint: A report of two cases. J Bone Joint Surg Br 1948;30:528-530.

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

Although the MRI findings could be misinterpreted as an aggressive soft-tissue process, the periosteal-based ossification on the radiograph in an athlete most likely suggests myositis ossificans. The radiograph should be repeated to see further maturation of the ossification with a typical "zoning" pattern. The zoning pattern is one of peripheral ossification. This is often best seen on a CT scan. King JB: Post-traumatic ectopic calcification in the muscles of athletes: A review. Br J Sports Med 1998;32:287-290.

Displaced clavicular fractures lateral to the coracoid process (Neer type II and III) are best managed nonsurgically with sling immobilization and physical therapy, starting with pendulum exercises and progressing to active-assisted exercises when comfortable. Supervised therapy should be performed for 3 months or until full painless motion is achieved. In one study by Robinson and Cairns, this form of treatment provided patients with a 86% chance of avoiding a secondary reconstructive procedure. Robinson CM, Cairns DA: Primary nonoperative treatment of displaced lateral fractures of the clavicle. J Bone Joint Surg Am 2004;86:778-782.

Histologically, there is metaplastic cartilage arising from the synovium. These lobules of zonates hyaline cartilage are of variable size, are embedded within edematous synovium, and protrude into the joint. The lobules calcify and ossify, leading to the characteristic radiographic appearance. Inflammatory synovitis is not characteristic of synovial chondromatosis. The fluid is clear and serosanguin, not blood tinged. Milgram JM: Synovial osteochondromatosis: A histopathological study of thirty cases. J Bone Joint Surg Am 1977;l59:792-801.

Localized PVNS is a form of the disease in which synovial proliferation is restricted to one area of a joint and causes the formation of a small mass-like lesion. The true incidence of this is unknown but is probably less common than the diffuse form of the disease. PVNS presents as a usually painful discrete mass. The anterior compartment of the knee is the most common location. Tyler WK, Vidal AF, Williams RJ, et al: Pigmented villonodular synovitis. J Am Acad Orthop Surg 2006;14:376-385.

Alumina is the hardest of all the materials listed. Clinical retrieval demonstrates resistance to scratching from third-body debris.

Based on the radiographic findings, the patient has melorheostosis, a rare, benign connective tissue disorder that is characterized by a cortical thickening of bone. It produces a "dripping candle wax" appearance with dense hyperostosis that flows along the cortex. Ectopic bone formation is a consideration but is associated with injuries or burns. Bone infarcts produce intraosseous sclerosis typically affecting the distal femur with the "smoke up chimney" appearance. Infection is always a consideration but typically does not have the linear osteitis seen in melorheostosis. Juxacortical chondroma is a benign cartilage growth that arises from the capsule and may involve the underlying cortical bone but rarely the medullary canal. Campbell CJ, Papademetriou T, Bonfiglio M: Melorheostosis: A report of the clinical, roentgenographic, and pathological findings in fourteen cases. J Bone Joint Surg Am 1968;50:1281-1304.

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

An infection of the shoulder is considered a surgical emergency unless there are medical reasons that a patient cannot be taken to the operating room. If cultures of wound drainage are in question, then an aspiration should be done emergently, not several days later. The hallmark of infection in any major joint is increasing pain out of proportion to what is expected. Drainage occurring 1 to 2 days after an arthroscopic procedure is not normal, and it should be aggressively treated. Delay in diagnosis can result in sepsis and on a delayed basis, postinfectious arthritis. Both the glenohumeral joint and the subacromial space require debridement and irrigation, followed by antibiotics after both areas are cultured. Mansat P, Cofield RH, Kersten TE, Rowland CM: Complications of rotator cuff repair. Orthop Clin North Am 1997;28:205-213. Settecerri JJ, Pitner MA, Rock MG, Hanssen AD, Cofield RH: Infection after rotator cuff repair. J Shoulder Elbow Surg 1999;8:1-5. Ward WG, Eckardt JJ: Subacromial/subdeltoid bursa abscesses: An overlooked diagnosis. Clin Orthop 1993;288:189-194.

Surgical treatment is indicated for a symptomatic tarsal coalition that has failed to respond to nonsurgical management. In this patient, the radiographs reveal a calcaneonavicular coalition and no degenerative changes. The patient is symptomatic, and two attempts at use of a short leg walking cast have failed to provide relief. For calcaneonavicular coalitions, good results have been reported following resection and interposition of the extensor digitorum brevis. A retrospective study of this procedure achieved good to excellent results in 58 of 75 feet (77%). Degenerative arthritis or persistent pain following resection of a coalition is a reasonable indication for a triple arthodesis. A medial closing wedge osteotomy of the calcaneus may be indicated for a rigid flatfoot with severe valgus deformity. There are no studies documenting the long-term effectiveness of a manipulation under general anesthesia for this condition. Gonzalez P, Kumar SJ: Calcaneonavicular coalition treated by resection and interpostion of the extensor digitorum brevis muscle. J Bone Joint Surg Am 1990;72:71-77.

The patient has a nondisplaced stress fracture of the tarsal navicular. Weight bearing is associated with a high rate of nonunion; therefore, management should consist of immobilization and no weight bearing for 8 weeks. Delayed union or nonunion is treated by excision of sclerotic fracture margins and bone grafting, with or without internal fixation. Generally, CT should be repeated to document healing before permitting a return to sports. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 597-612.

The AP, obturator oblique, and iliac oblique views of the pelvis reveal a fracture that disrupts the iliopectineal and ilioischial lines, indicating a fracture that involves both anterior and posterior columns. However, it does not have the other features of anterior or posterior column fracture patterns. A displaced posterior wall fracture is also present, best seen on the obturator oblique view. The anterior to posterior directed fracture line on the CT scan indicates a transverse fracture; therefore, the patient has a transverse with posterior wall fracture pattern. A T-type fracture would be similar but would have a break into the obturator ring. Tile M: Describing the injury: Classification of acetabular fractures, in Tile M, Helfet DL, Kellam JF (eds): Fractures of the Pelvis and Acetabulum, ed 3. Philadelphia, PA, Lippincott Williams & Wilkins, 2003, pp 427-475.

Avulsion fractures of the medial epicondyle are caused by a valgus stress applied to the immature elbow and usually occur in children between the ages of 9 and 14 years. Long-term studies have shown that isolated fractures of the medial epicondyle with between 5 to 15 mm of displacement heal well. Brief immobilization (1 to 2 weeks) in a long arm cast or splint yields results similar to open reduction and internal fixation. Fibrous union of the fragment is not associated with significant symptoms or diminished function. Surgical excision of the fragment yielded the worst results in one study and should be avoided. Open reduction is best reserved for those injuries in which the medial epicondylar fragment becomes entrapped in the elbow joint during reduction and cannot be extracted by closed manipulation. Farsetti P, Potenza V, Caterini R, Ippolito E: Long-term results of treatment of fractures of the medial humeral epicondyle in children. J Bone Joint Surg Am 2001;83:1299-1305.

Patient safety and prevention of medical errors is a major focus of recent national advocacy groups. Analysis has shown that the most common sentinel event in spine surgery is surgery on the wrong level. Therefore, it is recommended that every patient have the surgical site signed, the level of surgery marked intraoperatively, and a radiograph taken. Surgery on the wrong level is most likely to occur in single-level decompressive procedures. Wong DA, Watters WC III: To err is human: Quality and safety issues in spine care. Spine 2007;32:S2-S8.

The patient has a bunionette with a large 4-5 intermetatarsal angle. This requires not only ostectomy of the lateral prominence but metatarsal osteotomy to decrease the intermetatarsal angle. Excising the head results in a flail joint and creates the possibility of a transfer lesion. Condylectomy can reduce plantar pressures but does not address the bunionette. The joint surface is well maintained, thus there are no indications for resection. Coughlin MJ: Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with distal soft tissue repair. Foot Ankle 1991;11:195-203.

Biopsy of the soft-tissue component is often diagnostic. Alternatively, in centers with pathologists familiar with bone tumors, needle biopsy is usually successful. The principles of biopsy of bone tumors include avoiding contamination of uninvolved structures and compartments, taking the most direct path to the tumors, making an excisable biopsy tract, and obtaining diagnostic tissue. Transverse biopsy incisions should be avoided because they hinder the definitive surgical procedure. Peabody TD, Simon MA: Making the diagnosis: Keys to a successful biopsy in children with bone and soft-tissue tumors. Orthop Clin North Am 1996;27:453-459. Mankin HJ, Mankin CJ, Simon MA: The hazards of the biopsy, revisited. Members of the Musculoskeletal Tumor Society. J Bone Joint Surg Am 1996;78:656-663.

The patient has an L5 radiculopathy secondary to an L4-5 disk herniation that is compressing the traversing L5 nerve root.

Federal courts have ruled that a student-athlete does not have a constitutional right to participate in athletics against medical advice. As long as the student retains his scholarship, the college is under no legal or ethical obligation to allow the student to participate in sports. A waiver would not hold up in court and would not indemnify the college or the team physician against suit. No equipment has been shown to be effective in preventing transient quadriplegia. Mathias MB: The competing demands of sport and health: An essay on the history of ethics in sports medicine. Clin Sports Med 2004;23:195-214.

Posterior capsule stretching is performed in the cross-chest and behind the back positions. Stretching in internal rotation in the abducted shoulder will further stretch the posterior capsule. Wide grip stretch, and anterior capsule and strengthening exercises will not necessarily stretch the capsule. Ellenbacher TS: Shoulder internal and external rotation strength and range of motion of highly-skilled junior tennis players. Isokinetic Exercise Sci 1992;2:1-8.

Miller and associates reported the results of a cadaveric study of the vascular risk of a posterior approach for posterior cruciate ligament reconstruction using the tibial inlay technique. The average distance from the screw to the popliteal artery was 21.1 mm (range, 18.1 mm to 31.7 mm). Other approaches, such as the transtibial tunnel technique which involves drilling an anterior-posterior tunnel, have also been studied in cadavers. Matava and associates noted that increasing flexion reduces but does not completely eliminate the risk of arterial injury during arthroscopic posterior cruciate ligament reconstruction. However, this study did not use the small, medial utility incision recommended by Fanelli and associates, which creates an interval for the surgeon's finger between the medial gastrocnemius and the posteromedial capsule so that any migration of the guidepin can be palpated and changed prior to any injury to the posterior neurovascular bundle. Matava MJ, Sethi NS, Totty WG: Proximity of the posterior cruciate ligament insertion to the popliteal artery as a function of the knee flexion angle: Implications for posterior cruciate ligament reconstruction. Arthroscopy 2000;16:796-804. Miller MD, Kline AJ, Gonzales J, et al: Vascular risk associated with posterior approach for posterior cruciate ligament reconstruction using the tibial inlay technique. J Knee Surg 2002;15:137-140.

The appropriate placement of the anterolateral portal provides access to the lateral gutter of the joint while avoiding the superficial peroneal nerve. The safest location for the portal is approximately 4 mm lateral to the peroneus tertius tendon, the closest of the tendons listed to the anterolateral portal. Because the superficial peroneal nerve location is variable, attempts to visualize, palpate, or transilluminate the nerve are mandatory.

Transfer of the flexor digitorum longus tendon is a common technique combined with other procedures to treat patients with posterior tibial tendon insufficiency. However, it is contraindicated in patients with a fixed hindfoot deformity, hypermobility, or neuromuscular compromise. It is relatively contraindicated in patients who are obese, and those older than age 60 to 70 years. Pedowitz WJ, Kovatis P: Flatfoot in the adult. J Am Acad Orthop Surg 1995;3:293-302.

Documenting the status of recovery at this time is appropriate; therefore, repeat EMG studies should be conducted to check for early signs of reinnervation. Timing of nerve exploration in this setting is debated, with authors suggesting exploration if there is no sign of recovery at 6 to 9 months. Perlmutter GS: Axillary nerve injury. Clin Orthop 1999;368:28-36. Artico M, Salvati M, D'Andrea V, et al: Isolated lesions of the axillary nerves: Surgical treatment and outcome in twelve cases. Neurosurgery 1991;29:697-700. Vissar CP, Coene LN, Brand R, et al: The incidence of nerve injury in anterior dislocation of the shoulder and its influence on functional recovery: A prospective clinical and EMG study. J Bone Joint Surg Br 1999;81:679-685.

The radiograph shows a displacement of C5 on C6 of approximately 25%. The CT scan shows a perched facet at C5-6. There is no evidence of a facet fracture. A bilateral facet dislocation would show a displacement of more than 50%. Rothman RH, Simeone FA (eds): The Spine, ed 4. Philadelphia PA, WB Saunders, 1999, pp 927-937.

For the patient with an anterior sternoclavicular dislocation, the most appropriate initial treatment should be symptomatic. Surgical options are usually contraindicated because the incidence of intraoperative and postoperative complications is high. A deformity from an anterior sternoclavicular dislocation is usually well tolerated. Return to play is allowed when symptoms resolve. Rockwood CA Jr: Disorders of the sternoclavicular joint, in Rockwood CA Jr, Matsen FA III (eds): The Shoulder. Philadelphia, PA, WB Saunders, 1998, vol 1, pp 477-525.

Distal radial physeal stress syndrome has been reported in up to 25% of nonelite gymnasts showing premature closure of the distal radial physis and distal ulnar overgrowth, producing positive ulnar variance. The diagnosis should be suspected when there is tenderness at the distal radial physis in a young gymnast. The pathology is thought to be the result of repetitive compressive stresses caused by upper extremity weight-bearing forces. The recommended treatment is 3 to 6 months of rest. Salter-Harris fractures with a distal radial epiphyseal slip are unlikely, especially in the absence of a specific traumatic event. Mandelbaum BR, Bartolozzi AR, Davis CA, Teurlings L, Bragonier B: Wrist pain syndrome in the gymnast: Pathogenetic, diagnostic, and therapeutic consideration. Am J Sports Med 1989;17:305-317.

The radiographs show an elbow dislocation associated with a comminuted radial head fracture. In the setting of comminution and instability, factures of the radial head are best managed with an arthroplasty rather than open reduction and internal fixation. Resection of the radial head will worsen the instability and is not recommended. Silastic radial head replacements are contraindicated. Hildebrand KA, Patterson SD, King GJ: Acute elbow dislocations: Simple and complex. Orthop Clin North Am 1999;30:63-79.

Some patients have minimal symptoms associated with hallux rigidus despite significant radiographic evidence of osteoarthritis. This patient's symptoms are primarily related to shoe pressure from the exostosis and can be managed with extra-depth shoe wear. Smith RW, Katchis SD, Ayson LC: Outcomes in hallux rigidus patients treated nonoperatively: A long-term follow-up study. Foot Ankle Int 2000;21:906-913.

Placing cement over a bone biopsy site prevents tumor contamination by controlling hematoma. Even though the use of cement may impart some strength, the femur is still at significant risk for fracture. The use of bone cement in this manner has not been cleared by the FDA, but many physicians feel that it is appropriate when the patient's health status has been given careful consideration, and the physician has the necessary knowledge and training. The other options are not important reasons to use methylmethacrylate in biopsies. Simon MA, Springfield DS, et al: Biopsy: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, pp 55-65.

The musculocutaneous nerve travels through the conjoined tendon approximately 8 cm distal to the tip of the acromion. The musculocutaneous nerve innervates the biceps muscle and the bracialis muscle, both of which are responsible for elbow flexion. Shoulder flexion is facilitated by the anterior fibers of the deltoid muscle (axillary nerve) and the supraspinatus muscle (suprascapular nerve). The subscapular muscle facilitates internal rotation of the shoulder (upper and lower subscapularis nerve). Shoulder abduction is performed by the deltoid muscle (axillary nerve), and forearm pronation is facilitated by the pronator teres (median nerve). Hollinshead WH: Anatomy for Surgeons: The Back and Limbs, ed 3. Philadelphia, PA, Harper and Row, 1982, pp 391-393.

There is no identifiable thoracic, abdominal, or long bone source of ongoing bleeding. The patient has a lateral compression Burgess-Young type I pelvic ring injury. This injury does not increase the pelvic volume because it is not unstable in external rotation. Application of a PASG, a pelvic clamp, or an external fixator may be helpful if the patient has a pelvic injury that is unstable in external rotation or translation but would be of little use in this injury pattern. Persistent hemodynamic instability after administration of 4 units of blood is the decision point where most authors would recommend angiography and embolization. If the pelvis is unstable in external rotation or translation, inflation of the PASG trousers or application of an external fixator is recommended before angiography. Attributing the hemodynamic instability to the head injury before ruling out the pelvis as a source is not indicated. Burgess AR, Eastridge BJ, Young JW, et al: Pelvic ring disruptions: Effective classification system and treatment protocols. J Trauma 1990;30:848-856. Evers BM, Cryer HM, Miller FB: Pelvic fracture hemorrhage: Priorities in management. Arch Surg 1989;124:422-424.

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. 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.

Four years after surgery, more than 90% of patients are satisfied with the cosmetic appearance of the iliac donor site scar. Approximately 25% still have pain and/or functional difficulty, including 12.7% who still report difficulty with ambulation, 11.9% difficulty with recreational activities, 7.5% with sexual intercourse, and 11.2% require pain medication for iliac donor site symptoms. Silber JS, Anderson DG, Daffner SD, et al: Donor site morbidity after anterior iliac crest bone harvest for single-level anterior cervical discectomy and fusion. Spine 2003;28:134-139.

The term 'spinal shock' applies to all phenomena surrounding physiologic or anatomic transection of the spinal cord that results in temporary loss or depression of all or most spinal reflex activity below the level of the injury. Hypotension and bradycardia caused by loss of sympathetic tone is a possible complication, depending on the level of the lesion. The mechanism of injury that causes spinal shock is usually traumatic in origin and occurs immediately, but spinal shock has been described with mechanisms of injury that progress over several hours. Spinal cord reflex arcs immediately above the level of injury also may be depressed severely on the basis of the Schiff-Sherrington phenomenon. The end of the spinal shock phase of spinal cord injury is signaled by the return of elicitable abnormal cutaneospinal or muscle spindle reflex arcs. Autonomic reflex arcs involving relay to secondary ganglionic neurons outside the spinal cord may be affected variably during spinal shock, and their return after spinal shock abates is variable. The returning spinal cord reflex arcs below the level of injury are irrevocably altered and are the substrate on which rehabilitation efforts are based.

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. Buchler U, Frey HP: Retrograde posterior interosseous flap. J Hand Surg Am 1991;16:283-292.

This is a typical presentation of the patellar clunk syndrome. The syndrome usually follows implantation of a posterior stabilized prosthesis. It is thought to be the result of femoral component design and altered extensor mechanics. The condition usually resolves with arthroscopic debridement of the suprapatellar fibrous nodule. Arthrotomy or revision is seldom warranted. Beight JL, Yao B, Hozack WJ, Hearn SL, Booth RE Jr: The patellar "clunk" syndrome after posterior stabilized total knee arthroplasty. Clin Orthop 1994;299:139-142.

The patient has frostbite involving both feet. Rapid rewarming in a protected environment is the initial treatment. A footbath with water at 104.0 degrees F to 107.6 degrees F (40 degrees C to 42 degrees C) is ideal. This facilitates a uniform rewarming of the involved tissue. The other choices are less than ideal. Appliances such as heating pads provide uneven heating and may actually burn the skin. Pinzur MS: Frostbite: Prevention and treatment. Biomechanics 1997;4:14-21.

The long thoracic nerve, which innervates the serratus anterior, is prone to injury because of its superficial location along the chest wall. The long thoracic nerve is derived from the roots of C5, C6, and C7. The spinal accessory nerve innervates the trapezius, and the thoracodorsal nerve innervates the latissimus dorsi. The posterior cord of the brachial plexus provides the axillary and the radial nerves. Hollinshead WH: Anatomy for Surgeons: The Back and Limbs, ed 3. Philadelphia, PA, Harper and Row, 1982, pp 259-340.

Kayanja and associates, in a number of biomechanical studies, showed that in a kyphotic spine the strain is located at the apex of the deformity, the force is transmitted to the superior adjacent vertebrae, and that realignment and cement augmentation effectively normalize the load transfer. Kayanja MM, Ferrara LA, Lieberman IH: Distribution of anterior cortical shear strain after a thoracic wedge compression fracture. Spine J 2004;4:76-87. Kayanja MM, Togawa D, Lieberman IH: Biomechanical changes after the augmentation of experimental osteoporotic vertebral compression fractures in the cadaveric thoracic spine. Spine J 2005;5:55-63. Kayanja MM, Schlenk R, Togawa D, et al: The biomechanics of 1, 2, and 3 levels of vertebral augmentation with polymethylmethacrylate in multilevel spinal segments. Spine 2006;31:769-774.

Functional improvement after revision rotator cuff surgery is most likely to occur in patients with an intact deltoid, good-quality rotator cuff tissue, preoperative active elevation alone to 90 degrees, and only one prior rotator cuff repair. In this patient, the compromised deltoid origin might make functional improvement less likely. Djurasovic M, Marra G, Arroyo JS, et al: Revision rotator cuff repair: Factors influencing results. J Bone Joint Surg Am 2001;83:1849-1855. Bigliani LU, Cordasco FA, McIlveen SJ, et al: Operative treatment of failed repairs of the rotator cuff. J Bone Joint Surg Am 1992;74:1505-1515.

The MRI scan shows near complete involvement of the femoral head with bone marrow changes and some collapse of the necrotic segment. This is most suggestive of osteonecrosis.

The patient has had a clear and sudden onset of a profound neurologic deficit. The radiographic studies suggest a lesion in the conus medullaris that appears to be intradural and intramedullary. MRI, with and without contrast, will best evaluate this mass further. The addition of gadolinium allows further evaluation of vascularity and the extent of the lesion. Eichler ME, Dacey RG: Intramedullary spinal cord tumors, in Bridwell KH, Dewald RL (eds): The Textbook of Spine Surgery, ed 2. Philadelphia, PA, Lippincott-Raven, 1997, vol 2, pp 2089-2116.

Acetabular component loosening has been reported as the most common mode of failure following total hip arthroplasty in patients with a previous acetabular fracture. Following acetabular fracture and subsequent open reduction and internal fixation, the bone quality and vascularity are compromised, thus reducing the success rate of acetabular component cementless fixation. Jimenez ML, Tile M, Schenk RS: Total hip replacement after acetabular fracture. Orthop Clin 1997;28:435-446.

The MRI scan shows detachment of the subscapularis from its insertion on the lesser tuberosity. The examination finding is consistent with a positive lift-off test, also indicating a tear of the subscapularis. Lyons RP, Green A: Subscapularis tendon tears. J Am Acad Orthop Surg 2005;13:353-363.

The perichondrial fibrous ring of La Croix acts as a limiting membrane that provides mechanical support for the bone-cartilage junction of the growth plate. It is continuous with the ossification groove of Ranvier, which contributes chondrocytes for the increase in width of the growth plate. The zone of provisional calcification lies at the bottom of the hypertrophic zone and is the site of initial calcification of the matrix. It is quite weak and usually is the cleavage plane for fractures; therefore, it does not qualify as mechanical support. The last intact transverse septum separates the zone of provisional calcification from the primary spongiosa and provides no real support to the physis. The primary spongiosa is the part of the metaphysis nearest the physis. Netter FH: Growth plate, in Woodburne RT, Crelin ES, Kaplan FS, Dingle RV (eds): The Ciba Collection of Medical Illustrations. Summit, NJ, Ciba-Geigy Corporation, 1987, vol 8, pp 166-167.

The mechanism and environment in which the injury occurred, the clinical picture, and the radiographic findings of gas in the tissues suggest an anaerobic Gram-positive bacterial infection. This can be a life- and limb-threatening infection. Treatment should consist of wide debridement of all devitalized tissue, and intravenous antibiotics should be started. Wounds should be left open to allow bacterial effluent and increase oxygen tension in the wound. Hyperbaric oxygen may be used as an adjuvant but is no substitute for debridement. Pellegrini VD, Reid JS, Evarts CM: Complications, in Rockwood CA, Green DP, Bucholz RW, et al (eds): Rockwood and Green's Fractures in Adults, ed 4. Philadelphia, PA, Lippincott-Raven, 1996, vol 1, pp 458-463.

The patient has a pars interarticularis defect of L5 without apparent listhesis. The other diagnoses are not present. Papanicolaou N, Wilkinson RH, Emmans JB, Treves S, Micheli LJ: Bone scintigraphy and radiography in young athletes with low back pain. Am J Roentgenol 1985;145:1039-1044.

The examination and radiographs reveal a closed fracture-dislocation of the ankle with tibiofibular diastasis. Immediate fixation of the medial malleolus and plating of the fibula are indicated. If residual tibiofibular diastasis occurs with lateral translation of the fibula after plating, a syndesmotic screw is placed to stabilize the syndesmosis. Ankle fracture-dislocations associated with a proximal fibular fracture (Maisonneuve fracture) require syndesmotic fixation, but the fibula is not plated. Unstable ankle fractures require surgical treatment. If swelling is severe (fracture blisters, loss of skin wrinkling), a compressive splint is applied and surgery is delayed for 5 to 7 days. Browner BD, Jupiter JB, Levine AM, Trafton PG: Skeletal Trauma. Philadelphia, PA, WB Saunders, 1992, pp 1887-1957.

After major limb replantation, the occurrence of ischemic rhabdomyonecrosis can result in lactic acidosis and myoglobulinemia. These complications can be limited by rapid repair of the arterial supply, potentially using a shunt before skeletal stability. Repair of the venous system should be performed after repair of the artery. High volume fluid replacement will maintain a diuresis, thus limiting the complications from myoglobulinemia. Wood MB: Replantations about the elbow, in Morrey BF (ed): The Elbow and Its Disorders. Philadelphia, PA, WB Saunders, 1985, pp 472-480.

The patient has no clinical or observed signs of sepsis. The skin just proximal to the gangrenous tissue appears somewhat hyperemic and is clearly viable. These wounds should be managed much like burn wounds. Moist dressings should be used until the tissue clearly demarcates. Much of the insult may simply be superficial and only require late debridement. McAdams TR, Swenson DR, Miller RA: Frostbite: An orthopedic perspective. Am J Orthop 1999;28:21-26.

The main function of collagen in articular cartilage is to provide the tissue's tensile strength. It also immobilizes proteoglycans within the extracellular matrix. Compressive properties are maintained by proteoglycans. Cartilage metabolism is maintained by the indwelling chondrocytes. The flow of water through the tissue promotes transport of nutrients and provides a source of lubricant for the joint. Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 3-44.

The meniscal cartilage, like articular cartilage, possesses viscoelastic properties. The extracellular matrix is a biphasic structure composed of a solid phase (collagen, proteoglycan) that acts as a fiber-reinforced porous-permeable composite, and a fluid phase that may be forced through the solid matrix by a hydraulic pressure gradient. Although these properties are shared with articular cartilage, the meniscus is more elastic and less permeable than articular cartilage. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 3-23.

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

The patient has primary scapular-trapezius winging. This condition can be caused by blunt trauma to the relatively superficial spinal accessory nerve that is located in the floor of the posterior cervical triangle in the subcutaneous tissue. Other causes of injury include penetrating trauma, traction, or surgical injury. With trapezius winging, the shoulder appears depressed and laterally translated because of an unopposed serratus anterior. This contrasts with primary serratus anterior winging, which is caused by injury to the long thoracic nerve. In this condition, the scapula assumes a position of superior elevation and medial translation, and the inferior angle is rotated medially. The thoracodorsal nerve supplies the latissimus dorsi and is not involved in primary scapular winging. Kuhn JE, Plancher KD, Hawkins RJ: Scapular winging. J Am Acad Orthop Surg 1995;3:319-325.

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

The plain radiographs reveal a pedunculated osteochondroma with a fracture. There is a bony growth in the metaphysis of a long bone, on a stalk that is directed away from the nearby epiphysis. On the AP view, the host cortical and medullary bone are shown as "blending" with lesional bone. There is also a fracture through the lesion. Based on these radiographic findings, the diagnosis is an osteochondroma; therefore, initial management of an acute fracture of an osteochondroma is symptomatic treatment alone. Additional imaging studies are not indicated in this patient. At times it may be difficult to distinguish a sessile osteochondroma from a parosteal osteosarcoma. In the latter case, the host medullary bone and lesion bone are not confluent. A CT scan may be helpful to distinguish if the host medullary and cortical bone are confluent with the lesion.

Soft-tissue sarcomas are the sixth most common cancer in children. Rhabdomyosarcoma is the most common type of pediatric soft-tissue sarcoma. Nearly 50% of rhabdomyosarcomas are diagnosed in children who are age 5 years or younger. Unfortunately, there has not been a significant increase in survival in children with metastatic rhabdomyosarcoma despite aggressive therapy including multiple-drug chemotherapy regimens.

Lumbar spinal stenosis with lumbar radiculopathy can be commonly caused by a synovial cyst arising from the facet joints. Lyons and associates reported on the surgical treatment of synovial cysts in 194 patients. Of the 147 with follow-up data, 91% reported good pain relief and 82% had improvement of their motor deficits. Epstein reported a 58% to 63% incidence of good/excellent results and a 38 to 42 point improvement on the SF-36 Physical Function Scale. It was also suggested that since the presence of a synovial cyst indicates facet pathology, possible fusion should be considered in these patients, especially those with underlying spondylolisthesis. Lyons MK, Atkinson JL, Wharen RE, et al: Surgical evaluation and management of lumbar synovial cysts: The Mayo Clinic Experience. J Neurosurg 2000;93:53-57. Khan AM, Synnot K, Cammisa FP, et al: Lumbar synovial cysts of the spine: An evaluation of surgical outcome. J Spinal Disord Tech 2005;18:127-131.

The patient has several indications that he is not ready for definitive fixation of the femoral shaft fracture at this point. He is cold with a core temperature of 93 degrees F, and hypothermia of less than 95 degrees F (35 degrees C) has been shown to be associated with an increased mortality rate in trauma patients. The patient has also not been resuscitated based on his increasing lactate levels and although controversial, it has been shown that temporary external fixation leads to a lower incidence of multiple organ failure and acute respiratory distress syndrome. Shafi S, Elliot AC, Gentilello L: Is hypothermia simply a marker of shock and injury severity or an independent risk factor for mortality in trauma patients? Analysis of a large national trauma registry. J Trauma 2005;59:1081-1085. Pape HC, Hildebrand F, Pertschy S, et al: Changes in the management of femoral shaft fractures in polytrauma patients: From early total care to damage control orthopedic surgery. J Trauma 2002;53:452-461.

Neer and associates focused on mechanical and nutritional factors as the etiology of rotator cuff arthropathy. McCarty and associates, in describing a similar syndrome known as Milwaukee shoulder, focused on an inflammatory cause in proposing the pathogenic role of hydroxyapatite, a basic calcium phosphate. Neer CS II, Craig EV, Fukuda H: Cuff-tear arthropathy. J Bone Joint Surg Am 1983;65:1232-1244.

Humeral arthroplasty is indicated for chronic posterior dislocations when the impression defect in the humeral head is greater than 45% to 50%. If the condition remains undiagnosed for more than 9 to 12 months, secondary degenerative changes on the glenoid may occur, necessitating total shoulder arthroplasty. Open reduction and transfer of the subscapularis and lesser tuberosity are used for impression defects that consist of 20% to 40% of the humeral articular surface. Closed reduction and immobilization with the arm in slight extension and external rotation is useful when the posterior dislocation is diagnosed within the first 6 weeks and the articular defect is less than 20%. Hawkins RJ, Neer CS II, Pianta RM, Mendoza FX: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.

Elbow dislocations in children are rare injuries and usually result from a fall on an outstretched arm. The incidence of these injuries increases as patients age and concurrently the incidence of supracondylar humerus fractures decreases. In adolescent patients, simple elbow dislocations are treated with splint immobilization and the initiation of physical therapy once comfortable. The practitioner must be aware of structures that may get caught in the joint on reduction. These include the median nerve as well as the medial epicondyle. In this patient, the radiographs reveal a medial epicondyle fracture. Postreduction radiographs show the joint to be incongruous secondary to intra-articular displacement. At this point, the most appropriate treatment is to perform an open reduction and repair of the medial epicondyle fragment. Rasool MN: Dislocations of the elbow in children. J Bone Joint Surg Br 2004;86:1050-1058.

The images reveal a large mass in the posterior thigh arising from the sciatic nerve. The lesion is edematous, and the gadolinium image reveals rim enhancement, suggesting necrosis, given that the STIR image is not uniformly bright as would be seen in a cystic lesion. The PET scan has increased uptake, in this case a standard unit value (SUV) of greater than 2.0. These findings are all very suggestive of a malignant process. The history of neurofibromatosis makes a malignant peripheral nerve sheath tumor, or neurofibrosarcoma, the most likely diagnosis. The term "peripheral nerve sheath tumor" has replaced neurolemmoma and schwannoma. Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 225-230.

Following a radial nerve neurapraxia above the elbow, muscle recovery can be expected in a predictable pattern. Although variations will occur, the return of function or reinnervation usually occurs in the following order: brachioradialis, extensor carpi radialis longus, supinator, extensor carpi radialis brevis, extensor carpi ulnaris, extensor digitorum comminus, extensor digiti minimi, extensor indicis proprious, extensor pollicis longus, abductor pollicis longus, and extensor pollicis brevis. Netter F: The Ciba Collection of Medical Illustrations: The Musculoskeletal System. Part 1, Anatomy, Physiology and Metabolic Disorders. West Caldwell, NJ, Ciba-Geigy, 1991, vol 8, p 53.

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

The standard practice in the pharmacologic treatment of a spinal cord injury in the United States has been the administration of methylprednisolone with an initial bolus of 30 mg/kg followed by 5.4 mg/kg for 24 hours, in accordance with the findings of the second and third National Acute Spinal Cord Injury Studies (NASCIS). Although the studies have subsequently drawn criticism for their methodology and outcomes, it has been generally accepted that beneficial neurologic outcomes were anticipated in patients who were able to start the protocol within 8 hours of their initial injury. Further improvement was noted in patients receiving the methylprednisolone within 3 hours of their injury and continuing an infusion for 48 hours. In this patient, who is outside the 8-hour treatment window, no studies have supported starting the methylprednisolone protocol at this time. Braken MB, Shepard MJ, Holford TR, et al: Administration of methylprednisolone for 24 or 48 hours or tirilazad mesylate for 48 hours in the treatment of acute spinal cord injury: Results of the third National Acute Spinal Cord Injury Randomized Controlled Trial. National Acute Spinal Cord Injury Study. JAMA 1997;277:1597-1604.

Open reduction and internal fixation is the treatment of choice for accurate reduction of the disrupted intercarpal ligaments. In addition, the displaced scaphoid fracture will require open reduction and internal fixation and possible bone grafting. Closed reduction and long arm casting will not allow accurate reduction of the dislocated intracarpal intervals, and it is unlikely to allow accurate reduction of the scaphoid. The maneuver required to effect closed reduction of a displaced scaphoid fracture will most likely cause the scaphoid lunate interval to displace. Closed reduction with percutaneous pin fixation or with an external fixator is unable to effect anatomic reduction of the injury. Proximal row carpectomy is used as a salvage procedure for a variety of degenerative and posttraumatic problems of the wrist. Kozin SH: Perilunate injuries: Diagnosis and treatment. J Am Acad Orthop Surg 1998;6:114-120. Herzberg G, Comtet JJ, Linscheid RL, Amadio PC, Cooney WP, Stalder J: Perilunate dislocations and fracture-dislocations: A multicenter study. J Hand Surg Am 1993;18:768-779.

In general, a previously healthy patient with an acute onset of nontraumatic lower back pain does not need diagnostic imaging before proceeding with therapeutic treatment. In the absence of any "red flags" during the history and physical examination, such as trauma or constitutional symptoms (ie, fevers, chills, weight loss), the appropriate treatment for acute onset lower back pain is purely symptomatic treatment including limited analgesics and early range of motion. Diagnostic imaging is not necessary unless the initial treatment is unsuccessful and symptoms are prolonged. Miller and associates suggested that the use of radiographs can lead to better patient satisfaction but not necessarily better outcomes. Miller P, Kendrick D, Bentley E, et al: Cost effectiveness of lumbar spine radiographs in primary care patients with low back pain. Spine 2002;27:2291-2297.

Avulsion fractures of the tibial spine are rare injuries that result from rapid deceleration or hyperextension of the knee in skeletally immature individuals. This injury is the equivalent of ruptures of the anterior cruciate ligament in adults. These fractures are classified as types 1 through 3. Type 1 is a minimally displaced fracture, type 2 fractures have an intact posterior hinge, and type 3 fractures have complete separation. The radiograph demonstrates a completely displaced, or type III, tibial spine avulsion. Surgical reduction is indicated in type 2 fractures that fail to reduce with knee extension and in all type 3 fractures. Reduction may be arthroscopic or open, with fixation of the bony fragment using a method that maintains physeal integrity and prevents later growth arrest. Preferred techniques would be with suture or an intra-epiphyseal screw Wiley JJ, Baxter MP: Tibial spine fractures in children. Clin Orthop 1990;255:54-60. Mulhall KJ, Dowdall J, Grannell M, et al: Tibial spine fractures: An analysis of outcome in surgically treated type III injuries. Injury 1999;30:289-292. Owens BD, Crane GK, Plante T, et al: Treatment of type III tibial intercondylar eminence fractures in skeletally immature athletes. Am J Orthop 2003;32:103-105.

The patient has an acute fracture of the proximal pole. A 100% healing rate has been reported for open reduction and internal fixation of proximal pole fractures via a dorsal approach. This allows for direct viewing of the fracture line, facilitates reduction, and bone grafting can be done through the same incision if necessary. A vascularized or corticocancellous graft is reserved for nonunions. Proximal fractures are very slow to heal with a cast, if they heal at all. As a small fragment, percutaneous fixation is very difficult and has been reported for waist fractures. Rettig ME, Raskin KB: Retrograde compression screw fixation of acute proximal pole scaphoid fractures. J Hand Surg Am 1999;24:1206-1210.

Surgery is not indicated in a patient who has a mild deformity and no pain. Shoe wear modifications should be recommended.

The patient has pain involving the cervical and lumbar spine as well as pain and swelling in both the knees and ankles. As such, this can be classified as polyarticular arthritis. The presence of multiple joint symptoms in the lower extremities, the absence of a history of trauma, and the multiple joints involved direct attention away from the spine as the etiology of this patient's pain. Radiographs of the involved joints are not likely to yield much useful information to assist with a diagnosis. Likewise, an MRI scan of the lumbar spine is not likely to provide much information regarding the etiology of the patient's condition. When a rheumatologic illness is suspected, the selective use of confirmatory laboratory testing can aid in arriving at a correct diagnosis. A presumed case of gout or chondrocalcinosis can be confirmed by the presence of the appropriate crystals in a joint-fluid aspiration. Because of the patient's recent trip to Costa Rica and the subsequent gastroenteritis, a CBC count, ESR, and CRP should be ordered to rule out infectious and inflammatory versus noninflammatory conditions. Rheumatoid factor (RF) in general should only be ordered for patients with polyarticular joint inflammation for more than 6 weeks. The presence of rheumatoid factor does not indicate rheumatoid arthritis. Antinuclear antibodies (ANA) should be ordered when a connective tissue disease such as systemic lupus erythematosus (SLE) is suspected on the basis of specific history and physical examination findings, such as inflammatory arthritis. Human leukocyte antigen-B27 (HLA-B27) should be ordered only when the patient's history is compatible with ankylosing spondylitis or Reiter's syndrome and this patient had a history of Reiter's syndrome. Gardner GC, Kadel NJ: Ordering and interpreting rheumatologic laboratory tests. J Am Acad Orthop Surg 2003;11:60-67.

The superior glenohumeral ligament (SGHL) and coracohumeral ligament serve as primary static restraints against inferior translation of the arm when the shoulder is in 0 degrees of abduction. Of these, the coracohumeral ligament has been shown to have a greater cross-sectional area, greater stiffness, and greater ultimate load than the SGHL. The inferior glenohumeral ligament plays a greater stabilizing role with increasing abduction of the arm. The coracoacromial ligament may help provide superior stability, especially when the rotator cuff is deficient. The coracoclavicular ligaments stabilize the acromioclavicular joint. Boardman ND, Debski RE, Warner JJ, et al: Tensile properties of the superior glenohumeral and coracohumeral ligaments. J Shoulder Elbow Surg 1996;5:249-254.

The privacy rules do not require an individual's written authorization for certain permitted or required uses and disclosures of the medical records. Patient or parental authorization is not required for disclosures for certain purposes related to treatment, payment, or health care operations. Specifically, HIPAA does not require a covered entity to obtain patient authorization for many of the health care industry's most fundamental activities such as providing care. Carroll R: Risk Management Handbook for Health Care Organizations, ed 4. Hoboken, NJ, Jossey-Bass, 2003, p 1142.

Given the size of the rotator cuff tear, it is likely to be repaired; therefore, the treatment of choice is a total shoulder replacement with rotator cuff repair. Severe rotator cuff insufficiency can lead to early glenoid failure because of superior instability, and glenoid resurfacing should be avoided in those instances. Boyd AD Jr, Thomas WH, Scott RD, Sledge CB, Thornhill TS: Total shoulder arthroplasty versus hemiarthroplasty: Indications for glenoid resurfacing. J Arthroplasty 1990;5:329-336.

The radiograph shows enlargement of the bone, coarse trabeculation, a blastic appearance, and thickening of the cortex, revealing the classic appearance of Paget's disease in the sclerotic phase, the most common presentation. While lymphoma may present as a blastic lesion, it will not have the same enlargement, coarse trabeculation of bone, and the significant sclerosis seen here. Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 211-215.

The MRI scans reveal a postoperative infection. Observation and antibiotics are not appropriate choices. There is a large fluid collection and this requires decompression because the patient has neurologic changes. There is considerable debate regarding the removal of hardware. Many contend that biofilm on the implants can harbor the infection. However, these complications usually can be treated with serial irrigations, debridements, and IV antibiotics. The incidence of infection has been widely studied with varying rates in fusions with instrumentation. Rates appear to be increased with instrumentation, yet these infections usually can be managed without hardware removal. Glassman SD, Dimar JR, Puno RM, et al: Salvage of instrumental lumbar fusions complicated by surgical wound infection. Spine 1996;21:2163-2169.

There is no difference between the rates of union, malunion, range of motion of the hip or knee, muscle weakness, or infection for the two types of femoral nail insertion. The only difference is the location of the morbidity, which is around the insertion point of the rod. The antegrade technique has more morbidity about the hip, and the retrograde insertion technique has more morbidity about the knee. Morgan E, Ostrum RF, DiCicco J, McElroy J, Poka A: Effects of retrograde femoral intramedullary nailing on the patellofemoral articulation. J Orthop Trauma 1999;13:13-16. Ricci WM, Bellabarba C, Evanoff B, Herscovici D, DiPasquale T, Sanders R: Retrograde versus antegrade nailing of femoral shaft fractures. J Orthop Trauma 2001;15:161-169. Ostrum RF, Agarwal A, Lakatos R, Poka A: Prospective comparison of retrograde and antegrade femoral intramedullary nailing. J Orthop Trauma 2000;14:496-501.

The CT scan reveals a hook of the hamate nonunion with irregular resorption at the fracture site, which is at the base of the hamate. Symptomatic relief of the pain and discomfort has been well documented after excision of the hook of the hamate. Ultrasound therapy will not provide long-term symptomatic relief or induce nonunion healing. MRI for further soft-tissue evaluation is inappropriate because this is a bony problem; the bony architecture of the wrist is best visualized by CT. Open reduction and internal fixation of the hook of the hamate does not provide the symptomatic relief that is found with excision of the hook of the hamate. In addition, the technical difficulties and relative risk of persistent nonunion after open reduction and internal fixation are not merited when hamate excision can be effected easily and causes no long-term untoward effects. Electrodiagnostic evaluation is inappropriate because there is no history of the persistent numbness and tingling that is found in peripheral compression neuropathies. Stark HH, Chao EK, Zemel NP, Rickard TA, Ashworth CR: Fracture of the hook of the hamate. J Bone Joint Surg Am 1989;71:1206-1207. Failla JM: Hook of hamate vascularity: Vulnerability to osteonecrosis and nonunion. J Hand Surg Am 1993;18:1075-1079. Carter PR, Easton RG, Littler JW: Ununited fracture of the hook of the hamate. J Bone Joint Surg Am 1977;59:583-588.

Although fractures of the proximal tibial metaphysis in young children appear innocuous, development of a progressive valgus deformity is possible despite adequate and appropriate treatment. When treating a child with this injury, it is prudent to warn the parents that a valgus deformity of the tibia may develop. The most likely cause is asymmetric growth of the proximal tibial physis. Because spontaneous angular improvement can be expected in most patients, surgery to correct these deformities should be delayed at least 2 to 3 years and should be limited to patients who have symptoms. There are no studies that document the efficacy of bracing for this deformity. Tuten HR, Keeler KA, Gabos PG, et al: Posttraumatic tibia valga in children: A long-term follow-up note. J Bone Joint Surg Am 1999;81:799-810.

If the neck is immobilized in excessive extension, it can be difficult for the patient to swallow. If the patient had injured the recurrent or superior laryngeal nerve at the time of the accident, it is likely to have manifested itself earlier on. Esophageal trauma or retropharyngeal edema or hematoma from the fracture also should have manifested itself earlier. Because the fracture was completely reduced, it is unlikely that moving the small fragment posteriorly would have injured the esophagus. Garfin SR, Botte MJ, Waters RL, Nickel VL: Complications in the use of halo fixation device. J Bone Joint Surg Am 1986;68:320-325.

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. 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.

Based on the findings, the treatment of choice is resection of the sternoclavicular joint. Antibiotic therapy, repeat aspirations, hyperbaric oxygen, and simple irrigation and debridement are generally ineffective and associated with a high rate of recurrence.

Most closed simple dislocations are best managed with early range of motion. Posterior dislocation typically occurs through a posterolateral rotatory mechanism. When placed in pronation, the elbow has greater stability when the medial ligamentous structures are intact. In traumatic dislocations, MRI rarely provides additional information that will affect treatment. In elbows that remain unstable, primary repair is preferred over ligament reconstruction. Cast immobilization increases the risk of arthrofibrosis.

The work-up for a patient with an unknown primary lesion that is metastatic to bone includes a search for the primary tumor and other sites of metastasis. This involves conducting a thorough history and physical examination, appropriate laboratory studies, bone scan, chest radiograph, and CT of the chest, abdomen, and pelvis. In women, a mammogram may be indicated. CT of the brain is not necessary in the early stages of a metastatic work-up. Simon MA, Bartucci EJ: The search for the primary tumor in patients with skeletal metastases of unknown origin. Cancer 1986;58:1088-1095.

Halo fixation is the most rigid form of cervical orthosis, but complications can arise from improper placement of the initial halo ring. A relatively safe zone for anterior pin placement is located 1 cm above the orbital rim and superior to the lateral two thirds of the orbit. This position avoids the supraorbital and supratrochlear nerves and arteries over the medial one third of the orbit. The more lateral positions in the temporal fossa have very thin bone and can interfere with the muscles of mastication. Posterior pin site locations are less critical; positioning on the posterolateral aspect of the skull, diagonal to the contralateral anterior pins, is generally desirable. Botte MJ, Byrne TP, Abrams RA, et al: Halo skeletal fixation: Techniques of application and prevention of complications. J Am Acad Orthop Surg 1996;4:44-53.

The patient has a slipped capital femoral epiphysis (SCFE) at a younger than average age (average age 13.5 years for boys and 12.0 years for girls); therefore, an etiology that is not idiopathic must be considered. Hypothyroidism can result in a SCFE, but these children typically fall into the category of less than the 10th percentile for height. SCFE may develop in children with a growth hormone deficiency who have undergone hormonal replacement. Osteodystrophy caused by chronic renal failure may result in a SCFE, but the bone quality is markedly osteopenic on radiographs and the children are chronically ill with both low height and weight percentiles. An elevated estrogen level results in physeal closure and is protective to physeal slippage. Therefore, this child will most likely have normal laboratory values. Loder RT, Hensinger RN: Slipped capital femoral epiphysis associated with renal failure osteodystrophy. J Pediatr Orthop 1997;17:205-211.