100 Orthopedic MCQs: Spine, Trauma, Joint Reconstruction & Sports Medicine | Comprehensive ABOS Exam

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. 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.

The MRI scan shows a rupture of the patellar tendon. This injury is most appropriately addressed with primary repair. For athletic individuals, the results of nonsurgical management are suboptimal. Reconstructive procedures are not necessary. Matava MJ: Patellar tendon ruptures. J Am Acad Orthop Surg 1996;4:287-296.

The patient has patellar tendinitis (jumper's knee). It is a common overuse condition seen in runners, volleyball players, soccer players, and jumpers but can be seen in any activity in which repeated extension of the knee is required. In the acute setting, the pain is well localized and there is tenderness and sometimes swelling of the tendon. MRI is recommended for evaluating chronic cases and for surgical planning. In the acute phases, ice, rest, and avoidance of the offending activity are recommended. Weakness of the quadriceps and hamstring muscle are thought to contribute to this problem; therefore, stretching and isometric exercise in a limited range of motion are important. Complete rest and intratendinous injections of steroids are detrimental to tendon physiology. Stanish WD, Rubinovich RM, Curwin S: Eccentric exercise in chronic tendinitis. Clin Orthop 1986;208:65-68.

The most common benign bone tumor in childhood is a nonossifying fibroma. It is estimated that 30% of children have a nonossifying fibroma. In most patients, the lesion is not identified until a radiograph is obtained for unrelated reasons. Similarly, most identified cases of fibrous cortical defect are not biopsied because the radiographic and clinical presentations are diagnostic. Aboulafia AJ, Kennon RE, Jelinek JS: Benign bone tumors of childhood. J Am Acad Orthop Surg 1999;7:377-388.

The clinical photograph and radiograph show gout, which is the result of urate deposition in the joint and soft tissues. Radiographs frequently reveal periarticular erosions. The crystals are intracellular and negatively birefringent under the polarized microscope. Treatment for acute flares include colchicines, indomethacin, and corticosteroids (including injections). Medications such as allopurinol help prevent recurrent flares. Tophi such as that seen in this patient are often confused with and associated with infection. Wortmann RL, Kelley WM: Crystal-induced inflammation: Gout and hyperuricemia, in Harris ED, Budd RC, Firestein GS, et al (eds): Kelley's Textbook of Rheumatology, ed 7. New York, NY, Elsevier Science, 2005, pp 1402-1429. Trumble TE (ed): Hand Surgery Update 3: Hand, Elbow, & Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp 433-457.

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

The rate of wound infections has dramatically decreased with the routine use of prophylactic antibiotics. Factors known to increase the risk of infection include instrumentation, prolonged surgical time, excessive blood loss, poor perioperative nutritional status, a history of surgery, and a history of infection. The use of allograft does not result in an increased rate of infection. Adequate treatment requires early diagnosis and intervention. Temperature elevation and persistent wound drainage are highly suspicious for infection. An erythrocyte sedimentation rate and a WBC are not useful in diagnosis unless serial examinations show rising levels. Patients should be taken to the operating room where the entire wound can be reopened, irrigated, and debrided. Bone graft can be washed and replaced. Hardware should not be removed. The wound should be closed over suction drains. IV antibiotics should be given for a period of at least 10 days, followed by 6 weeks orally. Leaving the wound open to granulate with dressing changes results in prolonged hospitalization, inadequate treatment of the infection, and a poor cosmetic result. Lonstein JE: Complications of treatment, in Bradford DS, Lonstein JE, Moe JH, et al (eds): Moe's Textbook of Scoliosis and Other Spinal Deformities, ed 2. Philadelphia, Pa, WB Saunders, 1987, p 476.

The radiographs show classic findings for Koehler's disease (osteochondrosis of the navicular). The patient's age and clinical history are typical for this self-limiting condition. Patients will improve with time, but the duration of symptoms is much shorter if the patient is placed in a cast. There is no role for surgery in this disease.

Several large clinical studies have shown that the most common problem after elastic nailing of a femoral shaft fracture is persistent pain and irritation at the nail insertion site. Unacceptable shortening and malunion are very rare in a 7-year-old patient. Rotational malalignment also is unusual. Osteonecrosis has been reported in solid antegrade nailing but not with elastic nailing of femoral shaft fractures in skeletally immature patients. Flynn JM, Luedtke LM, Ganley TJ, et al: Comparison of titanium elastic nails with traction and a spica cast to treat femoral fractures in children. J Bone Joint Surg Am 2004;86:770-777. Flynn JM, Hresko T, Reynolds RA, et al: Titanium elastic nails for pediatric femur fractures: A multicenter study of early results with analysis of complications. J Pediatr Orthop 2001;21:4-8.

The amount of deformation resulting in response to an applied load depends on the stress distribution that the load creates in the structure and the stress versus strain behavior of the material that makes up the structure. Axial and bending loads create stress distributions that involve normal stresses and normal strains. Although all five responses are indeed material properties, only one, elastic modulus, relates normal stresses to normal strains. In fact, axial and bending stiffness are directly proportional to modulus, so that a nail made from stainless steel will have nearly twice the stiffness of a nail made from titanium alloy (because their respective elastic moduli differ by about a factor of two). Hayes WC, Bouxsein ML: Analysis of muscle and joint loads, in Mow VC, Hayes WC (eds): Basic Orthopaedic Biomechanics, ed 2. New York, NY, Lippincott-Raven, 1997, pp 74-82. 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 159-165.

In a large series of mini-open rotator cuff repairs, an infection rate of at least 2% was found, with the majority of the infections caused by Propionibacterium acnes. To prevent this complication, the shoulder should be re-prepped before the mini-open incision is made to prevent bacterial contamination from the arthroscopic procedure. Herrera MF, Bauer G, Reynolds F, et al: Infection after mini-open rotator cuff repair. J Shoulder Elbow Surg 2002;11:605-608.

Women older than age 50 years should receive daily supplementation with calcium and vitamin D to help preserve bone density. Bone mineral density testing is recommended for women age 65 years or older and postmenopausal women with at least one risk factor for osteoporotic fractures: prior fragility fracture, low estrogen levels, premature menopause, long-term secondary amenorrhea, glucocorticoid therapy, maternal history of hip fracture, or low body mass index. Hormone therapy is not approved for the treatment of osteoporosis. Gass M, Dawson-Hughes B: Preventing osteoporosis-related fractures: An overview. Am J Med 2006;119:S3-S11.

Pacinian corpuscles are nerve endings that provide the perception of pressure.

Histologic grade, the presence or absence of metastatic disease, and tumor size are important prognostic factors. Of the available choices, however, the size of the sarcoma is the most important prognostic indicator. A tumor size of greater than 5 cm is a more important prognostic factor than tumor location. Patients with sarcomas that measure 5 cm or less have nearly identical 3-year survival rates regardless of whether the tumor is subcutaneous or deep. Histologic grade (high versus low) is an important factor. However, histologic subtype frequently is not as important a factor as tumor size.

Fractures that occur through the primary spongiosa at the subphyseal region of the metaphysis are highly specific for child abuse. On radiographic studies, the metaphyseal lucency in these injuries may appear as either the so-called "bucket-handle" or "metaphyseal corner" fracture. These fractures are not typical features of osteogenesis imperfecta or vitamin D-resistant rickets. The ingestion of lead may lead to thick, transverse bands of increased density at the distal metaphysis. Fractures in the subphyseal region of the metaphysis are not typically seen in children who have osteomyelitis. Kocher MS, Kasser JR: Orthopaedic aspects of child abuse. J Am Acad Orthop Surg 2000;8:10-20.

Intrafocal pinning allows the Kirschner wires to be placed through a site of comminution and then drilled through intact cortex. Generally Kapandji intrafocal pinning is done for dorsal comminuted extra-articular dorsal bending fractures, but it also may be used to elevate and buttress radial comminution. Simple intra-articular fractures can also be treated with pinning alone. Intrafocal pinning works best as a dorsal or radial buttress to prevent shortening. When there is volar comminution, the fracture is prone to shortening and supplemental external fixation or plating is recommended. Trumble TE, Wagner W, Hanel DP, et al: Intrafocal (Kapandji) pinning of distal radius fractures with and without external fixation. J Hand Surg Am 1998;23:381-394. Choi KY, Chan WS, Lam TP, et al: Percutaneous Kirschner-wire pinning for severely displaced distal radial fractures in children: A report of 157 cases. J Bone Joint Surg Br 1995;77:797-801.

To date, only the percent of necrosis after induction chemotherapy in high-grade osteosarcomas seems to be of prognostic value. The value in soft-tissue sarcoma and rhabdomyosarcoma is being evaluated but has not been substantiated. Chondrosarcomas and parosteal osteosarcomas are not treated with chemotherapy. Rosen G, Marcove RC, Caparros B, Nirenberg A, Kosloff C, Huvos AG: Primary osteogenic sarcoma: The rationale for pre-operative chemotherapy and delayed surgery. Cancer 1979,43:2163-2177. Davis AM, Bell RS, Goodwin PJ: Prognostic factors in osteosarcoma: A critical review. J Clin Oncol 1994;12:423-431.

The imaging studies show a permeative lesion of the left hemipelvis with a large soft-tissue mass. The photomicrograph demonstrates a small blue cell tumor with pseudorosettes. The most likely diagnosis is primitive neuroectodermal tumor (Ewing's sarcoma family of tumors). MIC-2 is a highly sensitive and specific marker for this family of tumors. Cytokeratin is an epithelial marker. Vimentin is a mesenchymal marker. Thus, Ewing's sarcomas are cytokeratin negative and vimentin positive. Before discovery of the MIC-2 antigen, PAS and reticulin stains were commonly used to help differentiate Ewing's sarcoma from lymphoma. In contrast to lymphoma, Ewing's sarcomas are typically PAS positive and reticulin negative. Halliday BE, Slagel DD, Elsheikh TE, et al: Diagnostic utility of MIC-2 immunocytochemical staining in the differential diagnosis of small blue cell tumors. Diagn Cytopathol 1998;19:410-416.

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.

In the design of tibial and femoral components, a compromise must be made between contact stresses and constraint. Increased conformity increases constraint, limits motion, and potentially increases stress on the knee-cement interface. By increasing conformity, the surface area over which force is applied is increased, resulting in decreased peak contact stresses and decreased component wear rates. 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 265-274.

Type I fractures are trochanteric fractures usually secondary to osteolysis. Type II fractures are located around the stem. Type III fractures are distal to the stem. If the fracture and prosthesis are stable, the fracture can be treated nonsurgically. If the fracture is unstable, the stability of the prosthesis should be assessed. If the prosthesis is unstable (type IIB), treatment should consist of revision to a long stem prosthesis that bypasses the fracture by two cortical diameters. If, as in this patient, the prosthesis is not loose (type IIA), open reduction and internal fixation is the appropriate option. Proximal femoral allograft is appropriate for type IIIC fractures in which the proximal bone is significantly compromised and the femoral component is loose. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 455-492.

The history, physical examination, and radiographic findings are consistent with type IV sacral agenesis or caudal regression syndrome. These children are born with no lumbar spine or sacrum. The T12 vertebra is often prominent posteriorly. Popliteal webbing and knee flexion contractures are common with this diagnosis. There is a higher incidence of this diagnosis when the mother has diabetes mellitus. Maternal drug abuse and alcoholism can produce phenotypically unique children but without the findings described here. Maternal idiopathic scoliosis is not associated with caudal regression syndrome. Chan BW, Chan KS, Koide T, et al: Maternal diabetes increases the risk of caudal regression caused by retinoic acid. Diabetes 2002;51:2811-2816.

All of the options, except cementing the metaphyseal portion and press fitting the keel of the tibial component, have been shown to create strong and long-lasting constructs; however, cementing of both the platform and the keel offers the most predictable solution. Cementing the platform and not the keel has been shown to have a higher loosening rate than the more traditional methods of fully cementing or using screws to augment fixation.

The radiograph shows medial migration of the cementless acetabular component, strongly suggesting acetabular discontinuity with a combined segmental and cavitary medial deficiency. The treatment of choice is a morcellized or structural graft, supported with a reconstructive cage bridging the pelvic discontinuity, and a cemented cup. Whiteside LA: Selection of acetabular component, in Steinberg ME, Garino JP (eds): Revision Total Hip Arthroplasty. Philadelphia, PA, Lippincott Williams and Wilkins, 1999, pp 209-220.

The arterial supply to the hand is abundant and normally duplicated. The deep palmar arch as shown in this arteriogram typically receives its primary contribution from the radial artery which travels deep to the first dorsal compartment tendons and then returns to the volar aspect of the palm through the first web space. The superficial palmar arch receives its supply from the ulnar artery and is not visualized in this patient.

Nearly all approaches to shoulder arthroplasty require detachment of the subscapularis tendon from the humerus and subsequent repair. Healing of this tenotomy is one of the limiting factors in postoperative recovery. Failure of the tenotomy repair must be recognized and treated early with repeat repair or pectoralis muscle transfer for optimal results. Failure of the subscapularis is diagnosed clinically as excessive external rotation and weakness, especially in the lift-off or belly press position. Muscle testing can be difficult in the postoperative period and may not be possible to assess in those positions. Although MRI might be useful to confirm the diagnosis, studies may be limited by artifact. CT or electromyography would not be diagnostic. Wirth MA, Rockwood CA Jr: Complications of total shoulder-replacement arthroplasty. J Bone Joint Surg Am 1996;78:603-616.

Stress-strain plots allow easy comparison of a number of important mechanical properties, including elastic modulus (the slope of the initial straight line portion of the curve) and yield stress (the stress at the break in the curves for bone, steel, and titanium alloy). Important considerations here are much lower modulus and ultimate stress of bone and cement compared to the two metallic alloys, the fact that titanium is lower modulus but higher strength than stainless steel, and the identification of cement as the only brittle material among the four. Burstein AH, Wright TM: Fundamentals of Orthopaedic Biomechanics. Baltimore, MD, Williams and Wilkins, 1994, pp 97-129.

A Trendelenburg gait results from weakness of the gluteus medius, which is innervated by the L5 nerve root. A paracentral disk herniation at L4-L5 most commonly results in an L5 radiculopathy and thus weakness of the gluteus medius. A paracentral herniation at L5-S1 most commonly affects the S1 nerve root. A paracentral herniation at L3-L4, a central herniation at L3-L4, and a far lateral herniation at L4-L5 all affect the L4 root. Fardon DF, Garfin SR, Abitbol J, et al (eds): Orthopedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 323-332.

Conventional osteosarcoma most frequently occurs in the second decade, followed by the third decade. Approximately 70% to 75% of patients with osteosarcoma are between the ages of 10 and 25 years. Secondary osteosarcoma (arising in Paget's disease or radiation-induced) is seen in older adults. Simon MA, Springfield DS, et al: Osteogenic Sarcoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 266. Mirra JM: Bone Tumors: Clinical, Radiologic, and Pathologic Correlations. Philadelphia, PA, Lea and Febiger, 1989.

According to the classification of Levine and Edwards, a type I Hangman's fracture is minimally displaced without angulation and represents a stable injury. Good clinical success has been achieved with nonsurgical management consisting of use of a rigid collar until the patient reports pain relief, followed by quick mobilization.

Spinal cord injury in skeletally immature patients almost always leads to the development of paralytic spinal deformity. The age at injury is the most important factor affecting the development of scoliosis. Spinal cord injury that occurs more than 1 year prior to skeletal maturity is almost always followed by the development of scoliosis. In one study, scoliosis developed in 100% of children who were younger than age 10 years at the time of spinal cord injury. Scoliosis can occur after injury at any level. Spasticity is often a contributing factor. Up to two thirds of patients who have paralytic scoliosis prior to skeletal maturity will eventually require surgery for curve control. Mayfield JK, Erkkila JC, Winter RB: Spine deformity subsequent to acquired childhood spinal cord injury. J Bone Joint Surg Am 1981;63:1401-1411. Lancourt JE, Dickson JH, Carter RE: Paralytic spinal deformity following traumatic spinal cord injury in children and adolescents. J Bone Joint Surg Am 1981;63:47-53.

These are classic findings of osteonecrosis of the hip. The radiograph reveals the subchondral sclerotic pattern commonly seen in osteonecrosis and is quite extensive in this patient. The MRI scan reveals the typical serpentine-like region of low signal intensity with a central zone where the signal is similar to fat. Resnick D (ed): Diagnosis of Bone and Joint Disorders. Philadelphia, PA, WB Saunders, 2002, pp 3160-3162.

This rare complication occurs after fracture-dislocation and has been seen after surgical stabilization in the adolescent. In most reported cases, prolonged observation has been shown to result in revascularization. Pateder DB, Park HB, Chronopoulos E, et al: Humeral head osteonecrosis after anterior shoulder stabilization in an adolescent: A case report. J Bone Joint Surg Am 2004;86:2290-2293.

An inability to participate in athletics generally is considered an indication for continued symptomatic treatment only. All of the other answers suggest the possibility of more significant pathology that may require more urgent treatment. Frymoyer JW: Back pain and sciatica. N Engl J Med 1988;318:291-300.

In the thrower's elbow, ulnar neuritis is felt to result from both chronic compression and traction on the nerve that occurs during the throwing motion. Occasionally, subluxation of the nerve also can lead to symptoms. If nonsurgical management fails to provide relief, transposition of the nerve to an anterior subcutaneous location is the surgical procedure of choice. The nerve is held in its new position by one or two fascial slings created from the fascia of the common flexor origin. Schickendantz MS: Diagnosis and treatment of elbow disorders in the overhead athlete. Hand Clin 2002;18:65-75.

Achieving stability in chronic locked posterior dislocations of the shoulder remains a difficult challenge. Intraoperative measures include decreased humeral retroversion, anterior releases, and posterior capsular tightening. Postoperative rehabilitation is of equal importance. Immobilization in an external rotation brace (10 degrees to 15 degrees) with the arm at the side for 4 to 6 weeks is recommended to decrease tension in the posterior capsule. When passive range-of-motion exercises are instituted, they should be performed in the plane of the scapula to avoid stress posteriorly. Internal rotation and supine elevation should be avoided for similar reasons. Hawkins RJ, Neer CS II, Pianta RM, Mendoza FX: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.

Severely displaced acromioclavicular injuries disrupt the deltotrapezial fascia and muscular origin in addition to the ligaments (acromioclavicular and coracoclavicular or trapezoid and conoid). When the deltoid is still attached to the clavicle, an isometric shoulder shrug will tend to reduce the displacement. When the deltoid is detached but the trapezius is attached, this manuever will increase the deformity and surgery may be indicated.

Neurologic injury after shoulder replacement is relatively uncommon, occurring in 4% of shoulders in one large series. The importance of identifying and protecting the musculocutaneous and axillary nerves cannot be overemphasized; it is especially critical during revision arthroplasty when the normal anatomic relationships have been distorted. The long deltopectoral approach leaving the deltoid attached to the clavicle was found to be significant in the development of postoperative neurologic complications. A correlation was found between surgical time and postoperative neurologic complications, with long surgical times being associated with more neurologic complications. The presumed mechanism of injury is traction on the plexus that occurs during the surgery. A neurologic injury after total shoulder arthroplasty usually does not interfere with the long-term outcome of the arthroplasty itself; it is best managed by protective measures with passive range of motion of the involved extremity. Wirth MA, Rockwood CA Jr: Complications of shoulder arthroplasty. Clin Orthop 1994;307:47-69.

The radiographs show a bone-producing lesion in the distal femoral metaphysis in this case of classic osteosarcoma presenting in the most common location, the distal femur. The coronal MRI scan reveals a marrow-occupying lesion with extension into the soft tissues. The histology shows osteoid production by pleomorphic cells consistent with an osteosarcoma. Ewing's sarcoma is a bone tumor characterized by uniform small blue cells on histology. Rhabdomyosarcoma is the most common childhood soft-tissue sarcoma. Osteomyelitis has an inflammatory appearance on histology. Malignant fibrous histiocytoma of bone has a lytic radiographic appearance and a pleomorphic storiform pattern without osteoid on histology. Wold LE, Adler CP, Sim FH, et al: Atlas of Orthopedic Pathology, ed 2. Philadelphia, PA, WB Saunders, 2003, p 179.

The patient has a symptomatic painful atrophic midclavicular nonunion, and the treatment of choice is rigid internal fixation with a dynamic compression plate and autogenous bone grafting. A tension band effect is desired and achieved by placing the plate superiorly. Excellent success rates of 90% to 100% have been reported using this technique. Intramedullary screw fixation without bone grafting has a decreased success rate. Partial claviculectomy is not a preferred option. Jupiter JB, Leffert RD: Non-union of the clavicle: Associated complications and surgical management. J Bone Joint Surg Am 1987;69:753-760.

In a subgroup of patients with monoarticular JRA and a limb-length discrepancy that developed before the age of 9 years, Simon and associates showed that a subsequent growth deceleration on the affected side may correct a large part of the difference in length. This possibility would make surgery unnecessary and should prompt further observation. Simon S, Whiffen J, Shapiro F: Leg-length discrepancies in monoarticular and pauciarticular juvenile rheumatoid arthritis. J Bone Joint Surg Am 1981;63:209-215.

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

The patient has rhabdomyosarcoma. Axilliary node and bone marrow biopsy are part of the staging because about 12% of patients with rhabdomyosarcoma of the extremity have evidence of lymph nodes metastases at presentation. Bone marrow metastases have been shown to portend a worse prognosis. Lawrence W, Jr., Hays DM, Heyn R, Tefft M, Crist W, Beltangady M, et al: Lymphatic metastases with childhood rhabdomyosarcoma: A report from the Intergroup Rhabdomyosarcoma Study. Cancer 1987;60:910-915.

The long-term effect of transient quadriplegia is unknown. Based on a history of one brief episode of transient quadriplegia and normal examination and MRI findings, the risk of permanent spinal cord injury with a return to play is low. There is a risk of recurrent episodes of transient quadriplegia after the initial episode. Morganti C, Sweeney CA, Albanese SA, et al: Return to play after cervical spine injury. Spine 2001;26:1131-1136. Odor JM, Watkins RG, Dillin WH, et al: Incidence of cervical spinal stenosis in professional and rookie football players. Am J Sports Med 1990;18:507-509. Torg JS, Naranja RJ Jr, Palov H, et al: The relationship of developmental narrowing of the cervical spinal canal to reversible and irreversible injury of the cervical spinal cord in football players. J Bone Joint Surg Am 1996;78:1308-1314.

A large annular defect at the site of a lumbar disk herniation is associated with persistent radicular pain postoperatively. Large sequestered herniations and a positive SLR preoperatively correlate with good outcomes after diskectomy. Neither symptoms of more than 3 months' duration nor preoperative epidural steroid injections correlate with postoperative results after diskectomy. Carragee EJ, Han MY, Suen PW, et al: Clinical outcomes after lumbar discectomy for sciatica: The effects of fragment type and anular competence. J Bone Joint Surg Am 2003;85:102-108.

Much attention has been given to the use of supplemental postoperative analgesia with nonsteroidal anti-inflammatory drugs (NSAIDs), and a significant reduction in narcotic use has been recorded. However, a high failure rate of arthrodesis has been associated with the use of postoperative NSAIDs. Glassman and associates reported 29 cases of pseudarthrosis in 167 patients when ketorolac was used as a postoperative analgesic, whereas only five fusion failures were noted in 121 patients not using ketorolac. Indomethacin and ibuprofen have been shown to adversely affect bone formation in clinical and animal trials. Nicotine has also been shown in a number of studies to decrease the fusion rate. Oxycodone hydrochloride is a synthetic morphine and does not affect the fusion process. Glassman SD, Rose SM, Dimar JR, Puno RM, Campbell MJ, Johnson JR: The effect of postoperative nonsteroidal anti-inflammatory drug administration on spinal fusion. Spine 1998;23:834-838. Deguchi M, Rapoff AJ, Zdeblick TA: Posterolateral fusion for isthmic spondylolisthesis in adults: Analysis of fusion rate and clinical results. J Spinal Disord 1998;11:459-464.

Precoating of the femoral stem with PMMA results in increased bonding of the stem to the cement mantle. However, this has not been shown to result in superior survivorship compared with nonprecoated stems of similar design. In one series, the rate of revision of precoated stems was greater than that of nonprecoated cohorts. The wear and infection rates have not been shown to differ between precoated and nonprecoated stems. Sporer SM, Callaghan JJ, Olejniczak JP, Goetz DD, Johnston RC: The effects of surface roughness and polymethylmethacrylate precoating on the radiographic and clinical results of the Iowa hip prosthesis: A study of patients less than fifty years old. J Bone Joint Surg Am 1999;81:481-492.

Most patients who undergo transmetatarsal amputation do not require custom shoe wear or an orthosis above the ankle. A molded toe filler is used to prevent excessive shear that can lead to ulceration. Use of a soft toe filler without stiffening of the sole results in excessive flexibility from the shortened lever arm, which reduces the efficiency of gait. A firm footplate or carbon fiber base adds rigidity to aid in push-off. A rocker bottom also may be added to the shoe. Philbin TM, Leyes M, Sferra JJ, Donley BG: Orthotic and prosthetic devices in partial foot amputations. Foot Ankle Clin 2001;6:215-228.

Lateral subtalar dislocations, which are less common than medial subtalar dislocations, are high-energy injuries that are frequently associated with small osteochondral fractures. It is generally recommended that large fragments be internally fixed, and small fragments entrapped within the joint be excised. Although arthrosis frequently occurs after this injury and is the most common long-term complication, primary subtalar arthrodesis is not indicated. A talar neck fracture is not evident on the radiographs, and lateral subtalar dislocation usually does not lead to instability.

The images reveal a region of increased signal within the rectus femoris muscle with mild, ill-defined surrounding edema. The presence of high intensity signal on the T1-weighted image favors acute blood, in this case associated with a rectus femoris muscle tear or fatty tissue. However, because of fat suppression, a fatty lesion or lipoma would be dark on STIR, rather than bright as in this image. Most foreign bodies are low intensity signal and if small, are difficult to evaluate with MRI. The lack of adjacent subcutaneous soft-tissue edema or surrounding fluid makes pyomyositis an unlikely diagnosis.

The MRI scan reveals a subscapularis tear with a biceps that is out of the groove. Treatment in this patient is most predictable if the subscapularis is repaired. The biceps should either be tenodesed or tenotomized since it is unstable. Recentering of the biceps has been found to be unpredictable. Treatment of these lesions has been shown to have better results if the biceps is either released or tenodesed. This prevents recurrent biceps symptoms that can be source of surgical failure. Edwards TB, Walch G, Sirvenaux F, et al: Repair of tears of the subscapularis: Surgical technique. J Bone Joint Surg Am 2006;88:1-10. Deutsch A, Altcheck DW, Veltri DM, et al: Traumatic tears of the subscapularis tendon: Clinical diagnosis, magnetic resonance imaging findings, and operative treatment. Am J Sports Med 1997;25:13-22.

The radiograph shows a type V acromioclavicular separation with greater than 100% superior elevation of the clavicle. This finding implies detachment of the deltoid and trapezius from the distal clavicle. Because of severe compromise of function and potential compromise to the overlying skin, surgery is the treatment of choice for type V acromioclavicular separations. During reduction and repair, meticulous repair of the deltotrapezial fascia will also aid in securing the repair. Nuber GW, Bowen MK: Acromioclavicular joint injuries and distal clavicle fractures. J Am Acad Orthop Surg 1997;5:11-18.

Atraumatic subluxation or dislocation of the sternoclavicular joint typically occurs in individuals with generalized ligamentous laxity. It is generally not painful, has no long-term sequelae, and needs no treatment. In fact, it is more likely to be painful following surgery than if managed nonsurgically. Rockwood CA Jr, Odor JM: Spontaneous atraumatic anterior subluxation of the sternoclavicular joint. J Bone Joint Surg Am 1989;71:1280-1288.

The contracted Achilles tendon leads to increased forefoot pressure, thus increasing the risk for ulceration in neuropathic patients. Several studies have shown the benefit of Achilles tendon lengthening to heal and prevent forefoot ulceration in these patients. The flexor hallucis longus transfer is used for chronically torn/deficient Achilles tendons, not a contracted Achilles tendon. The Jones procedure works well for the first ray but does not help to alleviate pressure under the second ray. Peripheral bypass surgery is unnecessary because the ulcer healed during the initial treatment, indicating that the patient has adequate circulation. The posterior tibial tendon transfer is used for foot drop or other neuromuscular conditions to correct deformity and increase function. It is not used for forefoot ulcers in patients with diabetes mellitus. Armstrong DG, Stacpoole-Shea S, Nguyen H, et al: Lengthening of the Achilles tendon in diabetic patients who are at high risk for ulceration of the foot. J Bone Joint Surg Am 1999;81:535-538.

Streeter's dysplasia is clearly related to rupture of the amnion in utero and is now most commonly referred to as premature amnion rupture sequence. The deformities arise from amniotic bands that wrap about protruding parts and from uterine packing because of the accompanying oligohydramnios. Clubfoot can develop as a result of the latter mechanism. Three limb involvement is most commonly seen, along with syndactyly. Treatment involves resection of bands and Z-plasty of skin. The disease is not genetic and has not been related to teratogen exposure or to iatrogenic influences such as amniocentesis. Developmental field disruption is not seen in this disease, and the growth potential of the involved parts is normal unless neurovascular disruption has arisen from band formation.

The history, examination, and surgical findings are most consistent with plantar fibromatosis. Plantar fibromatosis is a benign tumor of the plantar fascia that consists chiefly of fibromyoblasts. These cells produce excessive collagen and are similar to the cells found in the palmar fascia of patients with Dupuytren's contracture of the hand. The myocyte, synovial cell, and osteocyte all produce their respective individual tissue types but do not contribute to the formation of a plantar fibromatosis. The T-cell is an important immunologic cell that is most affected in patients with HIV.

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

The radiograph shows widening between the scaphoid and lunate. The normal variance is up to 5 mm. Although several ligaments may be torn, the scapholunate interosseous ligament must be torn for this widening to occur. Cooney WP, Linscheid RL, Dobyns JH: The Wrist: Diagnosis and Operative Treatment. St Louis, MO, Mosby-Year Book, 1998, vol 1, pp 503-506.

The most commonly injured neurovascular structure during an anterior approach for the repair of a distal biceps tendon rupture is the lateral antebrachial cutaneous nerve. This structure is located lateral to the biceps tendon and in a superficial location just deep to the subcutaneous layer. The antecubital vein is medial and superficial with the brachial artery and median nerve also medial to the biceps tendon but deep to the common flexors. The posterior interosseous nerve is deep within the supinator muscle and can be injured in the deep dissection or through the posterior approach when using a two-incision approach. Kelly EW, Morrey BF, O'Driscoll SW: Complications of repair of the distal biceps tendon with the modified two-incision technique. J Bone Joint Surg Am 2000;82:1575-1581.

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

The radiographs show classic hinge abduction. The diagnostic feature is the failure of the lateral epiphysis to slide under the acetabular edge with abduction, and the abduction view shows medial dye pooling because of distraction of the hip joint. Persistent hinge abduction has been shown to prevent femoral head remodeling by the acetabulum. Radiographic changes are characteristic of severe involvement with Legg-Calve-Perthes disease.The Catterall classification cannot be well applied without a lateral radiograph, but this degree of involvement would likely be considered a grade III or IV. Because the lateral pillar is involved, this condition would be classified as type C using the Herring lateral pillar classification scheme.

Although relatively common in people of Asian origin, OPLL has been reported in other races as well. The radiographic appearance can be variable as there are different types described, but some of the discerning characteristics are seen in these images. On the sagittal view, the bone posterior to the vertebral body extends along the entire length of C2 and C3. This is characteristic of OPLL, whereas cervical spondylosis and DISH more commonly are not confluent. Ankylosing spondylitis more commonly extends significantly into the spinal canal, and neurofibromatosis generally does not cause any bony growth. The axial view shows a large, oval bony projection into the spinal canal, a typical finding of OPLL. McAfee PC, Regan JJ, Bohlman HH: Cervical cord compression from ossification of the posterior longitudinal ligament in non-orientals. J Bone Joint Surg Br 1987;69:569-575.

The prognosis of Legg-Perthes disease in children younger than age 6 years is good. There is no indication that surgical treatment will improve the outcome. Range-of-motion exercises to prevent contracture may be helpful. Herring JA, Kim HT, Browne R: Legg-Calve-Perthes disease: Prospective multicenter study of the effect of treatment on outcome. J Bone Joint Surg Am 2004;86:2121-2134.

Unlike compression-side stress fractures, tension-side stress fractures on the superior side of the femoral neck are at a very high risk of displacement, even if the patient is not bearing weight. It is highly recommended to treat these fractures like acute fractures and to proceed with internal fixation emergently. Once the fracture has displaced, the prognosis is poor in terms of returning to sports, even when reduced and internally fixed. Nonsurgical management, such as limited weight bearing and low-impact activities, works very well for other lower extremity stress fractures. A training program evaluation (shoes, tracks, schedule) is always indicated for all patients with stress fractures.

The fracture pattern shown in the radiographs is a fracture of the posterior column. The only line interrupted on the AP pelvis is the ilioischial line. The obturator oblique view shows that the iliopectineal line is intact as is the outline of the posterior wall. The iliac oblique view shows an interruption of the ilioischial line and an intact anterior wall. Therefore, this fracture is a fracture of the posterior column. Letournel E, Judet R: Fractures of the Acetabulum, ed 2. Berlin, Germany, Springer Verlag, 1993.

Evidence implicates an association, albeit unexplained, between Clostridium septicum infection and malignancy, particularly hematologic or intestinal malignancy. The malignancy is often at an advanced stage, compromising survival of the patients. A bowel portal of entry is postulated for most patients. In the absence of an external source in the patient with clostridial myonecrosis or sepsis, the cecum or distal ileum should be considered a likely site of infection. Increased awareness of this association between Clostridium septicum and malignancy, and aggressive surgical treatment, may result in improvement in the present 50% to 70% mortality rate. Other organisms associated with malignancy include group Clostridium streptococci that are occasionally associated with upper gastrointestinal malignancies. Schaaf RE, Jacobs N, Kelvin FM, et al: Clostridium septicum infection associated with colonic carcinoma and hematologic abnormality. Radiology 1980;137:625-627.

Transient osteoporosis is a self-limited painful but reversible disorder. Although first described in pregnant women, it is more common in young to middle-aged men. The radiograph shows loss of mineralization in the right hip relative to the left side. There is no osseous destruction or cortical expansion typical of metastasis or giant cell tumor. The process is confined to the femoral side of the joint unlike rheumatoid arthritis, which would be centered in the joint. Osteonecrosis is better defined with sharp but irregularly shaped margins, and there is no double-line sign. The MRI scans reveal diffuse edema in the femoral head and neck that is atypical for osteonecrosis. Transient osteoporosis may recur in the same or opposite hip.

The enthusiasm with which dorsal rhizotomy was received led to the broadening of selection criteria with poorer results. The ideal candidate is an ambulatory 4- to 8-year-old child with spastic diplegia who does not use assistive devices or have joint contractures. The child must be old enough to actively participate in the rigorous postoperative physical therapy program. The use of the procedure in an ambulatory 16-year-old patient is less desirable because joint contractures will most likely have developed to a varying degree. The hemiplegic child is best treated by orthopaedic interventions. Oppenheim WL: Selective posterior rhizotomy for spastic cerebral palsy: A review. Clin Orthop 1990;253:20-29. Renshaw TS, Green NE, Griffin PP, Root L: Cerebral palsy: Orthopaedic management. J Bone Joint Surg Am 1995;77:1590-1606.

Closed management should be attempted for upper extremity pathologic fractures, particularly the clavicle. If nonunion or pain persists, surgery may be indicated. Radiofrequency ablation is not indicated for subcutaneous bones. Early motion is likely to cause increased pain and disability. Weber KC, Lewis VO, Randall RL, Lee AK, Springfield D: An approach to the management of the patient with metastatic bone disease. Instr Course Lect 2004;53:663-676.

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

The radiographs and history are consistent with an acute unstable slipped capital femoral epiphysis. Aronson and Loder documented an increased rate of osteonecrosis associated with manipulative reduction. They recommended bed rest with skin traction to allow the synovitis to resolve, followed by in situ pinning. They noted, however, that many of these slips reduced with anesthesia and positioning on a fracture table. Biomechanic studies have shown a slight increased resistance to shear stress when two screws are used, but it is unknown if this is significant in the clinical setting. Open epiphyseodesis does not provide postoperative stability; therefore, adjunctive fixation or immobilization is required. Numerous studies have noted the inadvisability of using multiple screws. Casting has a high rate of complications, including chondrolysis and progression of the slip. Aronson DD, Loder RT: Treatment of the unstable (acute) slipped capital femoral epiphysis. Clin Orthop 1996;322:99-110. Karol LA, Doane RM, Cornicelli SF, Zak PA, Haut RC, Manoli A II: Single versus double screw fixation for treatment of slipped capital femoral epiphysis: A biomechanical analysis. J Pediatr Orthop 1992;12:741-745.

This is a nonossifying fibroma of the proximal tibia. The lesion is eccentric, cortically based, with sclerotic margins and no evidence of a soft-tissue mass. Nonossifying fibromas are benign lesions that need no biopsy or surgical treatment when classic findings appear on radiographs. A follow-up radiograph should be performed 2 to 3 months after the initial presentation to ensure that the lesion is not progressive. Surgery is reserved for large lesions with risk of pathologic fracture or for cases where a displaced pathologic fracture has occurred and internal fixation is needed for fracture treatment. Nondisplaced pathologic fractures through nonossifying fibromas are best treated by allowing the fracture to heal and observation of the lesion. Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 197-215.

Focal scleroderma is characterized by the formation of patches of sclerotic skin, also known as morphea, or streaks of sclerosis (linear scleroderma). Systemic involvement in focal scleroderma is unusual; however, progression during childhood is common. Contracture of underlying tissues is common, often resulting in serious joint contractures. Bony changes similar to those seen in melorheostosis can be seen. This patient has characteristic skin changes, atrophy of the soft tissues, Achilles tendon contractures, and calcaneal deformities. There are no signs of arthrogryposis, which usually presents with bilateral congenital deformities, including equinovarus. Klippel-Trenaunay-Weber syndrome is characterized by venous malformation in association with focal overgrowth.

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

The findings are characteristic of hemangioma. When the hemangioma is large enough, vertical striations may be visible on plain radiographs. Axial CT scans commonly reveal a speckled appearance. Metastatic lesions are typically hypointense on T1-weighted images because they replace the fatty marrow. Bony islands, like cortical bone, are dark on T1- and T2-weighted images. Intravertebral disk herniation would have characteristics similar to the disk and be in continuity with the disk. Osteoporosis is more diffuse. Ross JS, Masaryk TJ, Modic MT, Carter JR, Mapstone T, Dengel FH: Vertebral hemangiomas: MR imaging. Radiology 1987;165:165-169.

The lesion is a variation of a type I superior labrum anterior and posterior lesion; therefore, appropriate treatment is simple debridement. Biceps tenodesis or release is not indicated because the biceps tendon and anchor are intact. There is no indication for labral repair or capsulorraphy. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 261-270.

A 32-mm head design results in less linear wear but more volumetric wear particles. Modular components that allow motion between the polyethylene insert and the shell can result in backside wear. The oxidative degradation of gamma-irradiated polyethylene stored in air leads to increased wear. All of these factors lead to a greater particulate load and more osteolysis. Circumferential porous coating blocks ingrowth of particle-laden fluid and decreases osteolysis. Bartel DL, Bicknell VL, Wright TM: The effect of conformity, thickness, and material on stresses in ultra-high molecular weight components for total joint replacement. J Bone Joint Surg Am 1986;68:1041-1051. Fisher J, Hailey JL, Chan KL, et al: The effect of aging following irradiation on the wear of UHMWPE. Trans Orthop Res Soc 1995;20:12.

To improve hip biomechanics and secure more suitable bone for acetabular fixation, the true acetabulum is often resurfaced in patients who have developmental dysplasia of the hip, thus lowering the hip center and lengthening the leg. Acute lengthening of more than 3 cm will place excessive tension on the sciatic nerve and require a femoral shortening to avoid sciatic nerve injury. The other maneuvers will not relieve sciatic nerve tension because of limb lengthening. Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 430-431.

As shown by Palm and associates from the Hip Fracture Study group, the integrity of the lateral femoral cortex in intertrochanteric hip fractures is a significant predictor of reoperation. Baumgartner and associates have shown that a tip-apex distance of greater than 25 mm is associated with a high risk of femoral head cut-out. Lastly, intertrochanteric hip fractures can be described as standard obliquity or reverse obliquity when describing the fracture pattern. Mechanistically, a reverse obliquity pattern is important to recognize because it reflects the presence or absence of a lateral buttress to which the proximal fracture fragment may compress. Palm H, Jacobsen S, Sonne-Holm S, et al: Integrity of the lateral femoral wall in intertrochanteric hip fractures: An important predictor of a reoperation. J Bone Joint Surg Am 2007;89:470-475. Sadowski C, Lübbeke A, Saudan M, et al: Treatment of reverse oblique and transverse intertrochanteric fractures with use of an intramedullary nail or a 95 degrees screw-plate: A prospective, randomized study. J Bone Joint Surg Am 2002;84:372-381.

Isolated split posterior tendon transfer alone is best performed in a patient with cerebral palsy who is between the ages of 4 and 7 years and has a flexible equinovarus foot. Rigid deformities often must be managed with a combination of soft-tissue and bony procedures. Patients with out-of-phase activity may be best managed with a transfer of the posterior tibialis to the dorsum of the foot, while those with continuous activity are better candidates for an isolated split posterior tendon transfer. Drennan JC (ed): The Child's Foot and Ankle. New York, NY, Raven Press, 1992, pp 291-294. Green NE, Griffin PP, Shiavi R: Split posterior tibial-tendon transfer in cerebral palsy. J Bone Joint Surg Am 1983;65:748-754.

This lytic lesion is in the epiphyseal-metaphyseal region of the distal tibia. The most common lesion in this area is a giant cell tumor. Although these lesions are most commonly seen in adults, they can also occur in the skeletally immature patient. The photomicrograph shows a lesion with multiple giant cells, the nuclei of which are similar to those in the background stroma; this finding is characteristic of giant cell tumors. Giant cells can be seen in many benign lesions, including aneurysmal bone cysts, Brown tumors, and eosinophilic granuloma. These lesions usually have fewer giant cells with less nuclei. The location of this lesion in the epiphyseal-metaphyseal area is not seen in aneurysmal bone cysts, unicameral bone cysts, Ewing's sarcoma, or eosinophilic granuloma.

The patient has a bucket-handle fracture of the distal femur with bilateral corner fractures of the distal femur and a transverse fracture of the proximal tibia. These fractures are virtually pathognomonic of child abuse. The infant should be admitted to the hospital, and child protection services should be notified for investigation of possible abuse. A skeletal survey should be obtained, along with laboratory studies that include a CBC, a platelet count, a prothrombin time, a partial thromboplastin time, and a bleeding time. Akbarnia BA: The role of the orthopaedic surgeon in child abuse, in Morrissy RT, Weinstein SL (eds): Lovell & Winter's Pediatric Orthopaedics, ed 4. Philadelphia, Pa, Lippincott-Raven, 1996, pp 1315-1334.

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. 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.

Most soft-tissue sarcomas are treated with a combination of radiation therapy and wide resection. Rhabdomyosarcomas are an exception, where chemotherapy is included in all treatment plans. Chemotherapy for other soft-tissue sarcomas is controversial. Enzinger FM, Weiss SW: Rhabdomyosarcoma, in Soft Tissue Tumors, ed 3. St Louis, MO, CV Mosby, 1995, p 539.

The scoring system published by Mirels in 1989 is based on the following characteristics: the location of the lesion, the amount of pain the patient is experiencing, the type of lesion (either lucent, mixed, or blastic), and the lesion size. The tumor is scored from 1 to 3 in each category and a total score is obtained that correlates to fracture risk. Prophylactic fixation is advised for lesions with scores of higher than 8, and consideration for stabilization should be strongly considered for scores of 8. The Mirels scoring system can be useful as an adjunct to clinical decision making. Mirels H: Metastatic disease in long bones: A proposed scoring system for diagnosing impending pathologic fractures. 1989. Clin Orthop Relat Res 2003;415:S4-S13.

The radiographs show well-fixed components of a posterior cruciate-retaining total knee replacement. The relative position of the femoral component is anteriorly subluxated relative to the tibial component. The AP radiograph shows that the articular space is markedly asymmetric, indicating either failure or fracture of the polyethylene or subluxation of the femur relative to the tibia. The patient's symptoms suggest a failure of the posterior cruciate ligament that is consistent with the radiographic findings; therefore, the treatment of choice is revision to a posterior cruciate-substituting implant.

The examination findings reveal that there is specific involvement of the medial plantar nerve by the distribution of the pain medially. The symptoms exclude the possibility of plantar fasciitis and anterior tibial tendinitis. Sinus tarsi syndrome would produce anterolateral symptoms rather than medial symptoms. Rask MR: Medial plantar neurapraxia (jogger's foot): Report of three cases. Clin Orthop 1978;134:193-195. Murphy PC, Baxter DE: Nerve entrapment of the foot and ankle in runners. Clin Sports Med 1985;4:753-763.

Results show that patients who underwent humeral head replacement for fracture almost routinely report pain relief, but functional reports vary. The most commonly reported difficulty is the use of weight in the overhead position with wide variation in active elevation. Factors found to affect active elevation include age, humeral offset, greater tuberosity positioning, and four-part (as compared with three-part) fractures. Goldman RT, Koval KJ, Cuomo F, Gallagher MA, Zuckerman JD: Functional outcome after humeral head replacement for acute three- and fourth-part proximal humeral fractures. J Shoulder Elbow Surg 1995;4:81-86.

The compaction of FDBA is faster than that of fresh-frozen bone. The maximal stiffness reached by both materials when tested was the same (55 MPa), but the FDBA required fewer impactions to achieve that stiffness. Because it is easier to impact, the FDBA may be mechanically more efficient than the fresh-frozen bone in surgical conditions. The brittleness of irradiated FDBA, caused by loss of the capacity to absorb energy in a plastic way, increases the compactness and stiffness of morcellized grafts. The failure rate of fusion in adolescent idiopathic scoliosis has been shown to be much higher in FDBA than in either iliac crest bone graft or composite autograft with demineralized bone matrix. There is a greater erosive surface response to allograft when compared to autograft or frozen allograft, with a larger number of osteoclast and osteoblast nuclei seen microscopically. Cornu O, Libouton X, Naets B, et al: Freeze-dried irradiated bone brittleness improves compactness in an impaction bone grafting model. Acta Orthop Scand 2004;75:309-314. Price CT, Connolly JF, Carantzas AC, et al: Comparison of bone grafts for posterior spinal fusion in adolescent idiopathic scoliosis. Spine 2003;28:793-798.

Reverse oblique intertrochanteric femoral fractures account for 5% of all intertrochanteric or subtrochanteric fractures. They are uncommon but not rare and will be encountered in practice. The sliding hip screw is associated with the most problems because of its design. When reverse oblique fractures are fixed with a sliding hip screw, the action of the construct causes medial displacement of the distal fragment rather than compression of the proximal and distal fragments. All of the other implants prevent medial displacement of the distal segment. It should not be assumed that simply using one of the other implants is reason for success. There is a significant failure rate for each of these implants with reverse oblique fractures. The implant must be ideally placed and the fracture must be reduced. Haidukewych GJ, Israel TA, Berry DB: Reverse obliquity fractures of the intertrochanteric region of the femur. J Bone Joint Surg Am 2001;83:643-650. Sanders RW, Regazzoni P: Treatment of subtrochanteric femur fractures using the dynamic condylar screw. J Orthop Trauma 1989;3:206-213.

When a lateral condylectomy alone is performed for all bunionette deformities, a high recurrence rate is expected. Lateral condylectomy should be used alone when the primary deformity is an enlarged lateral condyle of the fifth metatarsal head. In cases with significant divergence of the fifth metatarsal shaft in relationship to the fourth metatarsal shaft or with lateral bowing of the distal fifth metatarsal shaft, the lateral fifth metatarsal prominence will not be effectively reduced and recurrent symptoms and deformity are expected. Transfer metatarsalgia and/or dislocation of the metatarsophalangeal joint can infrequently occur with excessive metatarsal head excision. Arthrosis of the metatarsophalangeal joint has not been frequently reported. Coughlin MJ, Mann RA: Keratotic disorders of the plantar skin, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, Mosby-Year Book, 1993, pp 413-465. Kelikian H: Deformities of the lesser toe, in Kelikian H (ed): Hallux Valgus, Allied Deformities of the Forefoot and Metatarsalgia. Philadelphia, PA, WB Saunders, 1965, pp 327-330.

The plain radiographs show a defect in the lateral femoral condyle and narrowing of the lateral joint space. The MRI scan shows a lesion consistent with osteonecrosis of the lateral femoral condyle. The treatment alternatives for this condition are an osteotomy or a total knee replacement, but a total knee replacement is the treatment of choice for a 72-year-old patient. Arthroscopy or an osteochondral bone graft will not address her symptoms. A valgus osteotomy will exacerbate the problem by overloading the lateral joint, which is already diseased. Lotke PA, Ecker ML: Osteonecrosis of the knee. J Bone Joint Surg Am 1988;70:470-473.

The MRI scan shows an ALPSA lesion. This is also known as a medialized Bankart with medial displacement of the torn anterior labrum. During surgical stabilization, the labrum and periosteal sleeve must be mobilized and repaired laterally to reduce recurrent instability. A Perthes lesion is a nondisplaced labral tear. A GLAD lesion represents a nondisplaced anterior labral tear with an associated articular cartilage injury. Neviaser TJ: The anterior labroligamentous periosteal sleeve avulsion lesion: A cause of anterior instability of the shoulder. Arthroscopy 1993;9:17-21.

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

Orthopaedic surgeons are often responsible for interpreting radiographs of general examinations such as the chest radiograph shown. For accurate interpretation, it is important to systematically review all of the information available on the radiograph. Using this approach, the fracture of the left proximal humerus is readily recognized. Linear air soft-tissue density at the lung periphery would suggest a pneumothorax, but this finding is not shown on the radiograph. The upper thoracic spine is well aligned. The sternoclavicular and distal clavicles are normal.

Although there are several bursae in the posterior portion of the knee, the most prevalent one with a connection to the knee joint is the one in the interval between the semimembranosus and the medial head of the gastrocnemius muscle. The popliteus muscle and posterior cruciate ligament, the posterior cruciate ligament and lateral gastrocnemius muscle, and the medial gastrocnemius muscle and posterior cruciate ligament are all too lateral and uncommon. The semitendinosus and medial head of the gastrocnemius muscles do not come in contact in the posterior aspect of the knee. Resnick D: Diagnosis of Bone and Joint Disorders, ed 3. Philadelphia, PA, WB Saunders, 1995, p 379.

The stiffness is most influenced by the geometry, in particular the diameter of the stem. The bending rigidity increases to the fourth power of the radius. The elastic modulus of the material increases as a direct linear relationship. The surface coating does not affect the bending rigidity greatly unless it increases the diameter significantly.

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

The patient's heart rate is not responding to hypotension with tachycardia, as would be expected in the event of hypovolemic shock. Additionally, the adequate urine output suggests proper fluid resuscitation. Instead, she is bradycardic, possibly indicating neurogenic shock and loss of sympathetic tone to the heart. A Swan-Ganz catheter should be used to help differentiate these problems and guide appropriate fluid resuscitation and use of vasopressor agents. Hadley MN: Management of acute spinal cord injuries in an intensive care unit or other monitored setting. Neurosurgery 2002;50:S51-S57.

Rejecting this proposal is the only appropriate course of action. Accepting it would, in essence, be receiving a huge gift from industry in the form of a sailboat. Physicians frequently assert that they are not influenced by gifts and relationships with industry representatives, but evidence is to the contrary. Such an arrangement constitutes a tremendous incentive to use the manufacturer's products. The fact that the boat partnership seems completely outside of the orthopaedic business relationship does not excuse it. Conflicts of interest should always be resolved and in the best interest of patient care, and in this case the best course clearly is to avoid the conflict of interest totally. An equal interest in the boat does not eliminate the conflict of interest. AAOS Standard of Professionalism -Orthopaedist -Industry Conflict of Interest (Adopted 4/18/07), Mandatory Standard numbers 6-8. www3.aaos.org/member/profcomp/SOPConflictsIndustry.pdf Opinions on Ethics and Professionalism: The Orthopaedic Surgeon's Relationship with Industry (Document 1204), in Guide to the Ethical Practice of Orthopaedic Surgery, ed 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2007, pp 36-40. www.aaos.org/about/papers/ethics/1204eth.asp AdvaMed Code of Ethics on Interactions with Health Care Professionals, Advanced Medical Technology Association, Washington, DC. www.AdvaMed.org