100 Orthopedic MCQs: Spine, Trauma, Adult Recon, Sports Med | Comprehensive ABOS Exam

Both the medial collateral ligament and the olecranon contribute to valgus stability of the elbow. Excessive olecranon resection increases the demand placed on the medial collateral ligament in resisting valgus forces during throwing. Bone removal from the olecranon should be limited to osteophytes. Garrick JG (ed): Orthopaedic Knowledge Update: Sports Medicine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 101-111.

The dislocation is between the medial and middle cuneiform. Although the first and second tarsometatarsal joints are aligned, there is a gap between the cuneiforms. The radiograph shows a Lisfranc dislocation variant. In a healthy active individual, open reduction and internal fixation yields the best results. The reestablishment of the normal arch and medial column support with anatomic reduction is critical to obtaining the best possible outcome from these injuries. Teng AL, Pinzur MS, Lomasney L, et al: Functional outcome following anatomic restoration of the tarsal-metatarsal fracture dislocation. Foot Ankle Int 2002;23:922-926.

The MRI scan reveals a lobular mass that is below the vitamin E tablet marker taped to the skin. This is juxtaposed to the tibialis anterior tendon. It is slightly more enhanced than the surrounding subcutaneous fat and is consistent with a ganglion. Osteosarcoma, aneurysmal bone cyst, or unicameral bone cyst all would demonstrate enhancement or pathology in the bone. This is clearly a well-defined soft-tissue mass. Gouty tophi show low to intermediate signal on T1- and T2-weighted images. Kransdorf MJ, Jelinek JS, Moser RP Jr, et al: Soft tissue masses: Diagnosis using MR imaging. Am J Roentgenol 1989;153:541-547. Wetzel LH, Levine E: Soft-tissue tumors of the foot: Value of MR imaging for specific diagnosis. Am J Roentgenol 1990;155:1025-1030.

The patient has a failed Silastic implant. Nonsurgical management will not work at this point. A Keller resection will only exacerbate her metatarsalgia. Implant removal with structural bone grafting and MTP fusion is the most appropriate choice because restoration of length is needed to alleviate the forefoot pain and bone grafting is required to fuse the MTP joint because there is an abundance of osteolysis. Total toe implants do not offer good long-term outcomes and are very difficult to fit into the large exploded-out cavity of the proximal phalanx. Hecht PJ, Gibbons MJ, Wapner KL, et al: Arthrodesis of the first metatarsophalangeal joint to salvage failed silicone implant arthroplasty. Foot Ankle Int 1997;18:383-390.

The most common causes of patellar instability after total knee arthroplasty are valgus malalignment, internal rotation of the femoral or tibial component, medialization of the femoral component, errors in patellar preparation and resurfacing, and failure to perform a lateral release. These factors should be addressed before considering capsular closure. Distal extensor mechanism realignment should be avoided because of the complication rate. The proximal extensor mechanism would not adequately compensate for implant malrotation. Barnes CL, Scott RD: Patellofemoral complications of total knee replacement, in Heckman JD (ed): Instructional Course Lectures 42. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1993, pp 309-314.

The magnitude of the curve at the time of the peak height velocity is the most prognostic sign in relationship to surgery. More than 70% of curves that measure more than 30 degrees at this time are likely to reach surgical range. Little DG, Song KM, Katz D, et al: Relationship of peak height velocity to other maturity indicators in idiopathic scoliosis in girls. J Bone Joint Surg Am 2000;82:685-693.

The patient has a persistent diabetic foot ulcer without evidence of osteomyelitis. He has evidence of a sensory peripheral neuropathy and a concomitant motor neuropathy, leading to a dynamic motor imbalance. Use of a total contact cast would offer a high probability of healing the resistant ulcer but with a high potential for recurrence. Combining the total contact cast with Achilles tendon lengthening allows wound healing without a high risk for recurrence. Excision of the noninfected metatarsal head would make the patient vulnerable to the development of a transfer lesion under one of the remaining metatarsal heads. Robertson DD, Mueller MJ, Smith KE, et al: Structural changes in the forefoot of individuals with diabetes and a prior plantar ulcer. J Bone Joint Surg Am 2002;84:1395-1404.

Mapping of a physeal bar from biplane polytomography or CT helps to identify lesions that should be treated surgically and aids in planning the surgical approach and resection. Criteria for surgical excision are at least 2 years of longitudinal growth remaining and involvement of no more than 50% of the physis. Osteotomy is required if angular deformity is greater than 20 degrees. Although this physeal bar is large, it is slightly less than 50% of the total area of the physis. Limb lengthening in this case should be reserved for failure of bar resection. Physiodesis of the opposite distal tibia at this age would result in disproportionate shortening of both tibiae. Carlson WO, Wenger DR: A mapping method to prepare for surgical excision of a partial physeal arrest. J Pediatr Orthop 1984;4:232-238.

Dislocation following total hip arthroplasty is twice as common in women than in men. It is more likely to occur in older patients. There is no clear association between dislocation and the method of fixation or the type of bearing, so long as the bearing diameter is the same.

Multidirectional instability of the shoulder is defined as symptomatic instability in two or more directions (anterior, posterior) but must include a component of inferior instability. Initial treatment should always include physical therapy and instruction in a home exercise program that emphasizes periscapular and rotator cuff strengthening to improve the dynamic stability of the glenohumeral joint. Immobilization has not been shown to be effective. Open capsular shift and arthroscopic capsular plication remain the surgical options when appropriate nonsurgical management fails (typically a minimum of 6 months of dedicated therapy and home program). Thermal capsulorrhaphy remains controversial but is not recommended by many clinicians because of reported complications including recurrent instability, axillary nerve injury, chondrolysis, and capsular injury. Neer CS II, Foster CR: Inferior capsular shift for involuntary inferior and multidirectional instability of the shoulder: A preliminary report. J Bone Joint Surg Am 1980;62:897-908. D'Alessandro DF, Bradley JP, Fleischli JE, et al: Prospective evaluation of thermal capsulorrhaphy for shoulder instability: Indications and results, two- to five-year follow-up. Am J Sports Med 2004;32:21-33. Levine WN, Clark AM Jr, D'Alessandro DF, et al: Chondrolysis following arthroscopic thermal capsulorrhaphy to treat shoulder instability: A report of two cases. J Bone Joint Surg Am 2005;87:616-621.

Small vesicles on the fingers of a health care worker suggest a herpetic infection, and the management of choice is observation. Incision and drainage may result in a bacterial infection. Marsupialization is used in the treatment of a chronic paronychia. Calcium gluconate is used for hydrofluoric acid burns, and copper sulfate is used for white phosphorus burns. Fowler JR: Viral Infections. Hand Clin 1989;5:613-627.

Two recent studies by Pollak and associates and Marsh and associates have focused on function after high-energy tibial plafond fractures. Findings are unfavorable even when anatomic reduction is performed in the best centers and patients are provided excellent rehabilitation. Function improves up to 2 years after injury, but even basic walking skills remain adversely affected. Virtually all patients have long-term adverse general health effects compared to their gender and age-matched peers. Posttraumatic degenerative arthritis is present in most ankles. Patients should be told early about the long-term prognosis, and early vocational/psychological counseling should be given. Despite these adverse outcomes, only a minority of patients require fusion or arthroplasty. Pollak AN, McCarthy ML, Bess RS, et al: Outcomes after treatment of high-energy tibial plafond fractures. J Bone Joint Surg Am 2003;85:1893-1900.

Because the patient is critically ill and requires expeditious care, stabilization of the long bone fracture is required, but definitive care of the fracture should be postponed. The treatment of choice at this time is irrigation with 12 L of saline solution, followed by debridement and nondefinitive stabilization with a simple four-pin external frame to regain axial and rotational alignment. When the patient's condition is more stable, more definitive care can be performed. Bosse MJ, Kellam JF: Orthopaedic management decisions in the multiple trauma patient, in Browner BD, Jupiter JP, Levine AM, Trafton P (eds): Skeletal Trauma, ed 2. Philadelphia, PA, WB Saunders, 1998, pp 151-164. Weresh MJ, Stover MD, Bosse MJ, Jeray K, Kellam JF: Pulmonary gas exchange during intramedullary fixation of femoral shaft fractures. J Trauma 1999;46:863-868.

Unicompartmental arthroplasty of the knee for single compartment arthrosis has recently become more popular. Contraindications to unicompartmental knee arthroplasty include fixed varus or valgus deformity of more than 5 degrees, restricted range of motion, fixed flexion contracture, joint subluxation of 5 mm or greater, and arthrosis of the opposite and/or patellofemoral compartment. Cossey AJ, Spriggins AJ: The use of computer-assisted surgical navigation to prevent malalignment in unicompartmental knee arthroplasty. J Arthroplasty 2005;20:29-34. Iorio R, Healy WL: Unicompartmental arthritis of the knee. J Bone Joint Surg Am 2003;85:1351-1364.

Progressive hip subluxation occurs in up to 50% of children with spastic quadriparesis. The subluxation is the result of chronic muscle hypertonicity, especially in the adductor muscle group. In time, the constant muscle tension will lead to dislocation, dysplastic changes in the acetabulum, and erosive changes in the cartilage of the femoral head. Many of these children will experience pain. Two recent studies have shown that early soft-tissue releases can successfully prevent progressive subluxation in children who are younger than age 4 years and who have a Reimers index (migration index) of less than 40%. Botulinum toxin A injections may reduce tone in the adductors for 4 to 6 months, but it is difficult to inject into the iliopsoas. Additionally, there are no long-term studies documenting the efficacy of botulinum toxin A to treat progressive hip subluxation in patients who have spastic quadriparesis. In general, proximal femoral osteotomy, combined with soft-tissue release as necessary, is indicated in older children (older than age 4 years) with progressive subluxation. Although selective dorsal rhizotomy has been used in nonambulatory patients, outcomes are less well documented than in ambulatory patients. There are no studies documenting the effect of selective dorsal rhizotomy on progressive hip subluxation in nonambulatory children. Miller F, Cardoso Dias R, Dabney KW, et al: Soft-tissue release for spastic hip subluxation in cerebral palsy. J Pediatr Orthop 1997;17:571-584.

This is an example of tethering of the flexor hallucis longus/flexor digitorum longus (FHL/FDL) to the fracture site. Additional time and/or physical therapy and bracing would not be expected to be of benefit. Release of the FHL and FDL from the fracture site or retromalleolar lengthening will address the posttraumatic claw toe deformity and Achilles tendon lengthening will address the mild equinus. Posterior tibial tendon transfer is not appropriate as the patient demonstrates a normal heel rise. Midfoot releases and hallux fusion are also not indicated. Feeny MS, Williams RL, Stephens MM: Selective lengthening of the proximal flexor tendon in the management of acquired claw toes. J Bone Joint Surg Br 2001;83:335-338.

Persistent Horner's sign (ptosis, myosis, and anhydrosis) is a sign of proximal injury, usually avulsion of the roots from the cord which disrupts the sympathetic chain. Root rupture or avulsion proximal to the myelin sheath has less chance of healing. Two-month-old infants with persistent weakness in the other areas described may still have a good prognosis for recovery. Concurrent clavicle fracture has been shown to have no prognostic value. Clarke HM, Curtis CG: An approach to obstetrical brachial plexus injuries. Hand Clin 1995;11:563-581.

Spinal muscular atrophy is caused by an abnormal survival motor neuron gene that prevents apoptosis of the motor nerves. Spinal fusion results in better sitting balance, stabilized or improved pulmonary function, and high parental satisfaction, but it may result in at least temporary loss of upper extremity function. Bentley G, Haddad F, Bull TM, Seingry D: The treatment of scoliosis in muscular dystrophy using modified Luque and Harrington-Luque instrumentation. J Bone Joint Surg Br 2001;83:22-28. Furumasu J, Swank SM, Brown JC, Gilgoff I, Warath S, Zeller J: Functional activities in spinal muscular atrophy patients after spinal fusion. Spine 1989;14:771-775.

The patient has a type I (Hahn-Steinthal) capitellar fracture that is best seen on the lateral radiograph. If a fracture fragment is seen proximal to the radial head, a capitellar fracture is the most likely injury because radial head fractures do not migrate proximally. The fragment is large enough for fixation. Excision is the preferred treatment for small shear osteochondral type II (Kocher-Lorenz) capitellar fractures. Closed reduction usually is not successful because of rotation of the displaced fragment. Mehdian H, McKee M: Management of proximal and distal humerus fractures. Orthop Clin North Am 2000;31:115-127.

Reiter's syndrome is a seronegative spondyloarthropathy characterized most commonly by a triad of asymmetric arthritis, urethritis, and uveitis. Tendon ensethopathies can also be present. It is most often seen in men and is associated with a positive HLA-B27 marker. Rheumatoid arthritis does not usually present with these features; more commonly it causes forefoot pain and synovitis of the metatarsophalangeal joints. A CBC count with differential would be helpful in a situation of possible infection. The urethral swab would help to diagnose a gonococcal infection which can cause a monoarticular septic arthritis. Antiphospholipid antibody is associated with a hypercoaguable state and increased risk of deep venous thrombosis.

In a cadaver ligament sectioning study, the posterior capsular ligament was considered the most important structure for anterior-posterior stability of the sternoclavicular joint. The anterior capsular ligament also helps prevent anterior displacement but not to the same degree as the posterior ligament. The interclavicular ligament provides little support for anteroposterior translation. Spencer EE, Kuhn JE, Huston LJ, et al: Ligamentous restraints to anterior and posterior translation of the sternoclavicular joint. J Shoulder Elbow Surg 2002;11:43-47.

The 5-year overall survival rate for deep, high-grade soft-tissue sarcomas is around 50%. The overall survival and disease-free survival rates chiefly depend on the tumor stage, but for all stages combined, most cancer treatment centers report a 5-year overall survival rate of around 70% and a disease-free survival rate of 65%. Fleming ID, et al: Manual for Staging of Cancer/American Joint Committee on Cancer, ed 5. Philadelphia, PA, Lippincott Raven, 1997, pp 149-156.

Both cemented and cementless total knee arthroplasties depend on adequate fixation of the tibial component to promote long-term survivorship. An effective stem and adequate peripheral fixation of the tibial component to the cancellous-cortical portion of the proximal tibia are necessary for cementless fixation. Peripheral screws and pegs can serve as adjunctive fixation to decrease micromotion and shear forces and allow bone ingrowth to occur. Careful preparation of the proximal tibial surface can minimize fixation failure. Cemented fixation of the tibial stem should be performed in addition to the plateau. Osteolysis, polyethylene wear, and failure at the insert/tray locking mechanism have not occurred. Posterior cruciate ligament retention has not caused the tibial component fixation failure.

Paucytopenia is a common problem in patients with metastatic disease. Causes include chemotherapy, external beam radiation, marrow replacement by tumor, and anemia of chronic disease. There is no correlation with decreased calcium and a decrease in hematopoiesis. Supportive care with granulocyte-colony stimulating factor (G-CSF) and neupogen can stimulate hematopoiesis.

Pain is very common but is often nonspecific; therefore, the diagnosis of spinal infection is often delayed. Fever and sepsis can occur but are not common. Neurologic manifestations also can occur but are absent in most patients. In findings reported by Carragee, the urinary tract is a common source for hematogenous spinal infection, but the source was found in only 27% of 111 patients. Direct inoculation during spinal surgery is uncommon. Carragee EJ: Pyogenic vertebral osteomyelitis. J Bone Joint Surg Am 1997;79:874-880. Frazier DD, Campbell DR, Garvey TA, et al: Fungal infections of the spine: Report of eleven patients with long-term follow-up. J Bone Joint Surg Am 2001;83:560-565.

Any large (greater than 5 cm), deep, heterogeneous mass in the extremities should be considered a sarcoma until proven otherwise. Sarcomas are rare, and without a high index of suspicion, the lesions may be misdiagnosed or there may be a delay in diagnosis. Needle biopsies can obtain sufficient tissue for diagnosis and are associated with less morbidity than open biopsy. Marginal resections or excisional biopsies should be reserved for a few select benign lesions and locations. Damron TA, Beauchamp CP, Rougraff BT, et al: Soft-tissue lumps and bumps. Instr Course Lect 2004;53:625-637.

The nerve to the abductor digiti quinti is the first branch of the lateral plantar nerve. It branches off while the nerve is still on the medial side of the foot and also innervates a portion of the plantar fascia. It can become entrapped beneath the deep fascia of the abductor hallucis muscle and has been associated with some forms of chronic heel pain. Baxter DE, Pfeffer GB: Treatment of chronic heel pain by surgical release of the first branch of the lateral plantar nerve. Clin Orthop 1992;279:229-236.

The radiograph reveals a Crowe IV deformity in a patient with developmental dysplasia of the hip. If hip arthroplasty is performed, then some degree of limb lengthening is anticipated. Excessive limb lengthening can result in sciatic nerve palsy in these patients. The peroneal branch of the sciatic nerve is most often affected. Of the muscles listed, only the extensor hallucis longus is innervated by the peroneal branch of the sciatic nerve. Eggli S, Hankemayer S, Muller ME: Nerve palsy after leg lengthening in total replacement arthroplasty for developmental dysplasia of the hip. J Bone Joint Surg Br 1999;81:843-845.

The spinal cord and spinal canal undergo dynamic changes during neck flexion and extension. In neck flexion, the spinal cord initially unfolds and then undergoes elastic deformation with full flexion; the spinal canal lengthens. This may explain the presence of Lhermitte's sign as the cord is pulled anteriorly over an anterior osteophyte or disk, generating a compressive force on the spinal cord. During neck extension, the spinal cord relaxes (folding like an accordion) and the spinal canal shortens. Breig A: Biomechanics of the Central Nervous System: Some Basic Normal and Pathologic Phenomena. Stockholm, Sweden, Almquist and Wiksell, 1960.

Most patients with a significant recurrent neuroma will not obtain relief with conservative methods. Pain results from a stump neuroma at the weight-bearing area from too short of a resection of the nerve or from regrowth of the remaining nerve end. Although steroid injection may be helpful in localizing symptoms or providing temporary relief, it rarely cures a stump neuroma. Orthotics with a metatarsal pad will likely increase pressure and pain at the neuroma site. Physical therapy could temporize the symptoms but will not address the underlying problem. Similarly, bone decompression alone will not alter the location of the neuroma stump. Revision of the nerve to a more proximal level off of the weight-bearing area is the most likely method to succeed. A plantar approach facilitates identification and ability to revise the nerve to a more proximal level. Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 101-111. Johnson JE, Johnson KA, Unni KK: Persistent pain after excision of an interdigital neuroma: Results of reoperation. J Bone Joint Surg Am 1988;70:651-657. Beskin JL, Baxter DE: Recurrent pain following interdigital neurectomy: A plantar approach. Foot Ankle 1988;9:34-39.

The patient's findings are consistent with an intermediate form of spinal muscular atrophy. Children with this condition appear normal at birth but are not able to walk. The disorder affects anterior horn cells. Fasciculations may be present, but deep tendon reflexes are typically absent. The development of scoliosis is almost universal with this type of spinal muscular atrophy. More than 90% of patients with spinal muscular atrophy have deletions in the telomeric survival motor neuron gene. Peripheral myelin protein 22 is abnormal in Charcot-Marie-Tooth type IA. Connexin 32 is abnormal in the X-linked type of Charcot-Marie-Tooth disease. Neurofibromin is affected in neurofibromatosis type 1. Friedreich's ataxia is secondary to a disorder of frataxin. Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 111-131.

Breech positioning has been noted as the risk factor that most increases the relative risk of developmental dysplasia of the hip in multiple series and meta-analysis. All the other factors also increase the risk but to a lesser magnitude. 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.

Differentiating between a midfoot sprain and Lisfranc diastasis is critical in the management of the athlete with an acute injury to the midfoot. Greater than 2 mm of displacement between the first and second metatarsals on a weight-bearing radiograph is an indication for anatomic reduction with internal fixation of the tarsometatarsal joints. If no subluxation is noted, treatment should consist of a non-weight-bearing cast for 6 weeks, followed by a gradual return to activity. Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 39-54.

The injury pattern is that of a burst fracture at L1 contiguous with a compression fracture at T12. There is associated kyphosis and slight spondylolisthesis of T12 on L1. Treatment of this type of burst fracture in neurologically intact patients is somewhat controversial, with at least one study demonstrating equal long-term results comparing nonsurgical treatment to surgical treatment. In this study, however, body casts were used initially in the nonsurgical group. Moreover, because this patient has multiple fractures, spinal fracture stabilization should be considered to facilitate early mobilization. Surgical stabilization and fusion via a posterior approach is the best treatment option in this patient. Anterior decompression is not necessary since the patient is neurologically intact. McLain RF, Benson DR: Urgent surgical stabilization of spinal fractures in polytrauma patients. Spine 1999;24:1646-1654. Wood K, Butterman G, Mehbod A, et al: Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit: A prospective, randomized study. J Bone Joint Surg Am 2003;85:773-781.

Based on the epiphyseal location and sharp, well-defined borders, the radiograph suggests chondroblastoma. Histologically, multinucleated giant cells are scattered among mononuclear cells. The nuclei are homogenous and contain a characteristic longitudinal groove. Although not seen here, "chicken-wire calcification" with a bland giant cell-rich matrix is also typical for chondroblastoma. Clear cell chondrosarcoma occurs in epiphyseal locations but has a more aggressive histologic pattern and occurs in an older age group. Giant cell tumors occur in the epiphysis but have a more uniform giant cell population histologically. Aneurysmal bone cyst often results in bone remodeling and has a different pathologic appearance. Osteonecrosis has a typical histologic pattern of empty lacunae and necrotic bone. Springfield DS, Capanna R, Gherlinzoni F, et al: Chondroblastoma: A review of seventy cases. J Bone Joint Surg Am 1985;67:748-755. Simon M, Springfield D, et al: Chrondroblastoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 190.

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.

Elbow release and triceps transfer to restore motion can be performed in children who are age 4 years and older. The ability to flex the elbow either actively or passively is of great assistance in activities of daily living. Van Heest A, Waters PM, Simmons BP: Surgical treatment of arthrogrypsosis of the elbow. J Hand Surg Am 1998;23:1063-1070.

Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm. Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.

The radiograph reveals diffuse osteopenia and areas in the proximal femora that are moth-eaten in appearance. The extent of the marrow-replacing process is evident on the MRI scans, which reveal signal abnormality throughout the entire pelvis and both proximal femora. This represents a marrow-packing process, of which multiple myeloma is the best choice. This diagnosis is also supported by the anemia noted on the patient's history. Metastatic carcinoma and lymphoma also may have a similar presentation.

In a traditional plate system, fracture security depends on the friction between the plate and the underlying bone. Bicortical fixation will decrease the toggle and improve stability. Locking plates absorb axial forces transmitted from the screws. Such plates do not require plate compression against the bone, thus preserving periosteal blood supply. Nana AD, Joshi A, Lichtman DM: Plating of the distal radius. J Am Acad Orthop Surg 2005;13:159-171.

The patient has heterotopic ossification, a more common finding in patients who have sustained head injuries. Treatment will require removal of the heterotopic bone and anterior and posterior capsulectomies. The main concern about timing is the possible recurrence of heterotopic bone. While an extended wait was once thought necessary, this is no longer true. The timing is based on the time since injury and evidence of bone maturation on plain radiographs. A sharp marginal demarcation of the new bone and a trabecular pattern within it are usually present 3 to 6 months after onset, indicating that it is safe to proceed with surgical excision. It is not necessary to wait more than 6 months. Bone scan results are not good indicators because they may remain "hot" for long periods of time. The levels of alkaline phosphatase and serum calcium-phosphorus product do not need to be measured.

The coronal MRI scan of the wrist shows the scaphoid. There is a subtle fracture line with a step-off at the radial surface consistent with a nonunion. The signal intensity is markedly different between the two fragments of the scaphoid. This strongly suggests osteonecrosis. Preiser's disease is osteonecrosis typically involving most or all of the scaphoid. Kienbock's disease involves the lunate. Intraosseous ganglia are easily diagnosed on MRI but typically have a fluid-filled area surrounded by denser bone in the periphery. Scapholunate dissociation can be seen on MRI as an injury to the scapholunate ligament and widening of the scapholunate interval, neither of which is seen on this image.

Biomechanical ligament sectioning studies have implicated both the superior glenohumeral and coracohumeral ligaments as restraints to inferior translation when the shoulder is in 0 degrees of abduction and neutral rotation. Although there is controversy over the significance of each ligament, both are involved to some degree. The middle glenohumeral ligament is more important in the midranges of abduction, and the inferior ligament is more important at 90 degrees of abduction. The coracoacromial and coracoclavicular ligaments play no role in glenohumeral restraint. Warner JJ, Deng XH, Warren RF, et al: Static capsuloligamentous restraints to superior-inferior translation of the glenohumeral joint. Am J Sports Med 1992;20:675-685.

The stretched peroneus brevis muscle and tendon follow anterior to the fibula and are most likely incarcerated with reduction. The anterior talofibular ligament is too small to prevent reduction of the ankle joint itself. The extensor digitorum brevis originates from the talus; therefore, it is not involved in the tibiotalar joint. The posterior tibial tendon lies medially and would not be interposed into the ankle joint. Similarly, the anterior tibialis tendon also would not be involved. Pehlivan O, Akmaz I, Solakoglu C, et al: Medial peritalar dislocation. Arch Orthop Trauma Surg 2002;122:541-543.

Dense pods of ingrowth into the porous coating of cementless ingrowth sockets are seen. Channels through the non-ingrown portion allow access to the trabecular bone of the ilium. Polyethylene wear debris can enter these areas through screw holes. Expansile, lytic lesions can result, which can become large without compromising implant fixation. Loosening is late and results from catastrophic loss of bone. A well-fixed acetabular component with a modular design, a well-designed locking mechanism, and a good survivorship history is a candidate for exchange of the liner and grafting of the osteolytic lesion. Ries MD: Complications in primary total hip arthroplasty: Avoidance and management. Wear. Instr Course Lect 2003;52:257-265. Dumbleton JH, Manley MT, Edidin AA: A literature review of the association between wear rate and osteolysis in total hip arthroplasty. J Arthroplasty 2002;17:649-661.

Progressive weakness is a common sign with a large differential diagnosis. Nerve, muscle, and joint problems should be excluded when a patient has diffuse weakness and atrophy. Fascioscapulohumeral dystrophy is a rare disease characterized by facial muscle weakness and proximal shoulder muscle weakness. The weakness is usually bilateral, and scapular winging is common. If the scapular winging becomes pronounced, elevation of the shoulder can be affected. In severe cases, scapulothoracic fusion or pectoralis muscle transfer to the scapula may be indicated. Duchenne muscular dystrophy is typically severe and progressive. The other diagnoses are not compatible with the history or the physical findings. Shapiro F, Specht L: The diagnosis and orthopaedic treatment of inherited muscular diseases of childhood. J Bone Joint Surg Am 1993;75:439-454.

The sagittal and axial CT scans show a bilateral spondylolysis at L5. The defect is in the pars interarticularis on the right side but at the base of the pedicle on the left. Having failed a trial of physical therapy with only a 3-month history of pain, the next most appropriate step in management should consist of activity modification and bracing in an antilordotic lumbosacral orthosis. Surgical intervention is reserved for patients who have failed to respond to a trial of bracing and activity restriction. Debnath UK, Freeman BJ, Grevitt MP, et al: Clinical outcome of symptomatic unilateral stress injuries of the lumbar pars interarticularis. Spine 2007;32:995-1000.

The theoretic total knee components will resist anteroposterior motion by making the femoral component "climb the walls" of the tibial component. As drawn, there is no constraint to medial-lateral translation. The cylinder is not rounded on the edges, so varus-valgus motion will impart load from the cylinder to the trough over a small area, thus having a high contact stress.

The radiographs do not show significant arthrosis of the hallux metatarsophalangeal joint; therefore, arthrodesis is unnecessary. Orthotics will not correct the deformity. A distally based osteotomy will not achieve sufficient correction of the incongruity of deformity, and a Keller resection is not indicated in the younger population. The treatment of choice is a proximal metatarsal osteotomy with second toe correction.

The debate between reamed versus unreamed intramedullary nailing of the tibia continues. Although unreamed nailing was proposed for open fractures to minimize infection, its simplicity made it appealing for closed fractures. However, most studies to date show that the only advantage of unreamed nailing is less surgical time. All studies show higher nonunion rates with increased hardware failure and increased time to union for unreamed nailing. Even in open fractures graded up to Gustilo Grade IIIA, the reamed tibial nail performs better. Larsen LB, Madsen JE, Hoiness PR, et al: Should insertion of intramedullary nails for tibial fractures be with or without reaming? A prospective, randomized study with 3.8 years' follow-up. J Orthop Trauma 2004;18:144-149.

The most common causes of posterior ankle pain in ballet dancers are flexor hallucis longus tenosynovitis and os trigonum syndrome. Flexor hallucis longus tenosynovitis differs from a symptomatic os trigonum by the absence of pain with forced plantar flexion and the presence of pain with resisted plantar flexion of the great toe. The pain is often felt in the posterior ankle and can be associated with a snapping or triggering sensation. Os trigonum syndrome commonly occurs in ballet dancers who perform in a position of extreme plantar flexion. The pain occurs from entrapment of the os trigonum between the posterior portion of the talus and calcaneus. Hamilton WG, Geppert MJ, Thompson FM: Pain in the posterior aspect of the ankle in dancers: Differential diagnosis and operative treatment. J Bone Joint Surg Am 1996;78:1491-1500.

Fractures above and below the elbow constitute floating elbow injuries and are best treated with internal fixation to allow early range of motion and to prevent elbow stiffness. Use of a long arm cast would promote elbow stiffness. External fixation is indicated primarily for open injuries. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.

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.

Pagnano and associates revised 25 painful primary posterior cruciate-retaining total knee arthroplasties for flexion instability. The patients shared typical clinical presentations that included a sense of instability without frank giving way, recurrent knee joint effusion, soft-tissue tenderness involving the pes anserine tendons and the retinacular tissue, posterior instability of 2+ or 3+ with a posterior drawer or a posterior sag sign at 90 degrees of flexion, and above-average motion of the total knee arthroplasty. Twenty-two of the knee replacements were revised to posterior stabilized implants, and three underwent tibial polyethylene liner exchange only. Nineteen of the 22 knee replacements revised to a posterior stabilized implant showed marked improvement after the revision surgery. Only one of the three knee replacements that underwent tibial polyethylene exchange was improved. Flexion instability can be a cause of persistent pain and functional impairment after posterior cruciate-retaining total knee arthroplasty. Revision surgery that focuses on balancing the flexion and extension spaces, in conjunction with a posterior stabilized knee implant, seems to be a reliable treatment for symptomatic flexion instability after posterior cruciate-retaining total knee arthroplasty.

The patient has a grade I isthmic spondylolisthesis at L5-S1. He has an L5 radiculopathy with foraminal stenosis. Any further treatment needs to include an arthrodesis and foraminal decompression. Isolated interbody fusion is contraindicated in patients with spondylolisthesis, as is total disk arthroplasty. Therefore, the best procedure is a posterior fusion with instrumentation and bone graft along with a foraminal decompression. Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 311-317.

The dynamic forces acting to maintain the position of the proximal phalanx at the head of the metatarsal are a balance between the extensor digitorum longus and the weaker intrinsic muscles. With hyperextension at the metatarsophalangeal joint, the intrinsic muscles become less efficient as plantar flexors. Consequently, the hyperextension deformity progresses in the metatarsophalangeal joint as the opposition of the intrinsic muscles to the extensor tendon lessens. This is in contrast to the situation in the interphalangeal joints, where the stronger flexors overpower the weaker intrinsic muscles, which act as the extensors. This combination of events leads to hyperextension at the metatarsophalangeal joint and flexion deformities at the interphalangeal joints, resulting in claw toe. Mizel MS, Yodlowski ML: Disorders of the lesser metatarsophalangeal Joints. J Am Acad Orthop Surg 1995;3:166-173.

The gunshot wound has caused injury to multiple systems: bone, vascular, skin, and tendon; therefore, the treatment of choice is amputation. An immediate ray amputation allows for a more rapid return to activities and less time off work. Peimer CA, Wheeler DR, Barrett A, et al: Hand function following single ray amputation. J Hand Surg Am 1999;24:1245-1248.

Adequate decompression of the cervical cord can be achieved in a variety of ways depending on the pathoanatomy of the compression, but kyphosis is a relative contraindication to laminectomy alone. For laminectomy to be effective, the lordosis must be maintained so the cord can displace posteriorly away from the anterior structures. In addition, removing the posterior tension band increases the probability that the kyphosis will progress, therefore increasing the force against the front of the cord as it tents across the kyphosis. Albert TJ, Vaccaro A: Postlaminectomy kyphosis. Spine 1998;23:2738-2745. Truumees E, Herkowitz HN: Cervical spondylotic myelopathy and radiculopthy. Instr Course Lect 2000;49:339-360.

The pectoralis major insertion is just lateral to the long head of the biceps tendon. Medial to the biceps is the insertion for the teres major and latissimus dorsi. The short head of the biceps originates on the coracoid process. The subscapularis inserts on the lesser tuberosity just medial to the biceps.

The clinical presentation soon after injury may be surprisingly innocuous, but all high-pressure injection injuries of various materials are best treated by emergent surgical debridement of all foreign material from the flexor tendon sheath as well as the subcutaneous tissues. Subsequent hospital admission, IV antibiotics, and possible repeat debridements usually are necessary. The use of antibiotics alone is inadequate treatment of this severe injury. Pinto MR, Turkula-Pinto LE, Cooney WP, Wood MB, Dobyns JH: High-pressure injection injuries of the hand: Review of 25 patients managed by open wound technique. J Hand Surg Am 1993;18:125-130. Urbaniak JR, Evans JP, Bright DS: Microvascular management of ring avulsion injuries. J Hand Surg Am 1981;6:25-30. Tsai TM, Manstein C, DuBou R, Wolff T, Kutz JE, Kleinert HE: Primary microsurgical repair of ring avulsion amputation injuries. J Hand Surg Am 1984;9:68-72. Kay S, Werntz J, Wolff T: Ring avulsion injuries: Classification and prognosis. J Hand Surg Am 1989;14:204-213.

Passive glycation of articular cartilage occurs over decades. One of the consequences of this glycation appears to be the stiffening of collagen. This phenomenon appears to be associated with an increased collagen degradation and development of osteoarthrosis. Passive glycation also results in a relatively yellow appearance. Passive glycation does not directly influence chondrocyte proliferation. DeGroot J, Verzijl N, Wenting-van Wijk MJ, et al: Accumulation of advanced glycation end products as a molecular mechanism for aging as a risk factor in osteoarthritis. Arthritis Rheum 2004;50:1207-1215.

Although technically challenging, the Ganz periacetabular osteotomy offers advantages over other rotational pelvic osteotomies. Posterior column integrity is maintained, as is the acetabular vascular supply. Free mobility of the fragment makes large corrections in the center edge angle possible. Because of the asymmetric cuts and the need to restore anterior coverage, there is a tendency to anterior displacement of the joint while flexing the acetabulum. The procedure is commonly performed through a Smith-Petersen incision. Trousdale RT, Ganz R: Periacetabular osteotomy, in Callaghan JJ, Rosenberg AG, Rubash HE (eds): The Adult Hip. Philadelphia, Pa, Lippincott-Raven, 1998, pp 789-802. Ganz R, Klaue K, Vinh TS, Mast JW: A new periacetabular osteotomy for the treatment of hip dysplasias: Technique and preliminary results. Clin Orthop 1988;232:26-36.

Morphologic and anatomic studies confirm the pedicle is smaller on the concave side of thoracic curves. The dura is also closer to the pedicle on the concave side of the curves. Liljenqvist U, Allkemper T, Hackenberg L, et al: Analysis of vertebral morphology in idiopathic scoliosis with use of magnetic resonance imaging and multiplanar reconstruction. J Bone Joint Surg Am 2002;84:359-368.

Glenoid dysplasia is an uncommon anomaly that usually has a benign course but may result in shoulder pain, arthritis, or multidirectional instability. Shoulder pain and instability often improve with shoulder strengthening exercises. Wirth MA, Lyons FR, Rockwood CA Jr: Hypoplasia of the glenoid: A review of sixteen patients. J Bone Joint Surg Am 1993;75:1175-1184.

Patients with Becker muscular dystrophy have an abnormality in dystrophin, but unlike patients with Duchenne muscular dystrophy, some dystrophin is present. As a result, the progression of muscle weakness is slower, with the diagnosis typically made after age 8 years. Similar to patients with Duchenne muscular dystrophy, patients with Becker muscular dystrophy have pseudohypertrophy of the calves, markedly increased creatine kinase levels, and X-linked transmission of the condition. In addition, these patients are more prone to cardiomyopathy; a condition that should be carefully evaluated if any surgery is required. Patients with spinal muscular atrophy also have proximal muscle weakness, but the onset of weakness occurs earlier in childhood. These patients also have absent deep tendon reflexes and fasciculations, but pseudohypertrophy is absent and creatine kinase levels are normal. Patients with Emery-Dreifuss dystrophy may have a similar clinical picture to Becker's muscular dystrophy, but pseudohypertrophy is absent and creatine kinase levels are only mildly elevated. In addition, neck extension, elbow flexion, and ankle equinus contractures develop at an early age. Limb girdle dystrophy is a group of progressive muscular dystrophies that is not associated with pseudohypertrophy or a significant elevation of creatine kinase levels. Guillain-Barre syndrome is a condition associated with results from postinfectious demyelination of the peripheral nerve. These patients have the acute onset of weakness, hypotonia, and areflexia; creatine kinase levels are normal. Sussman MD: Muscular dystrophy, in Fitzgerald RH, Kaufer H, Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1573-1583.

The patient has osteosarcoma. The radiograph suggests an aggressive primary tumor of bone, and the histology shows malignant cells surrounded by osteoid, classic for osteosarcoma. Ewing's sarcoma histologically consists of small round blue cells. Osteochondroma and periosteal chondroma occur in the shoulder but have a different histologic pattern and a less aggressive radiographic appearance. Chondrosarcomas rarely occur in children. Simon MA, Springfield DS, et al: Osteogenic Sarcoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 266.

The on-field evaluation and management of the seriously injured athlete requires advance preparation and planning. It is imperative that the health care team have a game plan in place and the proper equipment readily available. The initial step consists of stabilizing the head and neck by manually holding the head and neck in a neutral position. Then, in the following order, check for breathing, pulses, and level of consciousness. If the athlete is breathing, simply remove the mouth guard and maintain the airway. If the athlete is not breathing, the face mask must be removed and the chin strap left in place. An open airway must be established, followed by assisted breathing. CPR is only instituted when breathing and circulation are compromised. If the athlete is unconcious or has a suspected cervical spine injury, the helmet must not be removed until the athlete has been transported to an appropriate facility and the cervical spine has been completely evaluated. McSwain NE, Garnelli RL: Helmet removal from injured patients. Bull Am Coll Surg 1997;82:42-44. Vegso JJ, Lehman RC: Field evaluation and management of head and neck injuries. Clin Sports Med 1987;6:1-15.

Because the radiograph reveals an intermetatarsal angle of greater than 15 degrees and an incongruent metatarsophalangeal joint, the treatment of choice is a proximal first metatarsal osteotomy with distal soft-tissue realignment. A distal chevron procedure would not correct this degree of deformity. A Keller procedure is reserved for a less active elderly individual. Arthrodesis is appropriate for a patient with advanced arthritis of the metatarsophalangeal joint. The double osteotomy is reserved for the congruent metatarsophalangeal joint with hallux valgus. Coughlin MJ, Carlson RE: Treatment of hallux valgus with an increased distal metatarsal articular angle: Evaluation of double and triple first ray osteotomies. Foot Ankle Int 1999;20:762-770.

The central one third has been established as the watershed zone by angiographic studies, and has been borne out in clinical conditions involving the navicular, such as stress fractures and osteonecrosis. These findings account for the susceptibility to injury at this level. Nunley JA, Pfeffer GB, Sanders RW, et al (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 239-242.

Recovery of upper extremity motor function after a cerebrovascular accident follows a predictable pattern. The greatest amount of recovery is seen within the first 6 weeks. Return of function proceeds from proximal to distal. Shoulder flexion occurs first, followed by return of flexion to the elbow, wrist, and fingers. Return of forearm supination follows the return of finger flexion.

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.

The risk of intraoperative fracture in osteoporotic bone in patients with rheumatoid arthritis is significant. Fractures most often occur during humeral head dislocation and positioning for canal reaming. If the fracture occurs at the greater tuberosity, cerclage suture fixation of the tuberosity fracture with autogenous cancellous bone graft from the resected humeral head is the treatment of choice. Wright TW, Cofield RH: Humeral fractures after shoulder arthroplasty. J Bone Joint Surg Am 1995;77:1340-1346. Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 215-225.

Following a CVA and with the resumption of upright posture, downward subluxation of the glenohumeral joint may occur. Although usually painless, some patients may report pain secondary to stretching of the brachial plexus. This is the result of flaccid paralysis of the deltoid muscle, and it will persist until some motor tone or spasticity returns to the shoulder girdle musculature. Early sling support and range-of-motion exercises to prevent contracture will provide the best relief. Surgical procedures are not indicated. Braun RM, Botte MJ: Treatment of shoulder deformity in acquired spasticity. Clin Orthop 1999;368:54-65.

Although the imaging reveals generalized lumbar spondylosis and stenosis, in particular at L4-5, the MRI scan of the left hip clearly reveals a stress fracture of the femoral neck. Therefore, the treatment of choice is non-weight-bearing of the left lower extremity. During the evaluation of acute back pain, clinicians must include other possibilities within the differential diagnosis that may mimic mechanical axial back pain; thus, potential complications from a missed diagnosis can be avoided. Wong DA, Transfeldt E: Macnab's Backache, ed 4. Philadelphia, PA, Lippincott Williams and Wilkins, 2007, pp 339-361.

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.

Cutaneous sensation to the buttock is provided by the superior, middle, and inferior cluneal nerves. The superior cluneal nerves are the lateral branches of the dorsal rami of the upper three lumbar nerves and penetrate deep fascia just proximal to the iliac crest. They pass distally to the skin of the buttock and will be injured if the exposure extends more than 8 cm anterolateral to the posterior superior iliac spine. The lateral femoral cutaneous nerve can be injured in an anterior ilium bone graft. The superior gluteal nerve or even the sciatic nerve can be injured if bone is removed from the sciatic notch or dissection is not kept subperiosteal; however, the rate of injury is far less than cluneal nerve injury. The L5 and S1 nerve roots are anterior and can be injured if the inner table bone is harvested and the dissection is not kept subperiosteal or is too medial; however, the rate of injury still is far less than cluneal nerve injury. Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics: The Anatomic Approach. Philadelphia, PA, JB Lippincott, 1984, pp 295-297. Hollinshead WH: Textbook of Anatomy, ed 3. Hagerstown, MD, Harper and Row, 1974, p 379. Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, p 23.

The risk of infection in a 3B open tibia fracture is most directly related to the timing of the soft-tissue coverage and less related to the size or location of the wound. The wound VAC does not lower or raise the risk of infection in open fractures. It does appear to increase the window of time to obtain coverage without increasing the risk of infection. Additionally, the wound VAC may decrease the probability of needing free tissue coverage. Intramedullary nailing has not been shown to lower the risk of infection in 3B fractures. Godina M: Early microsurgical reconstruction of complex trauma of the extremities. Plast Reconstr Surg 1986;78:285-292. Dedmond BT, Kortesis B, Punger K, et al: The use of negative-pressure wound therapy (NPWT) in the temporary treatment of soft-tissue injuries associated with high-energy open tibia shaft fractures. J Orthop Trauma 2007;21:11-17.

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.

Congenital scoliosis in an infant warrants evaluation of the renal, cardiac, and neurologic systems because frequently there is concurrent pathology. Progression in this instance is possible but not certain; therefore, progression must be documented prior to any surgical intervention. Close observation with serial radiographs every 4 to 6 months is appropriate. All of the surgical options listed may be reasonable choices in the future, but cardiac evaluation is the most important issue at this time. Basu PS, Elsebaie H, Noordeen MH: Congenital spinal deformity: A comprehensive assessment at presentation. Spine 2002;27:2255-2259.

The saphenous nerve follows the saphenous vein, giving off the infrapatellar branch that crosses the knee anteriorly to supply the peripatellar skin. A longitudinal incision can interrupt the nerve, leaving the terminal distribution without sensation.

The most common mechanism of injury for turf toe is a hyperextension injury to the MTP joint. The foot is typically in a dorsiflexed position with the heel raised when an external force drives the MTP joint into further dorsiflexion. The joint capsule usually tears at the metatarsal neck because its attachment is weaker there than at the proximal phalanx. Some compression injuries to the dorsal articular surface of the metatarsal head can result from extension or hyperextension. Clanton TO, Ford JJ: Turf toe injury. Clin Sports Med 1994;13:731-741.

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

The anterior pin should be placed just above and lateral to the eyebrow at the site labeled A. At site B, the supraorbital nerve can be damaged. At site C, the supratrochlear nerve or the frontal sinus can be damaged. The site labeled D is over the temporalis muscle; in this location the temple bone is thin and there is the risk of perforation. Site E is above the equator of the forehead; at this location there is a risk that the halo ring will slip off the head altogether. 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 most serious injury associated with proximal tibial physeal fracture is vascular trauma. The popliteal artery is tethered by its major branches near the posterior surface of the proximal tibial epiphysis. During tibial physeal displacement, the popliteal artery is susceptible to injury. Injuries to the other structures are less common.

The patient has anterior interosseous nerve palsy. Initial management should consist of splinting followed by observation; surgical decompression may be required if there is no improvement in the functional deficit in 6 months. Anterior interosseous nerve palsy is classically described as an inability to flex the interphalangeal joint of the thumb because of flexor pollicis longus paralysis and a weakness or inability to flex the distal interphalangeal joint of the index finger because of weakness and/or paralysis of the flexor digitorum profundus to the index finger. There has been some controversy in the literature as to whether this represents a true peripheral compression neuropathy or neuritis. Recent recommendations have been to extend the period of observation from 3 to 6 months before surgical decompression, as most cases will resolve within 6 months. Miller-Breslow A, Terrono A, Millender LH: Nonoperative treatment of anterior interosseous nerve paralysis. J Hand Surg Am 1990;15:493-496.

Acetabular screws are inserted to supplement fixation. The acetabular component can be divided into four quadrants. Anatomic studies have shown that screws placed in the anterior superior and anterior inferior quadrants of the cup may injure the external iliac vein and obturator artery, respectively. Posterior superior and posterior inferior placement (in screws greater than 25 mm) may injure the sciatic nerve or the superior gluteal artery. The common iliac artery is proximal to the acetabulum and is at least risk for injury from acetabular screw placement.

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.

The radiographs show a halo-like sclerotic margin around the tibial stem and lucency under the baseplate. The bone scan shows markedly increased uptake under the tibial component, particularly on the medial side (not diffusely through the knee as seen with infection). These studies indicate lack of bone ingrowth fixation of the cementless porous-coated tibial component. The recent report of Fehring and associates has identified failure of ingrowth of a porous-coated implant as a dominant mode of early failure of total knee arthroplasties. Fehring TK, Odum S, Griffin WL, Mason B, Nadaud M: Early failures of total knee arthroplasty. Clin Orthop 2001;392:315-318.

The patient has an avulsion of the flexor digitorum profundus. Treatment should include surgical exploration and tendon reinsertion. This is not an avulsion of the flexor digitorum superficialis because the patient's deficiency is the inability to flex the distal interphalangeal joint, not the proximal interphalangeal joint. Surgical release of the anterior interosseous nerve is not indicated because the flexor digitorum profundus of the ring finger is innervated by the ulnar nerve. A median nerve contusion causes wrist pain and/or numbness and tingling in the median nerve distribution. Strickland JW: Flexor tendons: Acute injuries, in Green DP, Hotchkiss RN, Pederson WC (eds): Green's Operative Hand Surgery, ed 4. Philadelphia, PA, 1999, pp 1851-1897.

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.

Fractures of the hook of the hamate frequently are not identified in the acute phase. Because the fracture can be difficult to see on plain radiographs, the lack of findings can lead to a painful nonunion. A carpal tunnel view may show the fracture, but a CT scan will best detect the injury. Immobilization is the treatment of choice and will result in union in most patients unless the diagnosis is delayed. However, excision of the fragment may be necessary for patients who have nonunion, persistent pain, or ulnar nerve palsy. Carroll RE, Lakin JF: Fracture of the hook of the hamate: Acute treatment. J Trauma 1993;34:803-805.

A patient with an infected total hip arthroplasty may lack the symptoms of fever, chills, redness, or increased warmth typical of septic arthritis. Sensitivity for ESR and CRP ranges from 61% to 96%, and specificity ranges from 85% to 100%. Technetium Tc 99m bone scans are costly and time-consuming and will not differentiate between septic and aseptic loosening. Hip aspiration has a false-positive rate of up to 15%, although it may be useful in this patient to further complement the clinical picture if the ESR and CRP are elevated. The WBC count is rarely elevated in infected total hip arthroplasty. MRI is expensive and is not indicated for the diagnosis; however, it can aid in identifying intrapelvic extension of a periprosthetic abscess. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 455-492.

Ankle arthrodesis for posttraumatic ankle arthrosis provides reliable pain relief. However, the long-term sequela of joint arthrodesis is the development of arthrosis in the surrounding joints. Over time, following ankle arthrodesis, the ipsilateral hindfoot and midfoot joints show signs of joint space wear, and this may be symptomatic. With a stable ankle arthrodesis, progressive limb-length discrepancy or talar osteonecrosis is not expected. Ankle arthrodesis has not been definitively linked to ipsilateral knee arthritis or contralateral ankle arthritis. Coester LM, Saltzman CL, Leupold J, Pontarelli W: Long-term results following ankle arthrodesis for post-traumatic arthritis. J Bone Joint Surg Am 2001;83:219-228.

The most common side effect of an interscalene block is ipsilateral phrenic nerve blockade. The phrenic nerve arises chiefly from the fourth cervical ramus (with contributions from the third and fifth) and is the sole motor supply to the diaphragm. Phrenic nerve palsy usually is well tolerated in healthy patients but should be avoided in patients with limited pulmonary function (severe restrictive or obstructive lung disease, myasthenia gravis, or contralateral hemidiaphragmatic dysfunction). The incidence of ipsilateral phrenic nerve blockade afer interscalene block approaches 100%. Long T, Wass C, Burkle C: Perioperative interscalene blockade: An overview of its history and current clinical use. J Clin Anesthesia 2002;14;546-556.

The radiograph reveals the classic "bump" that is seen in patients with femoroacetabular impingement (FAI). Ganz and associates described two types of FAI. This patient has cam impingement, which describes a nonspherical femoral head being forced into the acetabulum during hip motion and resulting in labral and chondral injury. Hip arthroscopy and labral debridement is unlikely to control the symptoms because the underlying anatomic abnormality is often difficult to address with arthroscopy. The treatment involves surgical dislocation of the hip with preservation of the blood supply to the femoral head, removal of the asphericity on the femoral side (femoral osteoplasty), and removal of the acetabular rim (acetabular osteoplasty) if the latter is found to contribute to impingement. Ganz R, Gill TJ, Gautier E, et al: Surgical dislocation of the adult hip a technique with full access to the femoral head and acetabulum without the risk of avascular necrosis. J Bone Joint Surg Br 2001;83:1119-1124. Ganz R, Parvizi J, Beck M, et al: Femoroacetabular impingement: A cause for early osteoarthritis of the hip. Clin Orthop 2003;417:112-120.

Acceptable alignment in both bone forearm fractures is related to age and location. In children younger than age 9 years, angulations of 15 degrees and malrotation of 45 degrees are acceptable. In children older than age 9 years, acceptable alignment is 10 degrees of angulation and 30 degrees of malrotation. Bayonet apposition is acceptable provided that the angular and rotational reductions are held within these guidelines. A long arm cast provides better control of deforming forces than a short arm cast. Do TT, Strub WM, Foad SL, et al: Reduction versus remodeling in pediatric distal forearm fractures: A preliminary cost analysis. J Pediatr Orthop B 2003;12:109-115. Flynn JM: Pediatric forearm fractures: Decision making, surgical techniques, and complications. Instr Course Lect 2002;51:355-360. Ring D, Waters PM, Hotchkiss RN, et al: Pediatric floating elbow. J Pediatr Orthop 2001;21:456-459.

The dial or spherical osteotomy leaves the medial wall or teardrop in its original position and, as a result, is intra-articular. The other pelvic osteotomies (except Chiari) redirect the acetabulum, including the medial wall. The Chiari osteotomy improves coverage without redirecting the acetabulum within the pelvis, and it leaves the teardrop in the same place. Lack W, Windhager R, Kutschera HP, Engel A: Chiari pelvic osteotomy for osteoarthritis secondary to hip dysplasia: Indications and long-term results. J Bone Joint Surg Br 1991;73:229-234. Ganz R, Klaue K, Vinh TS, Mast JW: A new periacetabular osteotomy for the treatment of hip dysplasias: Technique and preliminary results. Clin Orthop 1988;232:26-36.

A farm injury is automatically considered a grade III (Gustillo classification) injury regardless of size, energy, or additional soft-tissue injury due to the likelihood of substantial contamination. Antibiotic recommendations for grade III injuries include a first- or second-generation cephalosporin with an aminoglycoside or fluoroquinolone within 3 hours of injury, with penicillin added for farm injuries. Okike K, Bhattacharyya T: Trends in the management of open fractures: A critical analysis. J Bone Joint Surg Am 2006;88:2739-2748.

Radiographs reveal malunion of a Monteggia fracture-dislocation. Dislocation of the posterior radial head is caused by the malunited ulnar fracture. The deformity includes shortening with an apex posterior angulation. In the acute setting, open reduction of the radial head rarely is necessary; however, in chronic dislocations, open reduction is required. Without ulnar osteotomy, recurrent radial head dislocation is likely.

The sagittal T1-weighted MRI scan is useful for interpreting the quality of muscle. The arrow is pointing to the teres minor. Goutallier D, Postel JM, Gleyze P, et al: Influence of cuff muscle fatty degeneration on anatomic and functional outcomes after simple suture of full-thickness tears. J Shoulder Elbow Surg 2003;12:550-554.