100 Orthopedic MCQs: Trauma, Spine & Pediatrics | Comprehensive ABOS Board Review

Follow-up examination at 6 months revealed no statistically significant differences in quadricep or hamstring strength when comparing surgical versus nonsurgical extremities isokinetically. Therefore, the selection of autogenous hamstring or patellar tendon for ACL reconstruction should not be based solely on the assumption of the graft tissue source altering the recovery of quadricep and/or hamstring strength. Carter TR, Edinger S: Isokinetic evaluation of anterior cruciate ligament reconstruction: Hamstring versus patellar tendon. Arthroscopy 1999;15:169-172 Howell SM, Taylor MA: Brace-free rehabilitation, with early return to activity, for knees reconstructed with a double-looped semitendinosus and gracilis graft. J Bone Joint Surg Am 1996;78:814-825.

With soft-tissue loss, local or free flap coverage may be necessary to treat exposed tendon and bone. However, a vacuum-assisted closure device is a good temporizing dressing. It prevents external contamination, reduces edema around the wound, increases oxygen tension in the wound, and promotes the formation of granulation tissue. The use of this negative pressure device has been described in both acute traumatic and in chronic wound scenarios. If sufficient granulation tissue forms, closure may be by split graft, avoiding a more complex coverage procedure. Immediate skin grafting over the exposed anterior tibial tendon and tibia would have a low likelihood of success. Dressing changes with sulfasalazine may be beneficial in a burn wound to assist with removal of skin slough; however, in a granulating wound, the material may be toxic to early epithelialization. Xenograft is a foreign body and should not be applied to an acute contaminated open wound. Historically, a cross-leg flap was a treatment alternative for lower extremity soft-tissue loss; however, its current applications are extremely limited. Webb LX: New techniques in wound management: Vacuum assisted wound closure. J Am Acad Orthop Surg 2002;10:303-311.

Atlas and associates, in the Maine Lumbar Spine Study, reported that overall, patients treated initially with surgery reported better outcomes. By 5 years, 19% of surgical patients had undergone at least one additional lumbar spine operation, and 16% of nonsurgical patients had opted for at least one lumbar spine operation. At the 5-year follow-up, 70% of patients initially treated surgically reported improvement in their predominant symptom (back or leg pain) versus 56% of those initially treated nonsurgically. They also noted that there was no difference in the proportion of patients receiving disability compensation at the 5-year follow-up.

Subscapularis tears can be associated with disruption of the transverse ligament supporting the biceps. The remaining aspects of the rotator cuff, superior labrum, and capsule can be intact with this injury. Petersson CJ: Spontaneous medial dislocation of the tendon of the long biceps brachii. Clin Orthop 1986;211:224-227.

The history, physical examination, laboratory, and radiographic findings are most consistent with an infectious process. When there are signs of neurologic compromise, surgery is generally recommended. This is an anterior process, and anterior column debridement is necessary, followed by stabilization. Anterior or posterior stabilization is a reasonable option, but posterior decompression alone is unlikely to adequately reverse the process and may lead to segmental kyphosis. Frymoyer JW, Wiesel SW (eds): The Adult and Pediatric Spine, ed 3. Philadelphia, PA, Lippincott Williams and Wilkins, 2003, pp 165-189.

The patient has an isthmic spondylolysis. The plain radiographs are normal, but the MRI scans show increased marrow edema and signal at the L5 pars interarticularis. Findings of bilateral hamstring tightness and increased pain with extension over flexion suggests spondylolysis. The MRI scans do not show any signs of the other conditions. Wiltse LL, Rothman SL: Spondylolisthesis: Classification, diagnosis and natural history. Sem Spine Surg 1993;5:264-280.

Tendons, cortical bone, ligaments, menisci, and fibrous tissue will show low signal intensity (SI) on both T1- and T2-weighted images. Fat-containing tissues, such as subcutaneous fat and bone marrow, will show high SI on T1-weighted images and low SI on T2-weighted images. Tissues with high water content, such as joint fluid, intervertebral disk, and edema, will show low SI on T1-weighted images and high SI on T2-weighted images. Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 65-70.

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 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.

The use of bisphosphonates has been recently associated with the development of osteonecrosis of the jaw. Length of exposure seems to be the most important risk factor for this complication. The type of bisphosphonate may play a role and previous dental procedures may be a precipitating factor. Bisphosphonates are a class of therapeutic agents originally designed to treat loss of bone density (ie, alendronate). The primary mechanism of action of these drugs is inhibition of osteoclastic activity, and it has been shown that these drugs are useful in diseases with propensities toward osseous metastases. In particular, they are effective in diseases in which there is clear upregulation of osteoclastic or osteolytic activity, such as breast cancer and multiple myeloma, and have developed into a mainstay of treatment for individuals with these diseases. Although shown to reduce skeletal events, there has been no improvement in patient survival. Bamias A, Kastritis E, Bamia C, et al: Osteonecrosis of the jaw in cancer after treatment with bisphosphonates: Incidence and risk factors. J Clin Oncol 2005;23:8580-8587. Thakkar SG, Isada C, Smith J, et al: Jaw complications associated with bisphosphonate use in patients with plasma cell dyscrasias. Med Oncol 2006;23:51-56.

The flexed knee and ankle mechanism of injury can result in a PCL and/or posterolateral corner injury. The examination reveals an isolated injury to the posterolateral corner (arcuate, popliteus, posterolateral capsule). This results in increased posterior translation and external rotation, as well as varus that is most notable at 30 degrees of flexion and decreases as the knee is further flexed to 90 degrees. Combined PCL and posterolateral corner injuries are characterized by increasing instability as the knee is flexed to 90 degrees from 30 degrees, while isolated PCL tears show the greatest degree of instability at 90 degrees of flexion. A rupture of the quadriceps tendon would not affect anterior or posterior stability, whereas an isolated rupture of the lateral collateral ligament, which is a rare injury, is characterized by varus instability at 30 degrees of knee flexion without posterior translation. Harner CD, Hoher J: Evaluation and treatment of posterior cruciate ligament injuries. Am J Sports Med 1998;26:471-482.

A prospective randomized study of patients with degenerative spondylolisthesis and spinal stenosis by Herkowitz and Kurz showed significantly improved clinical outcomes in patients who also received a lumbar arthrodesis. Patients with a laminectomy at an adjacent level do not have improved outcomes with an arthrodesis. Minimal lumbar scoliosis does not require arthrodesis. Arthrodesis is indicated in cases where there is removal of more than 50% of the facets bilaterally but not with an associated foraminal stenosis. Herkowitz HN, Kurz LT: Degenerative lumbar spondylolisthesis with spinal stenosis: A prospective study comparing decompression with decompression and intertransverse process arthrodesis. J Bone Joint Surg Am 1991;73:802-807.

The radiographs show displacement of the prosthesis, and there has been large amounts of bone resected to insert the implant. Arthrodesis is indicated with interposition bone graft to stabilize the joint and restore length to the first ray.

The radiographs show osteochondritis dissecans of the capitellum and a loose body in the anterior compartment. Arthroscopic removal is indicated because symptoms referable to the loose body are present. Baumgarten TE: Osteochondritis dissecans of the capitellum. Sports Med Arthroscopy Rev 1995;3:219-223.

Although the classic radiographic appearance of fibrous dysplasia is one of a central metaphyseal lesion with ground glass matrix, it is not unusual to see either a more radiodense-appearing lesion or a more peripheral location. The histologic finding of spicules of woven bone without osteoblastic rimming in a bland fibrous background is diagnostic of fibrous dysplasia. The imaging studies could be consistent with low-grade osteosarcoma, osteoblastoma, or osteomyelitis, but all have a very different histologic picture. Observation is indicated in the absence of symptoms, impending fracture, or deformity. Fibrous dysplasia most commonly occurs in the proximal femur. Huvos AG: Bone Tumors: Diagnosis, Treatment, and Prognosis. Philadelphia, PA, WB Saunders, 1991, pp 30-43.

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.

Kinematic analysis of both menisci demonstrates anterior movement with extension and posterior movement with flexion. The lateral meniscus has more mobility than the medial meniscus because of less soft-tissue attachments. Insall JN, Scott WN (eds): Surgery of the Knee, ed 3. New York, NY, Churchill Livingstone, 2001, vol 1, p 474. Thompson WO, Thaete FL, Fu FH, et al: Tibial meniscal dynamics using 3D reconstructions of MR images, in Proceedings of the Orthopaedic Research Society 1990;389.

The displaced talar neck fracture should be treated with open reduction and internal fixation using screws. Closed reduction and casting will not maintain position, and percutaneous pinning is not able to maintain reduction to allow union. External fixation and amputation are not necessary for this injury unless there is severe soft-tissue loss.

The key to this question is the fact that the patient initially lost flexion postoperatively and this relates to anterior placement of the femoral tunnel, thus capturing the knee. The bone plug seen on the radiograph is actually from the tibial tunnel, but this occurred as the patient forced flexion until failure of the ACL graft and pullout of the plug from the tunnel. Although it could be argued that better tibial fixation would have prevented this failure, poor placement of the femoral tunnel led to the failure of this ACL reconstruction. Fu FH, Bennett CH, Latterman C, et al: Current trends in anterior cruciate ligament reconstruction: Part 1. Biology and biomechanics of reconstruction. Am J Sports Med 1999;27:821-830.

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

A variety of methodologies have been used to decrease the need for homologous blood transfusions following THA. Some of the effective strategies include preoperative donation of autologous units, intraoperative salvage and recycling, preoperative injection of erythropoietin, and regional anesthesia. Cementless fixation and use of wound drains have been shown to increase the blood loss with THA. Huo MH, Paly WL, Keggi KJ: Effect of preoperative autologous blood donation and intraoperative and postoperative blood recovery on homologous blood transfusion requirement in cementless total hip replacement operation. J Am Coll Surg 1995;180:561-567. Bierbaum BE, Callaghan JJ, Galante JO, Rubash HE, Tooms RE, Welch RB: An analysis of blood management in patients having a total hip or knee arthroplasty. J Bone Joint Surg Am 1999;81:2-10.

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

In a study of 52 patients with infected total knee arthroplasties, Windsor and associates showed that the average leukocyte count was 8,300/mm3 and that aspirated knee fluid was positive in all patients except one. Knee radiographs can be unclear in showing infection, which may be present without radiographic signs of loosening. Technetium Tc 99m and gallium bone scans may not conclusively show the presence of infection, particularly in the first 3 years after knee arthroplasty. Windsor RE, Bono JV: Infected total knee replacements. J Am Acad Orthop Surg 1994;2:44-53.

Scapular body fractures in children are rare and are often associated with other injuries of the chest and thorax. Management is generally nonsurgical, unless the injury is open, and usually consists of support with a sling and gentle range-of-motion exercises to minimize shoulder stiffness. Green N, Swiontkowski M: Skeletal Trauma in Children, ed 2. Philadelphia, PA, WB Saunders, 1998, vol 3, pp 319-341.

The patient has a parosteal osteosarcoma of the distal femur. The findings of mild knee pain, radiographic evidence of a radiodense mass involving the parosseous space or surface of the distal femur, and histologic findings of a spindle cell lesion forming immature osteoid with little to no necrosis most likely suggest a parosteal osteosarcoma. The treatment of choice is surgical resection. Okada K, Frassica FJ, Sim FH, Beabout JW, Bond JR, Unni KK: Parosteal osteosarcoma: A clinicopathological study. J Bone Joint Surg Am 1994;76:366-378.

Scoliotic deformities in patients with NF1 are often dysplastic with short, angular curves. Posterior arthrodesis is made more difficult by the presence of kyphosis and of weak posterior elements caused by dural ectasia. Combined anterior and posterior spinal arthrodesis is generally preferred for progressive dysplastic curves to maximize deformity correction and to decrease the risk of pseudarthrosis. Anterior fusion may also prevent crankshaft phenomenon in young children. Brace treatment is not effective for large, rigid, or dysplastic curves. Kim HW, Weinstein SL: Spine update: The management of scoliosis in neurofibromatosis. Spine 1997;22:2770-2776.

MRI with gadolinium will best identify recurrent herniated nucleus pulposus or other root compression and distinguish scar from recurrent disk. CT is unable to distinguish scar from recurrent disk density, and the addition of myelogram dye can reveal compromise of the thecal sac but cannot distinguish the scar from recurrent disk as the source of compression. Although lateral flexion-extension radiographs may be important to rule out any instability, much of that information can be inferred from the associated disk and adjacent bony changes on MRI. Bone scan techniques may identify subtle stress fractures resulting from previous aggressive facet resection, but low back pain also would be expected. Mirowitz SA, Shady KL: Gadopentetate dimeglumine-enhanced MR imaging of the postoperative lumbar spine: Comparison of fat-suppressed and conventional T1-weighted images. Am J Roentgenol 1992;159:385-389.

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

The radiograph reveals a "bony mallet injury." As the distal phalanx is not volarly subluxated, extension splinting, similar to a classic mallet injury without bony involvement, is appropriate. If there is volar subluxation associated with a large bony fragment, surgical intervention is appropriate. Baratz ME, Schmidt CC, Hughes TB: Extensor tendon injuries, in Green DP, Hotchkiss RN, Pederson WC, et al (eds): Green's Operative Hand Surgery, ed 5. Philadelphia, PA, Elsevier, 2005, p 192.

This elbow fracture-dislocation involves a radial head fracture, coronoid fracture, and ulnohumeral dislocation (terrible triad). Several algorithms exist for treatment; surgical treatment is indicated. The treatment should address the radial head. Studies have shown replacement to be superior to repair in comminuted fractures. The coronoid may be addressed in unstable cases at the time of radial head excision and replacement. Lateral ligamentous repair is carried out during closure of the lateral elbow capsule. Medial ligamentous repair also may be undertaken but usually in concert with bony repair. Hinged external fixation remains an option when instability exists following bony and soft-tissue repair. Acute ulnar nerve transposition is rarely indicated. Ring D, Jupiter JB, Zilberfarb J: Posterior dislocation of the elbow with fractures of the radial head and coronoid. J Bone Joint Surg Am 2002;84:547-551.

Flexion contractures are the most common complication of elbow dislocations. About 15% of patients lose more than 30 degrees of flexion. The risk of contracture is proportional to the duration of immobilization. Elbows should be moved within the first few days after reduction. The splinting is for comfort and protection only while the pain subsides. Mehlhoff TL, Noble PC, Bennett JB, Tullos HS: Simple dislocation of the elbow in the adult: Results after closed treatment. J Bone Joint Surg Am 1988;70:244-249. Linscheid RL, O'Driscoll SW: Elbow dislocations, in Morrey BF (ed): The Elbow and Its Disorders, ed 2. Philadelphia, PA, WB Saunders, 1993, pp 441-452. O'Driscoll SW, Jupiter JB, King GJ, Hotchkiss RN, Morrey BF: The unstable elbow. Instr Course Lect 2001;50:89-102.

In a longitudinal study of 18 patients with spastic diplegia over a period of 32 months, three-dimensional gait analysis revealed a deterioration of gait stability with increases in double support time and decreases in single support time. Kinematic data also identified a loss of excursion about the knee, ankle, and pelvis. Interestingly, the static examination of the children showed a decrease in the popliteal angle over time. The authors concluded that ambulatory ability tends to worsen over time in children with spastic diplegia.

Surgical decompression and stabilization have been shown to be the most effective means of improving neurologic function. Decompression is most reliably done from the side of the compression, which is anterior in this patient. Harrington KD: Metastatic tumors of the spine: Diagnosis and treatment. J Am Acad Orthop Surg 1993;1:76-86.

The radiograph reveals disruption of the symphysis pubis and a displaced left sacral fracture. A posterior injury with displacement of greater than 1 cm is unstable, and a sacral fracture is particularly unstable. Surgical stabilization is required for these unstable anterior and posterior injuries. External fixation provides little stability to an unstable posterior pelvic injury. Reduction and internal fixation of the symphysis pubis and sacral fracture will provide the most stable pelvis with the least resultant deformity and allow patient mobilization. Tile M: Management of pelvic ring injuries, in Tile M, Helfet DL, Kellam JF (eds): Fractures of the Pelvis and Acetabulum, ed 3. Philadelphia, PA, Lippincott Williams & Wilkins, 2003, pp 168-202.

The omohyoid muscle crosses the surgical field from inferior lateral to anterior superior traveling from the scapula to the hyoid bone and may need to be transected. The posterior digastric crosses the field as well but higher near C3-4. The other muscles run longitudinally. Chang U, Lee MC, Kim DH: Anterior approach to the midcervical spine, in Kim DH, Henn JS, Vaccaro AR, et al (eds): Surgical Anatomy and Techniques to the Spine. Philadelphia, PA, Saunders Elsevier, 2006, pp 45-56.

The MRI scan shows a far lateral disk herniation. With the L4-5 disk, a far lateral herniation abuts the left L4 nerve root. The findings would be consistent with those of a left L4 radiculopathy and would include pain or a sensory deficit on the anteromedial aspect of the knee, diminished patellar tendon reflex, and quadriceps weakness, perhaps making it difficult to walk up and down stairs. Fardin DF, Garfin SR (eds): Orthopaedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, p 329.

Ceramic bearings, made of alumina, have the lowest in vivo wear rates of any bearing combination, 0.5 to 2.5 Mm per component per year. Laboratory wear rates for metal-on-metal are lower than those for metal-on-polyethylene bearings, ranging from 2.5 to 5.0 Mm per year. Titanium used for bearing surfaces has a high failure rate because of a poor resistance to wear and notch sensitivity. Wear rates for ceramic-on-polyethylene bearings have varied, ranging from 0 to 150 Mm. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 47-53.

Overhead athletes are prone to a number of problems involving the shoulder. Pitchers and volleyball players are susceptible to posterior superior labral tears and internal impingement. These patients will have posterior superior shoulder pain, a positive relocation sign, and a positive active compression test. Occasionally, these posterior superior labral tears are associated with a spinoglenoid cyst as seen in the MRI scan. These cysts cause compression of the suprascapular nerve which manifests primarily as weakness of the infraspinatus, resulting in weakness of external rotation. Romeo AA, Rotenberg DD, Bach BR Jr: Suprascapular neuropathy. J Am Acad Orthop Surg 1999;7:358-367.

Shufflebarger and others have reported that the placement of anterior interbody structural support at the lumbosacral junction increases the overall construct stiffness and reduces the strain on posterior instrumentation, thereby reducing the risk of screw pull-out or fracture. The stiffness of the posterior instrumentation actually increases, whereas the actual strength of the instrumentation remains the same. Actual strain measured at an adjacent intervertebral disk to a fusion construct is expected to increase. Shufflebarger HL: Moss-Miami spinal instrumentation system: Methods of fixation of the spondylopelvic junction, in Margulies JI, Floman Y, Farcy JPC, et al (eds): Lumbosacral and Spinal Pelvic Fixation. Philadelphia, PA, Lippincott-Raven, 1996, pp 381-393. Cunningham BW: A biomechanical approach to posterior spinal instrumentation: principles and applications, in DeWald RL (ed): Spinal Deformities: A Comprehensive Text. New York, NY, Thieme, 2003, pp 588-600.

The radiograph reveals developmental dysplasia of both hips. The patient has classic anterolateral undercoverage of the femoral head on the right side as demonstrated by a high acetabular index (measured at 27 degrees). Anterior undercoverage can be determined by drawing the marking for the anterior wall that fails to overlap the femoral head in this patient. Currently in North America, the most accepted surgical management for symptomatic dysplasia of the hip with good joint space is a Bernese (Ganz) periacetabular osteotomy. Surgical dislocation of the hip and femoroacetabular osteoplasty may be considered for patients with symptomatic femoroacetabular impingement of the hip. Ganz R, Klaue K, Vinh TS, et al: A new periacetabular osteotomy for the treatment of hip dysplasias: Technique and preliminary results. Clin Orthop 1988;232:26-36.

The first branch of the lateral plantar nerve is susceptible to entrapment beneath the deep fascia of the adductor hallucis muscle adjacent to the calcaneal attachment of the plantar fascia. This can be a cause of chronic heel pain. Additionally, the nerve is vulnerable to injury by a blind dissection in releasing the plantar fascia. The dorsal cutaneous branch of the superficial peroneal nerve supplies sensation to the dorsum of the foot. The medial calcaneal branch of the posterior tibial nerve lies in the subcutaneous tissues and innervates the skin of the heel. It is vulnerable to injury from skin incisions on the medial side of the heel. The lateral branch of the medial plantar nerve forms the second and third common digital nerves. Entrapment of the proper medial plantar nerve can occur at the master knot of Henry. This is well distal to the calcaneal attachment of the plantar fascia, and the pain usually radiates more distally in the arch, separate from heel pain. The communicating branch of the fourth common digital nerve crosses to the third common digital nerve. Therefore, the third common digital nerve receives supply from both the lateral and medial plantar nerves. This dual supply has been implicated in the increased incidence of digital neuroma of the third common digital nerve. Bordelon RL: Heel pain, in Mann RA, Coughlin MJ (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, CV Mosby, 1993, pp 837-857. Mann RA, Baxter DE: Diseases of the nerves, in Mann RA, Coughlin MJ (eds): Surgery of the Foot and Ankle, ed 6. St Louis, MO, CV Mosby, 1993, pp 543-574.

Rheumatoid arthritis is sometimes associated with radiographic evidence of instability of the cervical spine. In a study by Grauer and associates, radiographs of the cervical spine of patients with rheumatoid arthritis who had undergone total joint arthroplasty over a 5-year period were retrospectively reviewed. Nearly one half of the patients had radiographic evidence of cervical instability on the basis of traditional measurements. While radiographic evidence of cervical instability was not infrequent in this population of patients who underwent total joint arthroplasty for rheumatoid arthritis, radiographic predictors of paralysis were much less common. MRI prior to surgery may also be a consideration if the radiographic appearance of the rotator cuff alters the consideration of surgical treatment. In a series of patients undergoing prosthetic arthroplasty for a variety of shoulder disorders, the presence of a rotator cuff tear has been shown to be associated with a less favorable outcome. Most often, the presence of a rotator cuff tear was associated with a diagnosis of rheumatoid or other inflammatory arthritis and the tears were large and generally irreparable. Some case series demonstrated a higher prevalence of loosening of the glenoid component in patients with a large rotator cuff tear associated with superior migration of the humeral head. However, obtaining an MRI scan of the shoulder is not considered the best response since failure to determine cervical instability may result in anesthetic death. Whereas MRI may be helpful in planning reconstruction, it would be a less important priority. Grauer JN, Tingstad EM, Rand N, et al: Predictors of paralysis in the rheumatoid cervical spine in patients undergoing total joint arthroplasty. J Bone Joint Surg Am 2004;86:1420-1424.

The primary action of the posterior tibialis tendon is inversion of the foot; secondarily, it plantar flexes the ankle. The anterior tibialis tendon also inverts the foot and only partially antagonizes the posterior tibialis tendon. The primary action of the peroneus longus is plantar flexion of the first ray. It secondarily everts the posterior tibialis tendon. The action of the flexor digitorum longus tendon is synergistic with the posterior tibialis tendon. The primary action of the peroneus brevis tendon is eversion; therefore, it is the primary antagonist of the posterior tibialis tendon. Sarrafian SK: Anatomy of the Foot and Ankle: Descriptive, Topographic, Functional, ed 2. Philadelphia, PA, JB Lippincott, 1993, pp 550-551.

Patients with brachial neuritis or Parsonage-Turner syndrome usually report the sudden onset of intense pain that subsides in 1 to 2 weeks, followed by weakness for a period of up to 1 year in the muscle that is supplied by the involved nerve. Calcific tendinitis usually can be diagnosed radiographically, with calcium deposits seen in the rotator cuff. Bursitis and rotator cuff tendinosis usually are seen after an increase in activity, and both decrease with rest and medication. Glenohumeral arthritis is a slow, progressive problem that results in a loss of range of motion. Misamore GW, Lehman DE: Parsonage-Turner syndrome (acute brachial neuritis). J Bone Joint Surg Am 1996;78:1405-1408.

There has been a recent increase in the use of outcome instruments to document and measure effects of treatment of medical conditions, including shoulder disorders. The most important feature of an instrument is whether it actually measures what it purports to measure; this is defined as its validity. Leggin BG, Iannotti JP: Shoulder outcome measurement, in Iannotti JP, Williams GR (eds): Disorders of the Shoulder: Diagnosis and Management. Philadelphia, PA, Lippincott Williams and Wilkins, 1999, p 1027.

Unwitnessed spiral fractures should raise the possibility of child abuse, especially prior to walking age. With nonaccidental trauma being considered in the differential diagnosis, a skeletal survey is indicated to determine if there are other fractures in various stages of healing. Kempe CH, Silverman FN, Steele BF, et al: The battered-child syndrome. JAMA 1962;181:17-24.

The patient has degeneration of an adjacent segment with resultant kyphosis and stenosis. Because he is healthy, has responded well to previous surgery, and has a potentially correctable lesion, he is not a good candidate for an end-stage failed back procedure such as a morphine pump. The stenosis is exacerbated by the deformity; therefore, a simple decompression will contribute to instability. Because of the kyphosis and the patient's relatively young age, the treatment of choice is restoration of sagittal alignment and posterior decompression.

The radiographs show an oblique periprosthetic distal femoral fracture. Of the options listed, open reduction and internal fixation is the most appropriate surgical option because a well-fixed, posterior stabilized closed box femoral component is present. Nonsurgical methods are not favored because of the highly displaced, unstable fracture pattern and prolonged immobility. Revision with a stemmed component is an option but would sacrifice more bone stock in this younger patient. Moran MC, Brick GW, Sledge CB, et al: Supracondylar femoral fracture following total knee arthroplasty. Clin Orthop 1996;324:196-209. Raab GE, Davis CM III: Early healing with locked condylar plating of periprosthetic fractures around the knee. J Arthroplasty 2005;20:984-989.

The reconstruction requires additional resection of the distal femur to allow increased extension while maintaining the current flexion gap tension. Resecting more proximal tibia or decreasing the tibial polyethylene thickness will decrease flexion tension as well as extension tension. Adding posterior femoral augments and using a larger femoral component will increase flexion tension. Ayers DC, Dennis DA, Johanson NA, et al: Common complications of total knee arthroplasty. J Bone Joint Surg Am 1997;79:278-311.

Urbaniak and Harvey reported donor site morbidity following free vascularized fibular graft in 198 consecutive patients. At a 5-year follow-up, they reported overall complications in 24% of the patients. The most common complication was a sensory deficit (11.8%), followed by motor weakness (2.7%), flexor hallucis longus contracture (2%), and deep venous thrombosis (less than 1%).

The treatment of choice for closed diaphyseal femoral fractures in adults is reamed intramedullary nailing with static interlocking. Reaming allows placement of a larger, stronger implant and offers better healing rates than unreamed nailing. Static interlocking ensures that there is no loss of reduction because of underappreciated fracture lines or comminution. Brumback RJ, Virkus WW: Intramedullary nailing of the femur: Reamed versus nonreamed. J Am Acad Orthop Surg 2000;8:83-90.

The findings are typical for an osteochondroma. It is found as an outgrowth of bone and cartilage from those bones that arise from enchondral ossification. It may be flat, verrucous, or with a long stalk and cauliflower-like cap. Osteochondromas can become symptomatic secondary to irritation of the adjacent musculature. They cease to proliferate when epiphyseal growth ceases.

Greater tuberosity anterior fractures associated with anterior glenohumeral dislocations respond very well to closed methods in the majority of patients. Closed reduction of the glenohumeral joint often anatomically reduces the greater tuberosity into its cancellous bed, without the need for open fixation or cuff repair. Once closed reduction of the joint is performed, tuberosity displacement and joint articulation should be evaluated radiographically with AP and scapular lateral views as well as an axillary view. The axillary view will not only definitively show the joint articulation but also demonstrate posterior displacement of the greater tuberosity missed on the AP and lateral views. If no or minimal (5 mm) displacement is found, then nonsurgical management consisting of a sling and gentle passive range-of-motion exercises can be instituted. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.

Measurements of compartment pressures in patients with tibial fractures and compartment syndrome reveal that the highest tissue pressures are recorded at the level of the fracture or within 5 cm of the fracture. Tissue pressures show a statistically significant decrease when they are recorded at increasing distances proximal and distal to the site of the highest pressure recorded. To reliably determine the location of the highest tissue pressure in patients with tibial fractures, measurements should be obtained, at a minimum, in both the anterior and deep posterior compartments at the level of the fracture, as well as at locations proximal and distal. The highest tissue pressure recorded should serve as a basis for determining the need for fasciotomy. Heckman MM, Whitesides TE Jr, Grewe SR, Rooks MD: Compartment pressure in association with closed tibial fractures: The relationship between tissue pressure, compartment, and the distance from the site of the fracture. J Bone Joint Surg Am 1994;76:1285-1292.

Removal of both sesamoids is associated with a high incidence of postoperative hallux valgus and cock-up deformity of the great toe because of weakening of the flexor hallucis brevis tendon. The sesamoids lie within these tendons and require meticulous repair following excision. Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 17-25.

A Jones fracture occurs at the metaphyseal-diaphyseal junction of the fifth metatarsal. It is often an acute fracture in conjunction with a chronic stress-related injury. It requires either a short leg cast with strict non-weight-bearing or surgical fixation. In the high performance athlete, the need for rapid return to sport activity usually requires surgical intervention, most commonly with an intramedullary screw. Brodsky JW, Krause JO: Stress fractures of the foot and ankle, in Delee JC, Drez D (eds): Orthopaedic Sports Medicine, ed 2. Philadelphia, PA, Saunders, 2003, vol 2, pp 2391-2409.

With a severe articular injury to the calcaneus, the ability to achieve satisfactory results with open reduction and internal fixation diminishes. An arthrodesis is often needed to allow a person who works as a laborer to return to work. Recent literature suggests that this can be successfully performed primarily, improving the odds of an earlier return to the labor force at 1 year. Huefner T, Thermann H, Geerling J, Pape HC, Pohlemann T: Primary subtalar arthrodesis of calcaneal fractures. Foot Ankle Int 2001;22:9-14. Coughlin MJ: Calcaneal fractures in the industrial patient. Foot Ankle Int 2000;21:896-905.

The technique of intramedullary nailing with titanium elastic nails is based on the concept of balanced forces across the fracture site with two equally sized nails. Implantation of the largest sized nails possible, with two equally sized nails, maximizes the stiffness at the fracture site, thereby optimizing fracture alignment and stability. Impacting the nails into the medullary canal can impact the fixation by minimizing distal purchase of the nail at the cortical insertion site. Closed reduction commonly permits bony reduction and passage of the nails; open reduction is reserved for inability to align the fracture. Luhmann SJ, Schootman M, Schoenecker PL, et al: Complications of titanium elastic nails for pediatric femur fractures. J Pediatr Orthop 2003;23:443-447. Lascombes P, Haumont T, Journeau P: Use and abuse of flexible intramedullary nailing in children and adolescents. J Pediatr Orthop 2006;26:827-834.

Because the man is only recently removed from his injury and is judged capable of returning to work with some restrictions, the term that best describes his work status is temporary partial disability.

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

The MRI scans show Modic changes in the L4-L5 vertebral bodies due to spondylosis. There is no increased fluid signal or enhancement in the L4-L5 disk to suggest infection or any other pathologic process. Therefore, the patient's pain should be treated with a course of physical therapy and rehabilitation. There is no infection; therefore, IV antibiotics and debridement are not indicated. Similarly, a pseudomeningocele is not present. A revision diskectomy is useful for recurrent radiculopathy but would not be helpful for degenerative low back pain. Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 319-329.

In the immediate postoperative period following repair of an acute rotator cuff tear, passive forward elevation and external rotation should be performed within the safe zone determined at surgery. Early active range of motion (prior to tendon healing), internal rotation behind the back, and resistive exercises increase the risk of rupture of the repair. Iannotti JP: Full-thickness rotator cuff tear: Factors affecting surgical outcome. J Am Acad Orthop Surg 1994;2:87-95.

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

Cotler and associates reported on the use of awake skeletal traction to reduce facet fracture-dislocations in 24 patients. Seventeen patients required more than 50 pounds of traction (the "traditional" limit) to achieve reduction. More than 100 pounds of traction was safely used in one-third of the patients in this study. A cadaver study has supported the safe use of traction with weights in excess of 100 pounds. Cotler JM, Herbison GJ, Nasuti JF, et al: Closed reduction of traumatic cervical spine dislocation using traction weights up to 140 pounds. Spine 1993;18:386-390.

The radiographs show a displaced ankle fracture with widening of the syndesmosis. Open reduction and internal fixation is indicated with fixation of the mortise with syndesmotic screws. Wuest TK: Injuries to the distal lower extremity syndesmosis. J Am Acad Orthop Surg 1997;5:172-181.

Throwing athletes with symptomatic internal rotation deficits often benefit from an intensive posterior capsular stretching program. Patients that fail to respond to nonsurgical management may benefit from an arthroscopic posterior capsular release. Wilk KE, Meister K, Andrews JR: Current concepts in rehabilitation of the overhead throwing athlete. Am J Sports Med 2002;30:136-151.

The motorized shaver is adjacent to the acetabular labrum, which is torn. The femoral head and acetabulum are normal in appearance. Neither the fat pad nor a loose body is identified.

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.

Athletic pubalgia refers to a distinct syndrome of lower abdominal and adductor pain that is mostly commonly seen in high performance male athletes. This condition must be distinguished from others such as painful inflammation of the symphysis pubis, referred to as osteitis pubis. Symptoms attributable to the iliopsoas tendon are most commonly associated with snapping of the tendon. Stress fracture of the pubic ramus may cause symptoms in this area, but it is usually confirmed by imaging studies. Neurapraxia of the pudendal nerve is associated with pressure from the seat in cycling sports and also as a complication associated with traction during surgical procedures. Meyers WC, Foley DP, Garrett WE, Lohnes JH, Mandlebaum BR: Management of severe lower abdominal or inguinal pain in high-performance athletes: PAIN (Performing Athletes with Abdominal or Inguinal Neuromuscular Pain Study Group). Am J Sports Med 2000;28:2-8.

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.

There are a number of important technical details in performing a biopsy. Incisions should always be longitudinal in the extremity. Good hemostasis is important in avoiding contamination from hematoma. The approach should avoid neurovascular structures, and go through a single muscle belly when possible. Although a frozen section should be obtained to ensure adequate viable tissue has been obtained, definitive diagnosis is not necessary at the time of the frozen section. Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 197-215.

Premature consolidation is a complication that is unique to gradual bone lengthening after corticotomy. Causes include excessive latency period, inadequate distraction rate, exuberant bone formation, patient compliance problems, and mechanical failure of the distraction apparatus. The femur and fibula are most commonly involved. This patient did not have an incomplete corticotomy, as initial distraction occurred before the distraction device was noted to seize up. The radiographs show bowing of the Ilizarov wires and mature regenerate bone, both suggestive of premature consolidation. No wire breakage or joint subluxation is seen on the radiographs. Treatment for premature consolidation includes continuing distraction until the consolidation bridge ruptures, or additional surgery may include closed rotational osteoclasis or repeat corticotomy. Paley D: Problems, obstacles and complications of limb lengthening, in Maiocchi AB, Aronson J (eds): Operative Principles of Ilizarov. Baltimore, MD, Williams & Wilkins, 1991, p 360.

The presence of drainage 3 weeks after surgery is a sign of wound infection. This infection most likely involves deep tissues until proven otherwise. Oral or IV antibiotics, in the absence of debridement, are not sufficient. Removal of the hardware would lead to rapid progression of the scoliosis in a spine that has been surgically destabilized by removal of the facet joints. The appropriate treatment is debridement with wound culture, IV antibiotics, and retention of hardware. The wound should be closed over drains. Theiss SM, Lonstein JE, Winter RB: Wound infections in reconstructive spine surgery. Orthop Clin North Am 1996;27:105-110.

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

A positive lift-off test and increased passive external rotation are diagnostic of a subscapularis tear or detachment. Although a similar injury could produce anterior instability, this will test the integrity of the subscapularis. A locked dislocation has limited passive movement. A ruptured biceps tendon will most likely produce ecchymosis and findings similar to supraspinatus trauma. Internal impingement is not associated with subscapularis weakness. Gerber C, Krushell RJ: Isolated rupture of the tendon of the subscapularis muscle: Clinical features in 16 cases. J Bone Joint Surg Br 1991;73:389-394.

The patient's history, examination, and radiographs are classic for locked posterior dislocation of the glenohumeral joint. Posterior dislocation of the shoulder remains the most commonly missed dislocation of a major joint. Up to 80% are missed on initial presentation. The primary cause for failure to accurately diagnose this injury is inadequate radiographic evaluation. The typical presentation is a shoulder locked in internal rotation with loss of abduction. An axillary view not only will make the definitive diagnosis but will help assess the size of the articular surface defect and help plan treatment. This view can be done expediently as part of every trauma series. The AP view is suspicious for a posteriorly dislocated humerus with loss of the humeral neck profile, a vacant glenoid sign, and an anterior humeral head compression fracture (reverse Hill-Sachs lesion). Hawkins RJ, Neer CS II, Pianta RM, Mendoza FX: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18. Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosement, IL, American Academy of Orthopaedic Surgeons, 1997, pp 181-189.

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

The patient has a displaced scapular spine fracture that has resulted in shoulder weakness from a poor deltoid lever arm. The downward tilt may lead to subacromial impingement and rotator cuff dysfunction. Open reduction and internal fixation would best allow normal deltoid and shoulder function. Bone stimulators and abduction bracing may lead to healing but in a malunited position. Arthroscopic acromioplasty and fragment excision should be avoided. Ogawa K, Naniwa T: Fractures of the acromion and the lateral scapular spine. J Shoulder Elbow Surg 1997;6:544-548.

The results of TKA for patients with a prior UTO are reported to be slightly suboptimal. The major problems are patella baja, difficulty in exposure, and instability. Most of the patients exhibit some degree of instability prior to TKA, and ligamentous balancing may be difficult. Ligamentous structures are at risk of rupture during the difficult exposure. The problem of ligamentous balancing is exacerbated by the change in the joint slope that can occur after UTO. Parvizi J, Hanssen AD, Spangehl MJ: Total knee arthroplasty following proximal tibial osteotomy: Risk factors for failure. J Bone Joint Surg Am 2004;86:474-479.

Typically, posterior spinal fusion to the pelvis is recommended for patients with spinal muscular atrophy and advanced scoliosis. Examination for lower extremity muscle contractures is important because the contractures may interfere with good sitting balance. Anterior release and fusion usually are not advised. Diaphragmatic pacing is not indicated because diaphragm function usually is not affected. Patients with spinal muscular atrophy usually are not ambulatory or only marginally ambulatory at the time of scoliosis surgery; therefore, gait analysis usually is not relevant. While a muscle biopsy may have a role in the diagnosis of this disorder, it plays no subsequent role in determining life expectancy or the value of spinal surgery. Daher YH, Lonstein JE, Winter RB, Bradford DS: Spinal surgery in spinal muscular atrophy. J Pediatr Orthop 1985;5:391-395.

Plastic deformation of viscoelastic tissues represents deformation of the soft tissues to the point of failure. The lining up of collagen fibers would be in the "toe region" of the curve, which, in the case of the FSU, would be mainly in the neutral zone. Elastin is a minor contributor to the composition of the ligaments and would be protected by the stiffer collagen fibers. The transition between flexion and extension occurs in the neutral zone, and reversible elongation occurs in the elastic zone. Fardon DF, Garfin SR, Abitbol J, et al (eds): Orthopaedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 15-23.

In examining a traditional Muslim woman, a male physician should have another woman present, and the patient's husband, if possible. Only the affected limb or area needing examination should be exposed.

Brodsky and associates reviewed 34 cases of cervical pseudarthrosis after anterior fusion. Seventeen were treated with revision anterior fusion and 17 with posterior foraminotomy and fusion. Good results were seen in 75% of patients who underwent revision anterior surgery, but better results (94%) were seen with posterior surgery, including foraminotomy and stabilization. Tribus and associates reported treatment of 16 patients with pseudarthrosis using revision anterior debridement of the fibrous tissue and fusion with autograft and plates. There was improvement of the neck in 75% of the patients, nonunion in 19%, continued weakness in 28%, and dysphagia in 5%. Farey and associates reported on 19 patients treated with posterior foraminotomy, stabilization, and fusion with a fusion rate of 100%, resolution of arm pain in 94%, resolution of weakness in 100%, and resolution of neck pain in 75%. It would appear that posterior foraminotomy is more effective for relieving arm pain and neurologic deficits associated with pseudarthrosis. Posterior fusion has the most reliable rate of arthrodesis in this setting. Dysphagia is reported in some patients undergoing more extensive anterior dissections required for applying plates. A neck brace is unlikely to aid in healing of pseudarthrosis in a patient who underwent surgery 8 months ago. A neck brace would be most effective within the first 3 months if a delayed union is identified. Brodsky AE, Khalil MA, Sassard WR, Neuman BP: Repair of symptomatic pseudarthrosis of anterior cervical fusion: Posterior versus anterior repair. Spine 1992;17:1137-1143. Tribus CB, Corteen DP, Zdeblick TA: The efficacy of anterior cervical plating in the management of symptomatic pseudarthrosis of the cervical spine. Spine 1999;24:860-864.

Casali and associates provided a recent review of the treatment options for chordomas. These tumors are not radiosensitive; however, modern intensity modulated radiosurgery techniques may be of value. The combination of surgery and radiotherapy compared to surgery alone results in the same disease-free survival time. Complete surgical resection of the chondroma with clean margins offers the best survival; however, its location may make total removal impossible. Thus subtotal resection followed by radiotherapy results in better survival despite the tumor's lack of radiosensitivity.

In a review of 190 anterior cervical fusions, Hilibrand and associates reported that only 20 of 40 patients who smoked had solid fusion at all levels, whereas 64 of 91 nonsmokers had solid fusions at all levels when treated with multilevel interbody technique (Smith-Robinson). When fused with strut grafts, 14 of 15 smokers and 41 of 44 nonsmokers had solid fusions with a fusion rate of 93% in the same series. Multilevel allografts have a lower fusion rate than autografts, and diskectomy without fusion has an increased rate of residual neck pain. Hilibrand AS, Fye MA, Emery SE, et al: Impact of smoking on the outcome of anterior cervical arthrodesis with interbody or strut-grafting. J Bone Joint Surg Am 2001;83:668-673.

In a report of more than 70 hips treated by surgical dislocation, iatrogenic osteonecrosis failed to develop in any of the hips.

Forty percent of osteoblastomas occur in the spine, and they can become large and locally aggressive lesions. They generally occur in the posterior elements but can occur in the ribs and transverse processes. Microscopic analysis of the lesion will reveal hyperchromatic osteoblasts separated by incompletely mineralized bars of bone. Recommended treatment is en bloc excision. Fibrous dysplasia, giant cell tumor, and hemangioma can have similar radiographic appearances; therefore, biopsy may be required to differentiate them from more aggressive lesions. Osteochondromas are characterized by an osteocartilaginous growth arising from the cortex. Bridwell KH, Ogilvie JW: Primary tumors of the spine, in Bridwell KH, DeWald RL (eds): The Textbook of Spinal Surgery. Philadelphia, PA, JB Lippincott, 1991, vol 2, pp 1143-1174.

Recent medical literature supports the use of bisphosphonates as the treatment of choice for active Paget's disease.

Necrotizing fasciitis is an aggressive and rapidly spreading soft-tissue infection, usually caused by group A beta-hemolytic Streptococcus pyogenes. Presentation is typical of a rapidly ascending cellulitis, recalcitrant to antibiotic treatment. Differentiation between cellulitis and impetigo is difficult, and success depends on a high level of suspicion. The skin and subcutaneous tissues are affected, with sparing of the muscles. Septic shock and multi-organ system failure can be fatal. Treatment is aggressive surgical debridement with broad-spectrum antibiotics. Repeat irrigation and debridement may be necessary. Hyperbaric oxygen studies have shown inconsistent results. Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 199-205.

Isometric quadriceps contraction between 15 and 30 degrees of flexion creates significant strain in the ACL and potential damage to the reconstructed graft. Isolated quadriceps contraction with knee flexion of greater than 60 degrees, hamstring contraction at any angle of knee flexion, and active knee motion between 35 and 90 degrees of flexion create substantially less strain in the properly implanted ACL graft. Beynnon BD, Gleming BC, Johnson RL, Nichols CE, Renstrom PA, Pope MH: Anterior cruciate ligament strain behavior during rehabilitation exercises in vivo. Am J Sports Med 1995;23:24-34.

Of the levels given, T5 has the most narrow pedicle in anatomic studies. One study in patients with scoliosis did note that T7 on the concave side was more narrow than T5, but T7 is not listed here as a possible answer. O'Brien MF, Lenke LG, Mardjetko S, et al: Pedicle morphology in thoracic adolescent idiopathic scoliosis: Is pedicle fixation an anatomically viable technique? Spine 2000;25:2285-2293.

Femoral neck fracture nonunion is a challenging problem for orthopaedic surgeons. Vertical fractures are more prone to nonunion due to shear stress rather than compressive forces across the fracture site. Several authors have suggested these fractures are more common in young adults due to injury type and bone composition. It is widely regarded that an effort should be made to salvage the femoral head if vascularity remains. The most common method to treat this complication is valgus intertrochanteric osteotomy of the femur. This functionally makes a vertical fracture more horizontal, converting shear into compressive forces. It also helps correct the varus position of the fracture nonunion. Hartford JM, Patel A, Powell J: Intertrochanteric osteotomy using a dynamic hip screw for femoral neck nonunion. J Orthop Trauma 2005;19:329-333.

Symptoms of activity-related low back pain, physical findings of pain with extension, lateral bending, and resuming an upright position, and relative hamstring tightness are consistent with spondylolysis. While the initial diagnostic work-up should include plain radiographs of the lumbosacral spine, the findings may be negative because it can take weeks or months for the characteristic changes to become apparent. SPECT has been a useful adjunct in the diagnosis of spondylolysis when plain radiographs are negative. Since the patient's pain is activity related and she is otherwise healthy, evaluation for infection is not indicated. Because the neurologic examination is normal, electromyography, nerve conduction velocity studies, and MRI are not indicated. CT can be used in those instances in which SPECT and bone scans are negative. Ciullo JV, Jackson DW: Pars interarticularis stress reaction, spondylolysis, and spondylolisthesis in gymnasts. Clin Sports Med 1985;4:95-110. Collier BD, Johnson RP, Carrera GF, et al: Painful spondylolysis or spondylolisthesis studied by radiography and single photon emission computed tomography. Radiology 1985;154:207-211. Jackson DW, Wiltse LL, Cirincione RT: Spondylolysis in the female gymnast. Clin Orthop 1976;117:68-73.

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 patient has end-stage arthritis of the elbow with advanced joint destruction. At this point, nonsurgical management is unlikely to provide much relief of symptoms. Arthroscopic procedures can provide relief, but it is likely to be incomplete and unpredictable. The most reliable surgical option is total elbow arthroplasty. Currently, semiconstrained components are generally preferred because constrained components have been associated with a high rate of early prosthetic loosening. Little CP, Graham AJ, Karatzas G, et al: Outcomes of total elbow arthroplasty for rheumatoid arthritis: Comparative study of three implants. J Bone Joint Surg Am 2005;87:2439-2448.

Children have a much greater capacity to heal soft-tissue injuries than adults. Most crush or avulsion fingertip amputations in children, particularly those younger than age 2 years, can be treated with serial dressing changes, even with bone exposed. Das SK, Brown HG: Management of lost finger tips in children. Hand 1978;10:16-27.

Pin track infections and sensory injuries are among the most common complications of external fixation for distal radius fractures. The proximal pins of most distal radius external fixators are placed in the "bare area" of the distal radius, about four finger-breadths above the radial styloid. This corresponds to the area where the dorsal sensory branch of the radial nerve penetrates the fascia dorsal to the brachioradialis tendon to become a subcutaneous structure. Injury to the superficial radial nerve may produce painful dysesthesias and neuromas.

The most commonly used portals are the anterolateral, anteromedial, and posterolateral portals. They have been shown to be the safest areas for portal placement, allowing no penetration of neurovascular structures. All the other portals involve placing another structure at risk. The anterocentral portal is close to the deep peroneal nerve and anterior tibular artery. The trans-Achilles portal is not recommended because of its limited utility and potential to injure the Achilles tendon. The posteromedial portal is too close to the posterotibial artery and nerve, the flexor hallucis longus and flexor digitorum longus tendons, and the branches of the calcaneal nerve. Stetson WB, Ferkel RD: Ankle arthroscopy: I. Technique and complications. J Am Acad Orthop Surg 1996;4:17-23.

The patient is a young laborer with osteoarthritis. Initial treatment should begin with nonsurgical management that may include anti-inflammatory drugs, cortisone injections, and physical therapy to diminish pain and improve motion. The other choices may eventually be necessary but should only follow a course of nonsurgical management. Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 257-266.

The extracellular matrix consists of water, proteoglycans, and collagen. Water makes up the majority (approximately 65% to 80%) of wet weight; 95% of the collage is type II with much smaller amounts of other collagens, including types IV, VI, IX, X, and XI. The exact functions of these other collagens are unknown, but they are believed to be important in matrix attachment and stabilization of the diameter of collagen fibrils. 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 444-445.