AAOS Sports Medicine MCQs (Set 1): Knee, Shoulder & Ankle Injuries | Board Review

Throwing athletes, particularly pitchers, have a high incidence of shoulder pain. Recent evidence suggests that posteroinferior capsular tightness and scapular dyskinesis may play a substantial role in the pathologic cascade, culminating in the development of articular surface rotator cuff tears and tearing of the posterosuperior labrum. These patients have posterosuperior shoulder pain primarily. Furthermore, these athletes are susceptible to a muscular fatigue syndrome, the SICK (Scapular malposition, Inferior medial border prominence, Coracoid pain and malposition, and dysKinesis of scapular movement) scapula syndrome. This patient has an internal rotation deficit and tenderness over the coracoid. The internal rotation deficit is addressed by stretching the posterior capsule. The tenderness over the coracoid has been attributed to a contracture of the pectoralis minor tendon secondary to scapular malposition. The initial phase of the rehabilitation regimen is directed at stretching the posterior capsule and pectoralis minor tendon. Burkhart SS, Morgan CD, Kibler WB: The disabled throwing shoulder: Spectrum of pathology. Part III. Arthroscopy 2003;19:641-661.

The radiograph shows posttraumatic tibiofibular synostosis. This condition typically follows an eversion (high) ankle sprain that results in disruption of the interosseous membrane. Ossification usually develops within 6 to 12 months after the injury. Return to sports is possible despite the lack of normal ankle dorsiflexion and mobility between the tibia and fibula. Surgical excision is reserved for persistent pain that fails to respond to nonsurgical management once the ossification is "cold" on bone scintigraphy. Whiteside LA, Reynolds FC, Ellsasser JC: Tibiofibular synostosis and recurrent ankle sprains in high performance athletes. Am J Sports Med 1978;6:204-208. Henry JH, Andersen AJ, Cothren CC: Tibiofibular synostosis in professional basketball players. Am J Sports Med 1993;21:619-622.

TFCC tears are common in athletes. As the athlete braces for a fall, the wrist is most commonly in an extended position and the forearm is pronated. Cohen MS: Ligamentous injuries of the wrist in the athlete. Clin Sports Med 1998;17:533-552.

The cross-sectional area of a muscle determines to a great extent the force generated by the muscle. The force of a muscle contraction is controlled by the amount of myofibrils that contract; the greater the amount of contracting myofibrils, the greater the force of contraction. Fiber types have less to do with the force of contraction and more to do with the duration and speed of contraction. Muscle length affects contraction force through the Blix curve. The morphology of a muscle can affect the cross-sectional area by varying the angle of the fibers in relation to the force vector. Conditioning mostly affects duration and fatigability. Buckwalter JA, Mow VC, Ratcliffe A: Restoration of injured or degenerated articular cartilage. J Am Acad Orthop Surg 1994;2:192-201.

PVNS is a rare inflammatory granulomatous condition of unknown etiology, and causes proliferation of the synovium of joints, tendon sheaths, or bursa. The disorder occurs most commonly in the third and fourth decades but can occur at any age. MRI provides excellent delineation of the synovial disease. Characteristic features of PVNS on MRI include the presence of intra-articular nodular masses of low signal intensity on T1- and T2-weighted images and proton density-weighted images. Synovial biopsy should be performed if there is any doubt of the diagnosis. Total synovectomy (open or arthroscopic) is required for the diffuse form, although recurrence is common. Rheumatoid arthritis and synovial chondromatosis are not typically associated with hemorrhagic effusions. De Ponti A, Sansone V, Malchere M: Result of arthroscopic treatment of pigmented villonodular synovitis of the knee. Arthroscopy 2003;19:602-607. Chin KR, Barr SJ, Winalski C, et al: Treatment of advanced primary and recurrent diffuse pigmented villonodular synovitis of the knee. J Bone Joint Surg Am 2002;84:2192-2202.

The patient has entrapment of the superficial peroneal nerve against its fascial opening in the distal leg. It is typically exacerbated by passive or active plantar flexion and inversion of the foot, which leads to traction of the nerve as it exits this opening. Treatment involves release of the fascial opening to reduce this traction phenomenon. Closure of the defect will only aggravate the condition and potentially result in an exertional compartment syndrome. A four-compartment fasciotomy is only indicated for an established compartment syndrome of the leg. Styf J: Diagnosis of exercise-induced pain in the anterior aspect of the lower leg. Am J Sports Med 1988;16:165-169. Sridhara CR, Izzo KL: Terminal sensory branches of the superficial peroneal nerve: An entrapment syndrome. Arch Phys Med Rehabil 1985;66:789-791.

The patient has a locked knee that cannot be fully extended. This is most likely the result of the mechanical block of a bucket-handle tear that has flipped into the notch. Also, the pain may be so severe that the muscle spasm prevents the knee from straightening out. When the patient is anesthetized, the muscle spasm relaxes and the meniscus can be reduced out of the notch. Arthroscopy is the treatment of choice. A meniscal repair is usually possible in large bucket-handle tears because the meniscus is torn in the red-red zone where most of the vascular supply is located. If the handle portion is badly frayed or damaged, a partial meniscectomy should be performed. The classic finding on MRI is a "double PCL sign." This is due to the flipped portion of the meniscus in the notch. Critchley IJ, Bracey DJ: The acutely locked knee: Is manipulation worthwhile? Injury 1985;16:281-283.

Capsular exposure for an inside-out lateral meniscal repair is performed by developing the interval between the iliotibial band and biceps tendon. Posterior retraction of the biceps tendon exposes the lateral head of the gastrocnemius. Posterior retraction of the gastrocnemius provides access to the posterolateral capsule. Miller DB Jr: Arthroscopic meniscus repair. Am J Sports Med 1988;16:315-320.

The muscle transfer procedure most commonly performed for trapezius paralysis is the Eden-Lange procedure. Trapezius paralysis in this patient is secondary to iatrogenic injury to the spinal accessory nerve during lymph node biopsy. In this procedure, the levator scapulae and rhomboid minor and major muscles are transferred laterally. Pectoralis transfer to the inferior border of the scapula is used as a dynamic transfer for serratus anterior winging. Kuhn JE, Plancher KD, Hawkins RJ: Scapular winging. J Am Acad Orthop Surg 1995;3:319-325. Langenskiold A, Ryoppy S: Treatment of paralysis of the trapezius muscle by Eden-Lange operation. Acta Orthop Scand 1973;44:383-388.

Tooth avulsions can occur in contact or collision sports. An avulsed tooth is a medical emergency. The likelihood of survival of the tooth depends on the length of time that the tooth is out of the socket and the degree to which the periodontal ligament is damaged. The tooth should be handled only by the crown end and not the root end. It can be rinsed of debris with water or normal saline solution. The tooth should not be brushed or cleaned otherwise. During transport, the tooth must be kept moist. An avulsed tooth can be transported in whole milk, saliva, sterile saline solution, or commercially available kits with physiologic buffer solutions. The tooth and the athlete should be transported to the dentist for reinsertion as soon as possible and preferably within an hour. Krasner P: Management of sports-related tooth displacements and avulsions. Dent Clin North Am 2000;44:111-135. Sullivan JA, Anderson SJ (eds): Care of the Young Athlete. Rosemont IL, American Academy of Orthopaedic Surgeons, Elk Grove Village, IL, American Academy of Pediatrics, 2000, p 190.

Commotio cordis is a rare but catastrophic condition that is caused by blunt chest trauma. It results in cardiac fibrillation and is universally fatal unless immediate defibrillation is performed. Although case reports of successful use of the chest thump maneuver exist, the best method of treatment is cardiac defibrillation. IV fluids, epinephrine, and albuterol inhalers are used to treat dehydration, anaphylactic shock, and bronchospasm respectively, and are not effective in the treatment of commotio cordis. McCrory P: Commotio cordis. Br J Sports Med 2002;36:236-237.

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

The radiographs reveal chondrocalcinosis of the menisci. This is caused by calcium pyrophosphate crystals, which are weakly positive birefringent rhomboid-shaped crystals. Frequently, this condition is asymptomatic; however, routine abdominal surgery may cause precipitation of these crystals and pain. Gout, which is caused by strongly negative birefringent needle-shaped sodium urate crystals, is not associated with chondrocalcinosis and is rare in younger women. Gross blood is uncommon without trauma. Infection is not likely in a healthy patient who underwent uncomplicated surgery. Fisseler-Eckhoff A, Muller KM: Arthroscopy and chondrocalcinosis. Arthroscopy 1992;8:98-104.

In the early 1990s, a transition was made from a two-incision ACL reconstruction to a single-incision ACL reconstruction, and there was concern over divergence of the femoral screws. It was shown radiographically that approximately 5% of the time, divergence of the screw was greater than 15 degrees from the bone plug. In a bovine model, there was significant loss of pull-out strength with an increase in divergence from 15 degrees to 30 degrees. Therefore, attempts should be made to minimize divergence to 15 degrees or less. Lemos MJ, Jackson DW, Lee TO, et al: Assessment of initial fixation of endoscopic interference femoral screws with divergent and parallel placement. Arthroscopy 1995;11:37-41.

The patient has snapping hip syndrome of the internal type, which is more common in ballet dancers. It is caused by the iliopsoas tendon gliding over the iliopectineal line or the femoral head. The diagnosis usually can be made by the history and physical examination. Snapping is reproduced by hip flexion and extension or flexion with external rotation and abduction. Conventional and dynamic ultrasonography will confirm the snapping structure. Radiographs occasionally show calcifications near the lesser trochanter. MRI can be used to rule out other diagnoses that can simulate snapping hip. Gruen GS, Scioscia TN, Lowenstein JE: The surgical treatment of internal snapping hip. Am J Sports Med 2002;30:607-613.

The posterior circumflex artery provides blood supply only to the posterior portion of the greater tuberosity and a small posteroinferior portion of the humeral head. The humeral head is supplied primarily by the anterolateral ascending branch of the anterior circumflex artery; the terminal branch of this artery is termed the arcuate artery. Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 267-274.

Several studies have looked at the effects of knee bracing, and it appears to be effective in prophylactically decreasing the incidence of medial collateral ligament sprains. Najibi and Albright reported that although evidence is not conclusive, bracing appears to help decrease the incidence of medial collateral ligament injuries. Albright and associates showed similar findings. Prophylactic knee braces have been associated with an increased incidence of ankle injuries. Albright JP, Powell JW, Smith W, et al: Medial collateral ligament knee sprains in college football: Effectiveness of preventive braces. Am J Sports Med 1994;22:12-18.

The patient has a tension pneumothorax. This is a life-threatening emergency where air is trapped between the pleura and the lung, which prevents expansion of the lung. This causes hypoxia and cardiopulmonary compromise. The first line of treatment is to place a needle into the second intercostal space in the midclavicular line. The athlete should then be transported to the emergency department for chest tube placement. The athlete cannot return to play, and resuscitation is not necessary because he has not gone into cardiopulmonary arrest. Amaral JF: Thoracoabdominal injuries in the athlete. Clin Sports Med 1997;16:739-753.

The use of anabolic steroids causes a decrease in high-density lipoprotein levels but has no effect on low-density lipoprotein levels. An abnormally low high-density lipoprotein level should alert the physician to the possibility of steroid use in an athlete. Hartgens F, Rietjens G, Keizer HA, et al: Effects of androgenic-anabolic steroids on apolipoproteins and lipoprotein (a). Br J Sports Med 2004;38:253-259.

The incidence of injury associated with horseback rising is estimated to be one per 350 riding hours to one per 1,000 riding hours. Of these injuries, approximately 15% to 27% are severe enough to warrant hospital admission. Significant and serious injuries in equestrian activities are associated with recreational riders and those not wearing a helmet. Head and spine injuries are more common in recreational and nonhelmeted riders. Extremity injuries are more common in professional and helmeted riders. Professional riders are less likely to be admitted to the hospital than recreational riders, and are about half as likely to be disabled at 6 months after injury as recreational riders. Lim J, Puttaswamy V, Gizzi M, et al: Pattern of equestrian injuries presenting to a Sydney teaching hospital. ANZ J Surg 2003;73:567-571.

The radiographs reveal osteoarthritis and proximal humeral head migration. Integrity of the rotator cuff must be questioned based on these radiographic changes. The status of the rotator cuff is the most influential factor affecting postoperative function in shoulder hemiarthroplasty. The coracoacromial ligament provides a barrier to humeral head proximal migration in the face of a rotator cuff tear. The radiographs do not indicate significant humeral head or glenoid erosion. Acromioclavicular arthritis is often asymptomatic. Iannotti JP, Norris TR: Influence of preoperative factors on outcome of shoulder arthroplasty for glenohumeral osteoarthritis. J Bone Joint Surg Am 2003;85:251-258.

All of the answers are possible complications of meniscal repair. There are large volumes of literature evaluating the results of meniscal repair, both for the all-inside technique, as well as the inside-out technique. Failure rates are similar. Intra-articular synovitis occurs with absorbable sutures and absorbable implants. Peroneal nerve injuries are more common with the lateral-sided repairs. Saphenous nerve injuries are more common with medial-sided tears. Because of the incision required and the technique of tying over soft tissue, the risk of a saphenous nerve injury is greater with an inside-out technique than with an all-inside technique. Farng E, Sherman O: Meniscal repair devices: A clinical and biomechanical literature review. Arthroscopy 2004;20:273-286.

The CT scan shows a stress fracture of the olecranon. This injury is the result of repetitive abutment of the olecranon into the olecranon fossa, traction from triceps activity during the deceleration phase of the throwing motion, and impaction of the medial olecranon onto the olecranon fossa from valgus forces. Fractures may be either transverse or oblique in orientation. Initial treatment consists of rest and temporary splinting. Electrical bone stimulation may also be considered. Open fixation with a large compression screw is recommended when nonsurgical management has failed to provide relief. Ahmad CS, ElAttrache NS: Valgus extension overload syndrome and stress injury of the olecranon. Clin Sports Med 2004;23:665-676.

The spleen is the most common organ injured in the abdomen as the result of blunt trauma. It is also the most common cause of death because of an abdominal injury. The liver is the second most commonly injured organ. Injury to the other organs is rare. The diagnosis can be made with CT. Treatment ranges from observation to splenectomy, depending on the severity of injury. Green GA: Gastrointestinal disorders in the athlete. Clin Sports Med 1992;11:453-470.

The loss of consciousness indicates a grade 2 concussion, which necessitates a 4-week period out of sport. The last week prior to return must be symptom-free and the athlete should not have symptoms in practice. Cantu RC: Return to play guidelines after a head injury. Clin Sports Med 1998;17:45-60.