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

The radiograph shows myositis ossificans within the quadriceps muscle. This condition occurs as a complication of muscle injury. Initial treatment should include rest, ice, compression, and elevation. While gentle active range of motion is encouraged in the functional recovery from this injury, passive stretching is contraindicated as it can enhance hemorrhage and accentuate the development of myositis ossificans. Ultrasound is similarly contraindicated because it can enhance the development of myositis ossificans and has no proven efficacy in this patient; electrical stimulation also has no proven benefits. Massage is contraindicated in the initial management of this injury because of its influence on increasing local blood flow. Anderson JE (ed): Grant's Atlas of Anatomy. Baltimore, MD, Williams & Wilkins, 1978, pp 4.39-4.49. Brumet ME, Hontas RB: The thigh, in DeLee JC, Drez D Jr (eds): Orthopaedic Sports Medicine. Philadelphia, PA, WB Saunders, 1994, pp 1086-1112. Antao NA: Myositis of the hip in a professional soccer player: A case report. Am J Sports Med 1988;16:82-83.

The coupled action of the rotator cuff prevents superior migration and controls anterior and posterior translation by depressing the humeral head. Poppen NK, Walker PS: Normal and abnormal motion of the shoulder. J Bone Joint Surg Am 1976;58:195-201.

The MRI scans show the typical findings of a torn discoid lateral meniscus. The average transverse diameter of the lateral meniscus is 11 or 12 mm. A discoid lateral meniscus is suggested when three or more contiguous 5-mm sagittal sections on the MRI scan show continuity of the menicus between the anterior and posterior horns, or when two adjacent peripheral sagittal 5-mm sections show equal meniscal height. Normally the black "bow tie" would be seen on two contiguous sagittal sections. The presence of a discoid meniscus can be further confirmed if coronal views reveal increased width. Jordan MR: Lateral meniscal variants: Evaluation and treatment. J Am Acad Orthop Surg 1996;4:191-200.

The patient has a cyclops lesion. This is a nodule of fibroproliferative tissue that originates from either drilling debris from the tibial tunnel or remnants of the ACL stump; more rarely it is the result of broken graft fibers. The treatment of choice is excision of the nodule and, if needed, additional notchplasty. Marked improvements in function and symptoms have been noted after removal of the extension block and resumption of a rehabilitation program. Delince P, Krallis P, Descamps PY, et al: Different aspects of the cyclops lesion following anterior cruciate ligament reconstruction: A multifactorial etiopathogenesis. Arthroscopy 1998;14:869-876.

The major blood supply to the cruciate ligaments arises from the ligamentous branches of the middle genicular artery. Few terminal branches of the inferior genicular artery contribute to the blood supply. The synovial plexus and sheath covering the cruciate ligaments are also supplied by branches of the middle genicular artery. The blood supply to the cruciate ligaments is predominately of soft-tissue origin. There is no significant osseous vascular contribution to the ligaments. Arnoczky SP: Anatomy of the anterior cruciate ligament. Clin Orthop 1983;172:19-25.

Ample evidence supports an increased rate of degenerative arthritis in the ACL-deficient knee. Several variables play a role in the development of the arthritis, but the integrity of the meniscus has been shown to be the single most important factor. O'Brien WR: Degenerative arthritis of the knee following anterior cruciate ligament injury: Role of the meniscus. Sports Med Arthroscopy Rev 1993;1:114-118. Fetto JF, Marshall JL: The natural history and diagnosis of anterior cruciate ligament insufficiency. Clin Orthop 1980;147:29-38.

The history and radiographs indicate a Lisfranc fracture-dislocation of the foot. The radiographs show the classic "fleck sign," which is an avulsion of the Lisfranc ligament from the base of the second metatarsal. Most authors recommend open reduction and internal fixation of this injury. Closed reduction can be attempted, but anatomic reduction is unlikely because of the interposed bone fragments and soft tissues. Standard radiographs are not reliable in identifying 1 to 2 mm of subluxation of the tarsometatarsal joint. The tarsometatarsal joint has a poor tolerance to even mild subluxation, and the resulting decrease in joint contact area increases the likelihood of posttraumatic arthritis. Open reduction with the joint visible allows more anatomic reduction and internal fixation of larger osteochondral fragments or excision of smaller interposed fragments. Bellabarba C, Sanders R: Dislocations of the foot, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, vol 2, pp 1539-1558.

Deep freezing is the simplest and most widely used method of ligament allograft storage. All cells in the tissue are destroyed with the freezing. However, for this reason, it is not a preferred storage method for menisci or cartilage allografts. Although this method may enhance success because it removes potential antigens located on the cells, it cannot guarantee elimination of HIV transmission. The advantage of cryopreservation storage is that a significant number of cells will survive the process, a factor important in meniscal allograft survival after implantation. No deleterious effects are noted clinically because of the acellularity of the tissue. Shelton WR, Treacy SH, Dukes AD, Bomboy AL: Use of allografts in knee reconstruction: I. Basic science aspects and current status. J Am Acad Orthop Surg 1998;6:165-168.

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

The patient has Kienbock's disease (osteonecrosis of the lunate), which presents with boggy synovitis of the wrist, decreased range of motion, and often normal radiographs. The patient's radiographs reveal small fragments from the lunate, with increased density in the lunate body. While a traumatic event may precede the patient's pain, often an insidious increase in pain is found. Repetitive trauma has been suggested as a possible cause. This disease process is classically associated with an ulnar-negative variant. An MRI scan, revealing a low-intensity signal in the lunate, is the best diagnostic tool for early Kienbock's disease. Green DP, Hotchkiss RN, Pederson WC: Green's Operative Hand Surgery, ed 4. Philadelphia, PA, Churchill Livingstone, 1999, pp 837-848.

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

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.

The valgus stress at the elbow caused by throwing strains the medial collateral ligament. The medial epicondyle, on which the ligament inserts, is the last ossification center to fuse to the distal humerus, and acute avulsion of the medial epicondyle can occur in adolescents. If the elbow is allowed to heal in a displaced position, valgus instability and loss of elbow extension may result. Valgus instability is especially problematic for the throwing athlete. Surgical treatment with rigid internal fixation is the treatment of choice for displaced medial epicondyle avulsion fractures. Valgus instability is prevented, and the rigid fixation allows for early range of motion. Case SL, Hennrikus WL: Surgical treatment of displaced medial epicondyle fractures in adolescent athletes. Am J Sports Med 1997;25:682-686.

During the late acceleration phase of throwing, the triceps forcibly contracts, extending the elbow as the ball is released. Normally, this force is absorbed by the anterior capsule and the brachialis and biceps muscles. However, if the ulnar collateral ligament is insufficient, the elbow will be in a subluxated position during extension and cause impaction of the olecranon and the olecranon fossa posteromedially. Over time, osteophyte formation is likely to occur. Conway JE, Jobe FW, Glousman RE, Pink M: Medial instability of the elbow in throwing athletes: Treatment by repair or reconstruction of the ulnar collateral ligament. J Bone Joint Surg Am 1992;74:67-83.

Hypertrophic cardiomyopathy is the leading cause of sudden cardiac death in athletes, accounting for 40% of reported cases. Most athletes have no previous symptoms, and sudden death may be the first clinical manifestation. The prevalence of hypertrophic cardiomyopathy in the general population is 1 in 500, with a mortality rate of 2% to 4% in young adults. Athletes with active myocarditis should not engage in sports for up to 6 months, and although they may be at risk for the development of chronic cardiomyopathy, it is rarely a cause of sudden cardiac death. Mitral valve prolapse with an accompanying systolic murmur is common in the general population, but infrequently a cause of sudden cardiac death. Weakening of the aortic wall associated with Marfan syndrome can result in abrupt rupture of the aorta. This accounts for 3% of sudden cardiac deaths in young athletes. Marfan syndrome usually can be detected on preparticipation screenings by its skeletal and ocular manifestations. Atherosclerotic coronary artery disease is the most common cause of sudden cardiac death in older athletes, accounting for 75% of reported cases. However, it is much less common in the young competitive athlete. Burke AP, Farb A, Virmani R, Goodin J, Smialek JE: Sports-related and non-sports-related sudden cardiac death in young adults. Am Heart J 1991;121:568-575.

Slipped capital femoral epiphysis is the most common pathology involving the hip in adolescents. While patients with acute slips may report severe pain and are unable to ambulate, those with chronic slips often have pain during ambulation, a limp, and increased external rotation of the hip. While 60% of the patients specifically report hip pain, the remainder have pain in the thigh or knee. The initial diagnostic study of choice is AP and frog-lateral radiographs of the pelvis; bilateral involvement is frequently seen. Boyer DW, Mickelson MR, Ponseti IV: Slipped capital femoral epiphysis: Long-term follow-up study of one hundred and twenty-one patients. J Bone Joint Surg Am 1981;63:85-95.

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.

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

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.

The hallmark for RSD or SMP is the presence of pain that is out of proportion to that expected for the degree of the injury. SMP often extends well beyond the involved area and is present in a nonanatomic distribution. The pain is frequently described as a burning sensation, with extreme sensitivity to light touch. Joint stiffness can be present but is a nonspecific finding. There may be cold intolerance, but this is not a cardinal symptom. Sweating actually may be increased. Osteopenia, if present, is a late finding. Lindenfeld TN, Bach BR Jr, Wojtys EM: Reflex sympathetic dystrophy and pain dysfunction in the lower extremity. Instr Course Lect 1997;46:261-268.

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

While many low-demand patients with injuries to the ulnar collateral ligament can be treated nonsurgically, Jobe and associates described two situations in which ulnar collateral ligament reconstruction is indicated: (1) an acute complete rupture in a competitive athlete who uses the upper extremities extensively and who wishes to remain active; and (2) chronic pain or instability that does not improve after at least 3 months of nonsurgical management. Rarely is direct surgical repair of the ligament possible or able to withstand the valgus stresses applied to the elbow. Most authors recommend surgical reconstruction of the ulnar collateral ligament using a palmaris longus, plantaris, or fourth toe extensor tendon from the fourth autograft. Andrews JR, Jelsma RD, Joyce ME, et al: Open surgical procedures for injuries to the elbow in throwers. Oper Tech Sports Med 1994;4:109-133. Jobe FW, Kvitne RS: Elbow instability in the athlete. Instr Course Lect 1991;40:17-23.

The patient has iliac apophysitis. The radiographic findings are easily overlooked but usually reveal slight asymmetric widening of the iliac crest apophysis. The apophysis is the most vulnerable structure, as it is three to five times weaker than the tendon. This is not an epiphyseal site, and injury to the muscle or the tendinous insertion to bone (enthesis) is unlikely. Clancy WG Jr, Foltz AS: Iliac apophysitis and stress fractures in adolescent runners. Am J Sports Med 1976;4:214-218. Waters PM, Millis MB: Hip and pelvic injuries in the young athlete, in Stanitski CL, DeLee JC, Drez D Jr (eds): Pediatric and Adolescent Sports Medicine. Philadelphia, PA, WB Saunders, 1994, pp 279-293. Lombardo SJ, Retting AC, Kerlan RK: Radiographic abnormalities of the iliac apophysis in adolescent athletes. J Bone Joint Surg Am 1983;65:444-446.

The radiograph shows calcific deposits within the substance of the supraspinatus tendon. Patients with this condition are prone to recurrent bouts of acute inflammation in the shoulder. While the response to cortisone injection is often dramatic, repeated injections are not recommended because of injury to the collagen fibers. Good results have been obtained with arthroscopic evacuation of the calcium deposits. In one study, the addition of a subacromial decompression did not improve the results. Jerosch J, Strauss JM, Schmiel S: Arthroscopic treatment of calcific tendinitis of the shoulder. J Shoulder Elbow Surg 1998;7:30-37.

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.