5. Sports Medicine MCQs

The MRI scan shows a bone bruise of the lateral femoral condyle and lateral tibial plateau. This injury pattern is commonly associated with anterior cruciate ligament (ACL) rupture and an abnormal pivot shift test result. Treatment of an ACL tear in a high-demand athlete should consist of ligament reconstruction. In this patient, surgery should be delayed until she regains full range of motion to minimize risk for arthrofibrosis after surgery. Recent analysis has shown that the noncontact mechanism is more consistent with anterior translation, affecting both the medial and lateral compartments. The bone bruise in the lateral femoral condyle occurs more anterior than that of the medial femoral condyle, suggesting that internal rotation has occurred. The external rotation recurvatum test assesses for posterolateral corner injury, and a positive quadriceps active test is consistent with posterior cruciate ligament rupture. An abnormal patellar apprehension test result is suggestive of patellar instability. Nonsurgical treatment is unlikely to result in sufficient stability if this patient returns to sports at her preinjury level of activity. Primary ACL repair is associated with high failure rates. Although the precise mechanism of injury varies, injuries can be broadly classified into contact and noncontact injuries. Noncontact injuries occur with the knee in slight flexion, valgus, and internal rotation, and contact injuries typically involve a lateral-side impact producing a valgus force to the knee. The valgus component of noncontact injuries has been thought to cause mainly lateral compartment bone bruising. Posterior translation is the most common mechanism of posterior cruciate ligament rupture, and hyperextension and varus is associated with posterolateral corner injury.

DISCUSSION: MRI reveals an anterior labral tear, and the radiograph shows minimal arthritis with possible dysplasia. The most common location of pain in patients with a labral tear is the groin, and the most common physical finding is a positive impingement test result. Pain during sitting, clicking, and buttock pain are frequently described by patients with a labral tear, but these symptoms are less common than groin pain. A positive posterior impingement test finding is more common in patients with a posterior labral tear. Although age over 40 years and a body mass index higher than 30 can adversely affect clinical outcomes after joint preservation procedures such as PAO, hip arthroscopy, and femoral acetabular impingement surgery, the presence of hip arthritis on presurgical radiographs is the most commonly mentioned cause of failed hip joint preservation surgery. Tönnis grade is a radiographic measure of hip arthritis. A higher Outerbridge score is associated with more frequent poor outcomes after hip arthroscopy; however, the Outerbridge cartilage score is determined by direct visualization at the time of surgery. The Outerbridge score cannot be determined presurgically.

Cadaveric studies have demonstrated the important role of the posterior horn of the medial meniscus in stabilizing the anterior cruciate ligament-deficient knee with significantly greater resultant force in the medial meniscus when subjected to anterior tibial loads. The posterior horn of the medial meniscus is thought to limit anterior tibial translation by acting as a buttress by wedging against the posterior aspect of the medial femoral condyle. The other soft tissues mentioned do not play any significant role in prevention of anterior tibial translation in the anterior cruciate ligament-deficient knee.

A tear of the mid portion of a stable discoid lateral meniscus should be treated with a partial menisectomy with saucerization. Lateral total menisectomy is contraindicated because of the poor long-term results following this procedure. Meniscal transplant and casting do not have a role in this scenario, although meniscal repairs may be needed for peripheral meniscal instability.

This patient has cam-type femoroacetabular impingement. Decreased internal rotation and a positive impingement test (forced flexion, adduction, and internal rotation) are classic findings. The lack of pain with resisted hip flexion makes hip flexor strain unlikely, and the lack of tenderness at the greater trochanter renders trochanteric bursitis unlikely. Although athletic pubalgia can be a source of longstanding groin pain, he lacks the pain with a resisted sit-up and tenderness along the pubic ramus that is frequently noted in patients with pubalgia. His radiographs reveal a focal femoral neck prominence consistent with cam impingement, although pistol grip deformities and flattening of the lateral femoral head are often present as well. His MRI scan shows a labral tear, which is common in cam impingement. Surgical treatment for cam impingement can be effective for symptomatic patients. Even among high-level athletes, open surgical dislocation of the hip has been shown to have good results. Most patients with cam impingement can be treated with arthroscopic osteoplasty and achieve results comparable with those realized with open surgical dislocation. The literature describes success in terms of athletes returning to sports (even professional athletes) to be approximately 90% after arthroscopic treatment. Byrd and Jones described five patients who developed transient neurapraxias that resolved uneventfully. The patients in his series who had concomitant microfracture had a 92% return to sports within the follow-up period. Cam impingement has long been thought to be associated with a history of a slipped capital femoral epiphysis. The capitis in these patients is displaced posteriorly, resulting in a prominent anterior femoral neck and decreased hip internal rotation. Pincer impingement is associated with a deep acetabulum, such as protrusion acetabula and acetabular retroversion. A patient who underwent aperiacetabular osteotomy can develop a more retroverted acetabulum as well.

DISCUSSION: Subtle anterior subluxation in the throwing athlete most frequently results from excessive capsular laxity because of repetitive microtrauma. Avulsion of the inferior glenohumeral ligament from the glenoid, or more rarely from the humerus, occurs with macrotrauma. A large Hill-Sachs lesion and a glenoid rim fracture also may result from a traumatic anterior dislocation. REFERENCES: Kvitne RS, Jobe FW: The diagnosis and treatment of anterior instability in the throwing athlete. Clin Orthop 1993;291:107-123. Jobe FW, Tibone JE, Jobe CM, Kvitne RS: The shoulder in sports, in Rockwood CA Jr, Matsen FA III (eds): The Shoulder, ed 2. Philadelphia, PA, WB Saunders, 1999, pp 961-990.

In an asymptomatic athlete, what condition represents an absolute contraindication to returning to contact or collision sports?A. Healed one-level anterior cervical fusionB. Congenital atlanto-occipital fusionC. Cervical disk herniation previously treated nonoperativelyD. Spina bifida occultaThe one overriding principle regarding the return to any collision sport, as Torg and associates has described, is that the athlete be "neurologically intact, asymptomatic, and pain-free and have full strength and full cervical range of motion". Forces exerted on the cervical spine can be absorbed by the "elasticity of the intervertebral disk, the mobility of the spine itself, and the impact of absorbing capabilities of the cervical paravertebral musculature". The C1 and C2 levels (atlanto-occipital level) control movement of the skull and articulate the large motion movements. Specifically, partial or complete 56congenital fusion of the atlas to the base of the occiput results in progressive cord compression by the posterior lip of the foramen magnum. It can result in sudden death.A cervical disk herniation that was previously treated nonsurgically and is not causing cord compression in the currently asymptomatic patient is not a contraindication to return to collision sports. Spina bifida occulta is common (10-20% of healthy individuals). It is typically an incidental finding and does not result in neurologic problems. If individuals have a healed anterior, lateral or posterior disk herniation that is treated nonsurgically and they are currently asymptomatic, then there is no contraindication to participation in contact sports. If they require a diskectomy and fusion and they have a solid/healed fusion, are asymptomatic and neurologically intact with full and pain-free range of motion, then there is no contraindication to return to collision sports. An acute disk herniation, a disk herniation with associated pain or neurologic symptoms, or the presence of cord compression or loss of normal lordosis are all contraindications.71- Based on the injury shown on the axial MRI scan of the shoulder in Figure 1, what other pathology should be closely examined for during surgery?A. Subscapularis tearB. Supraspinatus tearC. Superior labral anterior- posterior (SLAP) tearD. Bankart tearThe axial MRI scan reveals a subluxated biceps tendon. In the study by Koh and associates, 85% of patients with a biceps subluxation on MRI were found to have a subscapularis tear at the time of arthroscopy. These are not always obvious on the MRI, and close inspection of the leading edge/upper border of the subscapularis tendon at the time of arthroscopy is necessary. Although supraspinatus tears, SLAP tears, and Bankart tears can all occur in conjunction with a biceps subluxation, none have been shown to be strongly correlated with this pathology, nor as specific to this pathology.73- Figures 1 through 4 are the MRI scans of a 24-year-old former collegiate basketball player who injured his left knee while playing recreational basketball 10 days prior to presentation. He landed from a jump awkwardly and reported that his knee gave out. He heard a pop at the time of injury and was unable to continue playing. He complains of medial and lateral knee pain and difficulty with weight bearing. On physical examination, he has a moderate effusion and his range of motion is from 10° to 80°. Ligament examination reveals a 2B Lachman, negative posterior drawer as well as negative varus and valgus stress testing. What is the diagnosis?A. Meniscus tearB. Anterior cruciate ligament (ACL) tearC. ACL tear and posterior cruciate ligament (PCL) tearD. ACL tear and medial meniscus tear

Technical failure is the most common reason for ACL reconstruction failure. Tunnel position is the most frequent cause for technical failure. Malpositioning of the tunnel affects the length of the graft, causing either decreased range of motion or increased graft laxity. Although graft choice is an important factor when planning an ACL reconstruction, overall outcomes with autograft tissues are fairly similar. Fixation of the graft at the femoral or tibial end is not as important as tunnel position.

DISCUSSION: Chronic rotator cuff tears should be nonsurgically managed initially with a strengthening program. A cortisone injection may reduce inflammation. Surgery is reserved for patients who continue to have pain and lose sleep despite the use of physical therapy. Blood tests for infection or inflammation are nonspecific. Arthroscopy may play a role, but surgical replacement is reserved for advanced cases. REFERENCES: Bokor DJ, Hawkins RJ, Huckell GH, et al: Results of nonoperative management of full-thickness tears of the rotator cuff. Clin Orthop 1993;294:103-110. Wirth MA, Basamania C, Rockwood CA Jr: Nonoperative management of full-thickness tears of the rotator cuff. Orthop Clin North Am 1997;28:59-67.

DISCUSSION: The MRI scan shows detachment of the subscapularis from its insertion on the lesser tuberosity. The examination finding is consistent with a positive lift-off test, also indicating a tear of the subscapularis. REFERENCES: Lyons RP, Green A: Subscapularis tendon tears. J Am Acad Orthop Surg 2005;13:353-363. Warner JJ, Higgins L, Parsons IM, et al: Diagnosis and treatment of anterosuperior rotator cuff tears. J Shoulder Elbow Surg 2001;10:37-46.

Injuries to the MCL usually result from repetitive high valgus stress on the medial aspect of the elbow joint due to overhead throwing or racquet sports. Excessivestresses during the late cocking and acceleration phase of throwing can injure the anterior band of the MCL. Clinically, the injuries may present as chronic or acute, and a pop may be noted in the latter. Associated ulnar nerve involvement is common. Valgus instability is present in about 25% of patients. Patients typically are athletes who participate in throwing and have localized medial elbow pain and tenderness along the course of a ligament that extends from the medial epicondyle of the distal humerus to the sublime tubercle of the ulna. Surgical reconstruction is the procedure of choice in an athlete desiring a return to a high level of throwing.

DISCUSSION: The suprascapular nerve passes through the suprascapular notch and the spinoglenoid notch before innervating the infraspinatus muscle. At both locations, the suprascapular nerve is prone to nerve compression, which often results from a ganglion cyst. The other anatomic locations are not associated with suprascapular nerve impingement. REFERENCES: Romeo AA, Rotenberg DD, Bach BR: Suprascapular neuropathy. J Am Acad Orthop Surg 1999;7:358-367. Post M, Mayer J: Suprascapular nerve entrapment: Diagnosis and treatment. Clin Orthop 1987;223:126-136.

DISCUSSIONAxillary lateral and anteroposterior (AP) images of the right shoulder (Figures 59c and 59d) reveal osteoarthrosis of the glenohumeral joint, which typically is not associated with significant rotator cuff pathology. An examination often shows limitations in range of motion, crepitance, and pain with motion. An AP radiographic image of the right shoulder (Figure 59b) reveals proximal humeral migration, which normally correlates with rotator cuff tear size. Tears extending into the infraspinatus tendon are associated with more humeral migration than is seen with isolated supraspinatus tears. Presenting complaints are usually of pain and weakness. Examination findings include subacromial crepitance and weakness during rotator cuff testing. Rarely, this may be associated with pseudoparalysis in large uncompensated rotator cuff tears. The CT image of the right shoulder (Figure 59a) shows superior migration of the humerus with respect to the glenoid surface and end-stagedegenerative changes at the glenohumeral joint. These changes are classified as rotator cuff arthropathy. Pain and weakness are common, as is the presence of pseudoparalysis and limited range of motion.RECOMMENDED READINGSKelly JD Jr, Norris TR. Decision making in glenohumeral arthroplasty. J Arthroplasty. 2003 Jan;18(1):75-82. Review. PubMed PMID: 12555187.View Abstract at PubMedKeener JD, Wei AS, Kim HM, Steger-May K, Yamaguchi K. Proximal humeral migration in shoulders with symptomatic and asymptomatic rotator cuff tears. J Bone Joint Surg Am. 2009 Jun;91(6):1405-13. doi: 10.2106/JBJS.H.00854. PubMed PMID:

The radiographs and CT scans indicate a comminuted and displaced intra-articular fracture of the distal humerus. Rigid internal fixation with bicolumnar orthogonal or parallel plating is the treatment of choice for most fractures of the distal humerus that involve the joint surface. Closed reduction and variations thereof will not yield a stable environment for healing. To achieve adequate exposure for fixation, a chevron olecranon osteotomy is the preferred approach. Disadvantages associated with this approach include complications such as nonunion of the osteotomy site and intra-articular adhesions. Prominent hardware may need to be removed during a secondary procedure, and intraoperative conversion to an elbow arthroplasty may be limited. The most common complications after open reduction and internal fixation include elbow stiffness, nonunion (2%-10%), and ulnar neuropathy (0%-12%).

DISCUSSION: The anterior cruciate ligament can be visualized on an axial MRI scan as a low-signal structure lying in the lateral aspect of the intercondylar notch. Visualization in multiple planes increases the accuracy of MRI to view the anterior cruciate ligament. The posterior cruciate ligament and ligament of Wrisberg are located on the medial wall of the notch. The ligamentum mucosum is anterior to the notch, and the popliteus tendon is posterior to the lateral femoral condyle. REFERENCES: Resnick D, Kang HS (eds): Internal Derangements of Joints: Emphasis on MR Imaging. Philadelphia, PA, WB Saunders, 1997, pp 675-699. Fitzgerald SW, Remer EM, Friedman H, Rogers LF, Hendrix RW, Schafer MF: MR evaluation of the anterior cruciate ligament: Value of supplementing sagittal images with coronal and axial images. Am J Roentgenol 1993;160:1233-1237.

DISCUSSION: Subscapularis tendon tears are being recognized with increasing frequency, and the mechanism of injury involves hyperabduction and external rotation. The patient will have anterior shoulder pain and may report a sensation of instability. Examination will reveal anterior shoulder tenderness over the lesser tuberosity and bicipital groove, and the Gerber lift-off test usually is positive. The MRI scan shown here reveals an intact anterior labrum. The subscapularis tendon is avulsed and retracted, with no evidence of the biceps tendon within the groove; this implies dislocation of the biceps, a common accompanying feature of a subscapularis tear. This injury is also recognized as a complication after open anterior shoulder stabilizations where the subscapularis has been incised as part of the approach. Therefore, the appropriate management involves repair of the subscapularis. The injury does not represent a recurrence so immobilization or revision stabilization, which may be reasonable treatment for recurrent instability, is not indicated. The findings are not consistent with a superior labral tear. REFERENCES: Deutsch A, Altchek DW, Veltri DM, et al: Traumatic tears of the subscapularis tendon: Clinical diagnosis, magnetic resonance imaging findings, and operative treatment. Am J Sports Med 1997;25:13-22. Gerber C, et al: Isolated rupture of the subscapularis tendon. J Bone Joint Surg Am 1996;78:1015-1023.

Figures 1 through 3 are the MRI scans of a 15-year-old boy who sustained an injury to his shoulder after a fall while playing soccer. Following completion of a month-long rehabilitation program, he is able to tolerate sports-specific drills without symptoms. The patient is eager to return to play, as it is mid-season. How should the patient be counseled?

DISCUSSION: In the skeletally mature individual, this mechanism of injury will often result in a sprain of the medial collateral ligament. In skeletally immature patients, the same mechanism can cause a fracture of the distal femoral physis. If the fracture is nondisplaced, the plain radiographs may show only soft-tissue swelling or effusion. While the MRI scan may show edema in the soft tissues on the medial side of the knee and even an abnormality of the physis, stress radiographs provide a quicker and less expensive means of making the diagnosis. Arthroscopy and arthrography would not be helpful in making the diagnosis. Arthroscopy may result in further displacement of the injury. REFERENCES: Smith L: Concealed injury to the knee. J Bone Joint Surg Am 1962;44:1659-1660. Beaty JH, Kumar A: Fractures about the knee in children. J Bone Joint Surg Am 1994;76:1870-1880.

DISCUSSION: Heat stroke consists of hyperthermia (greater than 105.8 degrees F [41 degrees C]), central nervous system dysfunction, and cessation of sweating with hot, dry skin. It is a medical emergency that results from failure of the thermoregulatory mechanisms of the body. It has a high death rate and requires rapid reduction in body core temperature. Heat syncope is characterized by a transient loss of consciousness with peripheral vasodilation and decreased cardiac output with normal body temperature. Heat cramps involve painful contractions of large muscle groups because of decreased hydration and a decrease of serum sodium and chloride. Heat exhaustion is distinguished by a core temperature of less than 105.8 degrees F.