5. Sports Medicine MCQs

Two-dimensional CT scan is generally accepted as a superior imaging modality for evaluating bone loss in shoulder instability than two-dimensional MRI scan. This advantage is offset by the relatively high radiation dose. Although CT in most situations is less costly, MRI can provide more data regarding associated soft-tissue damage that can be associated with recurrent instability. It should be noted that three-dimensional MRI has recently been shown as equivalent to three-dimensional CT in its ability to identify glenoid bone loss.

Although this player limps off the field, the fact that he felt dizzy, had a headache, and did not initially recognize that he was playing in the third quarter indicates that he sustained a concussion. The player should be kept out of the game until a cognitive examination and repeat physical assessment is completed. The Consensus Statement on Concussion in Sport recommends that no athlete with concussion symptoms be returned to same-day play. This patient still has a slight headache, but even if this resolved he should not return to the game. Adolescents and high school athletes may have neurophysiological deficits that may not be evident on the sideline, or they may have a delayed onset of symptoms. A graduated return to play for future games is recommended.

In a large series of mini-open rotator cuff repairs, an infection rate of at least 2% was found, with the majority of the infections caused by Propionibacterium acnes. To prevent this complication, the shoulder should be re-prepped before the mini-open incision is made to prevent bacterial contamination from the arthroscopic procedure.

The middle genicular artery supplies the posterior capsule and intracapsular structures (anterior cruciate ligament, posterior cruciate ligament, posterior horns of the meniscus).

DISCUSSION: The leg and trunk provide a stable base for arm motion, supply rotational momentum for force generation, and generate 50% to 55% of the total force and kinetic energy in the tennis serve. REFERENCES: Garrick JG (ed): Orthopaedic Knowledge Update: Sports Medicine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, p 47. McClure PW, Michener LA, Sennett BJ, et al: Direct 3-dimensional measurement of scapular kinematics during dynamic movements in vivo. J Shoulder Elbow Surg 2001;10:269-277. Burkhart SS, Morgan CD, Kibler WB: The disabled throwing shoulder: Spectrum of pathology. Part III: The SICK scapula, scapular dyskinesis, the kinetic chain, and rehabilitation. Arthroscopy 2003;19:641-661.

This patient has internal snapping hip (coxa saltans), which is caused by the psoas tendon sliding over femoral head, iliopectineal ridge, lesser trochanter exostoses, or iliopsoas bursa.Snapping hip exists in 3 forms: (1) external snapping hip, which is caused by the iliotibial band (ITB) sliding over the greater trochanter, (2) internal snapping hip, and(3) intraarticular snapping hip, which is caused by loose bodies (traumatic, or from synovial chondromatoses) or labral tears. While painless snapping hip requires no treatment, painful snapping hip may be addressed with activity modification, physical therapy, steroid injections. Surgical release (ITB z-plasty or psoas tenotomy) is indicated if nonoperative management is unsuccessful.Ilizaliturri et al. evaluated the results of endoscopic iliopsoas tendon release at the lesser trochanter (10 patients) vs endoscopic transcapsular psoas release from the peripheral compartment (9 patients). There were improvements in WOMAC scores in both groups, and no difference between groups. They conclude that both techniques are equally effective.Marquez Arabia et al. evaluated if the psoas tendon regenerates after tenotomy in 27 patients. At 23 months, they found that tendon regeneration occurred in all patients, toa mean circumference of 84% of the original. One patient had persistent pain, but all had 5/5 hip flexion strength. They hypothesize that the bulk of iliopsoas muscle fibers attaches directly to the proximal femoral shaft without a tendon, preventing retraction and allowing regeneration to occur easily.Figure A shows pre- and post-operative arthroscopic psoas tenotomy magnetic resonance sagittal images. Illustration A shows the psoas tendon (white arrows) prior to transection. Illustration B shows the psoas tendon after transection (green arrows, proximal tendon segment; yellow arrows, distal segment). Illustration C and D are diagrams showing release at the level of the lesser trochanter and hip joint respectively.Incorrect90 degrees, but full external rotation. Answer 2: Decreased internal rotation and a positive impingement test (forcedflexion, adduction, femoroacetabular Answer 4: Theseand internalrotation) are classic findingsfindings maybe found with intra-articularfor cam-type impingement loose bodies.

The rugby player has sustained an injury to his anterior cruciate ligament (ACL), as demonstrated by the Segond fracture on radiograph and bone-bruising pattern on magnetic resonance imaging (MRI). The presence of a Segond fracture (avulsion fracture of the proximal lateral tibia) is pathognomonic for an ACL rupture.

Hyponatremia (“water intoxication”) can occur in endurance athletes such as ultramarathoners who are sweating profusely and drinking only water as fluid replacement. With hyponatremia, the serum sodium is abnormally low, resulting in brain swelling, seizures, coma, and potentially death.

A rib stress fracture, the most common injury to the thorax in rowing athletes, generally occurs during periods of intense training with a low stroke rate and heavy loads. It is characterized by the sudden onset of sharp, localized chest pain while rowing.

Quadrilateral space syndrome is a rare condition resulting from compression of the contents of the quadrilateral space. The contents of the quadrilateral space include the posterior circumflex humeral artery and the axillary nerve.

The radiograph shows a Segond fracture, an avulsion fracture involving the lateral capsular ligament. This radiographic finding has been associated with ACL rupture in 75% to 100% of cases. Drilling the femoral tunnel through the anteromedial portal allows for independent access to the native femoral attachment. Fiber orientation is more oblique than with a transtibial technique and more closely resembles that of the native ligament. Double-bundle reconstruction attempts to duplicate native ACL anatomy. Biomechanical studies have shown that double-bundle reconstruction more closely reproduces normal knee kinematics; however, this technique does not offer a clear advantage in terms of clinical outcomes. Double-bundle reconstruction is associated with higher surgical costs because of the need for additional fixation and, in the case of allograft reconstruction, a second graft.

This patient has an isolated supraspinatus rotator cuff tear with symptomatic weakness. The most appropriate treatment would be isolated rotator cuff repair.The primary purpose of rotator cuff repair is to restore muscle function. Secondary outcomes include reduction of pain and prevention of irreversible cuff changes, specifically muscular atrophy. Non-operative treatment (exercise, therapy and pain medications) are recommended for partial thickness tears. The indication of surgical repair includes, isolated supraspinatus weakness +/- pain that correlates with MRI imaging of a respective full thickness tear. Routine acrominoplasty is not recommended in conjunction with rotator cuff repair, especially with no previous symptoms of impingement.Pedowitz et al. developed clinical practice guidelines for the treatment of rotator cuff pathology. The strongest supporting evidence in current literature was given a grade of 'moderate' with four treatment recommendations. These were,Exercise and non-steroidal anti-inflammatory drugs can be used to manage partial thickness tears,Routine acromioplasty is not required the time of cuff repair,Non-cross-linked, porcine small intestine submucosal xenograft patches should not be used to manage cuff tears, andSurgeons can advise patients that workers' compensation status correlates with a less favorable outcome after rotator cuff surgery.Illustration A shows the different shapes of rotator cuff tears. Incorrect Answers:

DISCUSSION: 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.

DISCUSSION: The figure shows the anterolateral portal for elbow arthroscopy, and injury to the radial nerve has been reported in conjunction with this portal site. Studies have shown that closer proximity to the radial nerve is associated with more distal portal sites. The lateral and posterior antebrachial cutaneous nerves are both at less risk of injury. The ulnar and median nerves are both fairly remote to this location.

DISCUSSION: The most reliable test for a relatively isolated posterolateral complex (PLC) injury is the asymmetric tibial external rotation or “dial test.” It can be performed with the patient prone or supine. When greater than 10 degrees of external rotation at 30 degrees of flexion is present when compared with the opposite knee, it indicates significant damage to the posterolateral structures. Asymmetric external rotation, which is also present at 90 degrees of flexion, indicates injury to the posterior cruciate ligament (PCL) as well. Varus laxity may indicate significant damage to both the PLC and PCL. Approximately 35% of the normal population may have a reverse pivot shift when examined under anesthesia; therefore, it is considered a less specific test. The external rotation/recurvatum and posterolateral drawer tests are adjunctive in assessing isolated posterolateral laxity but are not thought to be as reliable.

This athlete has a symptomatic posterior-superior labral tear, spinoglenoid notch cysts, and subsequent suprascapular nerve compression, as evidenced by the atrophy of the infraspinatus muscle on sagittal T1 MRI. The cyst is located at the spinoglenoid notch and is compressing the suprascapular nerve after it has innervated the supraspinatus but before innervation of the infraspinatus; hence, the atrophy of infraspinatus on examination and imaging. Compression of the suprascapular nerve at the suprascapular notch would lead to weakness and atrophy of both the supraspinatus and infraspinatus. The lower subscapular nerve innervates the teres major, as well as, with the upper subscapular nerve, thesubscapularis. The teres minor is innervated by the axillary nerve.

While the patellar tendon ligament is considered by many to be the tissue of choice for ACL reconstruction, more recent studies have shown that the quadruple semitendinosus and gracilis tendon graft has the greatest stiffness and offers the highest maximum load to failure.

For lesions >2 cm², ACI is preferred over microfracture. Microfracture relies on marrow stimulation and results in fibrocartilage repair (predominantly Type I collagen), which is less durable under shear and compressive loads. ACI (a two-stage procedure) results in the formation of hyaline-like cartilage (predominantly Type II collagen and aggrecan), providing superior long-term durability for larger defects.

Cam-type FAI is caused by an aspherical femoral head-neck junction (loss of native concavity). It is most accurately quantified using the alpha angle, typically measured on a Dunn lateral or frog-leg lateral radiograph (or MRI). An alpha angle >50-55 degrees indicates cam morphology. A crossover sign indicates pincer-type FAI (acetabular retroversion). Lateral center-edge angle <20 and high Tonnis angle denote hip dysplasia.

In the OATS procedure (mosaicplasty), cylindrical osteochondral grafts are harvested from a non-weight-bearing or low-contact-pressure area of the knee to treat a defect in a high-weight-bearing area. The ideal and most common donor sites are the periphery of the lateral trochlear ridge (superolateral margin of the lateral condyle) or the medial superomedial trochlear margin, as these areas experience minimal contact pressures.