MR IMAGING OF SPORTS INJURIES OF THE ELBOW

Overuse Injuries of the Upper Extremity in the Competitive Athlete: Magnetic Resonance Imaging Findings Associated with Repetitive Trauma

Overuse injuries are a very common cause of pain in athletes, accounting for a significant loss of training time and missed competitions. Magnetic resonance imaging (MRI) is playing an increasing role in facilitating the expeditious and safe return of these individuals to their preinjury level of physical performance by allowing accurate diagnosis. Sports physicians are increasingly relying on the exquisite anatomic detail afforded by this technique to formulate diagnoses that assist with the optimal management of these athletic injuries. Some upper extremity overuse entities are well recognized; two examples are medial epicondylitis, classically appearing in baseball pitchers, and lateral epicondylitis, in tennis players. Other less well-known injuries of the upper extremity, such as intersection syndrome in rowers and distal clavicular stress fractures in weightlifters, are frequent occurrences in certain circles of athletes. The following article is a pictorial review of the MRI findings of upper extremity overuse injuries encountered in the competitive athlete, with an emphasis on the sports scenarios in which they occur. We will depict mechanisms of injury and applicable anatomy and show characteristic imaging findings. A wide range of entities are addressed, including but not limited to overuse injuries occurring in baseball, swimming, gymnastics, weightlifting, bowling, and cycling.

Radiographic and special studies: recent advances in imaging of the elbow

Advanced imaging techniques such as computed tomography, ultrasound, and magnetic resonance imaging provide clinically useful information by detecting and characterizing pathologic conditions of the elbow. The information provided by these techniques can help establish an anatomic diagnosis in a noninvasive fashion. A timely and accurate imaging diagnosis may be an important piece of the puzzle in a diagnostic workup that allows implementation of proper treatment and improved outcome. In this article, the authors focus on recent advances in diagnostic imaging of the elbow joint.

The appearance of the lateral ulnar collateral ligament on magnetic resonance imaging

The lateral ulnar collateral ligament is an important element of the elbow's lateral capsuloligamentous complex, and loss of integrity contributes to posterolateral rotatory instability. However, the normal appearance on magnetic resonance imaging is poorly defined. The purpose of this study was to assess the appearance of the lateral ulnar collateral ligament of asymptomatic elbows on magnetic resonance imaging. We performed magnetic resonance imaging on 20 asymptomatic elbows. The lateral ulnar collateral ligament was identified as a hypointense structure originating from the lateral epicondyle and inserting on the proximal ulna in 10 cases (50%) and was ambiguous in the other 10 elbows. The identified lateral ulnar collateral ligament images included areas of high signal intensity, which was confusing because it suggested ligamentous disruption within the ligament. These results indicate that magnetic resonance imaging is not reliable for diagnosing lateral ulnar collateral ligament injuries at the present time. Further progress in magnetic resonance imaging will be clinically useful for diagnosing abnormalities of the lateral ulnar collateral ligament.

Sports injuries in the young athlete

Children and adolescents increasingly are participating in competitive sports, and there has been a corresponding rise in the incidence of sports-related injuries in this group. Many sports injuries follow the same patterns as are seen in adults, but the developing musculoskeletal system is uniquely susceptible to other types of injury. This review describes anatomic and developmental aspects that result in increased susceptibility to injury and the magnetic resonance imaging characteristics of immature cartilage, marrow, and menisci. Injuries that are usually or exclusively encountered in children and adolescents are emphasized.

Stress injury of the proximal ulna in professional baseball players

BACKGROUND

To date, stress injury of the proximal ulna has been infrequently reported as a cause of elbow pain in the throwing athlete.

PURPOSE

We describe a syndrome of osseous stress injury of the proximal ulna in the professional throwing athlete.

STUDY DESIGN

Retrospective review.

METHODS

We evaluated the clinical, radiographic, and magnetic resonance imaging findings of seven professional baseball players with osseous stress injury of the proximal ulna.

RESULTS

Plain radiographs of the involved elbows failed to demonstrate any significant findings. All of the clinically significant lesions were detected with magnetic resonance imaging. In addition, magnetic resonance imaging was found to be of value in following the course of healing of the injuries. All of the lesions originated on the posteromedial aspect of the proximal ulna. The ulnar collateral ligament was intact in all seven athletes. One athlete had two occurrences of this injury. Six of the seven athletes returned to their previous level of play after a nonoperative course of treatment.

CONCLUSIONS

We believe that this injury should be considered in the differential diagnosis of elbow pain in the throwing athlete. Magnetic resonance imaging is the diagnostic test of choice when this injury is suspected.

Imaging of sports injuries in children and adolescents

Imaging plays an important role in the diagnosis and management of sports injuries of childhood and adolescence. The injuries discussed are typical of those seen in the skeletally immature athlete. Imaging specialists must be able to apply the full range of imaging modalities when evaluating the injured young athlete.