Efficacy of Ultrasound in the Diagnosis of Biceps Tendon Dislocation.

A 25-yr-old man presented with pain and weakness secondary to posttraumatic anterior shoulder dislocation from a traffic accident 3 mos earlier. The patient received 15 sessions of physical therapy but no improvement was observed. On physical examination, minimal swelling of the anterior aspect of the right shoulder and tenderness with palpation were detected. Speed and Yergason tests yielded positive results, and a 2-cm reduction in circumference was determined on the right arm. Muscle strength of right elbow flexion and forearm supination was 4/5. Shoulder internal rotation was restricted by 50%. All laboratory findings, including erythrocyte sedimentation rate, C-reactive protein, and X-ray examination were normal. Musculoskeletal ultrasound (US) revealed that the bicipital groove was empty and the long head of the biceps tendon (LHBT) had dislocated anteromedially with surrounding edema (Fig. 1). The supraspinatus tendon was observed to be intact and a full-thickness tear of the subscapularis tendon was seen (Fig. 2). Despite a trial of conservative treatment including physical therapy and nonsteroidal anti-inflammatory agents, the condition did not improve and the patient was referred to an orthopedic service for surgery. Dislocation of the LHBT out of the bicipital groove is usually linked with tears of the subscapularis tendon or massive rotator cuff tears. It has been stated that there is no specific clinical test correlated to the presence of medial dislocation of the LHBT. Thus, imaging methods such as US, magnetic resonance imaging, and magnetic resonance imaging arthrography are of paramount importance. Magnetic resonance imaging has long been the primary mode of evaluating shoulder pathologies, but US has rapidly assumed a similar role as an imaging modality in the past few years. When compared with other imaging tools, US imaging is practical, noninvasive, inexpensive, and portable. In addition, US has been found to have 100% specificity and 96% sensitivity for subluxation or dislocation. It is important to detect the position of the LHBT on US particularly after traumatic shoulder dislocation, because pathology of the LHBT may have a part in the development of shoulder pain and long-term dysfunction. FIGURE 1 Bicipital groove (BG) and long head of the biceps brachii tendon. The star indicates empty bicipital groove, and the arrow denotes biceps brachii tendon. l, lateral; m, medial.