Lesions of the biceps pulley as cause of anterosuperior impingement of the shoulder in the athlete: potentials and limits of MR arthrography compared with arthroscopy

PURPOSE: This study aimed to evaluate the diagnostic possibilities of MR arthrography in the correct identification of complex tears of the biceps pulley and their possible correlation with anterosuperior impingement (ASI) development. MATERIALS AND METHODS: MR arthrography examinations of 23 athletes with clinical suspicion of ASI were reviewed. All examinations were obtained with a 1.5-T unit (Signa Horizon, GE Healthcare). The shoulders were studied with a dedicated surface coil with the patient's arm in the neutral position and in internal and external rotation. In five patients, images in abduction-external rotation (ABER) were obtained. Within 2 month after MR arthrography, the athletes underwent arthroscopic surgery. RESULTS: MR arthrography images showed a spectrum of tears that, according to the Habermeyer classification, were subdivided into four groups: type 1 in three patients; type 2 in five; type 3 in seven; type 4 in eight. At arthroscopic evaluation, one patient presented type 1 lesion, five type 2, five type 3 and ten type 4. During arthroscopic dynamic manoeuvres, ASI signs were observed in three patients with type 3 lesion and in ten with type 4 lesion. CONCLUSIONS: MR arthrography is the imaging modality of choice for evaluating lesions of the rotator interval structures, and only complex lesions of the biceps pulley are related to the development of ASI.