[Posterosuperior glenoid rim impingement in athletes: the diagnostic value of traditional radiology and magnetic resonance].

First described by Walch in 1991, the posterosuperior glenoid rim impingement syndrome is a major condition in the differential diagnosis of shoulder pain occurring in the athletes engaged in repetitive and loading movements of abduction and extra-rotation of the dominant upper limb. Thirty-eight athletes with these dynamic athletic characteristics, referred for unexplained shoulder pain and with a clinical diagnosis of posterosuperior glenoid rim impingement syndrome, underwent radiography and MR examinations, with excellent final results. Radiography was capable of depicting the abnormal skeletal features of this kind of impingement, thus allowing a preliminary diagnosis to be made. MRI excelled in diagnosing the lesions in the deep surface of the supraspinatus tendon and in the posterior labrum secondary to impingement. The static and the kinematic sequences with the arm in abduction and extrarotation proved to be the best ones to define the physiopathologic phases of impingement. Thus, we conclude that invasive diagnostic procedures are not necessary for the correct and unquestionable diagnosis of posterosuperior glenoid rim impingement syndrome.