The painful shoulder is a well-recognized clinical entity in throwers although the pathogenic mechanisms involved are still debated. In 1991 Walch then Jobe developed the concept of posterosuperior impingement to explain lesions observed arthroscopically. This impingement between the deep aspect of the supraspinatus tendon and the glenoid occurs during loaded arm movements. The purpose of this work was to study the different types of lesions observed arthroscopically and to analyse outcome after arthroscopic debridement.