Abstract
The rotator cuff is often severely damaged in arthritis of the shoulder and there is no satisfactory technique for its repair. patients with a ruptured cuff and an eroded glenohumeral joint may have intractable pain, and standard methods of joint replacement are then inappropriate. A ball and socket prosthesis has been designed to replace the function of both the rotator cuff and the glenohumeral joint. Mechanical testing has shown that the scapular cup can be securely fixed. The outcome in 71 shoulders operated upon since 1973 is reported.