Rotator cuff tear and acromioclavicular joint cyst.

A 58 year old man is described who developed a subcutaneous synovial cyst over the acromioclavicular joint. The cyst developed in association with a massive tear of the rotator cuff and the long head of the biceps, which was demonstrated by arthrography. A loose fragment of the acromion was found intraoperatively. The patient was treated surgically by a combination of excision of the cyst, acromioplasty, removal of the loose acromial fragment, and a duramater allograft to close the rotator cuff defect. The functional result was unsatisfactory.