1. Radiographs of both shoulders were performed on 106 unselected necropsy subjects and those found to be abnormal were examined pathologically. 2. Radiological abnormalities were found in sixty-eight shoulders of thirty-eight subjects. Pathological examination showed rotator cuff tears and associated abnormalities in thirty-five of these, rheumatoid arthritis in one, a previous fracture in one, and one was not examined. 3. The criteria for radiological diagnosis of rotator cuff tears are examined and discussed. 4. The radiological changes give little indication of the severity of the tears or associated abnormalities except in the case of complete rupture of the cuff when acromio-humeral articulation occurs. 5. The lesions are all explicable on a traumatic basis. There is no correlation with the presence or absence of osteoarthritic disease of the joint. 6. The biceps tendon may become damaged or even ruptured in this condition. 7. Villous synovial proliferation was found in fourteen cases, in five of which it was pigmented with histological appearances resembling pigmented villonodular synovitis. The significance of this finding is briefly discussed.
