Dislocation arthropathy of the shoulder.
Seventy-four shoulders in seventy patients with a history of single or multiple dislocations of the shoulder demonstrated radiographic evidence of glenohumeral arthropathy. In every patient radiographs of the contralateral shoulder failed to reveal any abnormality (except, of course, in patients with bilateral dislocation). There were sixty-two anterior and eleven posterior dislocations, and one multidirectional dislocation. Shoulders with a posterior dislocation had a much higher incidence of moderate and severe arthrosis than those that had an anterior dislocation. This seemed to be related to delay in diagnosis. The number of recurrent dislocations or the presence of defects of either the glenoid rim or the humeral head, or both, was not related to the severity of the arthrosis. Operations in which internal fixation devices intruded on joint cartilage frequently resulted in moderate to severe arthrosis. Ten of the fifteen shoulders with severe arthrosis and six of the fourteen with moderate arthrosis had had no operation for the dislocation. Six of these sixteen shoulders had had a posterior dislocation for which reduction had been delayed.