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.