Unconstrained shoulder arthroplasty in rheumatoid arthritis.

The shoulder complex is commonly involved in patients who have rheumatoid arthritis. Highly satisfactory results have been reported after shoulder arthroplasty in patients with rheumatoid arthritis. There is considerable variability in the pathology within the rheumatic glenohumeral joint. Four radiologic patterns have been identified that correlate well with the pathologic findings. The wet pattern is frequently associated with early rupture of the rotator cuff. Certain technical considerations that apply to the performance of shoulder arthroplasty in these patients are addressed herein. Despite early concerns about fixation of the glenoid component, a long-term study performed at the author's institution suggested that this was no greater a problem than loosening of the humeral component, signs of which are increasingly seen with lengthening followup. There is currently a trend toward use of humeral head replacements alone, which may be an acceptable form of management of the rheumatic glenohumeral joint.