Outcome after cup hemiarthroplasty in the rheumatoid shoulder - A retrospective evaluation of 39 patients followed for 2-6 years

33 rheumatoid patients, treated with hemispherical cup resurfacing hemiarth roplasty of the shoulder without medullary fixation (6 bilaterally), were r eviewed after mean 4.4 (2-6) years. The median Constant score was 30 (15-79 ), mean proximal migration of the humerus 5.5 (SD 5.2) mm and mean glenoid erosion 2.6 (SD 1.7) mm. Proximal migration and glenoid erosion did not cor relate with shoulder function or pain. Radiographic signs of loosening (cha nges in cup inclination combined with changes in cup distance above the gre ater tuberosity) occurred in one quarter of the shoulders. At follow-up, 26 patients were satisfied with the procedure, despite poor shoulder function and radiographic deterioration.