Shoulder arthroplasty for the treatment of inflammatory arthritis.

BACKGROUND

Prosthetic replacement of the glenohumeral joint can relieve pain and improve shoulder function for patients with end-stage inflammatory arthritis. The purpose of this study was to prospectively analyze the clinical, functional, and radiographic outcomes of shoulder reconstruction with hemiarthroplasty or total shoulder arthroplasty.

METHODS

In this multicenter prospective study, clinical history, physical examination, and self-assessment tools including a visual analogue scale, the Simple Shoulder Test, and an activities questionnaire were used to measure comfort, quality of life, and function. Radiographic outcome was determined by assessing the severity of the disease, the adaptation of the prosthesis to the anatomy, the implant position and relationships, and the restoration of glenohumeral alignment.

RESULTS

At the time of follow-up, at a minimum of twenty-four months (mean, thirty-nine months), the thirty-six shoulders treated with a hemiarthroplasty and the twenty-five treated with a total shoulder arthroplasty showed significant improvement (p < 0.0001) as demonstrated by the visual analogue scale and the Simple Shoulder Test as well as improvements in the components of the activities questionnaire. Active forward elevation was significantly better (p < 0.004) after the total shoulder arthroplasties than after the hemiarthroplasties. The presence of extremely severe disease did not affect the clinical outcome. Prosthetic adaptation to the anatomy and restoration of glenohumeral alignment resulted in significant improvement in certain motion parameters and were associated with one another (p < 0.001). Restoration of glenohumeral alignment resulted in significant improvements in overall quality of life (p = 0.038), use of the arm for work and play (p = 0.014), and range of motion (p = 0.0004) compared with those parameters when alignment had not been restored. Glenoid erosion occurred in four of the shoulders treated with hemiarthroplasty. Two of the glenoid components used in the total shoulder arthroplasties loosened.

CONCLUSIONS

Patients with inflammatory arthritis treated with hemiarthroplasty or total shoulder arthroplasty can be expected to have improved comfort, range of motion, and function. Restoration of glenohumeral alignment appears to lead to even greater improvement in these clinical parameters.