MID-TERM RESULTS OF REVERSED DELTA III SHOULDER PROSTHESES FOR MASSIVE ROTATOR CUFF TEARS

Abstract

Purpose of the study: Treatment of irrepable massive rotator cuff tears remains a controversial issue. The purpose of this study was to assess clinical and radiological outcome in patients with a reversed shoulder prosthesis used for the treatment of irreparable massive rotator cuff tears with or without associated glenohumeral osteoarthritic degeneration.

Material and methods: Between 1996 and 2002, 55 reversed shoulder prostheses were implanted via a superolateral approach. Mean follow-up of the 15 men and 40 women (mean age 73 years, age range 57–86 years) was 34.8 months (range 24–84 months). The supraspinatus and infraspinatus tendons were retracted to the glenoid and ruptured in 100% of the patients: 27 shoulders (49%) also presented a infrascapularis tear. Glenohumeral osteoarthritis (Fukuda IV and V) was persent in 29 patients. Postoperatively, patients were assessed with the Constant score and radiographically on plain x-rays.

Results: Three patients were excluded from the analysis because of implant infection and removal before review. Subjectively, 90% of patients were satisfied or very satisfied. All items of the Constant score improved significantly (p< 0.0001). Active elevation improved from 65° to 123°. External rotation was not improved. Radiographically, there wre 41 shoulders with a grade 0, 1 or 2 notch (Nerot system), and 11 with a grade 3 or 4 notch. Thirteen patients (25%) presented heterotopic ossifications.

Discussion and conclusion: In this context, the clinical results obtained with this prosthesis are much better than with any other type of arthroplasty. Radiographically, heterotopic ossifications have a significant impact on the Constant score (p=0.015). Presence of ta glenoid notch is signifiantly associated with use of a medialized or retaining polyethylene cup (p< 0.0001). For us, loosening of the metaglenoidglenosphere bloc is related to the progression of the glenoid notch. For these reasons, it would be preferable to reserve this type of arthroplasty for patients aged over 70 years presenting an irreparable massive cuff tear with satisfactory glenoid bone stock sufficient for obtaining a good anchor for the metaglen. We recommend only using lateralized polyethylene cups.