Reverse Prosthesis Through a Superior Approach for Cuff Tear Arthropathy

Abstract

Arthroplasty in cuff tear arthropathy is the most difficult and challenging issue in shoulder practice. Many prosthesis designs have been developed during the last decades, but all of them disappeared due to early loosening, mainly of the glenoid component. For more than 10 years, a semiconstrained prosthesis (Reverse Prosthesis Delta3®) with a new design philosophy and improved biomechanical properties has been used in clinical practice. It is designed as a total shoulder arthroplasty for pain relief and restoration of function for pathologic surfaces of the glenohumeral joint due to any reasons, accompanied by extensive irreparable cuff defects performed by an anterior-superior approach. The only prerequisites are a structural and neurogenic intact deltoid muscle and a sufficient glenoid bone stock. Because of the absence of major parts of the rotator cuff, the superior transdeltoidal approach makes an easy access to the glenoid possible. The anterior parts of the deltoid are minimally detached from the acromion. The implantation of the prosthesis can be carried out by a minimally invasive approach. The preparation and refixation of the deltoid are critical steps of the operative procedure. Between October 1997 and June 2002, a reverse total shoulder arthroplasty was done in 63 patients; 56 patients were available for a clinical and radiologic follow-up. The mean age at operation was 67.1 years; average follow-up time was 39 (24-81) months. Ninety-eight percent of patients would agree to repeat surgery. Average Constant Score adjusted to age and gender was 90.1%, and it was 97% for patients not having undergone previous surgery. All patients reported complete or almost complete pain relief. All functional parameters were normal for the patient's age, with the exception of a slight limitation of internal rotation (average L5). The abduction power was a little less than the opposite side but corresponded in general to age-specific values. During the follow-up period, 19.5% developed high-grade inferior glenoid bone erosions reaching or surpassing the inferior screw (grade 3 or 4); 2 (1 septic, 1 aseptic) glenoid base plate loosenings occurred.