Abstract
Purpose
to analyze the survivorship of the RSA with a minimum 10 years follow up.
Patients and Methods
Between 1992 and 1999, 145 Delta (DePuy) RSAs have been implanted in 138 patients. It was a mulicentric study. Initial etiologies were gathered as following: group A (92 cases) Cuff tear arthropaties (CTA), osteoarthritis (OA) with at least 2 involved cuff tendons, and massive cuff tear with pseudoparalysis (MCT); group B (39 cases) -failed hemiarthroplasties (HA), failed total shoulder arthroplasties (TSA), and fracture sequelae; and group C (14 cases) rheumatoid arthritis, fractures, tumor, and instability. Survival curves were established with the Kaplan-Meier technique. Two end-points were retained: -implant revision, defined by glenoid or humeral replacement or removal, or conversion to HA; - a poor clinical outcome defined by an absolute Constant score of less than 30.
Results
At the time of review, 47 patients had died with their prosthesis in place and 30 were lost to follow-up. There were 12 revisions, 6 for infections, 3 for glenoid loosening, 1 for dislocation, 1 for glenoid dissociation (by unscrewing), and 1 for humeral loosening.
The survival curve to prosthetic removal showed an overall survivorship of 92% at 10 years. Segmentation according to etiology showed a 97% survivorship for group A and 88% for group B This difference was not significant. No patients of group C had a minimum follow up of ten years because there were died or lost to follow up.
The survival curve to a Constant score of less than 30 showed an overall survivorship of 90% at 10 years. Segmentation according to etiology showed a significant difference at 10 years in favor of group A (92%) compared to group B (86%) with a break of the curve after 9 years for group B.
Discussion
Our results show that the overall survivorship of the reverse shoulder prosthesis to removal is good even 10 years after implantation, in particular if it had been implanted for CTA, OA, or MCT. However, functional results did deteriorate progressively after 9 years in particular if it had been implanted for revision (HA or TSA). Therefore, extreme caution must be observed in relation to the indications for reverse shoulder arthroplasty, especially in younger patients.
