Long-term results and implant survival of revision reverse shoulder arthroplasty after a mean follow-up of ten years.

AIMS: With the growing number of primary arthroplasties of the shoulder being undertaken, revision arthroplasty becomes an increasing challenge. Most revisions are of reverse shoulder arthroplasties (RSAs); however, there is a paucity of long-term results.

METHODS

This monocentre retrospective analysis included 101 patients who underwent revision RSA between June 2006 and August 2019. Clinical outcomes were assessed using the Constant-Murley Score (CMS), range of motion (ROM), Simple Shoulder Test (SST), Subjective Shoulder Value (SSV), and satisfaction questionnaires. Implant survival was determined using Kaplan-Meier analysis. Signs of loosening, radiolucent lines, and scapular notching were assessed on routine radiographs. The mean values for the outcomes were compared using a paired t-test for normally distributed data. A multivariate linear regression model was used to assess factors influencing patient satisfaction. Significance was set at p < 0.05.

RESULTS

The cumulative revision-free implant survival rate was 85.0% (95% CI 75.1 to 91.2) at ten years. No significant differences in rates of survival were found between one- and two-stage revisions, nor between initial implants (hemiarthroplasty, total shoulder arthroplasty, and RSA). The 48 patients with complete clinical and radiological evaluation showed significant improvement of the normalized CMS from the mean preoperative values (21.4% (SD 14.4%)) to those at a mean follow-up of ten years (70.3% (SD 28.8%); p < 0.001). Overall, 75% of patients reported being either very satisfied or satisfied. The mean SST score was 67% (29% to 100%) and the mean SSV was 55% (10% to 90%). Inferior scapular notching was found in 29 patients (60%). The grades of notching negatively correlated with clinical outcome (Spearman's Rho 0.36; p = 0.024).

CONCLUSION

Revision RSA yields acceptable long-term functional outcomes and good implant survival for a variety of indications. One- and two-stage revisions had comparable clinical results and survival. Scapular notching was associated with significantly lower clinical outcome and satisfaction, and should be minimized by optimizing reconstruction.