Outcomes of shoulder arthroplasty by year of index procedure: are we getting better?

Background: The purpose of this study was to determine whether postoperative patient-reported outcomes improved over time following anatomic total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA).

Methods: We performed a retrospective analysis of prospectively collected patient-reported outcomes from our institution's registry between 2008 and 2018 (N = 1899). American Shoulder and Elbow Surgeons (ASES) scores at a minimum of 2 years postoperatively were required. Univariable linear models were used to test the association between year of surgery and improvement in ASES scores at 2- and 5-year follow-up, as well as any association with age, sex, primary or revision surgery, hand dominance, American Society of Anesthesiologists classification, rotator cuff status, primary diagnosis, and Walch classification. Multivariable models were created to analyze ASES score improvement by index year while controlling for significant factors.

Results: In the univariable analysis, 5-year ASES difference scores increased each year by a mean of 1.65 (P < .001; 95% confidence interval [CI], 0.75-2.55) for TSA, 2.50 (P = .014; 95% CI, 0.52-4.49) for RTSA, and 1.64 (P < .001; 95% CI, 0.81-2.47) for the overall population. Patient sex, American Society of Anesthesiologists classification, rotator cuff status, primary diagnosis, Walch classification, and revision procedures were also significant factors affecting ASES scores. On multivariable analysis controlling for these factors, 5-year ASES difference scores were still significantly associated with year of surgery, increasing each year by a mean of 2.20 (P < .001; 95% CI, 0.91-3.50) for TSA, 4.83 (P < .001; 95% CI, 1.17-8.49) for RTSA, and 1.66 (P < .001; 95% CI, 0.81-2.51) for the entire population.

Conclusion: Both anatomic TSA and RTSA patients reported increasing ASES difference scores at 5-year follow-up as time passed. These findings may indicate that advances in shoulder arthroplasty have resulted in better patient outcomes over time. Further research is needed to clarify which factors influence improvements in outcomes, particularly for revision procedures.