Anatomic total shoulder arthroplasty for osteoarthritis in patients who are 75 years or older. An analysis of revision rates and patient-reported outcome using data from the Danish shoulder arthroplasty registry

Background: Anatomic total shoulder arthroplasty (aTSA) has been proven effective in the treatment of painful end-stage osteoarthritis in patients with intact rotator cuff function. However, elderly patients may have an increased risk of revision, especially when it comes to the risk of revision due to loosening, rotator cuff pathology and periprosthetic fracture. The aim of this study was to investigate revision rates and patient-reported outcomes after aTSA for osteoarthritis in patients who are 75 years or older. We hypothesized that revision rates and patient-reported outcomes were similar for patients aged 55-74 years and 75 years or older. Methods: This is a registry-based cohort study with data from the Danish Shoulder Arthroplasty Registry. For analysis, 1,884 aTSAs used for osteoarthritis between January 1, 2012, and December 31, 2019, were included. Patients were divided into 2 age groups: 55-74 years and 75 years or older. The Kaplan–Meier method was used to estimate unadjusted cumulative revision rates and a multivariate Cox regression model was used to determine hazard ratios. A multivariable linear regression model was used to compare the Western Ontario Osteoarthritis of the Shoulder Index (WOOS) 1 year postoperatively. Results: There were 34 (2.5%) patients in the middle-aged group and 8 (1.6%) patients in the older age group who had revision surgery. The hazard ratio for revision was 0.67 for the older age group compared to the middle-aged group (95% confidence interval [CI] 0.31-1.47, P = .32). The unadjusted 2-year and 5-year cumulative revision rates were 2.3% (95% CI 1.4-3.2) and 3.6% (95% CI 2.3-4.9) in the middle-aged group and 1.7% (95% CI 0.4-3.0) and 2.2% (95% CI 0.6-3.8) in the older age group. The mean WOOS score was 84 (standard deviation = 20) in the middle-aged group and 85 (standard deviation = 20) in the older age group. The difference in WOOS between the 2 groups was 1.2 points (95% CI −1.5 to 3.8, P = .40). Conclusion: We found low short-term revision rates and good patient-reported outcomes for both middle-aged and older patients treated for osteoarthritis using aTSA. The small differences in WOOS between the 2 age groups were not clinically relevant nor statistically significant. aTSA provides good and reliable outcomes in elderly patients with end-stage osteoarthritis, and age alone should not be a reason for opting out aTSA.