Evolving trends in shoulder arthroplasty: a decade of growth and future projections in comparison with hip and knee arthroplasty

Total shoulder arthroplasty (TSA), especially reverse shoulder arthroplasty, has expanded rapidly, yet contemporary national trends and projections relative to hip and knee arthroplasty are not fully defined. This study evaluates trends of shoulder arthroplasty in the United States from 2012 to 2022 and projects volumes through 2035. The National Inpatient Sample and National Ambulatory Surgery Sample were analyzed using International Classification of Diseases and Current Procedural Terminology codes to identify shoulder, hip, and knee arthroplasty procedures. Annual procedural volume and incidence per 100,000 population were calculated by age and sex. Linear, log-linear, and logistic regression models projected future trends to 2035. Between 2012 and 2022, TSA increased 212% from 55,245 to 172,559 procedures, with incidence rising from 17.6 to 51.7 per 100,000. In the same time period, total hip and knee arthroplasty increased by 45% and 25%, respectively. Shoulder hemiarthroplasty declined by 55%. Growth was observed across all age and sex groups, with the largest increase in patients aged 65 to 74 years. Log-linear projections show that the growth rate of TSA exceeds the growth rate of hip and knee arthroplasty, with estimates in 2035 reaching 334,000 to 905,000 procedures. Our study demonstrates that shoulder arthroplasty continues to grow exponentially while shoulder hemiarthroplasty declines. These trends highlight the importance of healthcare planning, surgical workforce preparation, and patient counseling for an aging population with expanding shoulder arthroplasty indications.