Abstract
BACKGROUND: The volume of both anatomic and reverse total shoulder arthroplasty (TSA) has increased in the United States over the last decade. A reduction in length of stay (LOS) postoperatively is a clear way to reduce hospital costs and labor burden. This study aimed to quantify how the LOS reduction has impacted inpatient TSA costs. METHODS: The study queried the National Inpatient Sample (NIS) database to identify individuals undergoing inpatient elective TSA for osteoarthritis from 2012 to 2020. Total costs were determined by multiplying the hospital's cost-to-charge ratio from NIS by the total charges, inflation-adjusted to 2020. Bivariate linear regression assessed the LOS trend, and multivariate gamma regression with log link modeled TSA total cost and charge, adjusting for patient variables and operational year. Predicted total cost and charge were plotted postmodel fitting. Additionally, LOS was standardized to the 2012 mean for model predictions. RESULTS: Numbers are reported as national estimates. In all, 527,300 patients were identified with an average age of 69 years, and 47% were male. The average LOS in 2012 was two days and had a decreasing trend to 1.2 days in 2020 (ß = -0.01, p < .001). Multivariate analysis revealed that increased LOS postoperatively was an independent predictor of increased total charges and costs of surgery after adjustment for covariates including overall health of the patient. Between 2012 and 2020, there was an observed increase in total costs despite accounting for the decrease in LOS. The total costs of surgery would have increased 11.8% ($18,597.03 to $20,792.84) from 2012 to 2020 if surgeons maintained the 2012 LOS; total costs would have increased 5.5% ($18,597.03 to $19,628.92) from 2012 to 2020. CONCLUSION: Total hospital costs for total shoulder replacement increased by 23% from 2012 to 2020. This increase in total cost was simultaneously dampened by the concurrent reduction in LOS, from 2 days to 1.2 days. By recognizing the tangible link between shorter lengths of stay and economic savings, healthcare institutions can make informed decisions that promote both fiscal responsibility and quality patient care.Level of Evidence:: 3.