Quarterly Trends in Total Knee Arthroplasty Utilization in the United States: Insurance Cost Sharing Drives Seasonal Variation.

Abstract

Amid total knee arthroplasty (TKA) expansion and shrinking reimbursements, optimization is a priority. Out-of-pocket cost sharing has been shown to influence elective surgery scheduling, however, utilization patterns have yet to be demonstrated in TKA. The purpose of this study was to evaluate the relationship between insurance cost-sharing and TKA utilization. A retrospective observational cohort study was conducted using a large database. Patients who had a diagnosis of knee osteoarthritis between January 1, 2018, and December 31, 2023, were included. The percentage of primary TKA procedures performed in this population during each calendar month and quarter was calculated. Patient payment contribution was compared across insurance plan types, and the association between payment and utilization was evaluated. A total of 450,125 patients received a diagnosis of knee osteoarthritis. Overall TKA utilization was 11.1, 11, and 10% among high-, average-, and low-costing sharing groups, respectively. Average- and low-cost-sharing groups had significantly higher utilization in Q1 compared to the high-cost-sharing group (High versus Average: 19.9 versus 22.7%, P < 0.001; High versus Low: 19.9 versus 23.1%, P = 0.007). The high-cost-sharing group had a significantly higher utilization in Q4 compared to the average and low groups (High versus Average: 35.7 versus 30.8%, P < 0.001; High versus Low: 35.7 versus 29.6%, P < 0.001). During Q1, high-, average-, and low-cost-sharing patient payment contributions averaged $1,761.5, $886.7, and $356.5, respectively. Pearson correlation testing demonstrated an inverse relationship between out-of-pocket cost and surgical volume, with higher patient payments significantly associated with lower TKA utilization (Pearson r = -0.42, P < 0.001). Across all insurance groups, there was a significant inverse correlation between patient payment and quarterly percent utilization, revealing periods of low utilization in Q1 and high in Q4. By anticipating periods of low demand and accommodating high-demand periods, hospital systems and surgeons can better maximize efficiency.