Trends in Geographic Utilization of Total Ankle Arthroplasty and Ankle Arthrodesis

Abstract

Category: Ankle Arthritis Introduction/Purpose: Total ankle arthroplasty (TAA) and ankle arthrodesis (AA) are common surgical treatment options for end-stage ankle arthritis. Previous studies of trends in TAA utilization have shown a rapid increase in use from 2000-2010, likely due to improvements in implants and surgical techniques. The purpose of this study is to assess relative rates of TAA and AA utilization, investigate these trends in across populations and hospital settings, and project these trends in 2030. Methods: The National Inpatient Sample database was queried from 2016-2019 using International Classification of Diseases codes for TAA and AA to identify 8,787 patients (TAA=4,664, AA=4,123). Patient information collected included age, sex, race, primary payer status, year of surgery, length of hospital stay, and median household income quartile. The latter was determined by the NIS database using patient zip code, with the first quartile being the poorest and fourth quartile the richest. Hospital information included bed size, census region, teaching status, and ownership. Results: The ratio of TAA to AA increased from 0.90 in 2016 to 1.33 in 2019. Compared to AA patients, TAA patients were more significantly likely to be male (p=.004), white (p <.001), older (p <.001), and have higher income (p <.001). TAA was more likely to be performed over AA at hospitals which were either smaller (p <.001), urban non-teaching (p <.001), in the western U.S. (p <.001) or with a private, for-profit ownership structure (p=.002). The overall highest volume of both TAAs and AAs were performed in large (TAA=45.6%, AA=55.6%), southern (TAA=31.5%, AA=34.9%), urban-teaching (TAA=75.9%, AA=78.9%) hospitals with private, non-profit ownership (TAA=75.8%, AA=75.0%). TAA utilization is estimated to increase by 79.5% and AA to decline by 63.8%. (Table 1) Conclusion: TAA has continued to grow in utilization from 2016-2019 and is projected to continue this growth to 2030, while AA is expected to decrease in use. Furthermore, patients more likely to receive a TAA than AA are disproportionally white, male, and have a higher income and hospitals more likely to preform TAA are small, urban, for-profit hospitals in the western United States.