The Rise of Total Ankle Arthroplasty Use: A Database Analysis Describing Case Volumes and Incidence Trends in the United States Between 2009 and 2019

Background: Ankle arthrodesis has been the mainstay treatment for end-stage ankle arthritis. The popularity of total ankle arthroplasty (TAA) has been on the rise due to improved implant design and postoperative outcomes. The purpose of this study was to describe the basic epidemiology and trends of annual procedure volumes and incidence in the general American population as well as in different population subgroups from 2009 to 2019. We hypothesize that the incidence of TAA has significantly risen while the median length of hospital stay has decreased nationwide. Methods: The IBM MarketScan database was queried for patients who underwent TAA from January 2009 to December 2019 based on Current Procedural Terminology coding. Population estimates from the US Census Bureau were used to calculate the annual incidence of TAA. Procedural volume and incidence were calculated for annual sums, gender, age subgroups, inpatient and outpatient TAA, as well as in four statistical geographic regions in the United States. Median length of hospital stay was calculated and trended annually for inpatient TAA. Results: A total of 41,060 primary TAAs were identified in the database from 2009 to 2019, in which 52.5% were performed in males. Annual volumes increased by 136.1%, from 2180 to 5147 procedures nationwide. Incidence reported per 100 000 population increased by 120.8%. Both inpatient and outpatient procedures have increased, by 242.5% and 86.6%, respectively. Median length of hospital stay decreased from 3 days in 2009 to 1 day in 2019 and did not differ between genders. Growth in incidence was demonstrated in males and females above the age of 54 years with the largest growth in annual incidence found between 65 and 74 years. Incidence rose in the South and West of the United States by 111.8% and 136.5%, respectively. Conclusion: We found that annual volumes and incidence rates of primary TAA has increased between 2009 and 2019. Although both inpatient and outpatient surgery have become more frequent, inpatient volumes and incidence have increased almost 3 times more than those of outpatient surgery. Length of hospital stay decreased over the study years. When adjusted for the same study period, the cumulative annual growth rates of TAA were found to be 2 times greater than total knee arthroplasty and 3.6 times greater than total hip arthroplasty. Level of Evidence: Level III, retrospective database review.