Increasing utilization of total ankle arthroplasty in Japan: Trends and regional variations over 12 Years from a national database.

Background: Ankle arthritis significantly impacts a patient's quality of life, often necessitating surgical treatment in advanced cases. While ankle arthrodesis has been the standard procedure for decades, total ankle arthroplasty (TAA) has gained acceptance as a motion-preserving alternative. Although TAA adoption has expanded globally, data on trends and regional variations in Japan are limited. This study aimed to analyze the utilization and regional disparities in TAA and ankle arthrodesis over a 12-year period using a national database.

Methods: Data were retrospectively extracted from the Diagnosis Procedure Combination database, which includes over 50 % of inpatient admissions in Japan. Patients who underwent primary TAA or ankle arthrodesis for osteoarthritis or rheumatoid arthritis between 2010 and 2022 were included. Procedure counts, patient demographics, and regional variations were analyzed. Statistical methods included linear regression for trend analyses and exploration of factors influencing regional disparities, such as hospital volume and the number of members of the Japanese Society for Surgery of the Foot.

Results: From 2010 to 2022, 2461 TAA and 9415 ankle arthrodesis procedures were performed. TAA utilization increased 3.8-fold compared with a 1.4-fold increase in ankle arthrodesis. The proportion of TAA among ankle surgeries increased from 13.4 % to 30.2 %. TAA was performed more frequently in older patients and those with rheumatoid arthritis than ankle arthrodesis. Over the study period, the average age of TAA patients significantly increased, whereas the proportion of patients with rheumatoid arthritis decreased, reflecting a shift toward treating patients with osteoarthritis. Significant regional variations in TAA utilization were observed, primarily influenced by the availability of high-volume hospitals.

Conclusions: TAA utilization has grown significantly in Japan, underscoring its acceptance as an alternative to ankle arthrodesis. However, access disparities persist, driven by the limited availability of high-volume hospitals. These findings highlight the need for improved access to TAA and the standardization of surgical practices to ensure equal treatment opportunities for patients with ankle arthritis.