Long-Term Follow-up of Capsular Interposition Arthroplasty for Hallux Rigidus

Background: Capsular interposition arthroplasty is a joint- and motion-sparing procedure that has been shown as an effective alternative to fusion. This study aimed to evaluate patient function and satisfaction after long-term follow-up. Methods: Sixty-four patients were treated with capsular interposition arthroplasty for hallux rigidus by the senior author performed between February 1998 and July 2011. Twenty-two patients could not be reached for follow-up and were thus excluded from the analysis. Therefore, 42 remaining patients were evaluated using the visual analog scale (VAS), Foot Function Index (FFI), Short Form 12 (SF-12), and patient satisfaction scores. The mean follow-up was 11.3 (range, 4-16) years. Results: The mean VAS for pain was 7.9 preoperatively and 1.8 postoperatively (P = .003). The mean preoperative SF-12 physical score was 42.0 vs 64.2 postoperatively (P = .02). The mean preoperative SF-12 mental score was 50.7, while the postoperative SF-12 mental score was 54.6 (P = .01). The total FFI score also significantly improved, with a preoperative value of 98.3 and a postoperative mean score of 49.6 (P = .001). The mean patient satisfaction score was 7.4 of 10. Overall, 39 of 42 patients (92.9%) stated they would have the surgery again. Four of the 42 patients (9.5%) required conversion to hallux metatarsophalangeal fusion at a mean of 6.1 years after the index procedure secondary to pain, but no other complications were reported. Conclusion: Capsular interposition arthroplasty was a safe and effective treatment for severe hallux rigidus. These longer term results demonstrate a high level of patient satisfaction. Level of Evidence: Level IV, retrospective case series.