Outcome comparison of minimally invasive proximal and distal chevron Akin osteotomies in patients with severe hallux valgus deformity: A randomized prospective study.

Abstract

To date, the surgical treatment of severe hallux valgus deformity remains challenging despite the various methods presented. This study aimed to compare the effectiveness of minimally invasive distal chevron Akin osteotomies (d-MICA) and minimally invasive proximal chevron Akin osteotomies (p-MICA) in correcting severe hallux valgus deformities. This prospective follow-up study included patients randomly assigned to undergo p-MICA or d-MICA for hallux valgus deformities with a preoperative hallux valgus angle (HVA) ≥ 40° and/or a first to second intermetatarsal angle (IMA) ≥ 16°. After a minimum follow-up period of twoyears, we compared various clinico-radiographic parameters of patients whose HVA exceeded 15° at the final follow-up. In the p-MICA and d-MICA groups, seven of 40 cases (17.5%) and 16 of 41 cases (39.0%), respectively, exhibited HVA > 15° at the final follow-up (P = 0.048). The preoperative parameters showed no significant differences. However, at the first weight-bearing assessment, the HVA, IMA, and relative second metatarsal length were significantly smaller, and the distal metatarsal articular angle (DMAA) was greater in the p-MICA group (all P < 0.05) compared with the d-MICA group. Postoperatively, both groups exhibited significant decreases in HVA and IMA at the final follow-up (P < 0.001 for all parameters). The p-MICA group showed no significant changes in DMAA and the relative length of the second metatarsal (P = 0.253 and 0.185, respectively). However, the d-MICA group showed a significant decrease in DMAA (P < 0.001) and an increase in the relative length of the second metatarsal at the final follow-up (P = 0.01). p-MICA and d-MICA procedures demonstrated effective correction potential for severe hallux valgus deformities; however, the d-MICA procedure exhibited a notably higher incidence of unsatisfactory correction at the final follow-up than p-MICA. Therefore, d-MICA may be less predictable in achieving successful outcomes than p-MICA in treating severe hallux valgus deformities.