Comparison of Radiographic and Clinical Outcomes between Distal and Proximal Minimally Invasive Chevron and Akin Osteotomy for Severe Hallux Valgus Deformity

Abstract

Category: Midfoot/Forefoot; Midfoot/Forefoot Introduction/Purpose: The surgical treatment of severe hallux valgus (HV) deformity is challenging due to the difficulty in achieving sufficient reduction and the increased risk of complications such as recurrence, delayed or non-union. Minimally invasive surgery (MIS) has been increasingly used to treat HV deformity, with the third-generation minimally invasive Chevron and Akin osteotomies (MICA) technique being widely accepted. This retrospective cohort study aimed to compare the radiographic and clinical outcomes between the distal and proximal MICA techniques for severe hallux valgus deformity. It was hypothesized that the proximal MICA technique would provide better radiographic results due to the stronger deformity correction achieved by the proximal metatarsal osteotomy. Methods: Seventy-four feet with severe HV (defined as HVA [≥40 degrees] and/or IMA [≥20 degrees]) treated with distal MICA (40 feet) or proximal MICA (34 feet) were included in this study after at least one year of follow-up. Clinical assessment included the American Orthopaedic Foot & Ankle Society (AOFAS) score, pain visual analog scale (VAS), patient satisfaction rating, and complications. Radiographic assessments included HV angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA). Results: There were no differences in the mean AOFAS score, pain VAS score, and patient satisfaction rate at the final follow-up between the two groups (all p > .05). The mean postoperative HVA, IMA, and DMAA significantly improved at the final follow-up in both groups (all p < .001). There was no significant difference in the improvement of radiographic values after surgery between the two groups (all p > 0.05). Although not statistically significant, there was a trend toward a higher recurrence and delayed or nonunion rate in the distal MICA group (7.5% vs. 2.9%, P =.218 and 10% vs. 2.9%, P =.072). Conclusion: Both types of minimally invasive techniques resulted in satisfactory outcomes in terms of significant improvement in clinical values, large deformity correction, and reasonable complication rates. However, the proximal MICA technique appears to provide more stable maintenance of deformity correction than the distal technique.