Minimally Invasive Surgery for Severe Hallux Valgus with 2 Year Minimum Follow Up in 106 Feet

CATEGORY: Bunion; Lesser Toes; Midfoot/Forefoot INTRODUCTION/PURPOSE: There is widespread variation in the optimal procedure for correction of severe hallux valgus deformity. Severe hallux valgus (defined as hallux valgus angle (HVA) (>=40°) and/or 1-2 intermetatarsal angle (IMA) (>=20°)) is associated with increased complication rates including recurrence, delayed or non-union and metatarsal shortening with transfer metatarsalgia. There is limited evidence investigating the clinical or radiological outcomes following treatment of severe hallux valgus deformity with third-generation minimally invasive chevron and akin osteotomies (MICA). Objective: The primary aim was to investigate clinical patient reported outcome measures (PROMs) two years following surgery and the radiographic deformity correction for patients undergoing third-generation MICA for severe hallux valgus deformity. METHODS: Prospective observational single surgeon series of consecutive patients who underwent primary third-generation MICA with screw fixation for severe hallux valgus. The primary outcome was a validated patient reported outcome measure, the Manchester-Oxford Foot Questionnaire (MOXFQ), assessed minimum 2 years following MICA. Secondary outcomes were radiographic deformity correction, complication rates and other quality of life PROMs (EQ-5D and Visual Analogue Pain Scale). RESULTS: Between September 2014 and May 2018, 106 consecutive feet (n=78 patients; 73 female, 5 male) met the inclusion criteria. Prospectively collected pre-operative and 2 year PROM MOXFQ data was available for 86 feet (81.1%). At two years following surgery, the MOXFQ score significantly improved for the Pain, Walking and Standing and Social Interaction domains from 39.2 to 7.5, 38.2 to 5.9 and 48.6 to 5.5, respectively (p<0.001). Pre- and post-operative radiographic data was available for all 106 feet. Mean IMA following surgery improved from 18.2° to 6.3° (p<0.001) whilst mean HVA improved from 45.3° to 10.9° (p<0.001). CONCLUSION: This study has demonstrated third-generation MICA for the treatment of severe hallux valgus deformity can achieve significant improvements in clinical PROMs and radiographic deformity correction.