One Year Follow-Up of Patient Reported Outcomes Following Third Generation Minimally Invasive Chevron Akin Osteotomies (MICA) in Hallux Valgus Surgery

CATEGORY: Bunion INTRODUCTION/PURPOSE: The aim of this study was to explore the short-term results of third generation (using screw fixation) Minimally Invasive Chevron and Akin osteotomies (MICA) for hallux valgus correction. There is a paucity of published data regarding the outcomes of this relatively new technique. We present the largest series in the literature, using three separate validated patient-reported outcome measures (EQ-5DL, VAS Pain and Manchester Oxford Foot Questionnaire (MOXFQ), for this time point. METHODS: A single surgeon case series of patients with hallux valgus underwent primary third generation minimally invasive chevron and akin osteotomies (MICA) for hallux valgus correction. Between August 2015 and January 2019, 430 MICAs were performed in 295 patients that were eligible for 1 year follow up. Baseline and 1 year post-operative patient reported outcomes were collected for 242 feet in 194 patients (182 females; 12 males). Paired t-tests were used to determine the statistical significance of the difference between pre- and post-operative scores. RESULTS: The mean age was 55.9 (range 16.3-84.9, standard deviation (s.d.) 12.5). At one year follow up, the mean MOXFQ scores had improved for each domain: Pain; baseline 41.9 (range 0-100, s.d. 21.8), reduced to 13.8 (range 0-90, s.d. 17.7, p<0.001); Walking; baseline 34.6 (range 0-100, s.d. 24.3) reduced to 9.8 (range 0-89.0, s.d. 18.0, p<0.001); Social interaction; baseline 45.4 (range 0-100, s.d. 22.8), reduced to 8.2 (range 0-75.0, s.d. 14.7, p<0.001). Mean VAS Pain score improved from 29.8 (range 0.0-90.0, s.d. 22.1) to 8.2 (range 0.00-64.0, s.d. 12.8, p<0.001). Mean EQ-5D index score improved from 0.755 (range 0.066-1.000, s.d. 0.136) to 0.891 (range 0.350-1.000, s.d. 0.124, p<0.001). Mean EQ-5D VAS score improved from 83.4 (range 28- 100, s.d. 12.4) to 85.6 (range 0-100, s.d. 14.2, p=0.047). CONCLUSION: This is the largest prospective case series of short-term patient reported outcomes using a validated assessment method for hallux valgus, following third generation MICA to date. These data show that this technique is effective at improving foot and ankle specific patient reported outcomes at 1 year. This cohort is being followed over the longer term.