Does the Learning Curve of Minimally Invasive Chevron and Akin Osteotomies Affect Outcome of Hallux Valgus Correction?

Abstract

Category: Bunion Introduction/Purpose: Minimally invasive chevron and akin osteotomy (MICA) has become increasingly popular in the correction of hallux valgus deformity. This study compared the radiological outcomes of the first cases performed by 2 surgeons using this technique with open scarf and akin osteotomy Methods: A retrospective review of hallux valgus corrections performed in Northumbria Healthcare NHS Trust between March and September 2014. Consecutive patients who underwent MICA correction by 2 surgeons trained on a cadaveric course were compared with a group of patients with mild to moderate deformity that underwent open scarf correction. Pre and post radiographic assessment was performed measuring the hallux valgus angle (HVA), the intermetatarsal angle (IMA) and medial sesamoid position (MTS) using Hardy and Clapham classification. Radiographic measurements where statistically compared for difference and complications were recorded. Results: 14 MICA procedures were identified and compared with 14 scarf procedures. Average age of the MICA group was 46 vs. 55 for the scarf group. Pre operative radiographic measurements showed no statistical difference between MICA vs. scarf: Mean HVA 26.9 vs. 28.2 degrees (p 0.698), mean IMA 14.7 vs. 15.3 degrees (p 0.512) and mean MTS grade 5 vs. 5.5 (p 0.251). Change in these parameters between MICA vs. scarf also did not show any statistical difference: Mean HVA change 17.2 vs. 19.2 degrees (p 0.396), mean IMA change 8.5 vs. 8.1 degrees (p 0.680) and mean MTS grade change 2.6 vs.3.2 (p 0.149). In the MICA group, 1 procedure was converted to open and post operatively 1 screw was removed due to length. In the scarf group 1 patient developed a superficial infection that resolved with antibiotics and 1 prominent screw for akin osteotomy required removal. Conclusion: Early experience of MICA resulted in similar outcomes and complications compared with open scarf and akin osteotomy.