Association Between Minimally Invasive Osteotomy Techniques and Bunion Correction Outcomes

Background: Minimally invasive surgery (MIS) for hallux valgus (HAV) correction may benefit from using the medial eminence to enhance lateral capital fragment translation. This study investigates whether osteotomy placement through the medial eminence correlates with improved HAV and forefoot width (FW) correction. A retrospective analysis of 20 patients who underwent MIS bunion correction was performed. Pre- and postoperative radiographs were reviewed to assess hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), sesamoid position, osteotomy location, osteotomy angle, capital fragment shift, and forefoot width. Pearson correlation and multivariable linear regression were used to identify associations. Chart review was performed at the one-year mark for complications (recurrence, infection, non-union, hardware failure). Significant correlations were found between DMAA and HVA (r = 0.883, p < 0.001), DMAA and IMA (r = 0.573, p = 0.008), and HVA and capital fragment shift (r = 0.541, p = 0.014). Osteotomy location and angle were not significantly associated with correction. Multivariable analysis showed DMAA was independently associated with HVA correction (β = 0.679, p < 0.001), and both capital fragment shift and metatarsal head angulation were associated with FW narrowing. Additionally, no patients in this cohort experienced complications. Use of the medial eminence in MIS osteotomy was not associated with improved HAV or FW correction. Angular deformity parameters and lateral fragment shift were more predictive of radiographic outcomes.