One-Month Postoperative Tibial Sesamoid Position Predicts Recurrence After Minimally Invasive Hallux Valgus Correction: A Retrospective Cohort Study.

Abstract

The role of postoperative tibial sesamoid position (TSP) in hallux valgus (HV) recurrence remains controversial, and studies on its impact after third-generation minimally invasive HV surgery are limited. This study analyzed the association between postoperative TSP and outcomes after minimally invasive transverse distal metatarsal osteotomy (MITO) for HV correction. This retrospective cohort study included 118 patients who underwent MITO between July 2018 and August 2022 with ≥24 months of follow-up. Patients were grouped by 1-month postoperative TSP based on Hardy and Clapham classification (grades I-III: normal; grades IV-VII: outlier). Clinical outcomes were assessed using visual analog scale pain scores, Foot and Ankle Outcome Scores, and Medical Outcomes Study Short Form Health Survey-36 physical component summary scores. Radiologic evaluation included hallux valgus angle (HVA), first-to-second intermetatarsal angle (1-2 IMA), and TSP measurements. Recurrence and complications were also analyzed. This study analyzed 165 feet (normal: 122 feet; outlier: 43 feet) with a mean follow-up of 35.6 months (range, 24-70 months). The outlier group showed consistently greater HVA (43.8 degrees vs 32.7 degrees preoperatively; 8.7 degrees vs 4.8 degrees at 1 month; 12.8 degrees vs 5.1 degrees at last follow-up), 1-2 IMA (15.6 degrees vs 13.0 degrees preoperatively; 5.7 degrees vs 3.7 degrees at 1 month; 6.6 degrees vs 4.5 degrees at last follow-up), and TSP (7 vs 6 preoperatively; 4 vs 2 at 1 month; 5 vs 2 at last follow-up) at all time points (all <i>P</i> < .001), with greater HVA increase from 1 month postoperatively to last follow-up (<i>P</i> < .001). Functional scores improved similarly in both groups. On multivariable analysis, an outlier TSP at 1 month independently predicted recurrence (adjusted odds ratio 13.24, 95% CI 3.40-51.58), with good discrimination (area under the curve 0.838). Recurrence (<i>P</i> < .001) and reoperation rates for symptomatic recurrence (<i>P</i> = .017) were significantly higher in the outlier group. Postoperative TSP on anteroposterior standing radiographs at 1 month after surgery was associated with HV recurrence after MITO surgery. Precise correction of TSP may be essential to reduce the likelihood of HV recurrence.