Influence of Postoperative Tibial Sesamoid Position on the Outcomes of Minimally Invasive Transverse Osteotomy (MITO) for Hallux Valgus Correction

Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: Postoperative tibial sesamoid position (TSP) is one of the controversial issues in the recurrence after hallux valgus correction, however, analyses of its influence on the outcomes after minimally invasive hallux valgus correction remain limited. This study evaluated the influence of the postoperative TSP on the outcomes after minimally invasive transverse osteotomy (MITO) for hallux valgus correction. Methods: Between July 2018 and August 2022, 118 patients underwent MITO and followed for at least 24 months. Total 165 feet were included in this study, and were allocated into two groups based on Hardy and Clapham’s classification (normal group: grades I-III, outlier group: grades IV-VIII), recorded on postoperative 6-month weight-bearing anteroposterior radiographs. Clinical outcomes were assessed using the visual analog scale for pain, the Foot and Ankle Outcome Score, and the Medical Outcomes Study Short Form Health Survey-36 physical component summary. Hallux valgus angle (HVA), first-to-second intermetatarsal angle (1-2 IMA), TSP were measured for radiologic evaluation. Recurrence and complications were also analyzed. Results: A total of 165 feet (normal group; 121 feet, outlier group; 44 feet) were included in this study and mean follow-up period was 35.6 months (range, 24-70 months). Outlier group showed significantly higher HVA, 1-2 IMA and TSP at preoperative, postoperative 6-month and last follow-up compared to the normal group (all P< 0.001). The increase of HVA between postoperative 6-month and last follow-up was significantly greater in the outlier group (P < 0.001). Both groups showed significant improvement of all functional scores without significant differences between the groups, however, recurrence rate (P < 0.001) and reoperation rate (P=0.013) were significantly higher in the outlier group. Conclusion: Postoperative TSP in anteroposterior standing radiographs was associated with hallux valgus recurrence after minimally invasive correction surgery. Precise correction of TSP may be helpful to prevent the recurrence of hallux valgus.