Preoperative increased pronation angle of the first metatarsus associated with correction loss after hallux valgus surgery: A semi-weight-bearing computed tomography study.

ABSTRACT

BACKGROUND: The effect of preoperative first metatarsal pronation on postoperative prognosis of hallux valgus (HV) surgery is under investigation. Utilizing semi-weight-bearing computed tomography, the preoperative pronation angle was assessed to quantify its impact on postoperative prognosis. METHODS: In a retrospective analysis of 31 feet, those with re-increased hallux valgus angle postoperatively were classified as the non-maintained group, and the remainder as the maintained group. Preoperative pronation angles were compared to establish a threshold. Subsequently, feet were re-classified into high or low-pronation categories. The relative risk of non-maintenance in high-pronation category was calculated. RESULTS: The non-maintained group exhibited a significantly higher preoperative pronation angle (p = 0.021), with a 28.4º threshold. The high-pronation category had a relative risk of 2.34 for non-maintenance. CONCLUSIONS: Increased preoperative first metatarsal pronation angle is associated with correction loss after HV surgery. Utilizing sWBCT to measure the pronation angle provides valuable insights into postoperative prognosis. LEVEL OF EVIDENCE III.