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.

Keywords: Correction loss; First metatarsal pronation; Hallux valgus; Weight-bearing computed tomography.