Metatarsal Pronation: Does It Matter?

Category: Bunion Introduction/Purpose: Hallux Valgus is a complex deformity with several attendant components that are present to varying degrees in each patient. Historically primary attention has been paid to correction of the coronal plane deformity, but recent investigations suggest a substantial contribution to the deformity from the axial rotational abnormality of the metatarsal. While the effect of this metatarsal pronation has been demonstrated, the relative contribution of this parameter compared to other components has not been considered. This study aims to investigate the rotational aspect of the deformity and its contribution to successful radiographic correction of the deformity. Methods: A retrospective review of 100 consecutive Lapidus bunionectomy procedures was performed. There were 80 of patients and 89 feet. patients Results: The average HVA correction was 20.08 degrees and 6.86 degrees for IMA. A total of 68 feet had a positive preop round head sign and correction to a normal MT head shape was observed in 47 feet. A significant increase in recurrence was associated with patients that had persistent MT round sign following correction (p=0.001) and in patients with a higher sesamoid position in the preop period pConclusion: Adequate preoperative radiographic assessment is of the utmost importance to assess the various forces that can contribute to hallux valgus deformity. Newer techniques address coronal and sagittal plane deformity. Failure to correct MT head pronation may lead to increased hallux valgus recurrence, despite sagittal correction measured by improvement of the HVA and IMA angles. Factors that impact time to fusion are also associated with a higher risk of HV recurrence. Sesamoid position and metatarsal head pronation should be considered, and correction of these parameters may be necessary to avoid delayed healing and persistent or recurrent HV.