Severity of flatfoot and hallux valgus deformities: Is there a correlation?

Introduction: Hallux Valgus (HV) is a dynamic foot deformity. The biomechanical factors are not completely understood. Recently, a relation between medial foot arch collapse, with subsequent foot pronation and excessive pressure on the first metatarsophalangeal joint, and HV deformity has been investigated. Therefore, in this study we aim establish a relation between the severity of HV and flatfoot deformities.

Methods: We retrospectively reviewed the preoperative upright foot radiographs of patients submitted to HV surgical correction and measured the Intermetatarsal (IM), HV, Meary’s and Medial Arch (MA) angles. Re-intervention cases were excluded.

Results: 131 feet from 120 patients were evaluated. There was a moderate, positive correlation between IM and Lateral Meary’s angles and also between IM and MA angles. As expected, IM and HV angles were strongly correlated, as were MA and Lateral Meary’s angles. In addition, flatfoot prevalence varied significantly according to HV severity.

Discussion: There isn’t a clear consensus on this matter in current literature. The authors did not find strong recommendations in favour of treating both deformities simultaneously in order to prevent progression or recurrence of any of them. Standard weight bearing radiographs are important to achieve a global foot evaluation and diagnose associated deformities and to establish an adequate surgical strategy.

Conclusion: Our findings support a moderate association between the severity of HV and flatfoot deformities. Regarding treatment strategies, larger biomechanical and clinical randomized controlled studies are needed to establish more reliable conclusions.