Relationship Between Hallux Valgus and Pes Planus: Real or Fiction?

Hallux valgus is one of the most common and painful deformities, occurring due to adductor/abductor imbalance of the big toe. Many structural foot disorders have been suggested as the cause of hallux valgus deformity. In this study, we aimed to show the relationship between hallux valgus and pes planus in adult males. A total of 213 patients were included in this study between May 2013 and May 2014. 54 patients with hallux valgus angle (HVA) >20° and intermetatarsal angle (IMA) >9° were evaluated in the case group and 159 patients randomly selected from those admitted for a recent foot ankle trauma with the HVA <15° and IMA <9° were the control group. All patients' HVA, IMA, and talonavicular coverage angle on anteroposterior (AP) foot radiographs and talar-first metatarsal angle (Meary's angle), calcaneal pitch angle, and lateral talocalcaneal angle on lateral foot radiographs were measured. There was no significant difference in talonavicular and Meary's angles between the groups. Calcaneal pitch angle was significantly lower in the case group, whereas talonavicular angle was higher in the control group. Calcaneal pitch angle and lateral talocalcaneal angle showed significant negative correlation with HVA and IMA. There are few reports in the literature about the relationship between pes planus and hallux valgus. Our results strongly showed a high correlation between pes planus and hallux valgus. Further larger patient cohort studies are needed to support our results.