Size and shape differences between male and female foot bones: is the female foot predisposed to hallux abducto valgus deformity?

This study introduces a new technique to measure bone size and shape. A three-dimensional laser scan was taken of the talus, navicular, medial cuneiform, and first metatarsal from 107 skeletons of known age and sex. The bones were analyzed for differences in bone morphology between the sexes and the ability of each bone to contribute to the adducted position of the first metatarsal. Linear measurements showed that male bones were larger than female bones. Measurements of articular surfaces suggested that female bones had the potential for more movement to occur in the direction of adduction, possibly resulting in the female first metatarsal being more adducted than that in the male skeleton. Such differences may underlie the predisposition of the female foot to develop hallux valgus deformity.