Hallux varus--a study of thirty cases.

Although both congenital and acquired hallux varus have been described, the deformity has been considered uncommon. Contrary to this belief, we noted that it is fairly common in the unshod population. Analysis of 30 cases shows that congenital hallux varus is the most common type encountered and it is of three types, namely: primary, secondary, and teratogenic. The congenital primary and secondary varieties are apparently easy to treat in infancy, but if left untreated, they progress with age in unshod persons. The more severe grades of hallux varus are associated with medial deviation of the lateral toes. Hallux varus occasionally develops in unshod persons during the fourth, fifth, or sixth decades of life. This is referred to as the idiopathic hallux varus of middle age. The length of the first metatarsal, the first intermetatarsal angle, and the shape of the first metatarsal head appear to have no bearing on the causation of hallux varus. The progression of the deformity in congenital cases and the de novo development of the deformity in middle age appear to be related to the failure to use footwear.