Polydactyly of the hands and feet.

Polydactyly of the hand, of the foot, and of the hand combined with the foot were studied. As noted in previous reports of polydactyly, inherited cases represent about 10% of polydactyly of the hand or foot, and unilateral involvement is more common than bilateral. In 495 cases of polydactyly 27 patients had polydactyly of the hands and feet. The extra digits in 21 of those 27 were in the same digital rays of the hand and foot. There were 14 inherited cases (51.9%) and most were an autosomal dominant, but some were an autosomal recessive. Both hand and/or feet were involved in 22 cases. Most cases of preaxial polydactyly of the hand combined with central polydactyly of the foot were sporadic and unilateral. All cases of both preaxial and postaxial (polyaxial) polydactyly were inherited and bilateral. Two pairs of sisters had the same clinical features. The parent (mother or father) also had the same deformities in the inherited cases.