Congenital hand anomalies in Japan: a family study.

During the 20-year period from 1968 to 1987, 1024 patients with congenital anomalies of the hand from 1000 Japanese families were examined in our clinic. Of these patients, 204 had relatives with limb anomalies. While postaxial polydactyly showed a 33% level of familial recurrence, symphalangism and Kirner's syndrome showed about 23% recurrence, syndactyly 18%, radioulnar synostosis 9%, radial ray deficiency 8%, cleft hand 7%, and duplicated thumb 5%. None of the relatives had ulnar deficiency or symbrachydactyly.