Congenital familial hypoplastic thumb associated with congenital amputation of the toe.

A family with congenital hypoplastic thumb ( Blouth type 1) associated with congenital amputation of the first toe is reported. An 18-year-old woman and her mother had the same congenital anomalies: hypoplastic thenar muscles, congenital amputation of the first toe, slight web formation between second and third toes, and brachymesophalangia 2 and 5. There were no associated cardiovascular defects. They have a characteristic metacarpophalangeal pattern profile. This is believed to be the first such case report in the medical literature.