Distal symphalangism associated with camptodactyly.

A Japanese family in which four patients in three generations had distal symphalangism associated with camptodactyly is reported. All of these patients had extension limitation of the proximal interphalangeal joints of the toes of both feet. Radiographs of the hands and feet, undertaken in three cases, showed no bone fusion of the distal and proximal interphalangeal joints. This malformation is caused by an autosomal dominant gene. To our knowledge, no previous case of distal symphalangism with extension limitation of the proximal interphalangeal joints has been reported.