[Hereditary symphalangism: observations on this syndrome in a newborn infant and his mother (author's transl)].

Symphalangism is the partial or complete bony fusion of phalanges in the fingers and toes due to an autosomal dominant gene, with inherited failure of development of one or more interphalangeal joints. Two patients--a newborn baby and his mother--both revealing this rare malformation, are presented in this paper and the clinical and radiological features are described and discussed.