Absent tibiae, triphalangeal thumbs and polydactyly: description of a family and prenatal diagnosis.

A family with absent tibiae, triphalangeal thumbs and polydactyly is described. Bilateral absence of tibiae is the most severe manifestation of this syndrome. The pedigree of this family suggests an autosomal dominant inheritance with variable expression. Prenatal diagnosis was made at 20.5 weeks of pregnancy. Fetal radiographs showed the presence of both tibiae; this finding was confirmed at birth.