tetramelic monodactyly (Monarch Disease Ontology id MONDO_0008544) is a rare, genetic, congenital limb malformation disorder characterized by the presence of a single digit on all four extremities. Malformation is typically isolated however, aplastic and hypoplastic defects in the remaining skeletal parts of hands and feet have been reported. There have been no further descriptions in the literature since 1992. Also known as: Sommer-Hines syndrome.