Triphalangeal thumb - polysyndactyly syndrome (Orphanet rare-disease nomenclature term Orphanet_2950) can be described as follows. Triphalangeal thumb-polysyndactyly syndrome (TPT-PS) is a hand-foot malformation characterized by triphalangeal thumbs and pre- and postaxial polydactyly, isolated syndactyly or complex polysyndactyly. Also known as: TPT-PS syndrome.