ICD-11 definition : Polysyndactyly is a form of preaxial polydactyly of fingers characterized by the presence
of a thumb showing the mildest degree of duplication, being broad, bifid or with radially
deviated distal phalanx. Syndactyly of various degrees of third-and-fourth fingers
is occasionally present. Two forms have been characterized: unilateral and bilateral.;
ICD-11 synonym : syndactyly of multiple and unspecified sites; polysyndactyly syndrome; syndactyly of multiple digits;
Polysyndactyly is a form of preaxial polydactyly of fingers characterized by the presence
of a thumb showing the mildest degree of duplication, being broad, bifid or with radially
deviated distal phalanx. Syndactyly of various degrees of third-and-fourth fingers
is occasionally present. Two forms have been characterized: unilateral and bilateral.