The true triplication of the thumb: a case of unclassified thumb polydactyly.

A child with true triplication of the thumb is reported. Each thumb has a well-developed metacarpal, and one of them is biphalangeal; the remaining 2 are triphalangeal. Satisfactory result was obtained from a functional and esthetic point of view. Our surgical approach to this interesting anomaly and the necessity of a new group under the Wassel classification for the categorization of different forms of thumb triplications is discussed.