Polydactyly has been classified by Wassell into 7 different types based on bony differentiation.
Type I: Bifid distal phalanx
Type II: Duplicated distal phalanx
Type III: Bifid proximal phalanx
Type IV: Duplicated proximal phalanx [Most Common]
Type V: Bifid Metacarpal
Type VI: Duplicated metacarpal
Type VII: Triphalangism
See also: Congenital anomalies of hand (Classification)
See also: Hand and Wrist Examination
