Incidence of Polydactyly and Triphalangism of Thumb

ABSTRACT

PURPOSE: Preaxial polydactyly is the most common congenital anomaly of upper extremities. In this study, we classified 112 patients of preaxial polydactyly for investigation of recent incidences of each types. METHODS: We reviewed 120 cases of preaxial polydactyly diagnosed at university hospitals of Incheon and Bucheon from 2000 to 2008. All cases were grouped using simple radiographs and all cases were classified according to the Upton modified Iowa system. RESULTS: Among the 120 cases of preaxial polydactyly, 7 cases(6%) were in type I polydactyly, 35 cases(29%) type II, 1 case(1%) type III, 48 cases(40%) type IV, 12 cases(10%) type V, 5 cases(4%) type VI, 12 cases(10%) type VII, respectively. All cases in type VII polydactyly were triphalangism. CONCLUSION: Comparing with Wassel's study and Upton's study, our study showed similar distribution of each types of preaxial polydactyly.