A Classification of Polydactyly and Its Application to The Treatment

Baek, Goo Hyun; Chung, Moon Sang; Kim, Dong Jun

Abstract

Polydactyly is one of the most common congenital anomalies of the limb, however its surgical treatment varies from simple excision to reconstruction. The purpose of this study is to present out classification of polydactyly in which the type of surgery was concerned primarily. Two hundred and thirty five digits(134 fingers and 101 toes) in 188 patients were operated from 1980 to 1992. We divided the polydactyly into two types-the simple type, in which the extradigit arises from only one digit, and the complex type in which the extradigit connects more than two adjacent main digits. The simple type was subdivided into joint type(type I), in that the extradigit has its own joint in its origine; epiphyseal type(type II), the extradigit share common epiphysis with main digit; and hypoplastic type(type III), the extradigit is connected only by soft tissue to the main digit. The epiphyseal type(type II) was further divided into subtype A(type IIA), in that the origin seems to be directly derived from the epiphysis; and subtype B(type IIB), which resemble an osteochondroma. Type III and type IIB can be treated by simple excision, however the type I and type IIB can be treated by arthroplasty with or without osteotomy as well as excision of extradigit. Result of surgical treatment in 1 digit of the simple form, which siginifies the extradigit arising from only one digit, are good in 193 digits(91%), fair 14(6.6%), and poor 5(2.4%) after an average follow-up period of 20 months. Our principles in the surgical treatment of polydactyly was treatment according to the type, and early treatment.