Classification of polydactyly of the hands and fee

Abstract

The authors present a new classification of polydactyly based on radiomorphological alterations. The malformations are defined in two directions, as in a system of coordinates. The longitudinal arrangement is based on the pathogenetic principle of bifurcation of a finger or a toe ray from distal to proximal. We accordingly divided polydactylies into five types: distal phalanx, middle phalanx, proximal phalanx, metacarpal or metatarsal, carpal or tarsal. The transverse arrangement indicates which rays are involved. All polydactylies, including the special forms such as rudimentary manifestations, triphalangism, and multiple duplications, can be incorporated into this simple basic scheme. Depending on their characteristics, the special forms are further subdivided, e.g., into a distal or proximal phalanx type with simple or double triphalangism, or a tarsal type with third-degree duplication and first-degree aplasia. Numerous radiological examples and schematic drawings illustrate the classification. The advantage of the classification is that it depends exclusively upon the skeletal finding and all manifestations are registered according to a simple scheme longitudinally and transversely. This makes them codifiable for the computer and suitable for multicenter studies. The special forms, the rudiment, triphalangism, and multiple duplication, can easily be further subclassified. Moreover, the nomenclature is simple and is oriented to anatomical terminology.

New Classification of Polydactyly of the Foot on the Basis of Syndactylism, Axis Deviation and Metatarsal Extent of Extra-Digit

“…Many attempts to classify polydactyly of the foot have been described in past publications [1,[3][4][5][6][7][8][9][10]. Numerous authors, feeling the need for an organized overview, have attempted to devise a classification system for polydactyly of the foot.…”

“…The surgical methods are diverse, and the prognosis varies greatly. Nevertheless, classification of polydactyly of the foot has received little attention relative to that of the hand, although some authors have attempted to classify polydactyly of the foot in past publications [1,[3][4][5][6][7][8][9][10]. Their cases were usually classified by representative conventional systems used in hand polydactyly, such as the Wassel classifica-tion [11], Stelling and Turek's classification [12], and the Hirase classification [13].…”

Bilateral Thumb Polydactyly: Case Report

“…This congenital deformation pattern may be isolated or associated with other anomalies [1,4]. Polydactyly is usually classified into three major groups: medial ray (preaxial), central ray and lateral ray (postaxial) [9], thereby it's presented according to the Wassel's classification into seven types (Type I: bifid distal phalanx.…”

“…It can be isolated or associated with other abnormalities in several syndromes [4]. Different types of thumb polydactyly, classified by Wassel into 7 types according to the level of bifurcation, and the extent of the deformation [5].…”

Sporadic familial ulnar hexadactyly of all four limbs

“…According to the classification of polydactyly of hands and feet of Blauth and Olason (1988) our index case shows a proximal phalanx hexadactyly of the 5th digit of all four limbs. 12 To the best of our knowledge this is the first case description in multiple members of the same generation in a single family.…”