title: Anatomical study of preaxial polydactyly in 158 hands.
abstract: Preaxial polydactyly is a common congenital hand anomaly. Here in 138 patients with 158 duplicated thumbs, a new classification of this anomaly was done from analysis of radiographs and operation records. Initially all the duplicated thumbs were arranged into from Type I to VII on the basis of radiological extent of bifurcation. Appendage type was noted as a separate entity. Type IV was found the most common and had 53 thumbs (33.6%) involved. But findings on surgery indicated that the exact level of bifurcation varied in each type, and Type VII became three times as frequent as previously noted from x-ray examination at the time of surgery. Radiologically encountered duplications at IP (Type II), MP (Type IV) and CM (Type VI) joints were specifically classified into five groups from A to E on the basis of the structural changes detected on surgery. Details in each group were discussed.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Tohoku University School of Medicine, Sendai.
authors.forename: S
authors.initials: S
authors.lastname: Islam
authors.forename: I
authors.initials: I
authors.lastname: Oka
authors.forename: S
authors.initials: S
authors.lastname: Fujita
mesh_terms: D005260:Female; D006228:Hand Deformities, Congenital / Q000145:classification* / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007223:Infant; D008297:Male; D011300:Preoperative Care; D011859:Radiography; D013933:Thumb / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery