Hypoplastic Thumb

Abstract

with the results of operative treatment. Thumb hypoplasia. is a complex and heterogeneous congenital disorder that is

Most of the literature discussed the different modalities of treatment of different types of thumb hypoplasia or reported cases with associated anomalies. The purpose of this thesis was to characterize a group of patients with hypoplastic thumbs and to evaluate the results of operative treatment of such cases. We used the modified Blauth classification which classified thumb hypoplasia into five types (/Jiauth /967, and /Juck:Grwncko 1971) with sub-classification of Type Ill thumb hypoplasia into Types lilA and Type IJIB (Manske am/ McCarro/11-992). We added the hypoplastic triphalangeal thumb (tive fingered hand) to the classification according to'T<{iima (1985). The distribution of different types of thumb hypoplasia showed that Type V thumb hypoplasia was the most common one followed by Type IV. This agrees with the results of .lames et at (1996) This study confirms the previously reported association of variable anomalies with thumb hypoplasia (Rybka and Paletta 19711, Lister /98S, Buck (iramcko /9 77, Fhrtt /994, Manske /996 and .James 1996).The present study confirms the high incidence of radial dysplasia in association with thumb hypoplasia. Regarding the treatment, Type I tliumb hypoplasia needs no treatment. Type II is treated with opponensplasty, reconstruction of the ulnar co!late'ralligament and widening oft he first web space. The surgical treatment for Type IV, V and triphalangeal hypoplastic thumb is also straightforward (pollicization). Tvpe lilA thumbs are usually amenable to surgicai reconstruction: Type I liB thumbs, which Jack a stable base are not. The results of the surgical treatment were diflicult to be compared with other published results bC;cause there is no standardized scoring system and the difficulty of getting cooperation of very young children. However, most of the patients and parents were satisfied