hand deformities
Last reviewed 01/2018
The hand deformities in ulnar dysplasia are predominantly those of missing digits. Typically these are on the ulnar side of the hand and the most common scenario is for both of these digits to be absent. However, all digits including the thumb can be deficient. The digits that remain can be abnormal. Some are hypoplastic, have a missing phalanx or metacarpal, whereas others may show accessory bones including longitudinal bracketed epiphyses. Synostoses may be seen, particularly between the terminal phalanges.
Despite the ulnar side of the limb exhibiting the greatest abnormality, the radial side may also be deficient. There may be hypoplasia or aplasia. The first web space may be narrowed. The spectrum of thumb abnormalities led to the classification scheme of Cole and Manske (see submenu).