Digital lengthening in congenital hand deformities.

12 hands with congenital short finger in 11 patients were treated with various types of metacarpal bone lengthening. These included three patients with brachydactyly, seven with transverse deficiency, and one with constriction ring syndrome. All cases involved metacarpal lengthening and surgery was performed 16 times in 15 digits. Single-stage lengthening was performed in seven cases, on-top plasty in three cases, and distraction lengthening in six cases. The length gained ranged from 2 to 10 mm in single-stage lengthening, 3 to 17 mm in on-top plasty, and 12 to 30 mm in distraction lengthening. Delayed union and malunion occurred in single-stage lengthening or on-top plasty. After metacarpal lengthening, pinch function was improved in seven out of eight patients with either transverse deficiency or constriction band syndrome, and aesthetic improvement was achieved in three patients with brachydactyly.