Thumb lengthening by metacarpal distraction.

A case with 1-cm distraction elongation of a child's thumb metacarpal 7 years after initial injury is presented. The thumb to long finger pinch was improved by this procedure. The metacarpal elongation has been maintained for 3 years. The mechanism of this repair appears to be ossification of connective tissue. Immobilization until bony union is complete is recommended to avoid loss of length gained.