Nonunion following subcapital (neck) fractures of the proximal phalanx of the thumb in children.

Six cases of nonunion of subcapital (neck) fractures of the proximal phalanx of the thumb in children were seen over a period of 5 years. Ages at the time of injury ranged between 2 and 3 years. Entrapment of the thumb in a closing door was the mechanism of injury in all cases. All fractures were closed and were significantly displaced. Immediate management was by closed reduction and splinting in four cases, closed reduction and K-wire fixation in one case and no treatment in one case, which was later treated by delayed open reduction and K-wire fixation. Only two of the six ununited fractures were eventually treated with bone grafts and both fractures united resulting in a stable thumb but with a limited range of flexion of the interphalangeal joint. Factors that may increase the risk of nonunion of these fractures in children are discussed.