Distraction lengthening of the ulna in children with radial longitudinal deficiency.

PURPOSE: Children with radial longitudinal deficiency have very short forearms. The Ilizarov method of distraction osteogenesis has been used to increase extremity length, but results differ with the underlying condition and the limb being lengthened. The purpose of this study is to examine retrospectively the outcomes of Ilizarov lengthening of the ulna in children with radial longitudinal deficiency.

METHODS: Nine children with radial longitudinal deficiency had 13 ulnar lengthenings using the Ilizarov method; 8 with unilateral deficiency had 9 lengthenings to improve appearance, and 1 child with bilateral radial longitudinal deficiency had 4 lengthenings to improve function. All had previous wrist centralization surgery, and all but 1 had a carpal osteotomy at the time of lengthening to reduce residual wrist angulation.

RESULTS: The average gain for each lengthening was 4.4 cm (range 1.8-8.0 cm) with an average lengthening index of 9 weeks per cm (range 4-24 weeks per cm). All patients at each lengthening experienced at least 1 pin site infection that required antibiotic treatment. Other complications included delayed union requiring internal fixation and bone grafting in 3 lengthenings and recurrence of radial deviation requiring shortening and wrist arthrodesis in 1 case.

CONCLUSIONS: The Ilizarov technique is an effective method for lengthening the ulna in children with radial longitudinal deficiency. The process of lengthening is prolonged and arduous with frequent complications. In successful cases, however, patients are pleased with the function and appearance of their lengthened forearms.