Ilizarov distraction osteogenesis over the preexisting nail for treatment of nonunited femurs with significant shortening.

PURPOSE: Nonunion of the femur with significant shortening with retained intramedullary nail (IMN) is a challenging orthopedic problem. We investigated whether the application of Ilizarov distraction osteogenesis over the preexisting nail can simultaneously achieve union and correct shortening.

METHODS: Thirteen patients with femoral diaphyseal nonunion associated with significant shortening with retained IMN were retrospectively reviewed. All patients were treated by distraction osteogenesis using a circular external fixator over the preexisting nail. The fixator was used to compress or distract the nonunion site and to gradually distract a separate osteotomy to restore limb length. The osteotomy was done percutaneously using the Gigli saw with the nail in situ. The applied surgical technique was bifocal compression distraction in 11 cases, bifocal distraction in one case, and monofocal distraction in one case.

RESULTS: Bone healing was achieved in 11 cases (84.6 %) at both the nonunion and the lengthening sites. The mean length gained was 4 cm (range, 3-6 cm). The mean time to fracture union was 4.9 months (range, 4-6 months). The mean knee flexion improved from 86.5° (range, 40°-135°) preoperatively to 109.6° (range, 60°-125°) at final follow-up (p < 0.05). The mean limb-length discrepancy improved from 4.7 cm (range, 3-7.5) preoperatively to 0.7 cm (range, 0-3) at final follow-up (p < 0.001). Ten out of 13 patients had a total of 14 complications, with a mean of 1.1 complications per patient.

CONCLUSIONS: Distraction osteogenesis over the preexisting nail can be a good alternative to treat difficult femoral diaphyseal nonunions associated with significant shortening.