Management of hypertrophic nonunion with failure of internal fixation by distraction osteogenesis.

Introduction And Aim: Distraction osteogenesis is employed in the management of hypertrophic nonunion associated with angular deformity and shortening. This study was aimed at evaluating the outcomes of Ilizarov apparatus without bone graft or open osteotomy in cases of hypertrophic nonunion not responding to treatment with internal fixation.

Methods: We retrospectively reviewed the data of 12 patients (mean age, 46.5 years) treated for hypertrophic nonunion at our institution. All patients had two-plane angular deformities (mean, 19° and 23.5° in sagittal and frontal plane, respectively) and limb-length discrepancy (mean, 3.8cm). The Ilizarov apparatus was used to simultaneously treat the nonunion, malalignment, and limb-length discrepancy.

Results: The mean follow-up duration after the removal of the apparatus was 42 months. In all cases, bone union had been achieved within an average of 8 months after a single surgery, without the need for any additional procedure. Additionally, none of the patients had recurrence of limb-length discrepancy or malalignment during the follow-up period. Complications of superficial pin-tract infections and mild Achilles tendon contracture were observed, but they resolved over time. All patients were satisfied with the outcome of the surgery.

Conclusion: Patients with hypertrophic nonunion associated with internal fixation failure can be treated by using the Ilizarov apparatus, thereby eliminating the need for bone graft or open osteotomy. Distraction osteogenesis appears to be effective as a minimally invasive percutaneous procedure in the treatment of hypertrophic nonunion with deformity and shortening.