TREATMENT OF COMPLEX HYPERTROPHIC NONUNIONS BY CLOSED ILIZAROV DISTRACTION

Abstract

Introduction and Aims: Distraction osteogenesis can be used to stimulate healing in hypertrophic non-unions (HNU). We evaluated the use of closed (without opening the non-union) Ilizarov distraction for HNU with associated angulation, malrotation, and shortening.

Method: Sixty-seven consecutive patients (mean age, 38.3 years) with 71 HNU were treated (1988–2001) using Ilizarov distraction. Patients had undergone an average of five previous operations. HNU classified as stiff (< 5 degrees mobility) were distracted, and those classified as partially mobile (5–20 degrees mobility) were first compressed and then distracted.

Results: Non-unions included: 59 tibiae, six femora, two radii, and five ankle arthrodeses. Mean limb length discrepancy, 3.5cm; mean deformity, 16°; history of osteomyelitis, six cases. Closed distraction alone was successful in achieving union in 61 cases (86%) (mean follow-up, six years; mean time to union, eight months). Union rate was 91.6% (55 of 60 cases) for stiff HNU and only 54% (six of 11 cases) for partially mobile HNU. Distraction treatment alone failed to achieve union in 10 cases. In seven, union was achieved after bone grafting. Two required resection of infected non-union with bone transport to achieve union. One had persistent non-union. There were numerous superficial pin infections and three deep infections. Two cases had deformity at proximal tibial lengthening osteotomy site.

Conclusion: Closed distraction is safe and reliable for stimulating union in stiff HNU. It is especially effective in a scarred limb that has undergone previous operations. It allows for simultaneous correction of deformity and length. Main disadvantage is lengthy time spent in external fixator.