A comparison of two osteotomy techniques for tibial lengthening

Introduction. There are various methods of long bone lengthening. The quality of the regenerated bone depends on stable external fixation, low energy corticotomy, latency period, optimum lengthening rate and rhythm, and functional use of the limb. Percutaneous corticotomy and ostetomy with multiple drill holes yield the best results for the quality of the regenerated bone. An alternative low energy osteotomy, which respects the periosteum, is the Afghan percutaneous osteotomy. The purpose of the current study was to compare a percutaneous multiple drill hole osteotomy with a Gigli saw osteotomy in terms of the healing index (HI). Materials and methods. Forty-four tibias of 41 patients were lengthened at our institution between 1995 and 2000. All patients underwent limb lengthening without any deformity correction by the Ilizarov device. The etiology of the limb length discrepancy was sequelae to poliomyelitis in 16 tibias, idiopathic hypoplasia in 17 tibias, posttraumatic discrepancy in 5 tibias, bilateral tibial lengthening in achondroplastic dwarfism in 3 patients. Patients with metabolic bone diseases were not included in this series. Results. The mean amount of length discrepancy was 5.7 cm (range 2-12 cm). The mean HI of the whole group was 1.65 month/cm (range 1.1-2.4 month/cm). When comparing the osteotomy methods without taking the etiology into consideration, the percutaneous, multiple drill hole group yielded a mean HI of 1.98 month/cm (range 1.4-2.4 month/cm), while the Gigli saw group yielded a mean HI of 1.37 month/cm (range 1.1-1.8 month/cm). There was a statistically significant difference between the two groups (p=0.022). The Gigli saw patients with poliomyelitis had a significantly better HI compared with patients who underwent lengthening by the other form of osteotomy (1.1 vs 1.9 month/cm; p=0.027). Conclusion. Our results confirm the biologic superiority of the Gigli saw technique.