Outcomes Following Lower Limb Corticotomy Using Multiple Drill-Hole and Gigli Saw Techniques During Distraction Osteogenesis: A Prospective Observational Comparative Study

Corticotomy is a critical step in distraction osteogenesis, with the potential to influence regenerate formation and subsequent bone healing. Multiple drill-hole and Gigli saw corticotomy are two commonly employed low-energy techniques designed to preserve the biological environment necessary for successful osteogenesis. However, evidence comparing their clinical and radiological outcomes remains limited and conflicting. This study compares the radiological, clinical, and functional outcomes of lower limb corticotomy performed using the Multiple Drill-Hole technique and the Gigli Saw technique during distraction osteogenesis.

A prospective observational comparative study was conducted in 20 patients who underwent lower limb distraction osteogenesis between October 2019 and April 2022 in a tertiary care center. Patients were prospectively categorized according to the corticotomy technique utilized during surgery. Radiological regenerate quality was assessed at six completed weeks of distraction and categorized as hypotrophic, normotrophic, or hypertrophic regenerate. Secondary outcome was assessed by the Numeric Pain Rating Scale (NPRS), operative duration, and complications. (IEC approval no.IEC/2019/72 on October 21, 2019 of Armed forces medical college).

Normotrophic regenerate was the predominant regenerate pattern in both groups. In the multiple Drill-Hole groups, regenerate morphology was normotrophic in 70%, hypotrophic in 20%, and hypertrophic in 10% of patients, compared with 80%, 10%, and 10%, respectively, in the Gigli Saw group. There was no statistically significant difference between the two groups (Fisher's Exact test, P = 1.000). NPRS score was comparable between groups, with Mann-Whitney U test values of 45.0, 47.5, and 44.0, and P = 0.63, 0.51, and 0.48, respectively. However, mean corticotomy time was significantly shorter in the multiple Drill-Hole group (10.7 min) than in the Gigli Saw group (19.9 min), with Mann-Whitney U = 0, P < 0.0001. Complication rates were comparable between groups.

Both multiple Drill-Hole and Gigli Saw corticotomy techniques produced satisfactory regenerate formation and comparable clinical outcomes during distraction osteogenesis. The findings suggest that preservation of the biological environment and adherence to established principles of distraction osteogenesis are more important than a specific corticotomy technique for successful bone regeneration.