Radiological Analysis of Bone Regeneration in Different Tibial Distraction Osteogenesis Zones and Parts

This study aimed to explore whether asymmetrical bone regeneration is present in tibial distraction osteogenesis (DO) and analyze its etiologies.

In total, 56 patients with tibial bone defects treated with DO were retrospectively analyzed (38 men and 18 women; average age, 47.3 years). Single proximal DO was conducted for 30 patients, single distal DO was conducted for 16 patients, and both proximal and distal DO were conducted for 10 patients. Bone regeneration, notably the healing time of the proximal and distal zones and different DO parts, was analyzed via radiological examination, and the possible etiologies were investigated.

There were 5 patients with poor regenerate formation (4 in the distal and 1 in the proximal), 3 patients with premature mineralization in the proximal, and 3 patients with DO zone fracture (1 in the proximal and 2 in the distal). The proximal healing time (11.8 ± 2.3 months) was shorter than the distal healing time (13.2 ± 2.5 months) (p = 0.040). The posterior part had the shortest healing time (10.4 ± 1.8 months), followed by the lateral part (11.1 ± 2.2 months) and the medial part (11.6 ± 2.5 months). The anterior part had the longest healing time (12.5 ± 3.8 months). Furthermore, pairwise comparison showed that the posterior and the anterior parts were significantly different from the other parts (p < 0.05).

Bone regeneration in different tibial DO zones and parts is asymmetrical, with faster regeneration in the proximal zone and posterior part and slower in the distal zone and anterior part, which may be due to differences in the local biological and external environments. These findings suggest that different distraction rates can be applied in different tibial regions, and more attention should be paid to protecting the anterior tibia.