To assess the comparative growth of the four long bones of the lower extremities after the tibial shaft fractures in children.

Thirty-eight children (age, 8.2±2.6) with tibial shaft fractures treated with a closed reduction and a long leg cast were enrolled in this study. The mean follow-up was 54.4 months (range, 24-96). The medical records and Bell-Thompson images were retrospectively reviewed.

The clinical results were excellent in all cases. The fractured tibia showed overgrowth (4.4±3.3 mm) compared with the contralateral side. The ipsilateral femur showed mild over-growth (0.9 mm±3.7), and the final leg length discrepancy was 5.3 mm±5.4. Four ipsilateral femurs showed overgrowth >10 mm. Gender, the level of the fractures and associated fibular fractures did not affect the overgrowth of the fractured tibia (p>0.05). However, age might affect the amount of overgrowth (p=0.005).

Tibial shaft fractures in children treated with a long leg cast showed variable overgrowth. The final leg length discrepancy was influenced by the overgrowth of the ipsilateral femur as well as by overgrowth of the tibia.