Forty children treated non-operatively for fractures of the femoral shaft were reviewed with regard to differences in limb length after treatment. Follow up duration ranged from two to seven years. The average femoral overgrowth was 0.85cm (range 0 - 2.5cm) and was influenced by age at the time of fracture. We were not able to find any association between the quantity of overgrowth and race, gender, level or configuration of the fracture.