Remodelling of Angular Deformity in Birth-Associated Femoral Shaft Fracture

ABSTRACT

PURPOSE: To find out the process of bone remodelling and risk factors in birth-associated femoral fracture. MATERIALS AND METHOD: We evaluated the four femoral fractures in three neonates about the obstetric and family history, and measured the angulation at the fracture site and the angle between the proximal and distal epiphysis of the femur on the radiographies taken at regular intervals. RESULTS: The incidence of birth-associated femoral fracture was 0.06%. In two cases, fracture angulation and interepiphyseal angle had been decreased. However the angular deformity was worsened in two cases, but the interepiphyseal angle had been decreased regardless to the change of fracture angulation. So the alignment of epiphyseal plate came to normal alignment of joint surface. CONCLUSION: The underlying disorder should be searched, because of its rarity. The physeal reorientation that makes joint alignment near normal irrespective of amount of angular deformity is assumed as the predominant mechanism in remodelling process of the angular deformity.