Femoral head volume indicates the severity of developmental dysplasia of the hip by a method using three-dimensional magnetic resonance imaging.

The aims of this study were to quantify the femoral head volume (FHV) in developmental dysplasia of the hip (DDH) and to estimate its relation with the severity of the disease. Fifty-one patients (age range 2-11 months) with unilateral DDH were evaluated using three-dimensional MRI. The relation among FHV, age, severity, and displacement was investigated. The affected FHV gradually decreased according to severity. Cephalad displacement of the femoral head correlated negatively with FHV. This new approach showed severity-dependent growth disturbance of the femoral head. This quantification is a promising technique for understanding the pathology of DDH.