DEVELOPMENT OF THE ACETABULUM AND HIP - COMPUTED-TOMOGRAPHY ANALYSIS OF THE AXIAL-PLANE

Acetabular growth and development in the axial plane was evaluated by computed tomography (CT) scan. One hundred seventy normal hips of chil dren ranging in age from 6 months to 17 years were evaluated for axial acetabular index, anterior and posterior center-edge angles (CEA), an d acetabular anteversion. The acetabulum deepens and becomes increasin gly spherical with time until the age of 13 years. Little further chan ge in acetabular shape occurs once the triradiate cartilage closes. Cl osure ensues between the ages of 11 and 13 years, occurring slightly e arlier in girls. Posterior bony coverage of the femoral head is greate r than anterior coverage at all times. Acetabular anteversion showed l ittle change as the acetabulum developed. Establishing normal values f or axial development of the hip and acetabulum allows a better three-d imensional concept of the different pathologic conditions and aids in treatment planning.