Characteristic features of the acetabular labrum in healthy children

Radial magnetic resonance images of the acetabular labrum were obtained on 40 hips of healthy children. There were no right-left or male-female differences. In children aged 11 years or younger, the labrum on the antero-superior weightbearing portion was triangular in shape, and there was an insular-shaped or linear high-intensity area inside; on the mid-superior portion, the labrum appeared as a regular triangular, low-intensity area; and on the postero-superior portion, it was flat. In children aged 12 and 13 years, the shape of the labrum in each portion was similar to that of the younger children, but the high signal intensity area on the antero-superior portion appeared less frequently. The size of the labrum relative to the femoral head was greater in younger children.