The ultrasonic image of the acetabular rim in infants. An experimental and clinical investigation.

We report about the possibilities to evaluate the fine structures of the area around the acetabular rim in infants using ultrasound. The identification of the rim within the joint capsule, limbus and cartilagineous preformed acetabular rim is explained by experimental investigations. The clinical use of ultrasound provides a diagnostic method which is painless, non invasive and especially avoids X-ray exposure. It also can be repeated as often as possible. First statements could be made about the above mentioned structures, not visible on the radiograph, according to routine ultrasonic examinations of infantile hip joints, performed to exclude a luxation. We also point out the prognostic value of the cartilagineous acetabular rim demonstrated by ultrasound.