[A sonographic study of the hips in neonates and infants].

A comparative study between X-ray and ultrasonography was carried out in the hips of neonates and infants, for the purpose of evaluating the usefulness and possibility of the latter method. We studied 902 hips between the ages of one day and eighteen months. Thirty-seven dislocations, seventeen subluxations, and eighty eight dysplastic hips were detected by X-ray. A sonographic study was done by Graf's method. All dislocations and subluxations could be diagnosed by ultrasonography too, but about half of the dysplastic hips could not be distinguished from normal hips by this method. This method is more useful than X-ray for patients under the age of three months, since the cartilaginous femoral head and the soft tissues around the hip could be clearly visualized. Ultrasonography thus appears to be a useful screening method for congenital dislocation of the hips without the hazard of radiation caused by X-ray.