Arthrography of the hip in children. Technique, normal anatomy and findings in unstable hip joints.

A method by which bilateral hip arthrography was performed under general anaesthesia in 130 infants and children 1 month to 7 years of age is described. Significant contractures of the adductor muscles had been corrected before the examination. Most of the children were girls with unilateral congenital idiopathic hip instability detected before the age of one year. From films exposed in standardized projections valuable information was obtained about the configuration of the joint cavity and the size and shape of the femoral head. Criteria for normal appearance in infants of ages 2 to 12 months are presented. More reliable details on the relation between the articular surfaces, the radiographic anatomy of the acetabulum and the distribution of the contrast medium were yielded by stereoradiography. Closed reduction was usually accomplished successfully during the arthrography, which made beginning of definitive treatment under the same anaesthesia possible.