Ultrasound of the infant hip. Part 1. Basic principles.

Method and the basic principle of infant hip studies by means of ultrasound are described. It is the purpose of this imaging modality to detect dislocations and dysplasia at an early stage. The visible structures of the hip-joint are shown in histologic-sonographic correlation. Based on the pathomechanics of hip-dysplasia diagnostic criteria for ultrasound studies are developed. Our classification system, in close similarity to Graf, is presented.