Ultrasound of the neonatal hip as a screening tool for DDH: how to screen and differences in screening programs between European countries

Developmental dysplasia of the hip comprises a broad spectrum of abnormalities in hip development, of variable severity. Besides physical examination, ultrasound is the preferred imaging modality for screening for developmental dysplasia of the hip in children aged younger than six months. The Graf method is the most widely used ultrasound technique for infant hips; a stepwise approach will be shown in this article. Furthermore, the process of dynamic ultrasound imaging will be explained as well as the use of transinguinal ultrasound in infants wearing a spica cast. There is no consensus on the best way to screen for developmental dysplasia of the hip, which is probably the reason why different screening programs exist throughout Europe, as will be discussed in this article. The use of universal versus selective ultrasound remains a controversy, as does the timing. Is it better to perform sonography in all newborn infants like in Germany and Austria? Or should we examine only the infants with clinical hip instability or risk factors (breech position, positive family history), like in the UK and the Netherlands? This article reviews the epidemiology, static and dynamic ultrasound techniques in screening for developmental dysplasia of the hip, and differences in screening programs throughout Europe. Set aside the uncertainties about whom and when to screen, it needs to be emphasized that ultrasound screening for developmental dysplasia of the hip is important, since the disease is initially occult and easier to treat when identified early. In this way, the radiologist can aid in preventing serious disability of the hip.