Sonography of hip dysplasia

Abstract

Early diagnosis of developmental dysplasia of the hip (DDH) is important to institute appropriate treatment and reduce the incidence of long-term complications. Risk factors for DDH include genetic, developmental, mechanical, and physiologic factors. Physical examination using Ortolani and Barlow maneuvers is standard for early detection. Plain film radiography is limited for the diagnosis of DDH even when applying several classic landmarks, lines, and measurements, due to the lack of visualization of the cartilaginous components of the infant's hip. Ultrasound arose as a tool for evaluation of the cartilaginous structures of the hip in the early 1980s. Graf's method of examination by ultrasound stresses morphology, whereas dynamic examination uses physical maneuvers to elicit laxity of the hip. The Pavlik harness is the mainstay of treatment of DDH in the young infant, and ultrasound examination in the harness is useful to monitor progress. Closed or open surgical reduction is reserved for unresponsive or advanced cases. Universal ultrasound screening of newborns is not deemed cost effective by most North American authors, although in Europe non-selective screening has been more widely used.