Ultrasound screening for developmental dysplasia of the hip in the newborn: a population-based study in the Maribor region, 1997–2005

Abstract

Ultrasound imaging has become an accepted tool for accurate diagnosis of developmental dysplasia of the hip (DDH) and for its management. The aim of the present study was to evaluate the results of the general neonatal hip screening program in Maribor between 1997 and 2005 in comparison with earlier reported results for our region, where this program was introduced in 1985. Of the total number of 17,846 newborns born in our maternity hospital, 17,393 were included in the study during the nine-year period. All hips were examined by ultrasonography within the first week of life. Data for 2.5% of newborns were not available. The incidence of sonographic hip types according to the Graf method was analyzed, together with the sex distribution, lateralization of hip pathology and treatment recommendations. A total of 34,786 hips were evaluated sonographically: 84.9% of hips were mature at first examination (Graf types Ia and Ib), 14.1% were immature (Graf type IIa) and 1.1% were pathological (Graf types IIc or worse). In the group of pathological hips, girls were more frequently affected than boys (3.9:1) and the left hip was more frequently affected than the right (1.2:1). The incidence of hip types IIc or worse decreased sevenfold throughout the observation period, from 2.1 in 1997 to 0.3 in 2005. This distribution of hip types resulted in an average treatment rate of 18 newborns per 1000 live borns, down from 42 treated hips per 1000 newborns in 1997 to 6 hips per 1000 in 2005. During this nine-year period, only 19 children required surgical treatment for DDH before the age of three years. In our region, general ultrasound hip screening of newborns for DDH seems to be effective in reducing the overall treatment rate. The number of surgical procedures has remained stable during the past nine-year screening period and is lower than in the pre-ultrasound era.