Radiographic screening at four months of infants at risk for congenital hip dislocation.

We report on a radiographic screening programme at four months of age for infants who were clinically normal at neonatal examination but were considered to be 'at risk' for congenital dislocation of the hip because of their family history, breech presentation, or a persistent click. From a total population of 13,662 live births over a two-year period, 357 (2.6%) infants at risk were identified. Of these 46 had abnormal radiographs (six subluxations, 40 acetabular dysplasia). In 12 infants treatment resulted in a normal hip; 34 required no treatment but were followed up until their radiographs were normal and walking had begun. Of the 311 infants with normal radiographs, 256 (82%) were examined after 15 months of age; none had any detectable abnormality. We suggest that radiography of the hip at four months is a valuable adjunct to neonatal screening for infants at increased risk of congenital dislocation of the hip.