Risk factors for developmental dysplasia of the hip: ultrasonographic findings in the neonatal period.

The relationship between ultrasonographic findings at birth and risk factors for developmental dysplasia of the hip have not been prospectively evaluated. Since implementing a routine screening programme for all new-born babies in 1989 we have collected 48 000 sets of data, including family history, birth presentation, mode of delivery and birth weight. Of the 92 babies (three per 1000 live births) with persistent ultrasonographic abnormality at 6 weeks only 20% displayed evidence of clinical instability at the original examination. Female babies without the additional risks of breech birth or positive family history were quantitatively the most significant group, accounting for 75% of cases treated. The majority of babies requiring intervention would not have been identified utilizing present criteria for selective ultrasound screening.