Do we need to follow up an early normal ultrasound with a later plain radiograph in children with a family history of developmental dysplasia of the hip?

Abstract

BACKGROUND: We routinely perform a pelvic radiograph between 6 and 12 months of age for children with a family history of developmental dysplasia of hip (DDH). We conducted this study to determine whether children with a family history of DDH and a normal hip ultrasound after birth require any further radiological follow-up. METHODS: We identified all children referred to our hip-screening clinic in a 3-year period between August 2008 and August 2011 with a family history of DDH and a normal hip ultrasound after birth. A total of 119 patients with a normal hip ultrasound after birth had a pelvic radiograph at a median age of 6.6 months. RESULTS: Six patients had residual dysplasia (acetabular index >30°) on the initial radiograph; five of these had resolved spontaneously by age 12 months, and the remaining patient had a normal radiograph at 21 months of age and was discharged. CONCLUSION: We have found no cases of residual hip dysplasia requiring treatment in children with a family history of DDH and a normal hip ultrasound after birth. We have therefore changed our practice accordingly and no longer routinely followed up such cases. LEVEL OF EVIDENCE: Diagnostic study, Level II.