ABSTRACT
BACKGROUND: The methods used for any screening programme for developmental dysplasia of the hip (DDH) can be controversial. This was an opportunistic audit of our selective ultrasound screening programme using an X-ray at 5 months to prevent inappropriate discharge due to the learning curve of ultrasound. METHODS: Between 1990 and 2004 in Nottingham, UK, out of a total population of 108,500 births, approximately 11,500 neonates were screened using ultrasound. Any child with an ultrasound scan showing Graf α-angles greater than 60° (Graf Type I) with the hip in joint were discharged from the clinic. All of those discharged were subsequently X-rayed at 5 months in order to cover the learning curve of ultrasound. The X-rays were reviewed by a consultant radiologist and referred back to orthopaedics if there was lateralisation of the femoral head or an acetabular index above 30°. RESULTS: Of approximately 11,000 X-rays performed, only 53 patients were referred back to orthopaedics, of which 47 had a complete data set. Of these 47 children, only 8 (17%) required intervention. On review of the original ultrasounds, Graf's α-angle did not seem to correlate well with the need for intervention, as all were Type I hips. The femoral head cover (FHC) appeared to be more predictive of the need for treatment. There have been no late presentations to our unit of DDH following a normal 5-month X-ray. CONCLUSIONS: We now check the Graf α-angle, FHC and dynamic stability in the ultrasound assessment and only perform X-ray at 5 months if there was a low α-angle or low FHC. Since this change, there have been no late presentations of DDH from the population screened by ultrasound.
