Introduction: The quality of newborn hip screening is usually measured as the number of late detected cases of hip dysplasia. There is no consensus concernig the use of ultrasonography in hip joint screening in newborns. At our hospital the number of late detected cases was around 2/1000 births using clinical screening. In a prospective, randomised study we compared universal ultrasound screening and selective ultrasound screening. We reduced the number of late detected cases when using universal ultrasound screening to 0,13/1000, whereas the group with selective ultrasound screening had 0,65/1000, the difference was not significant. We have therefore continued selective ultrasound screening, and present the results concerning late detected cases in the 9-year period 1999–2007 with this screening model.

Materials and Methods: Newborns in our county are now offered selective ultrasound hip joint screening, in addition to the stanard clinical screening. The ultrasound examinations are performed 1–3 days after birth. The following risk factors lead to ultrasound examination: positive or doubtful Ortolani or Barlow tests, breech position, family history of hip dysplasia, foot deformities, and some syndromes. In the 9-year period 1999–2007 a total of 34000 babies where born in our county, and 13% had risk factors for hips dysplasia and were examined by ultrasound.

Our hospital is the only hospital dealing with lated detected cases in our county.

Results: In the 9-year period the primary treatment rate using the Frejka pillow was 0,9/1000 births. In the same period there were 16 children treated for lated detected hip dysplasia. There were 14 girls and 2 boys, giving an incidence of late detected cases of 0,47/1000 births. There were no common characteristics among the children with late detected hip dysplasia.

Discussion/Conclusions: It has been assumed that a good clinical hip joint screening in newborns should not give more than 0,5/1000 births of late detected cases. By using selective ultrasound screening we have achieved 0,47/1000 births of late detcted cases in our county. We therefore recommend selective ultrasound hip screening in newborns.