Abstract
Purpose
There is concern that the positive predictive value (PPV) of neonatal screening for instability may have deteriorated over recent years, this study aims to evaluate this.
Method
This is a prospective observational longitudinal study from 2012 – 2016. Patients that were referred from paediatric neonatal screening with hip instability (Ortolani / Barlow positive, clunks) were identified and underwent ultrasound and clinical examination in the one stop hip clinic by the senior author. Referrals were taken from a range of screeners from paediatric doctors to midwives and advanced neonatal practitioners. Syndromic or neurological dislocated hips were excluded. The outcome measures were the presence of a subluxated / dislocated hip on ultrasound as per Graf and Harcke classification and a positive provocative manoeuvre on examination. This allowed a PPV to be evaluated for both ultrasound and clinical examination.
Results
139 neonates were referred for a suspected dislocated or dislocatable hip from paediatric screening services. These were seen at a mean 14.0 days (95% C I, 12.28 to 15.72). 20 patients had a Graf type 4 hip on ultrasound and 5 had a positive provocative test on examination. This represents an ultrasound PPV of 14.4% and clinical exam PPV of 3.6% . This has deteriorated from 15 year data from our unit (PPV 24% clinical, 49% sonographic). Our overall surgical rate for DDH has increased to 1.07 per 1000, and our overall rate of open reductions has increased to 0.7 per 1000. This is based upon figures from 2012 – 2014.
Conclusion
The PPV of screening has decreased over the last 5 years. The concern is too many screeners who, with regards screening the paediatric hip, are poorly trained, inexperienced, not adequately supervised. We need to learn the lessons of Sweden and ensure better quality screening by limiting screening to a small number of experienced practitioners.