Screening for developmental dysplasia of the hip: from theory to practice. Collaborative Group DDH Project.

OBJECTIVE: To evaluate an organizational model for neonatal population screening for developmental dysplasia of the hip.

METHODS: In 4648 neonates born in six hospitals of the Lombardy region, screening for developmental dysplasia of the hip was done using the Ortolani-Barlow maneuver and ultrasonography.

RESULTS: The frequency of positive results of clinical and ultrasound examinations carried out in the hospitals varied considerably as a result of difficulties in the Ortolani-Barlow test reproducibility and in the low sensitivity of the clinical examination when compared to ultrasonography. Neonatal screening results implied a large number of subjects with a IIa hip, according to Graf's system; as these subjects require follow-up, the cost of this type of screening is high. Ultrasound findings were normal at 69 days of life in 88% and 75% of subjects, respectively, with unilateral and bilateral type IIa hip.

CONCLUSION: This study evaluated various organizational models for screening (for different time periods and for selected populations) in relation to the cost-benefit ratio and demonstrated the different problems that still impede identification of a correct screening model.