Enhanced detection services for developmental dysplasia of the hip in Scottish children, 1997-2013

Background Developmental dysplasia of the hip (DDH) remains common. If detected early, DDH can usually be corrected with conservative management. Late presentations often require surgery and have worse outcomes. Objective We estimated the risk of undergoing surgery for DDH by age 3 years before and after the introduction of enhanced DDH detection services. Design Retrospective cohort study. Setting Scotland, 1997/98-2010/11. Patients All children. Methods Using routinely collected national hospital discharge records, we examined rates of first surgery for DDH by age 3 by March 2014. Using a difference in difference analysis, we compared rates in two areas of Scotland before (to April 2002) and after (from April 2005) implementation of enhanced DDH detection services to those seen in the rest of Scotland. Results For children born in the study period, the risk of first surgery for DDH by age 3 was 1.18 (95% CI 1.11 to 1.26) per 1000 live births (918/777 375). Prior to April 2002, the risk of surgery was 1.13 (95% CI 0.88 to 1.42) and 1.31 (95% CI 1.16 to 1.46) per 1000 live births in the intervention and non-intervention areas, respectively. In the intervention areas, from April 2005, this risk halved (RR 0.47; 95% CI 0.32 to 0.68). The risk remained unchanged in other areas (RR 1.01; 95% CI 0.86 to 1.18). The ratio for the difference in change of risk was 0.46 (95% CI 0.31 to 0.70). Conclusions The implementation of enhanced DDH detection services can produce substantial reductions in the number of children having surgical correction for DDH.