Screening program for neonates at risk for developmental dysplasia of the hip: comparing first radiographic evaluation at fivemonths with the standard twelveweek ultrasound. A prospective cross-sectional cohort study

摘要

PurposeTo assess whether delayed radiological hip screening at fivemonths (versus ultrasound at 3months) results in a higher incidence of persistent developmental dysplasia of the hip (DDH) at 18months.MethodsWe analyzed 3536 screened neonates (2009-2013) at age two to threeweeks. In the case of risk factors for DDH, 460 infants were assigned to a pelvic radiograph at fivemonths between 2009 and 2010 and 651 infants were assigned to an ultrasound at threemonths (2011-2013). In the case of DDH, appropriate treatment was started and radiological follow-up occurred at eight, ten, 12, and 18months. We compared incidence and severity of persistent DDH at 18months. Analysis was performed using linear regression.ResultsBoth groups were comparable for risk factors (breech, gender, twins, family history). Eighty-nine patients (2.5%) showed DDH (n=43 (group 1), n=46 (group 2)). At 18months, ten patients showed persistent DDH (n=8 (group 1), n=2 (group 2) (7.7% vs. 0.3% respectively)). The mean acetabular index (AI) at 18months in group 1 (left hip) is 22.4 degrees (95% CI 20.6-24.3 degrees) vs. group 2 at 22.3 degrees (95% CI 21.2-23.4 degrees) (p=0.098). The mean AI in group 1 (right hip) is 21.9 degrees (95% CI 18.9-24.9 degrees) vs. 21.2 degrees (95% CI 20.5-22.0 degrees) in group 2 (p=0.293). Adjusted for risk factors, there is no difference in incidence of persistent DDH between both groups after 18months (OR 0.519; 0.07, 3.845).DiscussionThis study revealed no significant difference in incidence or severity of persistent DDH at 18months between the two screening groups. These results suggest justification for delayed screening to prevent overtreatment of immature hips.ConclusionIn clinically stable hips, delayed ultrasound between three and fivemonths is regarded as safe and could prevent for overtreatment of mild dysplastic hips.