Concordance between hip ultrasonography and hip arthrography in the assessment of developmental dysplasia of the hip.

Abstract

Controversy exists regarding the possibility of predicting hip reducibility in the congenitally dislocated hip, with arthrography still regarded as the gold standard in this situation. This study aims at assessing the degree of concordance between ultrasonography and arthrography in the detection of anatomic elements obstructing hip reduction. Forty-nine hips were studied both by ultrasonography and arthrography. Three anatomic sources of obstruction to reduction were assessed in each hip: ligamentum teres hypertrophy, inverted labrum, and the presence of soft tissue in the acetabulum. For each variable, congruence between ultrasound and arthrography was measured by kappa analysis. Values > 0.40 expressed sufficient concordance, and they were detected with regard to inverted labrum and the presence of soft tissue in the acetabulum. The results of this study suggest that ultrasonography may be considered a reliable technique for the prediction of the main causes of obstruction in the congenitally dislocated hip, such as inverted labrum and soft tissue in the acetabulum.