Limited magnetic resonance imaging examination after surgical reduction of developmental dysplasia of the hip

Abstract

We evaluated the utility of limited magnetic resonance imaging (MRI) after surgical reduction and spica casting for developmental dysplasia of the hip (DDH) with respect to feasibility, time, need for sedation, and charge. Eighteen limited MRI examinations were performed in 10 children (mean age, 9 months) with a 1.5-T magnet. Twenty-eight dysplastic hips were imaged within 4 hours of surgery. Mean imaging time for two sequences was approximately 3 minutes. All examinations were interpretable, although three were degraded by motion. No child required sedation, additional sequences, or repeat study. Two thirds of the dysplastic hips had no proximal femoral ossification center on MRI. A reduced charge was assigned to the examination. We conclude that using limited MRI to confirm intraoperative reduction for DDH is feasible and desirable. The lack of radiation or need for sedation, the reduced charge that reflects the short time needed for imaging, and the superb visualization of nonosseous structures have made it our preferred method to evaluate surgical reduction of DDH.