PEDIATRIC HIP EFFUSIONS - EVALUATION WITH POWER DOPPLER SONOGRAPHY

PURPOSE: To determine if power Doppler sonography allows differentiati on of infectious from noninfectious hip effusions and thereby obviates joint aspiration. MATERIALS AND METHODS: Twenty-nine consecutive chil dren (30 hips) with sonographically identified hip effusion were prosp ectively evaluated with power Doppler sonography. Both hips were evalu ated in each patient by using identical imaging parameters and were th en compared. Medical charts were reviewed to determine the eventual di agnosis. RESULTS: At power Doppler sonography, none of 16 patients wit h transient synovitis had increased flow in the affected hip compared with the contralateral normal hip. Of 11 patients with septic arthriti s, one had asymmetric increased flow, and two others, in whom contrala teral comparison images were limited, had probable increased flow. Thr ee patients with miscellaneous diagnoses had asymmetric normal flow. C ONCLUSION: Because power Doppler sonograms did not depict increased fl ow in most patients with septic arthritis, normal flow on power Dopple r sonograms does not allow exclusion of septic arthritis and should no t preclude aspiration when clinically warranted.