Legg-Calvé-Perthes disease: multipositional power Doppler sonography of the proximal femoral vascularity.

BACKGROUND: Selection of the most appropriate sonographic scanning approaches for evaluation of hips can improve the method efficacy and decrease the scanning time.

OBJECTIVE: To determine the sonographic scanning planes that best assess the proximal femoral vascularity in asymptomatic and pathologic hips of children with Legg-Calvé-Perthes disease (LCPD) and evaluate the frequency (number of hips with evidence of perfusion) and intensity (number of color pixels per region) of color pixels representing superficial cartilaginous and deep transphyseal vascularity in different anatomic regions of pathologic and asymptomatic hips using multipositional power Doppler approaches.

MATERIALS AND METHODS: Seven scanning approaches (anterior-sagittal, anterior-transverse, coronal, adduction, perineal, 30 degrees and 70 degrees of abduction) were applied in 26 pathologic hips of 26 children with LCPD (age range 3-11 years) and in 25 contralateral asymptomatic hips. The color Doppler signals seen within the proximal femur were analyzed both qualitatively (overall/regional frequency) and quantitatively (intensity).

RESULTS: The coronal (P=0.009) and 30 degrees abduction (P=0.047) approaches demonstrated a higher frequency of color pixels in pathologic than in asymptomatic hips. The anterior-sagittal, 30 degrees abduction, adduction and anterior-transverse planes performed best of all approaches (P=0.02) to assess deep transphyseal perfusion. The physis demonstrated a greater intensity of color signals representing intraosseous vascularity than other regions in pathologic hips (P=0.027), as noted with the anterior-sagittal approach. There was a tendency (P=0.06) towards a greater intensity of pixels representing cartilaginous vascularity in pathologic hips' physes with the coronal approach.

CONCLUSION: Specific sonographic scanning planes are recommended for assessment of the proximal femoral vascularity of LCPD hips. The physis is the anatomic region that presents with the greatest intensity of color signals in pathologic hips.