Hr. Song et al., Classification of metaphyseal change with magnetic resonance imaging in Legg-Calve-Perthes disease, J PED ORTH, 20(5), 2000, pp. 557-561
Seventy-eight patients (85 affected hips and 71 unaffected hips) with Legg-
Calve-Perthes disease were included in this study to evaluate the metaphyse
al change in radiographs and magnetic resonance imaging (MRI) and to define
the type of the metaphyseal cyst according to presence or absence of the e
piphyseal involvement. The content of the metaphyseal cyst was evaluated by
using T1, T2, proton, and gadolinium-enhanced T1-weighted MRI scans. Among
85 hips, there were no changes in 32 hips, marrow edema in 13 hips, false
cyst with epiphyseal involvement in 28 hips, and true cyst without epiphyse
al involvement in 12 hips. Granulation tissue was found in the false cysts
and water-rich fibrotic tissue was found in the true cysts based on the MRI
, scans. The metaphyseal change in MRI scans was shown in 71% of groups 3 a
nd 4 and in 35% of groups 1 and 2 according to the Catterall classification
, and 52% of group A, 56% of group B, and 86% of group C according to the H
erring classification. Of the 30 hips at the avascular stage, 33% showed me
taphyseal cyst in MRI scans. Of the 53 hips at the fragmentation stage, 60%
showed the metaphyseal cyst.