MRI
Coronal PD fat sat
Sagittal PDW_TSE_SPAIR
Sagittal PDW_TSE
Sagittal T1
Axial STIR
Axial 3D_mFFE_WATTS
MRI shows the presence of multiple geographic regions of abnormal bone marrow signal with double line sign and rim sign, more evident in both femoral condyles, medial tibial epiphysis and proximal tibial diaphysis.
The articular surface and subchondral bone plate are subtle on the lateral aspect.
Presence of bone marrow edema surrounding the area of avascular necrosing suggests a possible impending joint collapse. Oedema in the necrotic segment is seen.
These findings are in keeping with features characteristic of osteonecrosis.