Radiopaedia.org

There is bilateral diffuse abnormal marrow signal throughout the femoral and tibial metaphyses which is characterized by T2 hyperintensity and T1 hypointensity. Of note, these areas also demonstrate abnormal enhancement on the postcontrast images. There is no evidence of cortical disruption. However, abnormal signal and enhancement does extend along the sub-periosteum. Additional areas of abnormal soft tissue edema and post contrast enhancement surrounding the metaphyses are most notable surrounding the knees and ankles. Abnormal soft tissue signal involves the vastus medialis muscles bilaterally, and to a lesser extent the vastus lateralis and the short head of the biceps femoris muscle bilaterally.