Presentation
Right knee pain in a patient under long-term steroid therapy for an autoimmune disease.
Patient Data
Intramedullary serpiginous lesions involving the lateral aspect of the distal femoral metaphysis, lateral femoral condyle and proximal metaphysodiaphyseal region of the tibia. They elicit iso-to hyposignal to the normal bone marrow on T1 centrally and a low signal peripheral rim (granulation tissue). The T2 and PD fat sat sequences show a double-line sign.
Normal appearance of both menisci, cruciate and collateral ligaments.
Case Discussion
MRI features most consistent with bone infarction in a patient under long-term corticosteroid therapy for an autoimmune disease.