18-year-old male patient with history of sickle cell anemia and abnormal right knee radiograph. MENISCI AND LIGAMENTS: The medial and lateral menisci are intact. The anterior cruciate alignment, posterior cruciate ligament, lateral collateral ligament, and medial collateral ligament complex are intact.BONE AND MARROW: Increased T2 signal in the medullary cavity of the distal femoral metaphysis and proximal tibial metadiaphysis with thick peripheral enhancement. The abnormal T2 signal in the distal tibia extends to the cortex posteriorly.SYNOVIUM: No joint effusion or synovitis.MUSCULATURE: The musculature is normal in appearance.ADDITIONAL
Findings compatible with bone infarct in the distal femur and proximal tibia. Extra-osseous focus of increased T2 signal along the posterior femoral bone infarct may be reactive due to new bone formation or weakening of the cortex/periosteum.