42-year-old male with palpable loose body in the left knee MENISCI: The menisci are intact.ARTICULAR CARTILAGE AND BONE: Focal marrow signal abnormality at the posterior aspect of the lateral femoral condyle with focal area of loss of articular cartilage measuring approximately 2.4 cm in AP dimension. Moderate joint space narrowing. LIGAMENTS: The anterior cruciate ligament is intact. The posterior cruciate ligament is intact. The medial collateral ligament is intact. The lateral collateral ligament complex is intact. EXTENSOR MECHANISM: Extensor mechanism is intact.ADDITIONAL
1.Lesion in the suprapatellar fat pad. This may represent unusual synovitis such as PVNS. Cartilage also be considered although the lesion is unusual signal pattern for cartilage. Examination with intravenous contrast would be helpful.2.Focal loss of articular cartilage of the posterior aspect of the lateral femoral condyle with underlying marrow edema.