71-year-old male with a small mass in the right posterior lateral knee. Presents with right lower leg pain. MENISCI: There is increased signal abnormality which extends to the femoral and tibial articular surfaces and is associated with deformity of the posterior horn of the medial meniscus consistent with radial and degenerative tearing. The lateral meniscus appears intact.ARTICULAR CARTILAGE AND BONE: There is thinning of the articular cartilage most pronounced along the medial tibiofemoral compartment without evidence of full-thickness or near full-thickness articular cartilage defect. No bone marrow signal abnormality is identified.LIGAMENTS: The cruciate and collateral ligaments appear intact. EXTENSOR MECHANISM: The extensor mechanism appears intact.ADDITIONAL
1. Slight interval increase in size of the reference mass along the posterolateral aspect of the left knee which may represent a peripheral nerve sheath tumor such as a schwannoma.2. Tearing of the posterior horn of the medial meniscus, as described above.