Left knee instability MENISCI: There is maceration of the lateral meniscus with only a small remnant of the anterior horn remaining. The medial meniscus appears intact.ARTICULAR CARTILAGE AND BONE: There is severe full-thickness cartilage loss of the medial compartment of both the femoral condyle and tibial plateau. There is associated degenerative marrow edema in the underlying subchondral bone. There is moderate thinning of the articular cartilage of the medial compartment with areas of near full-thickness degeneration as well. There is heterogeneity and partial-thickness loss of the medial patellar facet and associated femoral trochlea. The articular cartilage of the lateral patellar facet is preserved.LIGAMENTS: The anterior cruciate ligament is absent. PCL is intact. The MCL is intact. The lateral collateral ligament complex is performed. EXTENSOR MECHANISM: There is increased signal and thickening of the distal portion of the patellar tendon with osteophyte formation of the anterior tibia. The quadriceps tendon is intact.ADDITIONAL
1. Ruptured ACL.2. Maceration of the lateral meniscus.3. Severe osteoarthritis of the lateral compartment with moderate changes noted in the medial and patellofemoral compartment.4. Rupture of the lateral collateral ligament complex.5. Large joint effusion and Baker's cyst containing small foci of low signal intensity which likely reflect a combination of synovitis and/or debris/loose bodies. 6. Thickening and increased signal of the distal portion of the patellar tendon which may reflect partial tearing or tendinosis.