75-year-old woman with history of osteoarthritis and intra-articular pain. MENISCI: The medial and lateral menisci are intact without evidence of tear.ARTICULAR CARTILAGE AND BONE: There is thinning of the articular cartilage over the medial femoral trochlea with with an approximately 12 mm bare area, underlying reactive marrow change, and a 5 x 5 mm subchondral cyst (series 7, image 14). There is significant thinning of the articular cartilage over the medial patellar facet with underlying reactive marrow changes. Additionally, there is fissuring of the articular cartilage over the lateral patellar facet with underlying marrow change. The articular cartilage of the tibial femoral compartment is thinned without full-thickness loss.LIGAMENTS: The ACL, PCL, MCL, and LCL complex are intact. The popliteus muscle and tendon are intact. EXTENSOR MECHANISM: The patella and extensor mechanism are intact.ADDITIONAL
1. Articular cartilage loss predominantly over the medial patellofemoral compartment with underlying reactive marrow change and subchondral cysts.2. Findings compatible with prepatellar bursitis.