66-year-old female with a history of rheumatoid arthritis and effusion. MENISCI: The medial meniscus appears intact. The lateral meniscus appears intact.ARTICULAR CARTILAGE AND BONE: There is full-thickness articular cartilage degeneration along the lateral facet of the patella with large areas completely devoid of articular cartilage. There is underlying degenerative subchondral signal abnormality and subchondral cyst formation. There is near full-thickness to full-thickness articular cartilage degeneration along the median eminence of the patella and medial facet with underlying subchondral signal abnormality. There is full-thickness articular cartilage degeneration along the lateral facet of the femoral trochlea with large areas completely devoid of articular cartilage. There is focal full-thickness articular cartilage degeneration along the weightbearing portion of the lateral tibial plateau and lateral femoral condyle, as seen on the coronal images.LIGAMENTS: The cruciate and collateral ligaments appear intact. EXTENSOR MECHANISM: The extensor mechanism appears intact. There is a small amount of fluid within the deep infrapatellar bursa.ADDITIONAL
1. Borderline tibial tubercle to trochlear groove distance, patella alta, edema within the superolateral aspect of Hoffa's fat pad, and patellofemoral joint articular cartilage degeneration may be seen in patient's with patellofemoral instability.2. Small joint effusion.