58-year-old female with left posterior knee pain. MENISCI: There is globular increased signal abnormality within the posterior horn of the medial meniscus consistent with intrasubstance degeneration. There is a horizontal tear of the posterior horn of the meniscus with a flipped meniscal fragment extending anteriorly along the medial aspect of the PCL, best seen on coronal series 6, images 8 through 12. The anterior horn appears intact. The lateral meniscus appears intact.ARTICULAR CARTILAGE AND BONE: No full-thickness or near full-thickness articular cartilage defects are identified. No bone marrow signal abnormality is seen.LIGAMENTS: The cruciate and collateral ligaments appear intact. Thickening of the proximal fibers of the ACL may reflect prior injury or sprain. The ACL appears intact.EXTENSOR MECHANISM: The extensor mechanism appears intact.ADDITIONAL
1. Tear of the posterior horn of the medial meniscus with a flipped meniscal fragment as described above.2. Moderate size joint effusion.