49-year-old female with right knee pain. MENISCI: There is globular increased signal abnormality within the posterior horn of the medial meniscus indicating intrasubstance degeneration. There is blunting of the free edge of the body of the lateral meniscus suggesting fraying or perhaps a small tear. There is a small focus of intermediate signal along the undersurface of the posterior horn of the lateral meniscus which likewise may reflect a tiny tear, but the clinical significance of this finding is uncertain.ARTICULAR CARTILAGE AND BONE: There is edema within the medial aspect of the patella as well as within the lateral aspect of the lateral femoral condyle likely representing bone contusions from prior transient patellar dislocation. The cortex along the medial aspect of the patella is indistinct which may reflect an avulsion fracture, although the fracture fragment is not discretely visualized. There is flattening of the femoral trochlea, superiorly, indicating dysplasia. There is also slight lateral translation of the patella relative to the femoral trochlea. There is a 13 mm ovoid focus of signal abnormality within the posterior aspect of the distal femoral metaphysis likely representing a benign enchondroma. There is deep fraying of the articular cartilage of the lateral facet of the patella with at least one full-thickness cleft. There is a small full-thickness defect of the articular cartilage of the lateral aspect of the femoral trochlea. There is mild heterogeneity of the articular cartilage of the lateral tibial plateau that may represent mild degeneration. The articular cartilage of the medial compartment appears intact.LIGAMENTS: The ACL appears intact, but is slightly thickened with fluid signal intensity along its proximal fibers which may represent a ganglion. There is an approximately 1 cm ovoid focus of low to intermediate signal intensity along the anterior fibers of the ligament that may represent focal arthrofibrosis. The MCL appears intact, however, there is extensive edema along the medial supporting structures of the knee indicating retinacular disruption and likely tearing of the medial patellofemoral ligament, the femoral attachment of which is not visualized. Edema extends posteriorly along the posterior oblique ligament which may be sprained. The PCL appears intact. The LCL appears intact.EXTENSOR MECHANISM: The quadriceps and patellar tendons appear intact.ADDITIONAL
1. Findings indicating prior transient lateral patellar dislocation.2. Blunting of the free edge of the body of the lateral meniscus may reflect fraying or a small tear.3. Articular cartilage degeneration/tearing as described above.4. Thickening of the ACL may reflect mucoid degeneration or perhaps prior injury with an ovoid focus of signal abnormality along the anterior aspect of the distal fibers which may represent focal arthrofibrosis.5. Other findings as described above.