66-year-old female with significant ecchymosis and hemarthrosis. Evaluate MCL, ACL, MPFL, patellofemoral articulation. Due to patient's body habitus, the high-definition coil could not be utilized resulting in slightly suboptimal image quality. MENISCI: There is globular signal abnormality within the body and posterior horn of the medial meniscus that appears to extend to the free edge, indicating intrasubstance degeneration with degenerative tearing. The anterior horn appears spared. There is globular signal abnormality within the body of the lateral meniscus, which extends to the free edge, indicating intrasubstance degeneration and degenerative tearing. There is intrasubstance degeneration affecting the posterior horn of the lateral meniscus.ARTICULAR CARTILAGE AND BONE: There is focal discontinuity of the cortex along the medial aspect of the patella which we suspect represents an avulsion fracture at the site of attachment of the medial patellofemoral ligament. There is mild edema within the underlying medial aspect of the patella as well as mild edema within the anterior aspect of the lateral femoral condyle likely reflecting prior transient patellar dislocation. There is full-thickness cartilage loss along portions of the lateral facet of the patella. The medial facet of the femoral trochlea appears abnormally small relative to the lateral facet, likely representing dysplasia. The trochlear depth appears shallow. There is focal depression of the articular surface of the medial femoral condyle just above the posterior horn of the medial meniscus that may represent an old impaction injury, but this is not associated with edema on this examination. There are small tricompartmental osteophytes.LIGAMENTS: The ACL, PCL, and LCL appear intact. There is a small amount of edema along the medial collateral ligament which may represent a mild sprain, but the ligament itself appears intact. EXTENSOR MECHANISM: The quadriceps tendon appears intact. There is mild increased signal intensity within the medial fibers of the patellar tendon at its patellar attachment, suggesting a sprain injury. The medial retinacular structures are ill-defined with adjacent edema indicating injury. As stated previously, we suspect there is an avulsion fracture of the medial aspect of the patella at the attachment of the medial patellofemoral ligament. The ligament, including its femoral attachment, is not well visualized. There is also slight thickening and edema along the lateral retinacular structures, although we see no gross disruption.ADDITIONAL
1. Findings indicating prior transient lateral dislocation of the patella, including disruption of the medial patellofemoral ligament and probable medial patellofemoral ligament avulsion fracture at the medial aspect of the patella. There are also findings of femoral trochlear dysplasia.2. Possible mild sprain of the MCL which otherwise appears intact. The ACL appears intact.3. Full-thickness cartilage loss along the lateral facet of the patella.4. Degeneration and degenerative tearing of the menisci.5. Joint effusion and Baker's cyst.