12-year-old male patient with left knee injury/pain and swelling. MENISCI: The posterior horn and body of the lateral meniscus are detached from the underlying tibial plateau and displaced superior to the anterior horn. The medial meniscus is intact.ARTICULAR CARTILAGE AND BONE: There is patchy edema within the distal femur most predominantly on the medial and lateral aspects of the medial and lateral femoral condyles. Edema is also noted within the lateral aspect of the lateral tibial plateau and the fibular epiphysis.There is subtle curvilinear low T1 signal within the subchondral bone of the weight-bearing portion of the lateral femoral condyle and slight cortical depression with associated bone edema compatible with an impaction injury. There is low T1 signal and associated edema about the lateral aspect of the lateral tibial plateau which is suspicious for a non-displaced fracture.The articular cartilage of all three compartments is intact.LIGAMENTS: There is a complete midsubstance tear of the anterior cruciate ligament. The posterior cruciate ligament is intact. The popliteus muscle and tendon are intact. The collateral ligaments are intact.EXTENSOR MECHANISM: The extensor mechanism is intact.ADDITIONAL
Findings compatible with a pivot shift mechanism of injury with complete ACL tear, lateral meniscus tear, and associated bone injuries. 