Acute complete rupture of the posterior cruciate ligament. The anterior cruciate ligament is intact. Rupture of the posterolateral knee joint capsule with extensive blood fluid products tracking in the soft tissues behind the knee. There is an oblique predominately longitudinally oriented split in the medial collateral ligament proximal portion with adjacent oedema. The majority of the medial collateral ligament is however intact including the deep meniscal attachments. Fibular collateral ligament is intact and there is no significant posterolateral corner injury. There is an acute horizontal oblique tear of the medial meniscal posterior horn extending from the tibial surface through to the meniscal periphery. The meniscal root attachments are preserved. Lateral meniscus demonstrates some contusional signal near the anterior root attachment. Hyperextension osteochondral impaction injuries seen involving the lateral femoral condyle and anterior aspect of the lateral tibial plateau, including a subchondral nondisplaced fracture of the lateral femoral condyle anteriorly over a 1.8 cm length. Patellofemoral cartilage is preserved. Moderate sized knee joint effusion. No Baker's cyst. No loose body identified.