Posterior cruciate ligament avulsion fracture

Displaced fracture of the posterior and medial articular surface of the upper tibia is notedseen with adjacent bone marrow oedema. The fracture is at the expected site of the tibial insertion of the posterior cruciate ligament which is retracted.

Knee joint effusion.

The medial and lateral collateral, patellar, and ACLanterior cruciate ligaments are normal. The quadriceps, semimembranosus tendons are normal. The menisci are normal. 

TheHowever, there is peritendinous and intramuscular fluid of the popliteus muscle and haemorrhage/fluid in the popliteal ligament swelling. Knee joint effusionfossa between the popliteus, soleus and medial and lateral bellies of the gastrocnemius muscle.

This case shows a posterior cruciate ligament avulsion fracture with a fracture at the central posterior tibial plateau. The MRI shows alsoJoint effusion and signs of popliteal ligament swelling and joint effusionmuscle injury indicative for a posterolateral corner injury.