Illustration of a tear of the posterior cruciate ligament in a rear view. Ruptures of the posterior cruciate ligament are less common than ruptures of the anterior cruciate ligament. These can be caused, for example, by a direct blow to the front of the knee or by a fall on a bent knee. Such a rupture occurs only in rare isolated cases - very often other structures of the knee are also damaged in this case. Note: The distance from femur to tibia/fibula has been increased in the image for better visibility of the cruciate ligaments.