As per Fight Times Magazine, the amount of external force that must be applied to dislocate the knee (a very serious injury) is probably around 80 – 100 pounds per square inch.
The knee is the largest joint in the body and is also the most complicated. It is a modified hinge joint, and contains synovial fluid.
The knee joint connects the two longest mechanical levers in the human body, the thigh and the lower leg. As a result, large forces act in and around the joint, contributing to its instability. Stability is mainly provided by the ligamentous structures.
Three bones articulate at the knee joint: the femur, tibia and patella (commonly referred to as the knee-cap).
To learn more about knee structure, see Fight Times Magazine.
Check out these 7 Tips for Healthy Bones shared by some experts from Cleveland Clinic.