What does the PCL prevent in the knee?

The posterior cruciate ligament (PCL) plays a crucial role in stabilizing the knee by preventing posterior displacement of the tibia on the femur. When the knee is in a flexed position, the PCL ensures that the tibia does not slide backward relative to the femur during activities such as walking, running, and jumping. This stabilization is vital for maintaining proper joint mechanics and preventing injury, especially during movements that put stress on the knee joint.

The function of the PCL is particularly emphasized during weight-bearing activities and movements that involve sudden direction changes, where the tibia can be pushed backward. This is why the PCL is essential for overall knee stability and function. Understanding the role of the PCL helps inform rehabilitation strategies and treatment approaches for knee injuries, particularly those involving ligamentous damage.