What is the ACL and why is it important in the knee?

The knee joint is supported by four main ligaments that hold the joint together, with the primary stabilizer being the anterior cruciate ligament (ACL). The ACL is named such because it orginates toward the front of the inside of knee (anterior) and crosses with the PCL (cruciate).

Being the main stabilizer of the knee, the ACL is therefore at the most risk of injury when the knee is put in a compromising position. The main movement of the knee is flexion and extension, but as we know with most sports and higher level activities there are varying degrees of rotation and side to side movements that are needed in order to make complex movements. Unfortunately these complex movements can put a lot of stress on the ACL, especially if there is poor control in the muscles around the knee that act as secondary stabilizers.

The most common mechanisms of injury for the ACL involve being hit from a force on the outside of the knee or with twisting motions. To try and minimize rotational motions at the knee hip strength is important as these muscles help to control the knee in space. Single leg stability or balance is also very important so that the muscles in the leg can turn on fast enough to stabilize the knee during rapid movements.

Here are two exercises that can be easily added to your workout routine to try and help prevent ACL injuries. Always consult a medical or exercise professional before starting a workout program.