Sports Medicine: Medial Collateral Ligament (MCL) Injury/Tear

What is a MCL injury?

The Medial Collateral Ligament (MCL) is the ligament of the knee that joins the inner side of the tibia (shin bone) to the inner side of the femur (thigh bone). The MCL provides support to prevent excessive motion on the inner side of the knee joint and feelings of instability while walking or running.

What causes an MCL injury?

A common way the MCL is injured is from a direct blow to the outer side of the knee. This can happen in many sports, but most often in football. When the blow occurs, the knee is forced inward, causing one or more of the ligaments in the knee to tear. A non-contact injury of the MCL is also common and can happen with a forceful twist.

What are the symptoms of an MCL injury?

The initial injury may be defined by pain on the inner side of the knee. Usually the knee will swell within 24 hours, causing the knee to become stiff and painful. The swelling, stiffness and pain may last for several days, and it may be several weeks before the knee is stable again. Athletes who are tempted to test the knee too early risk re-injury, with more swelling, pain and stiffness that could prolong the healing process.

How is an MCL injury diagnosed?

Physicians usually diagnose an MCL injury with a thorough history and physical examination. Physicians may order an MRI (magnetic resonance imaging) of the knee to evaluate the damage to the MCL and to look for damage to the joint cartilage or other knee ligaments which may have occurred along with the MCL tear.

What is the treatment for an MCL injury?

Treatment varies depending on the severity of the injury. In mild cases, the athlete will be fitted for a knee brace that allows the knee to straighten and bend, but prevents any stress to the MCL. Rehab may consist of anti-inflammatory treatments and strengthening exercises, progressing to sport-specific exercises. Treatment time in mild MCL injuries usually takes between 2-6 weeks. In more severe cases, the athlete will be placed in a straight leg immobilizer for 2-4 weeks to allow the MCL to heal. After this, treatment will follow that of a mild MCL injury. In the rare cases where the MCL and ACL are torn, a surgical repair of the MCL and ACL may be recommended.

What is the long term outlook for MCL injuries?

Athletes that receive appropriate medical treatment generally have no further issues after complete recovery from an MCL injury.