The medial collateral ligament (MCL) is a broad, thick band that runs down the inner part of the knee, from the femur (thighbone) to about four to six inches from the top of the tibia (shinbone).The MCL's primary function is to prevent the leg from over-extending inward, but it also is part of the mechanism that stabilizes the knee and allows it to rotate.
Injuries to the MCL commonly occur while playing sports. The tear can occur as a result of a strong force hitting the outside of the knee that causes the MCL -- and, possibly, other ligaments on the inside of the knee, such as the anterior cruciate ligament (ACL) -- to stretch or tear. In addition, MCL tears occur in sports where there are a lot of quick stops and turns, such as soccer, basketball and skiing. Slipping on ice, if your lower leg splays out, also can produce the same result. Another cause of injury is repeated stress, where the MCL loses its normal elasticity and becomes limp, like a worn-out rubber band.
Initial symptoms of a MCL tear include:
Treatment of a MCL injury rarely requires surgical intervention. Almost always, a period of rest, bracing and physical therapy usually is sufficient to heal the tear and allow patients to resume their previous level of activity. The time before an athlete is able to return to their sport corresponds to the grade of the injury.
On average, it takes six weeks for a MCL injury to heal. The initial treatment for most grade 1, 2 or 3 MCL tears focuses on reducing the pain and inflammation in the knee while immobilizing the knee to keep it stabilized. This includes:
The cast or brace may be designed so that you cannot bend your knee at all. If this is the case, you will need to modify your behavior so that you can avoid having to squat, kneel down or bend over. You should try to keep your leg elevated even if you are sitting in a chair, to reduce blood flow to the knee.
Once the pain and swelling subside, you will begin rehabilitation, which will include exercises to restore strength and normal range of motion to your knee. If your knee feels sore while you are doing these exercises, you should proceed slowly to prevent further irritation.
Once the MCL has healed fully, you should have a minimum of long-term effects, providing there was no other damage to the knee. Recovery times differ depending on the severity of the injury: