5 Things You Need to Know About MCL Tears of the Knee

1. The MCL Is on the Inner Knee

When you are standing with both knees facing forward, the medial collateral ligament (MCL) is on the inner part of the knee, towards the other knee. It is a broad, flat ligament--really a thickening of the joint capsule. This is in contrast to the ACL, PCL and LCL, which are more rope-like structures.

2. Buckling of the Knee Can Injure the MCL

When the knee buckles inwards and becomes more knock-kneed, that is a valgus position. This will stretch the inner portion of the knee and tear the MCL. This can occur with any sort of contact sport, where the knee is hit on the lateral portion. Being tackled in football, getting legs entangled in soccer, getting hit in the air and landing awkwardly in basketball, or getting a ski caught and falling to the side are all situations that put the MCL at risk.

3. Most MCL Tears Heal on Their Own

Because the MCL is such a broad structure, tears of the ligament have a large surface area to heal. With so many fibers touching and overlapping, chances are that the MCL will heal by itself. Contrast this with the other main knee ligaments (ACL, PCL, LCL), which are more discrete structures, more cord-like: When they tear, there is less surface area for the ends to contact and they tend not to heal as well by themselves.

4. Use a Brace to Prevent Further Injury

Because football linemen are constantly having people fall on their knees, you now see pretty much every lineman wearing hinged knee braces. The struts on the side of the brace prevent side-to-side motion, which would tear the MCL. A hinged knee brace can also protect the ligament while it is healing. The hinge allows for range of motion, while preventing valgus loads on the knee. Typically, an MCL tear takes about 6 weeks to heal.

5. Surgery is Rarely Necessary

Typically, surgery for the MCL is reserved for those people who didn't heal by themselves. These usually are higher grade injuries. Another subset of people who may require surgery for their MCL tears are those patients with multi-ligament knee injuries. These typically are higher energy injuries and cause gross destabilization of the knee joint.