What Is A Collateral Ligament Injury (MCL and LCL)?

Knee ligament sprains or tears are fairly common sports-related injuries. Athletes that participate in contact sports such as soccer or football are more likely to injure the collateral ligaments.

Your knee ligaments connect the thigh bone to your lower leg bones. The medial collateral ligament (MCL) and lateral collateral ligament (LCL) are found on the sides of the knee.

Similar to other parts of the body, injuries to the ligaments are called sprains and are graded on a scale of 1-3 for severity.

The Grades are as follows:
Grade 1: The ligament is mildly damaged and it has been stretched, but is still able to stabilize the knee joint stable.
Grade 2:  The ligament is stretched to the point where it becomes loose. This is commonly referred to as a partial ligament tear.
Grade 3: Commonly referred to as a complete ligament tear in which the ligament has been split into two separate pieces and the knee joint is unstable.

The MCL is injured more often than the LCL. Due to the more complex anatomy of the outside of the knee, a patient who injures the LCL often injure other structures in the joint as well.