The medial collateral ligament (MCL), one of four knee ligaments,
connects the thighbone (femur) to the lower leg bone (tibia) along the inside
of the knee joint. It stabilizes the knee joint and stops the knee from bending
MCL injuries often occur during twisting, bending, or quick changes
of direction, such as might happen if a knee is hit from the side while it is
locked in position.
Minor injuries are treated with rest, ice, compression, and
elevation (RICE). Knee movement may also be restricted for a period of time
with a knee immobilizer. Severe MCL tears may require surgery.