LCL sprain

Last Sunday, Robert Griffin III suffered a fairly uncommon knee injury, the lateral collateral ligament (LCL) sprain.  The lateral collateral ligament connects the femur to the fibula on the lateral (outside) part of the knee.  It is smaller and thinner than the medial collateral ligament, and it feels like a small pencil.

Most of the time in football, players are hit on the lateral side of their knee, which places a lot of tension on the medial side of the knee and can cause a MCL sprain (think about breaking a pencil, the side that is getting longer is normally the side that breaks).  The lateral side of the knee is much more exposed which increases the number of MCL sprains.  In order to sustain a LCL sprain, a person would likely have to be hit on the medial side of the knee.  That's what happened during Griffin's injury.  As he was falling to the ground, the defender hit him directly on the medial side of the knee, causing the LCL sprain.  The LCL isn't as critical to knee stability as the other 3 knee ligaments, but for a running quarterback like Griffin, it is a bad injury.  He missed this past Sunday's game and could be out a few more weeks as the ligament heals and he goes through rehabilitation.