Hunter's Canal is an area that dives behind the knee that allows the femoral artery to travel up through it and it's protected by some overlying tendons. A study from 2008 by the tourniquet god himself, Dr. John Kragh, showed that tourniquet efficacy dropped to about 67% when tourniquets were placed over Hunter's Canal.

If you go from the knee joint itself, up about 15 centimeters that's where that canal lies. I've placed the tourniquet above the joint but I'm still below that marking. so what I need to do is take that tourniquet and place it higher up on the thigh for it to be fully effective. So remember when placing a tourniquet around the knee you can either place it two to three inches above the source of bleeding.

We never want to place it over a joint directly and then if we're going to go above the knee make sure you give yourself a good 15 centimeters to avoid Hunter's Canal and get the most bang for your buck when placing that tourniquet.