Torn anterior cruciate ligament. I could not use my left leg to go up or down stairs. That leg could not really hold my weight well at all. I was told by an orthopedic surgeon that surgery was absolutely necessary, that a ligament cannot heal because it gets no blood supply. The Chi machine helped a lot. I put it on my knee everyday for 2 weeks. I never had surgery and I am now able to do Tai Chi as well as walk upstairs.
-Mary G Arana (Charleston, SC)