I tried it for Sugar's back end weakness, and it was literally a lifesaver for her. Her condition was (in my layman's understanding) a degeneration of the vertebrae which pressed on and/or exposed the nerves. She was nervous at first, but got used to it, and would just lay on her blankie for the procedure. It worked so well for her I started getting it for my arthritis, and it works great for me too
I know it doesn't work this well for everyone, but I always think it's worth a try!