We have those here too, but, I use a heating every night and my back is burned, discolored, etc., plus heat doesn't really do anything for it anymore...gotten to the point where Vicodin 750's barely make a dent in the pain.
But, I'm ahead of the game, as I was told when I was 20 I stood a good chance of being in a wheel chair by the time I'm 35...just turned 36 so...