question: I have chronic back pain. My doctor implanted a neurostimulator and 5 days after implanting it they turned it on and programmed it to relieve the pain in my lower back and it was working great. After a few days it no longer seemed to be effective even if I turned it all the way up I could barely feel it and I was getting excruciating head aches. Also the stimulation is no longer in my back it is in the front of my knees and thighs. Do you have any idea what could be causing this? My doctor doesn t seem to know