kate, have you looked into the tens unit to reduce your pain? its a unit that sends electrical impulses into your body that disrupts the pain signals. if you have not looked into this i would most definitley investigate and try it. your chiro should have info on it. you should be taught by a professional how to use it, but you can buy a unit on ebay for not too much money.
also there are radio waves of a spefic frequency that counter pain signals, but i do not know how one might generate them or if there are therapuetic devices that utilize that technology.