my back has been hurting since Nov. i went to my dr. and he performed x-rays,blood test ct scan and mri. sd all he could see is .spondylolistesis since then he has put me on muscle relaxers and pain pills and a tens unit. my left sd of shoulder at top and left sd of neck is tsarting to hurt and he ds i needed to go see a back specialist. went to se a back specialist and he sd same thing . sd neck and shoulder are hurtin because of not moving aroung enough because of back pain. he then sent me to therapy which did not help only made it worse. he now recommends i go see a pain management dr. the tens unit helps a lot but that is about the only relief i get. i was told to wear in for a hour and then wait 3 hrs. and put on 2 more times for a hr each day. it feels half way better when tens unit is on but when not wearing it continues to hurt very bad. is there any thing else i can do and how long are you suppose to use a tens unit.