When I "broke my tailbone"

the doc explained that the three bottom bones are fused and that at the joint above the bone moves either forward or back. The fix for it is for it to go back in place. The skelaxin can relax the muscles and allow that to happen. Because of the pain you hold muscles tight trying to prevent it which defeats what needs to happen. If it doesn't reset itself they may reset it for you -- he said rectally.
Skelaxin is not a pain reliver I would take something over the counter to help with the pain. Also if you can stand someone to gently rub it if it is flipped forward this may help it ease back into place.