Flash, one thing you might want to look at is either a TENS or a Muscle Stimulator. I have 2 TENS units that are infinitely programmable, then late last year I got a new version, called AvivaStim XP, (muscle stimulator). The first two I've had for years and will basically do everything the last one will. (Although the last one has ONE programmed TENS mode built in it.)
The only real difference is what the programmed stimulation modes are. Muscle stimulators tend to have lower frequency modes, from 5Hz up to maybe 50Hz. Where a TENS will allow you to run from 2Hz up to 150Hz on most 'pre-programmed' modes yet still change the band width within those modes and amplitude (via knobs like volume knobs).
Some days it's the difference between making it and not. Others.... nothing helps. Can't argue with what they do though. But if you're given a choice, I'd look for a highly programmable TENS. (Although right now a I type I've been running the AvivaStim in it's second 30 minute cycle.)