This bit explains about how the diagnostic procedure works.
The good news is that although I'm somewhat tender around there because of the injections, they've dealt (so far) with some of the really nasty pain. That argues strongly for facet joint degeneration being at least part of my problem, which fits reasonably with the symptoms. Certainly if the relief keeps up for a couple of weeks it's really quite strongly indicative.
What that means is that Richard and I will likely have to discuss the possibility of frying the nerve roots by radiofrequency heating. It's a generally safe procedure, but there are risks.
No, I'm not going to do an LJ Poll on whether I should go for it or not :D Just wanted to keep those of you who are interested in the medical/surgical aspects of my little problem up to speed.