mewsg, sorry for your recent diagnosis.

I have been getting 2 injections in my sacroiliac every 3-4 months for 5 years. I have RSD in both my feet, ankles, & lower legs. Without those I might have lost my sanity before now. But it definitely is not a cure. I still use a cane, (and a wheelchair for long walks/shopping), I don't wear shoes or socks just sandals & moccasins in winter when necessary but I use Lidoderm patches to ease the pain, I'm limited in the amt of walking I can do daily, I soak in Epsom salts every day at least once, I take 3 mg muscle relaxers daily, 5-7 nights in a week I'm awakened in a flare (voltaren gel helps), cannot be in direct sunlight, etc, etc, etc ....those injections allow me to have a life but as you can see they are not a cure.
The important thing is that the dr's aim is good. Fluoroscope guided. In 5 years I've had only 3 bad reactions, but I still got relief even with bad side effect that wear off in a couple of weeks. At the time of my last injections in May I rated my pain @ 15-20. It was consuming me. But my neurologist had been out of the country.
I had received the depo medrol injection before RSD for bursitis, tendinitis and such so I knew they brought relief but it isn't instant, relief comes on slowly for me. Now they do put Lidocaine in so there is some immediate relief but it seems to wane quickly for me.
I might add, I'm an old woman that might make a difference.