Hi and welcome Vanessa!
I'm Kate, my rsd started when I was 23, from a blood test injury. I've had it in my right arm (hand, arm, shoulder) for 6 years, and in my right leg for a year. I also get muscle spasms and twitches, and I take baclofen for it. I take 50mg a day.
I've basically taken this for the whole six years (besides during 2 pregnancies

) but was on 25mg daily until about 2 years ago when it was raised up a notch. I weaned off it a few times in these six years, just to see if it was still helping or not, (as I would have flareups and get some cramps and spasms), and found that without it I was TEN times worse- with constant spasms and cramps in my arm and hand, and they were so debilitating, I just couldn't function at all.
So maybe you could talk to your doctor about whether a muscle relaxant may be beneficial for you, if it can work in with any other medications you are on. Sometimes muscle relaxants can clash with other meds, and lower your blood pressure- leaving you dizzy when you stand up etc- and give you other side effects, so make sure your dr says its ok for you.
I hope you can find a way of reducing these spasms etc.
x Kate