I have CRPS in my arm as well and I have done every option out there....including about 12 different drugs. I have had the injection and it did absolutly nothing for me. It is very frustrating. The sps is the next option for me. I am hesitant to do it but as the doc told me it really isn't doing anything but blocking out the crossed nerve signals. My arm already has crossed and messed up nerves. I would however stay away from the Cymbalta....this was the cause of my CRPS.