I had several blocks (right arm) when I was first diagnosed with RSD. The first three didn't do much for me either. The fourth, on the other hand, helped tremendously. It was a different kind of block that totally numbed my arm because I was having a MUA of my right shoulder. I went to therapy right after and my arm began to improve. I think that numbing the limb completely may have reset something. Just a guess, not sure. Good luck to you . Prayers and soft hugs.