A responsible pain clinic will give you a trial before they give you a permanent stimulator. They can test to see if you're going to be responsive to this type of therapy before you have surgery. I was tested and it was determined that a simulator would not be helpful to me. I was then tested by having a spinal tap where tiny amounts of Narcotics were leaked directly into my spinal fluid. This proved to be very successful so I had an intrathecal pain pump and catheter installed surgically in my abdomen with a catheter running up my spine. Search these haunts for wsh66 I've written extensively about the pain pump. For me, it was the way to go. Very pleased.