I am not surprised that you don't have a deffinative dx yet. If you have a couple of operations, they can always call it Failed Back Syndrome. Bad joke.

Don't be concerned about getting an scs at your age if the trial gives you relief. You need to remain functional. If it gives you this and helps keep the pain meds to a minimum you will be amoung the blessed. Take it one day at a time and stick around here for support. Best wishes.