Unless there's something else going on with your hand like carpal tunnel, it should relieve some of the pain, but not all of it. You WILL still need your pain medication. I don't know how much, if ANY, pain relief you're going to get. Some people get quite a bit while alot of others get none. I should think you'll be able to use the arm/hand again as once they release that nerve, you shouldn't have a problem. But the pain receptors have been irritated for so long, they're gonna keep shooting out pain signals. So that's why you're going to need your pain meds.

I don't blame you for not wanting surgery because sooner or later you'll need more down the line. But looks like you have no choice right now. Best of luck and God bless. Keep us posted when you're up to it. Hugs, Lee