i just got back from UPMC and surgery. To quote a resident "it was complicated". seems trauma was the source and I had scarring they had to hack through. Sectioned the nervus intermedius and MVD'd pert near everything else. I have just an 'echo' of the old pain track and that is lightyears better! The side effects are slowly abating and not stabilized yet (unbalance, hearing, etc).
Should it ever have the gall to resurface, I'm right behind you in going thru it again. It's like a new lease on life. Oh, wait, it is a new life.

Let me know how you're doing!