This is great to have thoughtful replies so soon. Thank you all. Today one of my brothers, a longtime physician, introduced me to a friend who is a hand specialist. This is a different doc from the one I saw last week, who gave me a cortisone shot and a wait-and-see prognosis. This latest doc gave a wide range of treatment options I won't bore anyone with unless asked, but interestingly he said to begin with DUCT TAPE. That's right, placed strategically it can support the basal joint with out loss of flexibility or function. If it works, I will move to a custom brace. Still, I plan to modify every aspect of my playing if possible. I like the ideas Tom presented here, both technique and equipment-wise. I am intrigued by the notion of keeping the thumb more opposite 2 and 3, and will try it, though it seems the toughest thing is those passages where the thumb must stretch laterally across the neck, which as far as I know cannot be helped. I have already changed some fingerings of some pieces, and might do more, but some it seems must remain unchanged to keep the integrity of the music . If anyone is interested, I would post some very short playing samples and/or pictures of such passages--maybe some of you have suggestions. Thanks again everyone, I will keep checking in.