What's the old table made out of? Can you cut the legs off to the right heigth?
I've got carpal tunnel/tendonitis, too. The pain comes and goes and so does the tingling in my fingers. There are times when I can't even hold a fork to feed myself without putting the fork down and shaking out my hand.
Something I do is a little excercise; I stretch my fingers backwards, in the opposite direction that makes them tingle. However, when I use the computer mouse too much, there's nothing I can do about that. The gel pad doesn't help much there, either. Sometimes, all you can do is go ahead and have the surgery. It's getting to that point with me. Not about to give up my computer, my painting, hand sewing, stringing beads, etc!!
Wishing you the best in whatever you decide to do.
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Psalm 119:105 Thy word is a lamp unto my feet, and a light unto my path.