I have very little feeling in the left side of my right thumb, I had no feeling for years as I chopped up the nerves at the base of my thumb ohh about 23 years ago. Now I have a sort of tingly feeling, which is a bit weird. Sort of like how your mouth feels when it is beginning to come out of the anesthetic you get at the dentist.
Got to say, you learn to live with it just fine.
My Dad chopped part of his thumb off with a circular saw a load of years ago too, and had it stuck back on. Sounds like the same sort of area as you. Again, he just lives with it fine. Apart from the fact that it wasn't a great job they did putting it back on, and it sticks out a bit too much, it doesn't bother him and he does a load of fine engineering stuff.
So, for my money, if you are happy with the job so far - live with it, it isn't that bad. And it can be a great party trick sticking pins in your dead bit
Come to think of it, I also have that same tingly feeling down part of my left arm and hand from a spinal nerve thingy.
In the end, the diving wouldn't make my decision, but the possible problems later in life. I know that I can live happily with no feeling in bits of my hands. If the chances of success were good - maybe I would go for the op, but if the chances of success were borderline, I would rather live with no feeling, than pain.
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