Well, he absolutely lost his hands, that much is for sure, and doesn't seem that broken up about it. (Edit: Correction, he didn't at first.)
As for how it hasn't been discussed publically as far as I can tell, but he's flat out denied that it was intentional.
http://archive.li/BhN4f
Some comments absolutely are not having it, though.
Whatever happened, for it to affect both hands from the wrist on either has to have been intentional or some kind of crushing accident involving his hands, since it's doubtful he accidentally got frostbite on both hands in the middle of summer in Nevada.
Edit:
Seems a lot of people are echoing an apparent comment he made (that I can't find) where he was icing his hands with dry ice to deal with arthritis, then fell asleep. I find this hard to believe, especially that it was done with two hands at the same time, in a way that led to so much damage they had to be amputated.
He either used way too much ice all at once (that shit evaporates at room temperature) or he did something stupid along with using dry ice in the fucking first place.
Edit 2:
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