I'm not up on any survivors having to deal with amputations, but it wouldn't surprise me in the least. I would hazard a guess that whether or not somebody had to deal withit would have as much to do with luck as getting the affected limbs and digits warmed up. The problem with frostbite is that when the tissue freezes, the crystalization of the water does a number on the cells...often rupturing cellular walls and killing the cells in the really severe cases.
When the tissue is killed, gangrene sets in and amputation becomes necessery to save the victim's life.
You can find out a bit more about it by going
HERE and
HERE.