Originally Posted by Shinigami
Apparently the mask helped the pain of his wound from the plague or the beatings - some obscure suffering done to Bane. I don't know if it was some kind of morphine, but it might have something to do with how he was able to take so many blows from Batman without flinching.
Does anyone on this forum remember how Bane was beaten in Knightfall? Part one of that story, "Broken Bat" was were he broke Batman's back, part two of that story, is where Bruce passes on the cowl to Jean Paul Valley to be the fill-in Batman, and Jean Paul defeats Bane. In part three, "knighsend" Bruce has to come back and defeat Jean Paul to reclaim his mantle. Anyone remember how JPV defeats Bane? The mask. In the comics, and the cartoons, Bane is addicted to a steriodal (makes his muscles bulge out, and wipes away pain) compound/ poison called venom. The venom is delivered directly to Bane's head via his mask. You can see the contraption clearly here:
On the bottom panel. See those tubes going into his mask, and the contraption he's wearing on his left arm? He pushes a buttom on that arm-control, and it pumps venom into the tubes and into his head. The way JPV defeats Bane is to cut those tubes, thus depriving Bane of the steriod that wipes away his pain and makes him stronger. Nolan didn't go with anything like that in the movie, but some of the ideas were there.
Here's a better look at how the venom system works in the comics, from the back of Bane's head: