I want to pause here to make something clear: This article is not about superhero comics -- I know for a fact that there are comics that have explored these issues from every angle. I'm talking specifically about the movies that are suddenly dominating the box office and -- more importantly -- dominating the foreign box offices. So now let's talk about how you never see Bruce Wayne taking painful liquid shits in a hospital bed.
While sanitized, epic violence shows up in all PG and PG-13 movies (The Lord of the Rings never shows us a screaming Orc dying slowly due to a gangrenous arrow wound to the scrotum), superhero movies have it written into the reality of the universe: The protagonists simply can't be seriously wounded. In The Avengers, the second funniest scene comes after the credits, when it's revealed that the apocalyptic battle has left the good guys so utterly unscathed that they all go out to eat at a restaurant afterward. They don't even need to shower.
Even in the "gritty, realistic" Dark Knight, when Bruce suffers several falls that should have broken every bone in his body, he is shown to have (gasp!) several bruises on his back and a minor cut on his arm.
Hilariously, Alfred sees this and is taken aback in horror.
"My God ... your one-man war against an army of murderers has left you with the gruesome wounds of a man who has played one game of flag football."
So? What's Wrong With That?
Did you notice something about that scene? Bruce Wayne, at his most wounded and vulnerable, is still sexy as hell. Funny how we never see him suffer the kind of wound that requires him to piss through a catheter for the rest of his life, or have his wife wipe his ass for him because his arms don't work, or get skin grafts to fix oozing burn wounds on his face. The wounds don't in any way interfere with the fun.
"Oh, no, he wasn't fighting crime. That was just the injuries he sustained during routine training exercises."