It hasn't really been exploited yet because although it may be the fetish of a handful of people, most people would find it disturbing, gross, sad and wrong.

That aside, I think blood plus had a character with a missing leg, EF had a character with (assuming) missing eye and elfen lied had a quadriplegic girl, only ones I can remember off the top of my head, I usually try to avoid shows that would have such things.

I'm also interested but I think it's considered guro so there isn't much appeal like >>759 said.

Silly Yotsuba, you don't even know who Obama is.

This is only slightly related, but if you haven't read it yet you're missing out.

http://shii.org/knows/Nurse-kun