Here I'm thinking of "heroes" as characters who occupy central roles in a series or story, rather than support characters. As for what "differently abled" means, I imagine everyone will have his/her own definition.
One interesting if gimmicky hero was the 1947 RACKMAN from Hillman Comics. He was a dwarf who wore a device beneath his clothes called a "rack" that created the illusion that he was six feet tall. I think he may be the first starring comics-hero to use an artificial enhancement to make up for a physical shortcoming , but others may care to weigh in.