Mutants & Masterminds is an RPG where everyone plays a superhero. My friends and I had never played it before (other than the GM, of course). We started by brainstorming about what kind of superheroes we wanted to make. Not knowing much about the game, I asked if I could play a grandma who can run really fast.
It turned out that description fit into the Speedster build. Long story short, I ended up creating Agatha, a senior citizen who runs really fast and knits snares around enemies. Someone suggested that she might use a walker, with tennis balls on the ends.
My character’s superhero name came from Ellie, who is absolutely fantastic with puns. She suggested the name “Hot Flash”. It made me laugh, and I immediately insisted that the name was now canon.
Hot Flash’s backstory is probably more detailed than it needed to be. She was born with the speed ability. This irritated her mother, who taught young Agatha to knit (hoping the kid would sit still for a while). Hot Flash was 65 when our Mutants & Masterminds game began.
The main thing I want to bring up here is that Hot Flash uses a walker because she has arthritis. Her superpowers don’t erase her disability. She temporarily gains the ability to use her walker to move faster than… well, almost anyone.
There aren’t many stories about superheroes who have a disability. Superman has a severe allergy to kryptonite (but rarely encounters it). Daredevil is a crimefighter who is blind. Hawkeye is deaf in the comics, but I don’t feel like that was made clear in the Avenger movies.
You don’t have to have a disability in order to play a character who has one. Do some research on that disability to learn more about it. Don’t use a superpower to “cure” the disability.