Earlier quoted context omitted.
Are you under the impression people without legs just sit around hoping someone will give them a piggyback ride? Oscar Pistorius qualified for the 2012 Summer Olympics without any.
I'm frankly not sure how this is relevant to a survival scenario where people may or may not be injured. Anyway, the entire ISS is built around astronauts using their feet as anchors, allowing them to use their hands for work. Without legs, you wouldn't be able to do maintain your position while working in 0g, hence the challenges of spacewalking. There's plenty of videos where astros show how the top of their feet b…
I fully expect an organization capable of creating the ISS to be capable of figuring out a way for prosthetics to be usable onboard. Put a bit of velcro on one of these, perhaps: https://www.youtube.com/watch?v=a2z8CE2vomY