I could imagine if they went with your original idea, but then Wilt would probably be relegated to being a supporting character since he'd be chair-bound, watching basketball games in the living room all day.
There was a special hwere it shows Wilt getting all his injuries. His creator grew up to be a big basketball player but before that he was a child bullied on hte court by his big brother and his imaginary friend. Then as they were playing a game his brothers Imaginary Friend attempted to foul the boy physically but Wilt used himself as a shield and took a lot of injuries. It still costed the boy the game and Wilt was so upset ofr letting the boy down he ran away to fosters.
I may or may not be wrong about this, but I read somewhere that the inspiration for Wilt being an amputee came from Craig seeing a dog with an injured leg that never healed, or something along those lines.