This is the moment an amputee skier carved down a snowy slope—swooping side to side on one leg like an absolute pro. Wendy Gideon, 42, is a congenital amputee, meaning she was born without a leg.

JJ Haselbarth doesn’t remember the accident. He remembers the sound of the jaws of life cutting through the driver’s side door of his wrecked car. He remembers the EMTs injecting him with drugs to ...