Ahed Bseiso took a step forward. And then another. Her hands held the walker and her eyes were trained downward, watching her left foot advance — and then her new right foot, which followed in a careful, slightly stilted rhythm. She’d learned a short time earlier how to navigate the prosthetic leg, needing only a few moments supported by a set of parallel bars before she lifted her hands and took tentative steps forward. She was at an Englewood prosthetic clinic, its walls covered in photos of smiling people playing softball or golfing with their prosthetics.