Of course, at the same time, DC has created a universe where it makes absolutely no sense at all for [Barbara Gordon] to not be able to walk.
That’s the problem with bringing in “realistic” elements into super-hero stories. As much as I’m all for using events like the ones in Killing Joke to build characters and spin into something new — which is exactly what they did with Oracle — there’s also the fact that Barbara Gordon lives in a world where people have access to phenomenal sci-fi technology from alien worlds and super-advanced societies, Purple Healing Rays, Green Lantern Rings, Lazarus Pits… The list goes on for days, and that’s without even bringing up how Bruce Wayne recovered from his own paralyzing spinal injury by having his psychic girlfriend/physical therapist think really hard at his back. That happened. And they live in the same town.
”—Chris Sims, discussing Barbara Gordon’s return as Batgirl in the DC Relaunch (source)