Actually, as I recall, Bruce was primarily healed by the time that whole thing went down. By the end of Knightquest, Bruce was walking with a cane, but had lingering health effects. Kinsolving's heal was just a quick and easy way to speed up his recovery to get him back in costume.
Really, in terms of medical science, Bruce and Barbara's injuries were apples and oranges. He still HAD a full spinal cord, it was just bruised.