Penny -- whether or not the ancient Greeks had wheelchairs as we recognize them, I'm not so sure. But as one of my fellow BADD bloggers pointed out, the ancients of many cultures did have chariots, and there's a good possibility (as far as I know, not backed up by "hard" evidence) that the mobility impaired could have used chariots as their "assistive tech" as needed. King Tut (who had weak bones thanks to family inbreeding and walked with canes) is certainly shown doing all his hunting from a chariot, in the tomb paintings.