September! If he's had any good days at all that's a miracle! This crap takes a lot of time - and I'm talking years, not months, to adjust. The trick now is to let him know that right now - with that nasty brace around his body - it's the worst it gets. As soon as the bones heal and the brace comes off, you START to get your life back in order. Oddly enough, I too cracked my back in September ('96) and I didn't begin to even go out of the house by myself until January. So just chill and try to put the rest of his life together -> money, housing, possibly some schooling that kind of stuff. Don't worry about 'feeling good' for another few months.
The best place in the States for Stem Cell research is at UC San Diego. They're doing some kick #### stuff, but PLEASE don't make that any kind of priority at all. "The Cure" is not important now and it's nothing you can control. Right now you need to focus as a family on putting his life back together -> Looking at how people actually become happy and productive (chair sports!). Waiting around for a bunch of scientists to make your life better is a losing proposition. Becoming active and healthy is super important. And besides, they are no where near human trials at this point.
His body took a huge hit and it's going to take a LONG time to come to grips with it. Don't be in a big hurry just now. Wait till that damn brace comes off. It's starts turning up hill from there.