I got this.

1) Get the Weisberg book and do the stretch set in there once in the morning and once in the evening:
http://www.amazon.com/Minutes-Pain-F...dp/B000FCK4VS/

2) After you feel some improvements to your body (could be a few days to a few weeks), start walking again. But use a little timer (watch, smart phone, kitchen timer, whatever) and set it to something low like 4 mins. When it beeps, turn back. That's an 8 min walk.

Every couple of days, bump it up by 1 min (for a total of two). You will build up to 30.

You may want to do the Weisberg stretches before and/or after your walk. They are only 3 mins.

Watch out for traction on the arm and shoulder girdle. If you pick up the pace as your fitness increases, this can be a real danger to your TOS. Your two main options are a) keep the arms bent or b) support the arms such as putting them in pockets or even propping loose fists on top of jean pockets.

If you still have back problems there are other books, stretches and exercises that you can do. I also like inversion therapy.

But start with the above and see how you do.