I just started physical therapy and I have stiffness in my lower back that makes it hard to stand up straight. I asked my therapist about getting a brace and she said absolutely not. She said they are great for after surgery, but not for teaching your body to stand straight. I was like what???? She explained that the brace will hold you straight but it is not teaching your muscles to do the work. If you wear a brace for an extended period of time, you will in fact do more harm than good. Whataver muscles you are currently using will weaken because the brace will be doing all of the work.
She also explained to me that when you walk all hunched over (she calls it the pain position) it is putting more stress on your lower back and not in your abs where it should be. This is why it is so important to correct your posture when you walk, to take the stress of off your lower back.
Good luck!
10sox