Aww, I'm so sorry to hear that the brace didn't produce the desired outcome and that you have all this uncertainty to deal with now. I've seen lots of posts from you over the last year or so that I've been reading that document just how much of a strain that brace has been to him and how resolute he's had to be -- it must be so difficult as a parent to see him not benefit for having gone through all of that.
When they ask about pain level don't forget about C, the chronicity constant. It's a little known constant, the sum of how long it's been going on + number of past failed treatments + number of stupid comments recently made by well meaning people (such as myself). You take the physical discomfort level at that moment, and multiply it by C for the actual discomfort level.
All attempts at humor aside: I feel like I've gotten to know you and your son just a bit reading all your posts, please take my heartfelt wishes for his surgery to come up very soon and then be over with and for it to do what it's intended to do.
Polly