One kid in teh LM cult was bitching about it, and that's all I've heard.
From what I gathered in my research on it when I heard of it, is that you should take yoga, no strenuous high-impact excercise (such as running, skiing, it sucks, I know), and eating WELL.
Also, take up rock climbing for good excercise that won't kill you.
Basically, you're an HIV patient without the dying part. Think of it as a good excuse to live a completely healthy life. It sucks that you're gonna have to quit skiing if it gets too bad, but you should definitely enjoy the time you have left to ski, and make sure you keep up with a healthy lifestyle. It'll extend the amount of time you can ski.
Also, I've heard that spondyloarthritis gets alot better in your later twenties, cuz it's mostly a juvenile disease so be hopeful.
I put the STD in STUD, and all I need is U!