Been going 14 years and only have had one really bad time, knock on wood. Fractured patella, ACL tear, and meniscus tear all in one go. I was 16 when it happened so I bounced right back, but now I'm really paying for it. Anytime it's cold or the weather changes is agony. A few concussions scattered about as well. I think I hurt my hip at some point too, since it really acts up in the cold as well, but I can't remember any time when I really pulled it or anything.