I've started wearing a knee brace and have been working at strengthening the muscles around my legs to help improve with my knee pain that i've been experiencing from getting old. The brace somewhat helps, although it might just be psychological.
Another thing that I have tried is to get warmed up real good before hitting the slopes, that has helped me with the pain a bit as well. Hope that helps you!
If your board is in perfect condition at the end of the season, you're doing it wrong!