Preventing injuries

[bodhitree]

I know it is impossible for martial artists to prevent all injuries but what are some of the injuries you've received that could have been prevented? I want to dig into the collected wisdom of kfm ers here. At a local jiu jitsu club a guy broke his arm from being taken down. This influanced one of the places I train (Pitt grappling club) to make breakfalls to be a part of every warm up. The proper way to fall can benefit every martial artist.
One reoccurring injury I have is with my neck, and it is most preventable. Any time I lose my warmup (period of inactivity) and then go back to exercise I hurt my neck. By staying warmed up and loose I can avoid this.