It doesn't happen hardly ever, but I agree with flug on the Asterisk calls. In the last couple of years I've seen way too many major impacts get dusted off and out back in the track, only to find out that they had major trauma.
I do not know of any emerg med pers who aren't watching this racing, seeing some of these crashes, and aren't wanting to collar and board the rider as soon as they've confirmed vitals.
The lawyers for the event must have written some pretty ironclad waivers for the riders (and parents) to sign to be able to avoid litigation.
Tonight's race might be interesting in this regard. I highly doubt that the asterisk crew are licensed up here, so they'd have to engage the services of the locals. Never paid attention to this before myself, but this sort of liability issue up this way can be a real bear if the Ministry gets involved.
I guess your get up and go needs a coffee. - Drif5