Have a look at this question:
What do you do to cure road rash more quickly after a crash?
This question has had problems of its own, but the community should decide if we should give medical advice or not. This has obvious legal implications. Obviously, we need to tell people to see a doctor! (The poster here already has.)
Please, if you agree with someone's opinion, vote it up (or down), and also keep in mind that downvoting in meta doesn't cost anybody rep. Thanks!
Edit: I'd like to clarify that I don't want to exclude medical questions, but I'm concerned about liability issues. Questions about stretching or not, how to keep your fitness level up, and so on, seem quite on-topic to me. I'm concerned about explicitly medical issues -- stuff you really should ask a medical doctor about (or, even better, a sports doctor).
I also don't want to pick on this particular question -- it's a good example of the sort of medical questions we may get in the future.
Edit 2: I started a thread in Meta Stack Overflow about liability.