Advice post collision->police->hospital

In short, the question is: is it possible to instigate damage claim procedures with only a number plate registration?

Yes a solicitor or the cycle organisation that provides you with insurance (if you have it) can access the information.

For example, when I was in my car a couple of months back, a car went in the back of me and they refused to exchanged details. I have reported them to the police but my insurers could instantly tell me the details of the owner and that they were insured. My insurers are now pursuing a claim against them and the police are investigating.

I think there is also a DVLA database that you can access somewhere too.