Depends what you are looking for? Are you looking for answers concering insuring the kitesurfgear? Or are you looking for infomation concering unjuries to yourself (selfinflicted) or others?
Normal insurances don't cover kitesurfing related injuries (typicalle they cover kites up to 1,5mtr). there are however insurances that do cover it, you'll need a special kind of extremesportsclausule, which most companies do not offer, however Sportzeker.nl and funsportpolis DO offer coverage, they also included the coverage of kitesurf and/or other sports that are labelled 'extreme' by insurancecompanies. Those insurances also cover, to some degree, injuries/damage done to other persons.
As to our national healthcare goed: injuries that have been caused during kitesurfing are being covered by you healthcareinsurer, but thats for direct treatment only, so disability etc are not covered by those healthcarepolicies. the two insurancecompanies i mentioned before DO offer those kinds of things.
PS: I'm not a lawyer, I have a soul