NSW Premier Mike Baird fractured a vertebra after slipping down the steps at his Manly home in the middle of the night.

Mr Baird posted an X-ray of his fractured vertebra on Facebook and Twitter, anticipating the jokes that would follow.

And they did, ranging from the obscure to the political. For the most part, though, commenters on his Baird back were polite, and few were disc-hurteous.

On his Facebook page, he wrote: "Note to self: when fetching a glass of water late at night, don't walk down the stairs in your socks with the lights out."