he really broke it? he could have died.. right?
I very much doubt it. If he had broken his neck, at the very least he'd be in one of those big support collars for weeks and that would have been noticed.
My guess is that strain+hyperbole = broken.
A human head masses about 5Kg. So hooning around like that would have made his head weigh about 65N sideways, with sudden loading and unloading of the weight as he cornered. That's quite a strain on neck muscles.