I get that every few months, though I'd describe it a bit differently: First of all, it is usually brought on by sitting hunched over and breathing shallowly f

I get that every few months, though I'd describe it a bit differently: First of all, it is usually brought on by sitting hunched over and breathing shallowly for a while (like, an hour). And the pain isn't exactly stabbing, unless you're counting being poked hard with a Popsicle stick. It releases if I breath deeply enough, with an odd crunching sensation, sort of like popping really small bubble wrap, or cracking knuckles on a tiny hand.