Snap Crackle Pop

Okay so everyone probably already knows this one, but I am still getting some ugly looks, and there are a lot of rumors circulating, so let's just put it to bed once and for all.

[drumroll please...] What's behind a cracking joint?

Why yes, now you ask, I have been feeling the teensiest bit stressed, and my fingers and neck sometimes crackle under the pressure.  And while it may sound ooky and unpleasant, there's no evidence that it's (a) giving me arthritis, (b) swelling/ enlarging, or (c) gradually immobilizing my joints.  Hurrah!

There are several possible causes for what exactly is making that unseemly noise, which I shall now lay out for you.  The primary postulate is that the snapping sound is the sound of gasses being released from between joints.  I don't particularly want gassy joints, so I'm all for this theory.  Apparently there are fluid-filled cavities in the spaces between bones, and when these are stretched, squished, or contorted, air is rapidly released with a pop.  Like my mom cracking her chewing gum. This is the most accepted explanation, but a couple others are noted - and for the sake of completeness, I'll note them as well.  Firstly, scar tissue or ligaments scraped quickly across protruding bones might make a raspy snapping noise (argh bad!)...something like a rubber band being snapped, I'd imagine.  Or, ligaments stretching quickly might make a noise (as you can imagine); so, too, would actually breaking the connective bits between bones.

I'm not sure about these other explanations, though.  While I'm sure they would be noisy, they would also most likely be painful, and I'm not experiencing any pain at all.  In fact, twisting around in my chair between physics problems has quite a "palliative effect"...so I'm going to treat joint cracking as the equivalent of an ossean antiflatulent.