Canadian study explains the sound of cracking knuckles

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ALBERTA, CANADA - Knuckle-cracking; you either love it or hate it! But now some crafty Canucks are claiming they've cracked the case of why joints pop, and you're going to want to hear their explanation.

For many years, researchers couldn't quite put their fingers on it. What is actually making that cracking sound? But recently at the University of Alberta, something clicked. The Canadians put down their maple syrup, they fired up an MRI machine and shot video of someone taking a crack at it.

The university called it the "Pull My Finger" study, but it was no joke! Canadian researchers, reached out to a master-cracker, who they claim is the Wayne Gretzky of knuckle cracking, to lend a hand. The MRI recorded what was going on inside the skilled subject while his joints were jarred. The video shows the "cracking" sound is made when a gas-filled bubble is formed in the fluid that lubricates the joint. The crack happens in a snap, as a vacuum is quickly created between the bones.

The team hopes this research can help them better understand joint health to possibly prevent arthritis in the future. And in case you're wondering, the researchers didn't find any long-term negative effects from cracking knuckles. The worst it can do is annoy the people around you.