Cracking your knuckles: What really happens inside your joints?

15 abril 2015

«Pull my finger,» a phrase embraced by school-aged kids and embarrassing uncles the world over, is now being used to settle a decades-long debate about what happens when you crack your knuckles. Scientists have determined what happens inside finger joints to cause the distinctive popping sounds heard when cracking knuckles. For the first time, they observed that the cause is a cavity forming rapidly inside the joint.