https://www.sideeffectspublicmedia.org/tags/knuckles knuckles en-US Copyright Wed, 15 Apr 2015 20:59:00 GMT https://www.sideeffectspublicmedia.org/trends-times-old/2015-04-15/why-knuckles-crack A little MRI video seems to settle the decades-old debate about that loud pop of the joints: It's all about bubbles. But imagine an air bag inflating, not the bursting of a balloon. Wed, 15 Apr 2015 20:59:00 GMT https://www.sideeffectspublicmedia.org/trends-times-old/2015-04-15/why-knuckles-crack Rob Stein