People who crack their fingers have been given flack for years from non-finger crackers who say it causes arthritis. Recently, however, that myth has been dispelled.
The age-old finger cracking mystery apparently comes from a bubble forming in the fluid within the joints when bones separate – NPR called it “a tiny air bag inflating.”
This discovery, found in a study conducted by Plos One, aligns with the original study conducted in 1947. However, the 1947 study was then challenged in the 1970s.
According to Greg Kawchuck, a professor of rehabilitation medicine at the University of Alberta, the second group to conduct the finger-cracking experiment believed the noise was caused by a gas bubble collapsing.
Although many people believed in the bubble popping theory, no one could confirm it. For this reason, Kawchuck and a team of scientists banded together to put the question to rest, with the help of a friend who was exceptionally adept at cracking his knuckles.
“We called our colleague the ‘Wayne Gretzky of finger cracking,’” Kawchuck joked. “He can make this happen in all 10 of his fingers.”
In order to solve the mystery, they asked the volunteer to place his hands inside of an MRI scanner and created a film of them as he pulled on each finger to make it crack.
“We’ve been calling it the pull my finger study,” Kawchuck said.
The scientists discovered that the popping sound spawns from a bubble that forms between each joint, not when it erupts. This study also reinforces another study that challenged the thought that cracking knuckles causes arthritis.
“It’s mostly an urban myth perpetuated by mothers who are sick of hearing their kids crack their knuckles,” Dr. Kevin DeWeber, who studies sports medicine in Vancouver, Washington, said. In fact, DeWeber believes cracking the knuckles might even be good for the joints, serving as a type of massage.
For the finger crackers everywhere, rest assured that nothing harmful is happening to your joints, but instead, possibly something helpful.
Information taken from npr.org and plosone.org