You’re never going to look at the uncle who asks you to pull his finger at your next family get-together the same way again. Because now it’s actually scientifically cool to pull your finger. At least that’s the conclusion we’re drawing after the University of Alberta released a new study late last week, one that’s lovingly being referred to as the “Pull My Finger Study.”
In it, lead author Greg Kawchuk (a professor in the Faculty of Rehabilitation Medicine) and Nanaimo, B.C. chiropractor Jerome Fryer wanted to discover what it actually looks like when someone pulls your finger. So they filmed Fryer — a master finger cracker in his own right — having his fingers pulled inside of an MRI machine, hoping to answer the age-old question of why your joints crack.
What they discovered is that when the joint was pulled far enough apart, it created a gas-filled cavity where the joint-lubricating substance synovial fluid sits, acting like a vacuum to create that infamous cracking or popping sound.
“As the joint surfaces suddenly separate, there is no more fluid available to fill the increasing joint volume,”Kawchuk said in the report. “So a cavity is created and that event is what’s associated with the sound.”
The theory of why the joints crack isn’t new, but this is the first time it’s been recorded in an MRI. Now, the challenge lays in discovering the benefits or harms associated with finger cracking in general, and what it means for a person’s overall health.
“It may be that we can use this new discovery to see when joint problems begin long before symptoms start,” Kawchuk said. “That would give patients and clinicians the possibility of addressing joint problems before they begin.”
Check out the video for yourself, along with one of master cracker Fryer, below.