What Happens When You Crack Your Knuckles?
You might say that good news has popped up in recent years for people who find it soothing to crack knuckle joints.
Scientific research hasn’t come to a firm conclusion about what happens when you pop your knuckles. However, one thing that recent research indicates is that the cracking doesn’t cause arthritis.
Instead, two studies in 2015 shared the conclusion that knuckle cracking seems to improve range of motion. Also, researchers in both studies question the results of 1990 research showing that knuckle cracking may cause swelling and loss of grip.
Studies About Knuckle Cracking
PLOS-One published the University of Alberta study Real-Time Visualization of Joint Cavitation in April 2015.
Dr. Gregory N. Krawchuk of the University’s Department of Physical Therapy led the Canadian team, which used magnetic resonance imaging (MRI) to record what happens during knuckle cracking.
University of California (UC) Radiologist Dr. Robert Boutin and Orthopedic Surgeon Dr. Robert Szabo, who teaches surgery, conducted the second study. They presented it in December 2015 at a Radiological Society of North America meeting.
The U.C. study used ultrasound imagery, which a December 2015 article in Science Alert cites as being 100 times faster than MRI at capturing images. It notes Dr. Boutin as asserting that ultrasound also captures images ten times smaller than MRIs can.
Boutin and Szabo saw bright flashes similar to fireworks in ultrasounds as study participants cracked joints. The bursts seemed to occur before a bubble developed in the protective synovial fluid.
A Mystery Remains
Science Alert reports both studies concluding that changes in synovial fluid correlate with the sound and popping feeling of cracking knuckles. But it notes a what-came-first mystery.
The publication recounts a 1947 theory that the popping sound of knuckle cracking occurs when a bubble forms in joint fluid. Decades later, other researchers said the sound likely comes from the bubble bursting.
Science Alert noted that the University of Alberta study agrees with but doesn’t prove the burst bubble theory. In contrast, it stated, the U.C. researchers support the 1947 theory.
Information to Relieve Fears
Although the bubble theories are unresolved, Science Alert reports that both the 2015 studies found “no immediate pain, swelling, or damage being done to joints as they were cracked” and that no clear difference in arthritis results exist between those who pop and those who don’t.
Whatever the cause, joint pain remains an uncomfortable reality. If it is a problem for you or for a loved one, it’s a good idea to reach out to an orthopedic hand specialist.
Please contact us at Southeast Orthopedic Specialists. We can help you feel better and share facts instead of myths.