It’s a familiar—if sometimes jarring—sound. It’s that snap, crackle, and pop that occurs when you manipulate your knuckles or twist your spine. Sometimes it happens spontaneously when you flex your ankle just walking down the stairs. The sound can be somewhat alarming, but what’s really going on inside those noisy joints?
“There are a number of theories, but no one knows with 100 percent certainty,” admits Carrie Bowler, an osteopathic physician in One Medical Group’s Wall Street office in New York. The most accepted theory, according to Bowler, is that the joint releases a gas when it’s under stress from certain movements. Pressure on the joint causes the release of that gas, which results in that familiar popping sound.
Like so many events within the body, popping joints vary tremendously from person to person. Some people creak and crack with practically every movement, while others can’t make a sound even if they try. “Every body is unique,” explains Bowler. “Just as some people’s muscles are tight and others’ are hyper-flexible, some people’s joints are quiet and others’ make a lot of noise.”
Knuckle Cracking Not Linked to Osteoarthritis
Your mother may have warned you against deliberate knuckle cracking—instilling fear of deformed joints, stiffness or even arthritis. Thankfully, it seems that science has proven Mom wrong on that one. In a recent study published in The Journal of the American Board of Family Medicine, researchers examined the possible connection between knuckle cracking and the development of osteoarthritis—the most common form of arthritis—in the hands. After studying X-rays of subjects ranging in age from 50 to 89, the researchers found that the incidence of osteoarthritis was similar among those who crack their knuckles and those who don’t. They concluded that having a history of habitual knuckle cracking didn’t seem to increase one’s risk of developing hand osteoarthritis.
Still, Crack with Caution
But when it comes to deliberate, and sometimes forceful, cracking of other joints—like your back or neck—Bowler does urge caution. “If you introduce a lot of force, you could strain a muscle or other soft tissues around the joint,” she says. When a trained professional, such as a chiropractor or osteopath, does the cracking for you, the approach is much different. “They use exact movements with the intention of realigning your body’s structure at the joint they’re addressing,” she says. A joint that routinely cracks on its own (like an ankle or wrist) isn’t a cause for concern, however. The exception would be if it becomes painful or swollen—that, Bowler advises, would warrant a visit to your care provider.