You’ve likely heard the warning from a concerned parent or friend, “Don’t crack your knuckles or you’ll get arthritis!”
Although there hasn’t been a ton of research in this area, all of the studies show that there is NO CORRELATION. People that have cracked their knuckles habitually for decades have no greater chance of developing osteoarthritis than those who have not!
Despite the sometimes very loud sounds that come from this practice, the process of knuckle cracking is pretty harmless. There is some suggestion that habitual knuckle crackers may have increased likelihood of inflamed joints, or possibly some reduced grip strength. But these potential risk factors are mild at best.
*WARNING* The following paragraph contains technical jargon:
Actually, knuckle cracking is very similar to a chiropractic adjustment. Both involve instantaneous stretching of the connective tissue capsule that surrounds the joint. This stretching increases the volume and thereby decreases the pressure inside the joint. This decreased pressure produces gas bubbles which burst when the pressure drops low enough. Keep in mind that these gas bubbles were already dissolved in the synovial fluid of the joint before the knuckle cracking event, and after the bubble bursts, the gasses are re-dissolved in the fluid again. It takes several minutes to re-dissolve, which is why you can’t repeatedly crack the same joint over and over without a recovery period.
The benefits of knuckle cracking include the joints feeling more mobile, and the positive neurological stimulation of the stretch receptors. It also comes with that oh-so satisfying sound and the annoyance of one’s mother. In a somewhat comical experiment, Dr. Donald Unger has spent the last 60 years daily cracking the knuckles of one hand while leaving the other alone to prove to himself and others that it doesn’t cause arthritis. The verdict? Both hands are normal.