Lifestyle

Cracking Your Knuckles Probably Won’t Give You Arthritis. One Doctor Tested It on Himself for 60 Years

By Curtis Jones · October 23, 2026

Plenty of us grew up hearing that cracking your knuckles would give you arthritis. The research says that warning does not hold up, though there are still a few reasons to go easy on your fingers.

The myth. Cracking your knuckles wears out the joints and leads to arthritis in your hands.

The fact. Harvard Health says knuckle cracking probably won’t raise your risk for arthritis. That is the conclusion of several studies that compared rates of hand arthritis in habitual knuckle crackers and people who did not crack their knuckles.

The doctor who used his own hands. The best known test came from Dr. Donald L. Unger, a California allergist. According to the Los Angeles Times, his mother warned him as a child that the habit would cause arthritis. So from his teens on, he cracked the knuckles of his left hand at least twice a day and never cracked the knuckles of his right hand, which served as a control.

He published his findings in the journal Arthritis and Rheumatism in 1998. In 2009, at age 83, he received the Ig Nobel Prize in medicine, a lighthearted science award, for cracking the knuckles of one hand every day for more than 60 years. “I’m looking at my fingers, and there is not the slightest sign of arthritis in either hand,” Unger told the Times. One person is not a scientific sample, of course, which is why the larger studies matter.

The bigger studies agree. A 2011 study in the Journal of the American Board of Family Medicine looked at 215 people aged 50 to 89 who had hand X-rays. Hand osteoarthritis was about as common in knuckle crackers (18.1%) as in people who did not crack their knuckles (21.5%). Even people who had cracked their knuckles the longest and most often did not have higher rates. The researchers concluded that habitual knuckle cracking does not seem to be a risk factor for hand osteoarthritis.

What the pop actually is. Harvard Health explains that the sound comes from gas in the synovial fluid, which lubricates the joints, when the bones are pulled apart. A 2015 study that filmed finger joints with real-time MRI found the crack happened as a gas cavity formed inside the joint, rather than when an existing bubble collapsed.

The grip strength question. A 1990 study of 300 patients aged 45 and older found no more hand arthritis in knuckle crackers, but they were more likely to have hand swelling and weaker grip. Harvard Health says chronic cracking may lead to reduced grip strength. Cleveland Clinic notes that later studies from 2017 did not find that effect, so the evidence is mixed.

When to pay attention. Cracking itself should not hurt. Cleveland Clinic warns that pushing too hard or bending a finger the wrong way could dislocate a knuckle or injure a ligament, and Harvard Health notes published reports of injuries from trying to crack knuckles. If cracking causes pain, or you notice swelling or a finger that looks crooked, Cleveland Clinic advises seeing a health care provider.

The bottom line. If you crack your knuckles gently and it doesn’t hurt, the research suggests your joints are not paying for it later.

This article is for general information and is not medical advice. Talk with your doctor about joint pain or swelling. This article was produced with the assistance of AI and fact-checked against the sources cited by LightWave Reports.