Does cracking your knuckles cause arthritis?

Cracking your knuckles is not known to cause arthritis. Several medical centers describe the warning as a myth, and the studies that compared habitual knuckle crackers with people who did not crack their knuckles found no difference in arthritis rates. A Tufts Medical Center orthopedist called the idea an old mothers' tale meant to get children to stop. A hand surgeon at Northwell Health said knuckle cracking can never lead to arthritis. [1] [2] [3]

The pop involves gas in the synovial fluid, the fluid that lubricates joints. Pulling the bones apart, by stretching the fingers or bending them backward, lowers the pressure inside the joint. The traditional explanation is that bubbles form and burst. A 2015 study suggested the sound may instead come from the formation of a gas-filled cavity. Either way, the sound is gas-related, not cartilage tearing or bones grinding. Because the gas takes time to dissolve again, the same knuckle usually cannot be cracked again for about 15 to 20 minutes. [4] [3] [2]

Harvard Health reports that several studies compared rates of hand arthritis among habitual crackers and non-crackers and found no higher risk in the crackers. Johns Hopkins Arthritis Center likewise noted that limited studies showed no change in arthritis occurrence between the two groups. Tufts describes a California physician who cracked the knuckles of one hand daily for 50 years and left the other alone; X-rays showed no difference in arthritis between the hands. A 1990 paper reportedly found more inflammation and swelling in people who did not crack their knuckles. Tufts adds that family history is a better indicator of future arthritis. [1] [5] [2]

Sources differ on whether the habit has other downsides. Harvard Health and Johns Hopkins mention a study suggesting reduced grip strength after many years of habitual cracking. Cleveland Clinic says an older study suggested weaker grip and more hand swelling, but that 2017 studies found no damaging effect on grip strength, swelling or range of motion. [1] [5] [4]

Injury is a separate concern. Pushing or pulling too hard could dislocate a knuckle or injure a ligament, and Johns Hopkins and Harvard cite a small number of case reports of such injuries. The University of Washington notes that repeated injury or swelling of a joint can damage cartilage and potentially lead to degenerative joint disease, though it says there is no evidence that cracking itself causes arthritis directly. Pain, swelling, limited motion or crooked-looking fingers are reasons to see a healthcare provider, and a painful sound may reflect an existing joint problem rather than ordinary gas release. [4] [6] [5] [3]