If a friend told you cracking your knuckles causes arthritis, they might have just been searching for a nice way to get you to stop the habit.
The truth is, there is no connection between cracking your knuckles and arthritis – or any other long-term health problem.
When you crack your knuckles, the popping noises, or “crepitus,” result from gas bubbles in the fluid that helps lubricate your joints. The bubbles pop when you pull the bones apart, either by stretching the fingers or bending them backward. It releases some endorphins that help reduce pain, but otherwise, it’s thought to be a harmless habit that doesn’t signal any type of health problem.
– Eric M. Ruderman, MD, professor of medicine, associate chief, clinical affairs, Division of Rheumatology, Northwestern University Feinberg School of Medicine, Clinical Practice Director, Rheumatology, Northwestern Medical Group