Cracking your knuckles causes arthritis.
This is a MYTH. (Well, mostly.)
For all you perpetual knuckle-crackers out there, it may come as a relief to learn that every satisfying “crack” is unlikely to up your chances of developing arthritis, despite how many times your mother may have warned you otherwise.
But your mother may not have been all wrong, either about knuckle cracking and arthritis. 
Expert answers on this subject tend to be inconclusive, but that’s due to a relative lack of studies on the effects of knuckle-cracking. However, it’s medically unlikely that it can cause arthritis.
Still, none of this goes to say that you shouldn’t try to kick the habit. Apart from the debatable politeness of public joint-popping, studies show that it can damage the tissue and ligaments around the joint and lead to increased incidence of hand swelling and dislocation, as well as lowering the strength of your grip.
