Many people believe cracking knuckles can cause arthritis. But does it really do so? Several studies have been conducted so far and no one could reveal any significant relation between knuckling and development of arthritis.
Some people crack their knuckles by pulling the tip of each finger one at a time until they hear a crack. Others make a tight fist or bend their fingers backwards away from the hand, cracking the lot at once. Whichever method is used, the noise is created in the same manner. The space between the joints increases, causing the gases dissolved in the synovial fluid bathing the joint to form microscopic bubbles. These bubbles merge into large bubbles which then get popped by additional fluid which rushes in to fill the enlarged space.
Once the joints have been cracked they can’t be cracked again for about fifteen minutes. OK, but could cracking your knuckles cause other forms of damage? There are isolated reports of accidental self-inflicted injury from knuckle-cracking, with injured thumbs and sprained finger ligaments, but these are rare.
So if you like cracking your knuckles then by all means carry on, but just bear in the mind it might be annoying for the observer.