Is it bad to crack your knuckles?
LONDON. September 19. KAZINFORM 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. If you are one of those people who sits and cracks your knuckles while others wince, at some point somebody is bound to have told you that cracking your joints gives you arthritis, BBC informed.
For some it's a nervous habit; for others the sensation brings relief. Depending on which research you read, between 25 and 54% of people do it, with men more likely to do so than women.
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. This gives the space in the joint time to return to its normal size and for more gases to dissolve in the fluid, ready to form bubbles which can then pop all over again.
Taking an engineering approach, cracking the knuckles repeatedly over many decades could in theory damage the cartilage covering the joint. Comparisons have even been made with the mechanical wear and tear accrued over time by ship's propellers, but the evidence that the same is happening in people's hands is thin.
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