Cracking your knuckles will give you arthritis when you get older. That’s probably something you’ve heard at least once in your life, likely from your mum, concerned that your fidgeting habit will give you arthritis.

Well, a number of studies have been done over the years to find out the long-term impact of cracking your knuckles and currently there’s no substantial evidence that shows knuckle cracking leads to arthritis.

So, it’s a myth. Cracking your knuckles does not cause arthritis. (Sorry mum).

As for the “crack” or “pop” noise you hear after you crack your knuckles, it’s not bad either. When you bend or pull your joints, it creates a space within the joint capsule, sucking in synovial fluid. This causes gas bubbles in the joint fluid to collapse or burst. It’s a bit like blowing up a balloon and then stretching the walls of the balloon outward until it pops.

Even if knuckle cracking doesn’t cause arthritis, there’s still good reason to let go of the habit. Chronic knuckle-cracking may lead to reduced grip strength and there are at least two published reports of injuries suffered while people were trying to crack their knuckles.

One of the most convincing bits of evidence suggesting that knuckle cracking is harmless comes from a California physician who reported on an experiment he conducted on himself. Over his lifetime, he regularly cracked the knuckles of only one hand. He checked x-rays on himself after decades of this behaviour and found no difference in arthritis between his hands. A larger study came to a similar conclusion. 

What really causes hand arthritis?

The two main types of arthritis found in the hand are osteoarthritis and rheumatoid arthritis. 

Osteoarthritis

The most common type of arthritis, osteoarthritis involves wear-and-tear damage to your joint’s cartilage; the hard, slick coating on the ends of bones where they form a joint. Cartilage cushions the ends of the bones and allows smooth joint motion, however significant cartilage damaged can result in bone on bone contact causing pain and reduced range of movement. This wear and tear can occur over many years, or it can be hastened by a joint injury or infection.

Rheumatoid arthritis

In rheumatoid arthritis, the body’s immune system attacks the lining of the joint capsule, a tough membrane that encloses all the joint parts. This lining (synovial membrane) becomes inflamed and swollen and as the disease progresses cartilage and bone within the joint can become destroyed.