Pros and Cons of Cracking Your Knuckles

Knuckle, from the Middle English knokel, is the part of your finger at a joint where the bone is near the surface. Knuckles are handy. You can knuckle down, knuckle under, be a knuckle dragger or a knucklehead, and give someone a knuckle sandwich. Knuckles are great for rapping on windows and your sister’s head to get her attention.

Knuckle cracking is the act of bending or pulling your fingers to produce a popping noise. Here’s how it works. A thick clear lubricant called synovial fluid surrounds all the joints in your body. When you stretch or bend your finger to crack your knuckle, the bones in the joint pull apart. That reduces the pressure on the synovial fluid and bubbles form that expand and burst causing a popping noise. It’s kind of like what happens when you open a can of soda.

Habitually pulling your joints beyond their normal physical range is not that good for them. Ligaments and joints aren’t intended to be stretched over and over like that. Doctors generally agree that if you crack your knuckles for years it can damage the soft tissue in your joints and reduce the strength of your grip.

On the positive side, there's evidence of increased mobility in joints right after you pop them, although the short-term benefit probably isn’t worth the potential long-term damage. Oh, and just for the record, there’s no scientific evidence that cracking your knuckles causes arthritis.

Many people are irritated by the sound of popping knuckles. Others could care less. With that in mind, here are a few considerations when the urge to crack hits you.

Knuckle Cracking Dos and Don’ts

  • Refrain from cracking your knuckles—or any other joint for that matter—if someone around you doesn’t like the sound. 
  • Avoid trying to crack your joints a second time for at least 30 minutes. It takes that long for the gas from the bubbles to re-dissolve into the joint fluid. Your joints won’t make the popping noise again until then. 
  • Try stretching your fingers to relieve writer’s fatigue instead of cracking them. Ah-h-h-h, that feels good… 
Consider This: Not everybody’s joints pop. Some people have too large a separation between the bones. Others can’t relax enough to allow the bones to separate.  Read more about habits like cracking your knuckles.