Is Cracking Joints Bad for You? Why Do Joints Crack? | Almanac.com

Is Cracking Joints Bad for You? Why Do Joints Crack?


Why Do Your Knuckles Crack?

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Most of us know folks who intentionally and constantly crack their knuckles (necks, backs, wrists, etc.). Ever wondered some folks crack their joints more than others, if it's helpful or harmful, and how to avoid popping those joints? Let's get cracking on some answers . . . 

Is Cracking Your Joints Bad For You?

Let's get the main question out of the way. Luckily, the consensus among the medical community is: normal joint-cracking does NOT cause arthritis nor harm, no matter how often or for how long you do it. The old saying that cracking knuckles will give you arthritis is an old wives' tale.

However, the clinical literature does contain a few reports of knuckle-cracking causing injury to ligaments or tendons, swelling in the joint capsule, or gradual weakening of the grip. And, obviously, if you feel pain or swelling, a trip to your doctor may be warranted.

But even if habitual joint-cracking doesn’t injure your joints, it can annoy others to the point of straining relationships with family members, friends, and co-workers. If you can’t curb the practice at work, it can have negative effects, too.

Compulsive knuckle-crackers often lose awareness of their habit. If others keep mentioning that it bothers them, or if you have only recently become aware of how annoying your habit is to others, seek help from one of the many websites offering tips on breaking bad habits; ask for help from a close friend or family member; or consider getting help from a licensed therapist.

Why Do Joints Crack?

What we do know is that knuckles are full of fluid which keeps the bones from grinding on one another. Think of the fluid as a lubricant. This fluid contains gasses: mostly carbon dioxide but also oxygen and nitrogen. When the bones separate, there's a drop in pressure in the joint which creates little gas bubbles. 

However, what causes the sound is up to a little debate. One, older theory is that the collapse or popping of these bubbles in the joint makes the sound. Another newer theory says that the bulge appears in the knuckles when you're cracking them, and the bubble creates some kind of pressure wave in the fluid which produces a sound.

The answer? Scientists figured out that the first theory seems true; it's the bubble collapsing that makes the popping noise though the bubble does not have to completely collapse to make the sound. Their next step is to record they need to record the entire process from start to finish and see if bubble formation (not just collapse) contributes too. Oh, the things we do to find out what makes us tick!

  • See this brief video of what really happens when a knuckle cracks.

What Causes Joints to Crack More Often?

Grating, popping, or cracking sounds may also occur under a variety of circumstances, especially when:

  1. You make a sudden change to the joint's position
  2. Tight muscles release, allowing joints to snap back to their usual position
  3. Cartilage wears away, exposing joint surfaces that rub and grate against each other
  4. When ligaments or tendons move over bone surfaces.
  5. Repetitive movements or exercises at the gym which can indicate that your muscles are tight which causes friction around the bone.

As you can tell, many of the reasons joints start to crack more often are related to our bodies aging.

Why Do People Intentionally Crack Their Joints?

Some folks say joint-cracking relieves tension, boredom, or pain, often emerging as a childhood coping behavior. But mostly, they say, it just feels good. So good that it becomes habitual to the point where many people have difficulty stopping. One commenter in an online forum for joint-crackers (no kidding!) identified himself as a recovering opioid addict who'd found that knuckle-cracking released the same burst of pleasure as a hit of heroin, albeit much briefer.

How to Stop Cracking Joints

If your habit bothers you, the main way to avoid the issue is to get moving!! Movement is your body's way of lubricating itself. This means:

  • Gentle stretches in the morning
  • Warming up before and after exercise
  • Avoiding long periods of repetitive movements like weeding
  • Not staying in one position for more than 20 minutes; get up and stretch your body, walk, get a drink.
  • Even while sitting, gentle rotate your neck and head, your ankles, and wrists.
  • It never hurts to drink plenty of fluids. Hydration aids joints.

Now we know! What do you think of this?  Know any knuckle-crackers? Or, are you one yourself?

About The Author

Margaret Boyles

Margaret Boyles is a longtime contributor to The Old Farmer’s Almanac. She wrote for UNH Cooperative Extension, managed NH Outside, and contributes to various media covering environmental and human health issues. Read More from Margaret Boyles

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