Cracking sounds on your joints can definitely sound—if not feel—alarming. It's probably happened to all of us, though, whether from cracking knuckles on purpose or just hearing popping sounds when stretching. I talked to a few medical experts to find out what's going on and whether or not all this noise is a sign of a medical issue. Here's what they said.
It's Usually Harmless The common misconception that cracking your joints will cause arthritis is just that—a misconception. Dr. Levi Harrison, an orthopedic surgeon and the author of The Art of Fitness, says he's often asked this question. He explains:
Commonly, joints make an audible cracking sound when the joint is stretched or manipulated due to gas inside the joint fluid or synovial fluid. Common gases in the joint are O2 (Oxygen) and N (Nitrogen). When you flex and stretch your fingers in order to "crack your knuckles", the capsule around the joint which contains this gas filled fluid causes the bubbles to burst which causes that sound. The sound may be loud or dull. Often, you have to wait a period of time before the sound can be heard again, if you manipulate the joint. It takes time for the gas bubbles to reform in the joint.
Dr. Michael Haley, owner of Agape Chiropractic, offers a few more insights —and strange medical terms (joint mice? crepitus?!) that describe the issue:
Sometimes the sounds are coming from muscle bellies. Other times they are coming from the deeper joint structures - tendons, ligaments, and discs. Sometimes the sounds aren't "cracking sounds" at all, but rather, inflammation in the joints that is "squishing around" with movement. These are the noises someone might hear continuously when they turn their heads side to side. Ideally, turning your head does not make any noise. Joint mice may contribute to the sounds. These sounds are collectively usually referred to as "crepitus".
Based on clinical experience, it seems that tension builds up and allows for the joints to "crack" or release. Inactivity seems to increase the need... whereas frequent movement and stretching seems to not only decrease the need, but also even the possibility of of cracking the joints.
An interesting observation is that humans learn to disobey their need for movement. Cats and dogs seem to stretch out their bodies, with an emphasis on their spines, after every period of inactivity. Kids seem to stretch after inactivity too. But adults tend to get up and go about their sedentary days. No wonder their joints crack... or need cracking…
In other words, it's a good idea to fit more movement into your day, if you're not already doing so.
When You Might Want to Consult a Doctor Those assurances aside, there are times cracking joints is more ominous. If you experience any pain with the cracking, it could be a sign of a medical problem. Dr. Harrison says:
Individuals who have painful grinding and creaking joints that started after an injury or trauma to their joints may have arthritis. This is not a good thing. Arthritis occurs when the protective cartilage lining of a joint has been damaged or eroded. This can occur from an injury, age, or an even inflammatory condition like rheumatoid arthritis.
If you have had an injury, for example to your hips or knee and experience significant hip and or knee pain, as well as popping of your joints, you may have arthritis in these areas. I recommend an evaluation by your healthcare practitioner. After an appropriate history and physical exam, they may order the necessary radiographic tests to evaluate the joint. Arthritis is common and pain with creaking and popping in any joint warrants proper evaluation by your doctor.
In the absence of pain, though, you probably don't have to worry (but can check with your doctor if you're still anxious about this). Dr. Harrison doesn't recommend cracking your knuckles, neck, or anything else, but it's still probably harmless. Consider this research noted by Dr. Amy Baxter, CEO of MMJ Labs (which makes a really cool pain blocker, Buzzy):
One really fun paper was what we call an "n of 1" study - some guy (Dr. DL Unger) decided to only crack one hand his whole life, and see what happened. He then published the result. Bottom line: the cracked knuckle was bigger, but none the worse for wear.
I also asked my sister, a family physician in Arizona, about this, and she said she gets this question a lot—strangely from young teenage patients. Her advice? It's probably nothing...but if it bothers you, stop cracking your knuckles or neck. So there you go.
