By Dr. Mercola
Your joints, including those in your knuckles, are surrounded by a membrane called the synovial membrane, which forms a capsule around the ends of your bones. Inside this membrane is synovial fluid, which acts as a lubricant and shock absorber so your bones don’t grind together when you move.
When you “crack” your knuckles, or any other joint, it expands the space between your bones, creating negative pressure that draws synovial fluid into the new gap.
This influx of synovial fluid is what causes the popping sound and feeling when you crack a knuckle.1 If you continually crack your knuckles, the synovial membrane and the surrounding ligaments will loosen, making it easier and easier for your joints to crack.
More than 20 years ago, I co-authored a paper titled “Cracking down on neck cracking,” which was published in the journal American Family Physician.2 In it, I argued that self-manipulation may lead to lax ligaments. Personally, I don’t think it’s wise to crack your joints on a regular basis, and research suggests it could have some significant repercussions.
Is Cracking Your Knuckles Associated with Arthritis?
The biggest concern most people have about cracking their knuckles is that it could lead to arthritis, specifically osteoarthritis. If you have osteoarthritis, the cartilage within your joints is progressively being damaged, and the synovial fluid is typically reduced as well.
The pain and joint stiffness that you feel is a result of your bones starting to come into contact with each other as cartilage and synovial fluid diminishes. To date, research has not shown a correlation between knuckle cracking and osteoarthritis in your hands.
In one study of more than 200 people, the prevalence of osteoarthritis in any joint was similar among those who cracked knuckles and those who did not.3 The same held true when specific joint types were examined. The authors stated:
"Total past duration (in years) and volume (daily frequency x years) of knuckle-cracking (KC) of each joint type also was not significantly correlated with OA [osteoarthritis] at the respective joint. A history of habitual KC - including the total duration and total cumulative exposure 'does not seem to be a risk factor for hand OA.'"
If you’re interested in lowering your risk of osteoarthritis, it is typically caused by wear-and-tear on your joints along with lifestyle and diet factors, and aging. Repetitive movements often play a role as well, but while it would seem plausible that cracking your joints is also a type of repetitive movement, so far no link has emerged.
Habitual Knuckle Cracking Might Impair Your Hand Function
While cracking your knuckles might not lead to arthritis, it does appear to have other consequences. In a study of 300 people aged 45 and older, habitual knuckle crackers were again not found to have an increased risk of arthritis in their hands. They were, however, more likely to have hand swelling and lower grip strength.4
They also found that knuckle cracking appears to be associated with manual labor, nail biting, smoking, and drinking alcohol… they concluded that habitual knuckle cracking results in functional hand impairment. The damage was likely the result of the repeated stretching and loosening of the ligaments during repeated knuckle cracking.
Interestingly, those researchers noted that cracking your knuckles has been shown to produce “rapid release of energy in the form of sudden vibratory energy, much like the forces responsible for the destruction of hydraulic blades and ship propellers.” This hardly sounds like a completely innocuous habit.
In fact, there are reports in the literature of various injuries that have occurred from knuckle cracking, including overstretching of ligaments in the fingers, dislocated fingers, and a partially torn ligament in the thumb.5
Knuckle Cracking Might Be Linked to Knuckle Pads
Knuckle pads are firm nodules that sometimes form over certain joints in your fingers. They’re often associated with repetitive trauma or movement, and they’ve been known to exist since ancient times (Michelangelo’s statue of David has knuckle pads).6
Knuckle pads are quite common and while they don’t cause physical symptoms, they can have psychological and cosmetic effects. It seems that knuckle cracking may play a role in at least certain cases of this condition.
There is at least one reported case of knuckle pads in a teenaged girl who reported frequently cracking her knuckles daily. In her case, the nodules slowly enlarged over the course of several years, and cracking of the knuckles was listed as the possible cause.7
Are There Benefits to Cracking Your Knuckles?
When you crack your knuckles, the joints become looser and have more mobility for a short period afterward. This perceived positive feeling may be why some people become habitual knuckle crackers.
Another explanation, as reported by one study, is that the movement offers a sort of “therapeutic release.” Chronic knuckle crackers may come to regard the habit as a form of stress relief, although it resembles more of a “nervous habit” like biting your nails (which it is associated with).
Ultimately, there are no significant benefits to cracking your knuckles, and a possibility that it could cause injury or damage to your joints and ligaments over time, so this is one habit that you’re better off without.
If you crack your knuckles and find it difficult to stop, I suggest you to try the Emotional Freedom Technique (EFT). EFT is a powerful self-help method that is very effective for regular stress management as well as for breaking all kinds of addictions, including knuckle cracking. Once the emotional distress is reduced or removed, your body can often rebalance itself and accelerate healing.
Specifically, EFT is a form of psychological acupressure, based on the same energy meridians used in traditional acupuncture to treat physical and emotional ailments for over five thousand years, but without the invasiveness of needles.
Instead, simple tapping with your fingertips is used to input kinetic energy into specific meridians on your head and chest while you think about your specific problem -- whether it is a traumatic event, an addiction, pain, etc. – and voice positive affirmations.
This combination of tapping the energy meridians and voicing positive affirmation works to clear the "short-circuit" — the emotional block — from your body's bioenergy system, thus restoring your mind and body's balance, which is essential for optimal emotional health and the healing of physical disease.
For a demonstration of how to perform EFT, please view the video below featuring EFT practitioner Julie Schiffman. This is a general demonstration that can be tailored to just about any problem. You can also find text instructions and photographs of where to tap on my EFT page.