Constantly cracking your knuckles?
A cracking question we get asked in the clinic almost daily is:
“My [Insert body part] cracks when I move it in this particular way, is it bad for me and will it cause arthritis?”
The short answer is no. There are a few different types of noises our bodies and joints produce, but the most common is the harmless “pop” or “crack” (cavitation) you hear, like when you crack your knuckles (seen in this Video MRI). This is as a result of a rapid change in pressure in the fluid between your joints (the synovial fluid) that results in dissolved gases being pulled out of the fluid and forming a cavity. This is what is thought to create the “crack”. This cavity then quickly dissipates and leaves more room for movement to occur (hence why your joint feels looser/free). Within 15-20 minutes the environment in the joint returns to normal (homeostasis) and you are able to crack the joint again.
Will cracking my knuckles cause Arthritis
No. There have been many studies comparing crackers to non-crackers and rates of arthritis have been similar in both groups. The most recent being a study in 2011 tracked 215 adults aged between 59-80 for 5 years and concluded no link between knuckle cracking and hand osteoarthritis (Deweber, Olszewski, Ortolano R, 2011).
Another noteworthy study was performed by Dr Donald Unger (pictured), a GP who only cracked the knuckles in his left hand for 60 years, results showed no arthritis in either of his hands.
What about other noises?
Other types of noises such as rubbing or grinding, also known as ‘crepitus’, can be a sign of damaged cartilage, pathology or tendinopathy.
If pain accompanies your cracks, or your cracks are more grinds and rubs its best to have them checked out by a health professional/physio. Alignment, stability and strengthening exercises often help to decrease the noises and put your body in the best condition it can be!
Deweber, K., Olszewski, M., & Ortolano, R. (2011). Knuckle cracking and hand osteoarthritis. J Am Board Fam Med, 24(2), 169-174. doi: 10.3122/jabfm.2011.02.100156
Disclaimer: Cracking your neck does carry some risk. The vertebral artery runs through the cervical spine up to the brain and it is possible to cause compression or damage to this artery if a manipulation is too energetic, or performed on the wrong person (this can lead to stroke or even death). These risks need to be communicated and your physio should perform tests to identify the likelihood of arterial insufficiency.