Is It Bad To Crack Your Knuckles?
Is cracking your joints bad for you? This is one of the most frequent questions that we encounter as physiotherapists and we have heard several old wives tales relating to the potential damage that this is causing. The same can be said for any other joint that cracks or pops. In this blog we will set the record straight as to what causes the popping sound heard in joints, if it is harmful and when you might need to a physiotherapist to investigate.
So what is the mechanism behind joint cracking?
Researchers have been investigating this topic since 1947 when Roston & Haines used X-ray images to examine the moment that the cracking sound occurred in the knuckle joint. It was proposed that the formation and collapse of a bubble within the synovial fluid lead to the audible cracking sound.
As medical imaging continues to advance their initial hypothesis has been challenged and corrected slightly, with the most recent major study conducted in 2015 by Kawchuck et al., using real time MRI imaging. This study concluded that the cracking sound is characterized by rapid separation of joint surfaces with subsequent cavity formation, which can be seen beside the arrow in the image below.
Is it bad to crack your knuckles?
This change in pressure can cause the joint to feel more free and can result in a short term reduction in pain or sensations of stiffness, however homeostasis occurs after around 20 minutes and the joint returns back to its normal pressure.
Why do my joints crack when I've been resting?
This is once again caused by bubble formation in synovial fluid when there is uneven pressure. When we are inactive certain joint spaces can experience a build up in pressure, which is rapidly changed and equalized when we initiate movement. This is the reason that the sound may be worse first thing in the morning or after a prolonged period of sitting and usually decreases after a few steps.
Is this bad for me?
The joint cracking described above is a natural phenomenon and has not been shown to cause any damage to the joint surface. Many studies have looked at the rate of osteoarthritis between people who do and do not crack their knuckles, with no significant difference between groups. A 2011 study found that within a group of 215 participants there was no significant difference between those who do (18.1%) and those who do not crack their knuckles (21.5%).
It must be taken into consideration that we are discussing pain free joint cracking, if you experience pain during or after a joint cracks you should speak to your physiotherapist for further advice.
Cracking joints is not associated with arthritis.
How can I stop the joint from cracking?
Generally speaking, the best way to prevent a joint from cracking is to keep it moving. A joint that becomes stiff is more prone to the pressure changes that contribute to the cracking sensation. By remaining active we can ensure that the joint movement is smooth. There is conclusive evidence that supports the use of physical exercise for managing osteoarthritis, so keep it moving!
What if I am not 100% sure that this noise is safe?
The information above relates to a specific event that occurs in the joints following a change in joint pressure, however other noises made by the body including grinding, clicking and rubbing can be a sign of joint instability, cartilage degeneration, tendon rubbing or soft tissue injury. These sensations are potentially a more serious issue and should be thoroughly examined and diagnosed by a physiotherapist. Once diagnosed your physiotherapist can explain the cause and discuss a management strategy for your condition.
Are your joints cracking? If you begin to notice any abnormal or painful sounds or sensations, book an assessment with one of our expert physiotherapists below. Servicing Niddrie, Essendon, Airport West, Keilor & Melbourne’s Northern suburbs for over 40 years, you can book with one of our expert physiotherapists below or call 93794557 to speak to one of our admin superstars.
References
Deweber, K., Olszewski, M., & Ortolano, R. (2011). Knuckle cracking and hand osteoarthritis. Journal of the American Board of Family Medicine : JABFM, 24(2), 169–174. https://doi.org/10.3122/jabfm.2011.02.100156
Kawchuk, G. N., Fryer, J., Jaremko, J. L., Zeng, H., Rowe, L., & Thompson, R. (2015). Real-time visualization of joint cavitation. PloS one, 10(4), e0119470. https://doi.org/10.1371/journal.pone.0119470
Roston, J. B., & Haines, R. W. (1947). Cracking in the metacarpo-phalangeal joint. Journal of anatomy, 81(Pt 2), 165–173.
Article by
Shaun Tamraz | Physiotherapist
Shaun graduated with a Science degree from the University of Melbourne in 2016. Following a Gap year in Europe, Shaun returned to complete his Bachelor of Applied Science and a Master of Physiotherapy Practice at La Trobe University, graduating in 2020.