Why is cracking one’s knuckles (and other joints) so addictive?
Why Knuckle Cracking is Fascinating
There are two types of people in this world — the knuckle (and perhaps back, neck and other joint) crackers who indulge in this habit on a regular, if not daily basis, and those who have to put up with it.
Joint crackers defend themselves by saying that they find great satisfaction or even release in pushing, pulling or bending fingers, knuckles or other joints until they pop.
While onlookers tend to find it either a) revolting, b) unnerving, c) plain annoying or d) all of the above.
The thing is, nothing those in this camp say seems to make a difference to those who choose to revel in this joint cracking therapy. Neither do dire warnings from friends and family that a lifetime of cracking could damage the joint. Instead, those poppers just keep on popping.
What Causes the Popping Sound When You Crack Your Knuckles?
After nearly 100 years of mystery and various theories, we seem to be getting closer to a definitive explanation for the distinctive noise produced by the cracking process.
That’s thanks to curious École Polytechnique graduate student, Vineeth Chandran Suja (a veteran knuckle cracker) and Dr Abdul Barakat, who together developed mathematical equations to describe the sound of knuckles cracking.
Their findings, which were published in the journal, Scientific Reports, confirmed that each joint is lubricated by synovial fluid. The presence of this fluid helps to facilitate optimal joint/bone movement and comfort.
Suja and Barakat compared a recording of popping sounds from the model joint that had a bubble in its surrounding fluid with the noise from their own knuckles and found that the two were very similar.
The pair concluded that the knuckle cracking sound comes from a partial collapse of bubbles in the synovial fluid.
Why Do People Crack Their Knuckles – And Is It Harmful?
That’s the big question.
Well, a combination of nervous habits and stress relief could be part of the picture.
But, it’s believed that joint manipulation also stimulates nerve endings* and this action relaxes the muscles surrounding the joint, so crackers may feel momentarily more mobile in that joint.
In the hands of an expert, research has proven that manipulation and mobilization are likely to reduce pain and improve function (this is especially the case for patients with chronic low back pain). But when left to the self-proclaimed crackers, overly forceful cracking can injure the joint.
Habitual knuckle-cracking has been rumoured to cause the onset of arthritis. However several studies have failed to demonstrate a solid link.
For example this late 1998 study, which saw one doctor crack his knuckles on his left hand at least twice a day for 50 years but not on his right hand, found that after half a century, he did not develop arthritis in either hand.
A later 2011 study came to a similar conclusion: that the risk of developing arthritis is roughly the same, whether a person chooses to crack their knuckles or not.
How to Care for Your Joints Without Cracking Them
Let’s face it, we only get one body to live in. So we should all be caring for our joints as much as possible, as they are essential to maintaining full mobility, enabling us to work, rest and play.
Therefore, I would advise against cracking your knuckles and other joints, like your back, neck, ankles or knees. But if you must, be (very, very) gentle!
Instead, try to:
- Maintain an appropriate body weight to help reduce excess and unwanted pressure on the joints.
- Eat a balanced diet to ensure you get enough calcium to keep your bones healthy and vitamin D to help your body absorb calcium.
- Stay hydrated, as drinking enough water is essential for keeping your joints well lubricated.
- Take regular, low-impact exercise such as walking, cycling and swimming to help keep joints healthy, reduce stiffness and minimise the risk of injury.
- Strength train by building up the muscles surrounding the joints so they can better support you and act as a shock absorber. In an ideal world, according to the NHS’ physical activity guidelines for adults**, we should all be aiming to complete strengthening activities that work all the major muscle groups at least two days a week. A gym instructor or personal fitness trainer can help you with this.
- Stretch every day, to facilitate flexibility and free movement of your joints.
When to See an Osteopath About Joint Pain
If you are experiencing pains in any of your joints, give my North London Osteopathy clinic a call on 020 8815 0979 or request an appointment.
I can assess you thoroughly and provide a personalised treatment plan, including exercises and guidance on preventing injury and making the most of your body.
It may or may not include ‘cracking’ depending on patient preference and requirements!
*https://www.medicalnewstoday.com/articles/259603#why-people-do-it
**https://www.nhs.uk/live-well/exercise/physical-activity-guidelines-for-adults-aged-19-to-64/
