Does knuckle cracking cause Osteoarthiritis?
Your sitting down on the bench waiting for a bus or hanging out with some friends when one person begins to crack their knuckles one by one and then their finger joints. You cringe and with each pop and crack you clench you teeth a little more. You think to yourself “Has no one ever told them that cracking their knuckles causes damage to their joints?”. Well your right but the biggest talks is that knuckle cracking causes osteoarthritis of the joints. Knuckle cracking is not an uncommon habit.
Before we talk about what is actually happening to our joints and if we are causing long term damage that can lead to arthritis, let's talk about the anatomy of the joints.
So what is ultimately causing this cracking or popping noise?
When someone is cracking their knuckles they are either over flexing, extending, pulling or pushing side ways. When one does this is increases the space in the joint and decreases the pressure within the joint. This causes the gases that are dissolved, as bubbles, in the joint fluid to burst and break into tiny bubbles and this is what makes the cracking sound.
The tiny gas bubbles take approximately at least 15 minutes to regroup at which point the joint can be cracked once again.
So what does this mean for the joint health itself?
When the joint is over flexed, extended, pulled forcefully or pushed side ways it causes the joint to reaches its maximum distraction (up to 3 times its resting joint space distance). Once the joint is “cracked” it is left with a greater range of motion. Usually when a joint has more range of motion that normal it is placed at a higher risk for injury. The joint is supported by ligaments much like any other joint including the ankle, which is commonly “rolled over” causing an over stretch of the ligaments supporting the joint. Because ligaments have no blood supply and/or vessels to transport new nutrients and 'building blocks' like protein to rebuild and repair damage. So when a ligament is stretched to its limits repeatedly damage can occur and can take a very long time to heal.
Does repeatedly cracking your knuckles cause Osteoarthritis?
Although there has been much speculation that knuckle cracking are associated the studies prove otherwise. Repeated knuckle cracking does not directly cause damage to the joint surfaces it can cause strenuous stress to the ligaments which stabilize the joint.
So think twice before cracking your knuckles because the joint whatever the outcome is taking a tremendous beating in either situation long-term.
References:
Knuckle Cracking and Hand Osteoarthritis, Kevin deWeber, MD, The Journal of the American Board of Family Medicine, March-April 2011 vol. 24 no. 2 pg. 169-174
Effects of habitual knuckle cracking on the hand function, Jorge Castellanos, David Axelrod, Annals of the Rheumatic Disease 1990; 49 pg. 308-309