Joint Popping

Is it normal for your joints to pop or crack? And what causes the noise? These are frequently asked questions and not too difficult to answer. Joints can pop for several reasons and most of the time it is absolutely nothing to be concerned about. Occasionally it could mean that something might be a bit out of sync in your body. Here is how to distinguish the normal pop from the abnormal pop.

For a long time, the exact science behind the cracking of joints was a mystery but due to recent studies we now have a better understanding. Most joints have a capsule that surrounds it to keep the joint fluids inside. As the joints surfaces are pulled apart, they create space for a tiny bubble of dissolved gases to form. The popping noise is caused by the rapid expansion and then collapse of the bubble. This is called cavitation and is the most common cause of popping in joints such as your knuckles, toes and spine.

Previously, it was believed that frequently popping your joints would lead to arthritis but there has been further research on this topic. Dr Donald Unger researched his own hands by popping the knuckles on his left hand twice a day for 50 years, but not the knuckles on his right hand. He concluded that there was no difference between the two hands and that popping your joints is not linked to arthritis. Furthermore, a study was conducted by The Uniformed Services University of the Health Sciences that examined a group of 215 people, 20% of which popped their knuckles regularly. They found a no major difference between the groups with 18.1 % of the knuckle poppers experiencing arthritis compared to 21.5% of the group that did not pop their knuckles. However, popping your joints may not be without consequence. Another study showed that although it is not linked to arthritis, it can still cause a higher rate of inflammation inside the joint and a weaker grip.

The relief we experience from popping our joints are due to the stimulation of the surrounding nerve endings, causing the nearby muscles to relax and therefore allow the joint to feel freer and more mobile. There is no exercise to prevent or treat joints that pop and as long as it is not accompanied by pain or swelling, it is a completely normal occurrence although somewhat annoying.

Other joint noises may be due to tight tendons rubbing over the bones, causing a snapping sound. This is common in joints such as the shoulder, hip and ankle. Occasionally this may become painful as the tissues become irritated and inflamed. Ligaments can also make a similar sound as they are pulled tight. Some gentle stretching and strengthening exercises may help reduce this by correcting the biomechanics.

Sometimes joints make other noises such as crunching, this could be indicative of degeneration in the cartilage of the joint and is usually accompanied with other symptoms such as swelling, stiffness and pain. Other noises such as clunking, especially in the knee, could be indicative of damage to the meniscus and would usually be accompanied by instability or even locking of the joint.

In a nutshell, the popping of joints is normal and unless accompanied by other symptoms such as pain, stiffness, swelling or instability.


  1. Does cracking your knuckles cause arthritis? (n.d). Retrieved form
  2. DeWeber, K., Olszewski, M., & Ortolano, R. (2011, March-April). Knuckle cracking and hand osteoarthritis. Journal of the American board of family medicine, 24 2, 169-174. 
  3. Lauridsen, D. J. W. (2007, March 30). A curmudgeonly clarification of “cavitation” and a call to correct all cracking content. The science creative quarterly, University of British Columbia, CA.