What's that sound? It's the symphony of chiropractcic.

Have you ever wondered what is actually “cracking” during a chiropractic manipulation? The audible “cracking” or “popping” sound that you hear during a manipulation is not that different from the sound you hear when you crack your knuckles. This sound actually has an official name, cavitation.  And this cavitation is not your bones breaking, or ligaments snapping, but rather the quick release of gas that can occur within a joint.  Many of our joints are what are classified as synovial joints- meaning there is a capsule that exists within the joint along with synovial fluid. Synovial fluid is the natural lubrication that occurs within a joint allowing it to move pain-free. 

Restrictions in joint mobility, often due to misalignments or adhesions, can contribute to the build-up of gas. When a joint is not moving through its full range of motion, the synovial fluid becomes stagnant, allowing gas to accumulate over time. Thus, the more restricted an area of your spine is, the more pressure that develops there. This pressure can be felt as loss of ROM, pain, tension, etc.

During a chiropractic adjustment, or manipulation, your joints get stretched near their end range.  This can allow for a myriad of things to ensue like relaxation of the surrounding musculature, but more excitingly, the cavitation.  When a joint capsule is stretched it creates a negative pressure within the capsule leading to the formation and collapse of gas bubbles. These gas bubbles are mainly nitrogen and materialize as the gas is pulled out of solution by the negative pressure that happens as a result of the capsule stretching.
​
So what does this mean- is my adjustment not working if there’s no sound? Cavitations can vary between people, and can even vary depending on the body part in the same individual. Oftentimes cavitations occur without the added force of a chiropractic adjustment, like when you’re moving after sitting down for a long time.  The effectiveness of a chiropractic manipulation is not determined by how loud a cavitation is, contrary to popular belief. There are no known downsides or risks associated with the frequency of a cavitation within a particular joint, or even how loud a cavitation is at this time. The “cracking” or “popping” sound is just a bonus!