What’s Popping? Chiropractic Cavitation

Chiropractic cavitation refers to the "popping" or "cracking" sound that sometimes occurs during adjustments, usually when manipulation techniques are applied to the spine and other joints. The sound is often accompanied by a feeling of relief.

The sound of cavitation is produced when nitrogen gas bubbles in the synovial fluid, a lubricating substance found in the joints, are rapidly released. During a chiropractic manipulation, the pressure within the joint space changes; this causes the release of gas bubbles. This sudden release creates a popping sound, similar to the sound of opening a can of soda.

Cavitation itself is a harmless, natural process. It is not an indication of the effectiveness of the adjustment, but simply a byproduct of movement and manipulation of the joint. Some people find the cracking sound reassuring, as it may signal that the adjustment has successfully mobilized the joint which could lead to reduced pain or increased range of motion.

When explaining cavitation to a child who may be unsure of the sound, caves make a good analogy. Joint spaces are like little caves filled with water and bubbles. When a chiropractor adjusts someone, they move the joints and the water in the cave may need more room.  The bubbles pop, that is the sound you hear, and make more room for the water. Then everything feels better because it has the space needed and the bubbles are free.

As a note, not all chiropractic adjustments result may in cavitation, and an absence of the sound does not mean the adjustment was ineffective. Chiropractors use a variety of techniques, some of which may not produce cavitation, but can still be beneficial in addressing musculoskeletal issues.