Chiropractors are often asked what’s the ‘popping’ or ‘cracking’ sound that’s produced with a chiropractic adjustment. The answer is gas bubbles popping within the joint.
A joint is the connection of two bones in the body. The joint is held together by a capsule of soft tissue and within this capsule is fluid. There are small gas bubbles sitting in the joint capsule fluid.
The chiropractic adjustment creates motion at the joint which pops these gas bubbles. The popping of the gas bubbles is just a side effect of the adjustment, it is not itself therapeutic. It is the restoration of movement in the stiff joint that is therapeutic. The adjustment targets the specific joint that is stiff and painful to remove that stiffness and pain. This is why Chiropractic adjustments are superior to self-manipulation (cracking your own neck or back).
So the cracking sound heard with a chiropractic adjustment is just popping bubbles. The real benefit of chiropractic adjustments comes from the removal of stiffness and pain.