What actually causes the cracking sound?

The sound comes from a process called cavitation, happening inside the fluid-filled capsule that surrounds your joints (synovial fluid). When a joint is gently stretched or moved beyond its usual range, as happens during an adjustment, the pressure inside the joint capsule drops rapidly. This causes a small gas cavity to form almost instantly in the fluid — and it’s this rapid cavity formation, not a bone moving, that produces the audible “crack” or “pop.”

Does the sound mean a bone was “put back into place”?

No. This is one of the most common misconceptions about chiropractic care, and survey research backs that up — in one study, fewer than 1 in 10 people correctly identified the cause of the cracking sound as gas-related, while around half believed it meant a vertebra had been “repositioned.”

An adjustment works by applying a controlled, targeted force to a joint to improve its movement and reduce pain — the cavitation sound is simply a by-product of that movement, similar to the sound when you crack your knuckles. It isn’t evidence that anything was structurally relocated.

Does a louder or more frequent “crack” mean a better adjustment?

No, and this is an important point for setting realistic expectations. The presence, loudness, or number of cracking sounds during an adjustment doesn’t correlate with how effective the treatment is. Some adjustments produce an audible release; others don’t, and both can still achieve the intended improvement in joint movement.

Dr. Brian assesses the success of an adjustment by changes in your movement, muscle tension, and reported symptoms — not by whether (or how loudly) a joint cracked.

Is it safe for a joint to “crack” repeatedly?

Occasional joint cracking, whether during a chiropractic adjustment or everyday movements like cracking your knuckles, is considered a normal physiological event and is not associated with joint damage in the research literature. After a joint cavitates, there’s typically a refractory period of about 15-20 minutes before that same joint can “crack” again, because the gas needs to redissolve into the fluid.

What if my adjustment doesn’t produce any sound?

That’s completely normal and nothing to be concerned about. Not every adjustment technique relies on or produces an audible release — many techniques, including instrument-assisted and soft-tissue approaches, are designed to improve joint movement without producing a “crack.” The absence of sound doesn’t mean the technique was less effective.