Understanding the Chiropractic “Crack”: What’s That Sound?

Many patients are curious—or even a little nervous—about the “crack” heard during a chiropractic adjustment. This sound is known as joint cavitation, and it’s completely normal.

The sound is caused by the rapid separation of joint surfaces, which releases gas (mostly nitrogen and carbon dioxide) from the synovial fluid inside the joint. It’s similar to the noise when you crack your knuckles.

Importantly, the sound is not necessary for the adjustment to be effective, and not all techniques produce cavitation. At State College Family Chiropractic Center, we use a variety of adjustment methods—some with audible release, and others without—to meet your comfort level and therapeutic needs.