In chiropractic, we term spinal manipulation as a ‘chiropractic adjustment'. It is a high velocity, low amplitude thrust delivered to a subluxated or fixated joint. The purpose of the adjustment is to restore movement to joints that show aberrant or dysfunctional motion. Often, a ‘click’ or ‘crack’ sound is heard when an adjustment is performed. This is known as a cavitation.

The sound, although often considered to be scary, is not painful and occurs when the pressure from the tissue fluids and joint fluid change. There are some techniques that are used (such as Activator Method) to correct joint movement without creating a ‘click’ or ‘crack’. It is not dangerous to have spinal manipulation done when performed by a properly trained chiropractor.