Back cracking does not mean a vertebra is moving back into place, experts say

Cracking the back after long periods of sitting may feel relieving, but the sound does not indicate a vertebra shifting out of position and snapping back. The facet joints between vertebrae contain synovial fluid, and movement lowers pressure enough to form a gas bubble. This process, known as cavitation, is the leading explanation for the popping sound. In a survey of 100 people, 49 percent believed the sound proved a bone had been realigned, while only 9 percent linked it to gas inside the joint. In a separate question, 40 percent said the cracking signaled that a treatment had worked. A 2022 systematic review of 303 adults found that noisy and silent manipulations produced similar pain relief, and that repeated cracking did not increase the sensation of relief. Specialists say that mild, painless joint sounds are not by themselves a warning sign, but forcing the back to crack with hard, repeated pressure is not recommended. Severe or persistent pain, numbness, muscle weakness, fever, or changes in bowel or bladder control warrant medical evaluation, they added.