That snap-crackle-pop of the spine is a familiar sound. It can happen during a yoga twist or when you turn to reverse your car out of a driveway. You can induce the cracking yourself by leaning backward over a chair or by getting into a front-facing, Heimlich-like hug with another person. And, of course, a session with a chiropractor or masseuse can elicit an audible ripple.
Just what causes this crackling? Tiny gas bubbles. Along with lubricating synovial fluid, joints contain oxygen, nitrogen and carbon dioxide. When the fluid is put under pressure from twisting or pushing the spine, the gases release, creating a pop. This reaction is normal and harmless, according to Patrick Roth, MD, a neurosurgeon at Hackensack University Medical Center and author of The End of Back Pain. It’s also normal to find yourself getting more “gassy” as you get older, says Roth. “As we age, our joints may become larger, simply from repetitive biomechanical stress,” he explains. Bigger joints, more noise.
Not only is the noise benign, but it can also be satisfying, as many people enjoy the sensation of the ripple. “Cracking your back can feel like a relief because with the release of carbon dioxide gas, the vertebrae move ever so slightly, giving you a looser, freer range of motion for your joints and bones,” says Todd Sinett, DC, a New York–based chiropractor and author of the soon-to-be-released 3 Weeks to a Better Back. There’s also an unproven theory that cracking releases natural painkillers (in the endorphin family), which can be addictive.
However, Sinett cautions that DIY cracking is not always wise. “If your back cracks or releases on its own, during normal movement or in a yoga twist, this is fine, but you don’t want to force it.” Why? Each time you manipulate your joints, you stretch the ligaments surrounding the joints. Stretch them too many times and, like a rubber band, they can lose shape—and the ability to provide the stability joints need for proper alignment. As Sinett explains, this condition—called hypermobility—can cause muscle pulls and spasms as well as lead to misaligned vertebrae and pinched nerves.
When it comes to cracking the neck, there is debate in the medical community regarding risk versus benefit, says Jennifer Kaur R. Sohal, MD, an orthopedic surgeon at St. Vincent Medical Center in Los Angeles. Sohal believes that, in general, for someone who has no neck pain, stiffness, tingling or numbness, cracking is okay. The caveat: “People who have neck problems, especially stiffness, should be evaluated by their primary care doctor, orthopedic surgeon or spine surgeon to screen for [serious conditions such as] a herniated disc or compression of neurologic elements.” Sohal stresses that you should not self-crack or have your neck manipulated by a chiropractor until you have been cleared by a doctor.
As Roth puts it, “The neck is different from the lumbar spine in that it encases the cervical spine, which is a much more sensitive structure than the lumbar.” When you twist and torque this area, you run the risk of a spinal cord injury, which is rare, but dangerous when it occurs. If you’ve been given medical clearance and aren’t suffering from pain, a professional chiropractor may provide relief from slight stiffness with adjustments, according to Roth. “A skilled chiropractor can create a slight reorientation of joints and realign them with pressure or rotation,” says Roth, who adds that this manipulation of the joints can create a snapping sound similar to the release of gas bubbles.
Of course, some of us simply crave the release from adjusting our backs and are doing it out of habit (like knuckle-crackers). While that’s not necessarily harmful, it may be a warning sign. As Sinett puts it, “If you feel a consistent need to pop your own back, it may be because you are uncomfortable and something isn’t right.
Bottom line? If you’re a “crack addict,” it might be wise to go cold turkey—or at least back off a bit.