What's Cracking?

By Nika Madyoon

Crack. Pop. Click. Whether it’s backs, necks, fingers or wrists, sounds of joints being cracked can be heard in nearly every classroom and hallway. While some students just can’t get enough tension relief in their joints, others are put off by the sound of their classmates’ spines snapping, crackling and popping.

Meghan Hartman ’12, a cellist and member of the pit orchestra, frequently cracks her back and fingers. Spending hours seated in the pit and playing music leaves her in need of a good back-cracking, she said. Hartman also cracks her fingers before beginning a piece.

“It relaxes them and makes me feel like I can conquer passages that require a lot of coordination,” she said. “It helps me loosen myself up and get mentally prepared to dive in.”

The characteristic cracking noise is the result of the stretching of the synovial capsule, said Dimitrios Pappas, a Rheumatology Fellow at Johns Hopkins University spcializing in the treament of joints and tissues. In an interview on the university’s “Arthritis Center” website, Pappas explained that this capsule, which surrounds joints in the body, is stretched when one attempts to crack his or her joints. It contains synovial fluid, Pappas said, and the gas inside this fluid fills the vacuum produced when the capsule is stretched. This gas produces a bubble which, when it bursts, causes the familiar sound.

Pappas attributed the amount of layover time in between each possible joint-cracking to the time required for the gases to be re-dissolved into the synovial fluid. While it is generally thought that cracking one’s joints, particularly in the hand, leads to arthritis, Pappas said that no concrete evidence of this phenomenon has been produced. What it can cause, he said, is injury to the ligaments or tendons surrounding the joint. Studies have also shown that those who frequently crack their knuckles have a weaker grip later in life than those who do not pop their joints.

Hartman doesn’t like hearing her peers engage in the same practice in the classroom. She is particularly bothered by the sound produced when students crack their necks, she said.

“It distracts me from the lesson because the sound is incredibly unappealing,” she said. “It looks like they are trying to rip their heads off. It’s like, ‘You’re not Marie Antoinette, stop it.’”

Ali Bloomgarden ’13 also regularly cracks her joints, particularly those in her back and shoulders. In her case, this behavior is less intentional and more natural. She attributes the phenomenon to her past as a competitive gymnast.

“Ever since then, my shoulders always crack when I roll them,” Bloomgarden said. “It has never failed.”

Bloomgarden said she feels relief just after cracking her joints. She has noticed that a certain sensation of “tightness” in her spine is alleviated when she stretches her back and produces the “crackle” sound. Despite her own tendency to crack her joints, she remains somewhat bothered by the noise when it is produced by those around her.

“It sounds like their backs are going to shatter in front of me,” she said.

While cracking knuckles may not have dire consequences, there are more serious risks associated with cracking joints in other areas of the body, such as the neck.

Wade Smith, M.D., Ph.D., a neurologist and the director of the neurovascular service at the University of California, San Francisco, said that there is a link between neck cracking and the heightened possibility of stroke.

When chiropractors crack a patient’s neck, the process is referred to as spinal manipulative therapy.

Smith, who acknowledges that the risk of having a stroke as a result of this practice is low, is quoted on WebMD as saying, “The consequences of a stroke can be enormous. People should be aware that spinal manipulation increases risk of stroke.”

Alán Sneider ’12, now a habitual knuckle-cracker, spent a great deal of last year popping the joints in his neck.

“I used to do it a lot, but I realized that it could be harmful and decided to stop,” Sneider said.

You must be logged in to post a comment Login