Although a lot of people love cracking their knuckles, the habit is poorly understood. Many likewise believe that knuckle-cracking may cause a number of health problems. Some people, for instance, think that the habit can lead to arthritis.

Experts, however, say that the painless cracking of the joint should not be harmful. Cracking the knuckles does not also cause arthritis as many have come to believe.

A number of studies have looked into the prevalence of individuals who love knuckle-cracking among groups of patients suffering from osteoarthritis, but researchers have not found evidence that poppers and finger pullers have increased odds of suffering from arthritis over their counterparts who do not crack their knuckles.

A habitual cracker also conducted a study on himself. After about six decades of habitually cracking the joints on his left hand, he found that there was no increased presence of arthritis in his left hand when he compared this to his right hand.

"Finger cracking is so common you would expect to see a lot of causal reports if it was harmful," said Pedro Beredjiklian, chief of hand and wrist surgery at Philadelphia's Rothman Institute. "But you don't. So I think it's unlikely cracking joints in hands leads to arthritis."

Intentional and repetitive cracking of the knuckles could, however, cause problems when it already produces pain. Knuckle cracking may also cause instability in the joint as well as loss of hand function and grip strength. The habit may also be socially annoying.

Some, however, can't take off the habit because cracking the knuckles can make you feel good as the practice stretches the joints as well as stimulates the nerve endings there.

Experts previously believed that the chilling noise behind that cracking of the joints has something to do with the collapse of air bubbles in the synovial fluid, which lubricates the joints. Findings of a new study published in the journal PLOS ONE on April 15, however, suggest that the sound can be attributed to the formation of a gas-filled cavity when the bones in the joints stretch apart.

"Bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon," study researcher Gregory Kawchuk, from the University of Alberta, and colleagues wrote. "Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse."

Photo: Jaysin Trevino | Flickr