The effects of knuckle cracking has been studied in “habitual knuckle crackers” and has been studied by bioengineers. The sound of knuckle cracking comes from a rapid release of gas bubbles within the joint. When the bubbles suddenly collapse, a large sound is the result. In a clinical study of over 300 patients who were “habitual knuckle crackers” for at least thirty years, xrays showed no increase in the incidence of arthritis. However, the knuckle crackers were more likely to have mild hand swelling and lower grip strength !

So should you or shouldn’t you crack? I recommend that you listen to your mom.