Whether it’s one or all of your knuckles, you may wonder what causes the cracking sound. Although interesting, “cracking joints” and “popping knuckles” are not fully understood.

Many people crack their knuckles habitually, unconsciously, or sometimes for relief. The sound is caused by the bursting or collapse of gas bubbles in the synovial fluid within the joints.

We have all seen movies where right before the hero starts fighting, he cracks his knuckles and makes it look like the coolest thing in the world! But then our parents told us that you should not ...