This is Why You Should Not Crack Your Fingers More Than Once Per Day

Probably, when you were a child, your parents told you all the time to stop cracking your knuckles since you can get arthritis or your hands can start shaking. There is no scientific proof about this, but it is not recommended to stop doing this.
 

 

The joint connects two bones, and between them there is a cartilage which protects the bones. They are connected by a tissue and ligaments, and in the middle there is a joint capsule filled with blue liquid. It contains dissolvable gases and the reason behind its existence is to prevent friction of the cartilage.

There are bubbles created in this liquid and they pop during the cracking of knuckles and fingers. When you do this, you widen the joint capsule and you create bubbles with blue liquid i.e. process of cavitation.  The sound of popping comes from the bubbles.

Although there are no evidence about the negative effect of cracking your knuckles and fingers on your health, you should stop practicing this.