When you are bored, do you unknowingly crack your knuckles?

The answer is yes, and this causes the joints of the fingers to make sounds.

But have you ever wondered: Why is there a sound when you move your finger joints? Does doing it too often cause arthritis or thick fingers?

What is the clicking sound when you crack your knuckles? First of all, let's understand the structure of our finger joints. The finger joint is a cavity surrounded by cartilage, ligaments, synovium, etc. There is a small amount of transparent viscous fluid in the joint cavity, which is called synovial fluid. When the joint is moving, in addition to the movement of the bones, the surrounding ligaments also protects the stability of the joint at all times. The synovial fluid in the joint cavity is like "lubricating oil" to make the joint move more freely. As for finger- snapping sounds, the bursting of this bubble is by far the most common explanation. When you snap your fingers, negative pressure will be generated in the joint cavity, and the gas in the synovial fluid exists in the form of air bubbles. When the air bubbles are squeezed and burst, they will make a "click" sound. ^[1]