Why do the joints of the body always ring?

1) gas escape: scientists believe that there is a synovial fluid between our joints.

Liquid is used to lubricate joints. This synovial fluid contains some gases, such as oxygen, nitrogen and carbon dioxide.

Carbon. These gases form bubbles in the synovial fluid. When we stretch our joints, the gas in the synovial fluid flows quickly.

If you drop it, it will cause hiccups, because the bubble is broken.

2) Joint displacement: When we move joints, tendons and ligaments will be displaced. When tendons and ligaments return to their original positions,

You sometimes hear burps. This situation is mostly knee joint and ankle joint.

3) Joint contact surface caused by arthritis: Arthritis will destroy cartilage tissue between joints and cause joint contact.

The face is no longer smooth. In this case, joint friction will produce noise.