Bones make a rattling sound, usually when the joints, cervical spine, and lumbar spine are moving. This is mostly due to the popping sound that occurs in the joint capsule, the small joint capsule of the cervical spine and the lumbar spine. This popping sound occurs when gas flows in the joint cavity, creating negative pressure. Sometimes the bursa fluid is low and the bones rub against each other during movement, which also causes a popping sound. The reason for the reduction of bursal fluid in the joint bursa is usually degeneration of the joint, because the joint bursa is in a sterile inflammatory environment for a long time and the joint bursa is pathologically changed, so that the secretion of bursal fluid is reduced and is not enough to lubricate the joint. The joint loses the lubrication of the bursa fluid, and direct contact during movement results in a sound. It is not usually associated with pain or limited function. This is a condition that we can live with normally and does not require deliberate attention or concern. However, if, in addition to the sound, the joint is red, swollen, painful, and limited in movement, then there may be a problem with the joint. In this case, we should pay attention to it and go to the hospital in time to avoid delaying the condition.