Most of the joints in the body are physiologically rattling, which occurs when the body is bearing weight or flexing or extending the joints. When each joint is moving, the joint cavity itself is a closed cavity, which can be diffused by air entering when the joint is flexed, and the gas is vibrated and causes rattling. It can also be due to the joint activity, tendons, muscles, cartilage, ligaments, bone surface of the friction of each other appear popping. Most of the pathological ringing is seen in the middle-aged and elderly people with high physical exercise intensity. With the degeneration of joint capsule, ligament relaxation, tendon hyperplasia, calcification, or narrowing due to degeneration of tendon sheath, and calcification due to poor nutritional status of articular cartilage, multiple ringing of joints often occurs during physical activities. Most of the other joint pathological ringing originates from a single joint ringing and does not occur in multiple joints, such as ringing hip and knee, which are related to muscle degeneration, calcification, and meniscal lesions.