Why does's neck ring as soon as it turns? With the growth of age, fatigue and other factors, the human articular cartilage inside the loss of glucosamine, chondroitin and so on, cartilage gradually shrink, (which is why people get shorter in age) our body joints gradually become rigid. At the same time, the joint fluid is gradually reduced, and the joint is easy to wear and tear in the state of lack of lubrication. For example, many people have ridden a bicycle and know how it would feel if there was a shortage of oil in the axle? Must be riding hard, must feel the ball inside the rotation is not flexible and there is a sound, a bit similar to our neck sound. It's just, since