Baby joint ringing is mostly seen in two joints, respectively, the hip and knee, the reasons are as follows: 1, hip popping: hip popping means that there may be congenital developmental problems of the hip joint, congenital hip dislocation is more common, parents bathing and dressing their children, or children do gymnastics when the hip joint has a ringing sound, suggesting that the baby hip dislocation, parents should pay attention to, should be sent to the hospital in a timely manner for specialist medical examination. For babies within six months, hip ultrasound can be done to clarify whether there is any developmental problem in the hip joint, and for babies between six months and one and a half years old, X-rays can be taken to see whether there is hip dislocation. Babies with hip dislocation within six months need to wear a special hip abduction brace. Babies with hip dislocation between six months and one and a half years old need to be reset under anesthesia and treated with prolonged hip plaster fixation; 2. Knee popping: The most common and most important problem of knee popping is congenital knee meniscus Developmental abnormalities, medically known as congenital discoid meniscus, require MRI to clarify whether there is a congenital developmental malformation of the meniscus. Children with congenital discoid meniscus can have long-term, chronic pain in the knee joint, and need arthroscopic surgery if they cannot get better.