In pediatric orthopedic clinics, parents often ask, “My child was just born and the doctor said that he has hip dysplasia, I am very nervous. What are the future consequences of hip dysplasia? How to detect and treat it early? Developmental dysplasia of the hip (DDH) is a collective term that describes congenital or developmental anatomical abnormalities of the hip joint in infancy and childhood. These abnormalities range from mild defects, such as shallow acetabulum, to severe defects, such as malformed dislocation. Developmental hip dysplasia is one of the more common osteoarthritic deformities in children , with about 0.5-1% of hip instability at birth, but the incidence of typical developmental hip dysplasia in infants is about 0.1%. It is more common in boys than girls, unilateral than bilateral, and left than right. Mild hip dysplasia can lead to a high incidence of degenerative arthritis in adulthood, so it should be taken seriously. What are the signs of developmental hip dysplasia in newborns? Parents of new parents are immersed in joy, if they find that the baby’s perineum is widened, both hip joints are restricted in abduction, and the hip folds or thigh skin lines are obviously asymmetrical, they should be more alert. The possibility of “hip dislocation” is even greater. Generally speaking, after careful examination by pediatric orthopedic surgeons and supplemented by relevant auxiliary examinations (hip ultrasound at less than 6 months of age, X-rays at more than 6 months of age), most of the diagnosis can be confirmed, if parents are careless, wait until the child starts to walk (generally later than children of the same age), and if the dislocation is bilateral, it will appear “duck walk”, unilateral dislocation is swaying limp, then it should be treated as early as possible to avoid the occurrence of permanent defects of the body, affecting the child’s mental health, marriage and career development, leaving lifelong regrets. The early diagnosis of hip dysplasia is crucial to achieve good results. If the hip joint is subluxed or fully subluxed, it is impossible for the hip joint to develop normally, so the treatment effect has a great relationship with age. Treatment of developmental hip dysplasia can be challenging. Delayed diagnosis or problems in treatment often lead to residual anatomical defects and secondary degenerative arthritis. Generally speaking, children between birth and 6 months of age are treated with a Pavlik dressing; children between 6 and 18 months of age have a high cure rate with “closed repositioning + frog cast fixation”; children over 18 months of age have increased bony deformity of the femoral head and acetabulum with age and significant contracture of the adductor muscles, as well as decreased plasticity of the acetabulum and acetabular cartilage. The plasticity of the femoral head cartilage decreases, then surgical treatment is the main treatment, and the program of surgery varies from person to person and from disease to disease. It is difficult to achieve normal function despite regular treatment, and some data show that after regular treatment of children over 1.5 years of age, more serious degenerative osteoarthropathy has occurred in about 50% of patients at 45 weeks of age, requiring replacement of the artificial joint. Birth to 6 months of age is the best period of non-surgical treatment, such as early diagnosis and early treatment, clinical results are satisfactory, if delayed treatment, will eventually lead to irreversible painful osteoarthritis and varying degrees of disability, in view of China’s national conditions, the higher cost of surgery for the majority of families (especially rural families), are a great burden, the impact on the child is great, and the effect Ultrasound has an unparalleled role in the diagnosis of children with early hip dysplasia.