Developmental Dysplasia of the Hip (DDH), formerly known as Congenital Dislocation of the Hip (CDH), is a general term for a group of pathologies characterized by spatial and temporal instability of the hip joint during development, including hip dislocation, subluxation, and acetabular dysplasia. DDH can cause abnormal gait, abnormal development of adjacent joints, and secondary deformities of the spine, leading to lower back pain and pain due to degenerative hip joint degeneration in adulthood. Because the disease is closely related to the developmental process of the hip joint, the presentation and corresponding treatment varies between age groups. The goal of DDH treatment is to obtain a stable concentric reposition and avoid ischemic necrosis (AVN) of the femoral head. Early diagnosis and treatment are the keys to improve the outcome.