The etiologic classification of scoliosis in children and adolescents aged 10 to 18 years includes syndromic, congenital, and neuromuscular scoliosis. If a specific etiology of scoliosis is not identified, it is classified as adolescent idiopathic scoliosis (AIS). Adolescent idiopathic scoliosis is the most common type of spinal deformity in this group. Scoliosis is defined as a spinal deformity in which the coronal plane exceeds 10°. The normal spine is straight in the coronal plane, whereas in the sagittal plane the average thoracic kyphosis is about 30° and the average lumbar anterior kyphosis is about 55°. Adolescent scoliosis is more common in females than males, and for adolescents with scoliosis of more than 10°, the incidence is 1% to 3%. For adolescent scoliosis with more than 40° of scoliosis, the incidence is approximately 0.1%. In general, treatment of adolescent idiopathic scoliosis includes follow-up observation, brace therapy, or surgery. In patients with immature skeletal development, follow-up observation should be considered for scoliosis less than 25°, bracing should be used for scoliosis between 25° and 40°-45°, and surgery should be considered for scoliosis greater than 45°-50°. Usually, patients with mature bones are not treated with bracing. In skeletally mature patients, the growth of scoliosis can be observed straight up to 40°, and surgery is considered when it is greater than 45°~50°.