Posterior protrusion, also known as thoracolumbar kyphosis, or bilateral scaphoid protrusion, is also called high and low shoulder. The most common clinical cause is scoliosis, mostly in adolescents, also known as adolescent idiopathic scoliosis, which is mainly concentrated in adolescents between 14 and 18 years of age. The main cause is compensatory scoliosis, or structural scoliosis of the spine, due to prolonged improper posture or unbalanced muscle development. In this case, it is recommended to actively improve the cervical, lumbar, and thoracic spine positive and lateral X-rays, or full-length spine X-rays, to understand the angle of scoliosis or kyphosis. If the degree of scoliosis is relatively low, the angle of scoliosis is less than 20 degrees, the purpose of correction can be achieved by correcting the sitting posture, together with the functional exercise of the limbs. If the angle of scoliosis or kyphosis is greater than 20 degrees, a thoracolumbosacral spine brace is required for correction.