Juvenile scoliosis is a condition (rather than a disease or diagnosis) of abnormal curvature of the spine in children 3 to 9 years of age. While scoliosis can be caused by congenital, developmental, or degenerative problems, most cases actually have no known cause (idiopathic scoliosis).
Scoliosis usually develops in the thoracic spine (upper back) or the thoracolumbar area of the spine, which is between the thoracic spine and lumbar spine (lower back).
It may also occur just in the lower back. The curvature of the spine from scoliosis may develop as a single sideways curve (shaped like the letter C) or as two sideways curves (shaped like the letter S).