Your spine gives your body support and allows you to move and bend freely. It is made up of small bones called vertebrae that are stacked up on top of each other and separated by soft discs. The vertebrae normally form a straight line from your head to your tailbone with a slight forward curve at the top and backward curve at the bottom of the spine. However, sometimes the spine will rotate and twist and develop an abnormal sideways curve. This is called scoliosis.