In order to understand why Upper Back Pain occurs, it’s helpful to know the basic anatomy of the spine. The spine is made up of 33 individual bones called vertebrae. The vertebra are numbered and divided into four regions. 12 thoracic vertebra are joined by ribs to form your rib cage. Facet joints are located between each pair of vertebrae. They guide and limit the movement of the spine, providing stability and bearing a share of the load on the spine.