The thoracic spine is made up of the middle 12 vertebrae. These vertebrae connect to your ribs and form part of the back wall of the thorax (the ribcage area between the neck and the diaphragm). The thoracic spine's curve is kyphotic, a "C"-shaped curve with the opening of the "C" in the front. This part of the spine has very narrow, thin intervertebral discs. Rib connections and smaller discs in the thoracic spine limit the amount of spinal movement in the mid back compared to the lumbar or cervical parts of the spine. There is also less space inside the spinal canal.