The thoracic spine is the middle section of the spine, consisting of twelve vertebrae labeled T1 to T12. It connects the cervical spine in the neck to the lumbar spine in the lower back. The thoracic spine plays a crucial role in supporting the rib cage and protecting vital organs in the chest, such as the heart and lungs. Each thoracic vertebra has a pair of ribs attached, allowing for flexibility and movement while providing stability. The thoracic spine also helps maintain an upright posture and is involved in various movements, including twisting and bending of the upper body.