The Spinalis Thoracis is a muscle located in the back, part of the larger group known as the erector spinae. It runs along the spine, connecting the upper and lower regions of the thoracic vertebrae. This muscle plays a crucial role in maintaining posture and supporting the spine during movement. As a component of the spinalis muscle group, the Spinalis Thoracis works alongside the longissimus and iliocostalis muscles. Together, they help extend and rotate the vertebral column, allowing for a range of motions such as bending and twisting. Proper function of this muscle is essential for overall back health.