The Spinalis Capitis is a muscle located in the back of the neck, part of the larger group known as the erector spinae. It plays a role in extending and rotating the head. This muscle is situated near the upper part of the spine and connects the cervical vertebrae to the skull. As a component of the spinalis muscle group, the Spinalis Capitis works alongside other muscles like the longissimus and iliocostalis. Together, these muscles help maintain posture and support movements of the head and neck, contributing to overall spinal stability.