The splenius muscle of the head and the splenius muscle of the neck work together so that the neck and the head can extend (tilt backward) and rotate.

The splenius muscle of the head, also known as the splenius capitis, is a broad muscle located at the back of the neck. It is attached to the base of the skull.

The splenius muscle of the neck, also known as the splenius cervicis, is a smaller muscle that is positioned slightly below the splenius capitis.

Damage or injury to either splenius muscle can cause neck pain, headaches, facial pain, or shoulder pain. Oftentimes physical therapy, stretching, ice, or heat can help to alleviate the pain. Oral medications and medications injected into or around the muscle may also help to control the pain associated with the damage.

For treatment of severe pain or prolonged pain, which is often accompanied by nausea or vomiting, radiofrequency thermoneurolysis is sometimes used. This is a procedure where a small probe uses radiofrequency energy to cauterize (burn) a cluster of nerves in order to stop them from sending pain signals.