Nerve · Head

Third occipital nerve

Nervus occipitalis tertius

The medial branch of the dorsal ramus of the third cervical nerve, and the smallest of the three occipital nerves. It pierces semispinalis capitis and then trapezius to supply a narrow strip of skin over the lower back of the head, immediately alongside the wider territory of the greater occipital nerve. Its more consequential job is out of sight: on the way it supplies the facet joint between the second and third cervical vertebrae, the highest joint in the neck with a conventional facet. One small nerve therefore serves both a patch of scalp and a joint of the upper neck, which is unusual company for a cutaneous branch to keep.