Dorsal rami of spinal nerves

After the spinal nerves leave the intervertebral foramina, they divide into ventral and dorsal rami. Both rami contain mixed fibers that provide motor and sensory innervation. The dorsal rami are typically smaller than their ventral counterparts. They are responsible for innervation of the deep back muscles, suboccipital muscles, and the skin of the head, neck, and dorsal aspects of the trunk.