ABSTRACT
The vertebral structures are innervated by the posterior primary rami as well as the sinovertebral nerves.
The spinal nerve is formed by the union of the ventral motor root and the dorsal sensory root. As it exits the intervertebral canal, it subdivides into a large anterior primary ramus and a much smaller posterior primary ramus. C1 and C2 represent exceptions to this rule. The posterior ramus courses around the facet joints, giving rise to branches supplying the joints, ligaments, and all the segmental spinal muscles as well as providing for the cutaneous supply over the back from the vertex to the coccyx. In their anatomic studies, Lazorthes and Gaubert (1956) demonstrated the intimate relationship between these nerves and the zygapophyseal articulations they surround and innervate (Fig. 8.1 to Fig. 8.3).
