Typical spinal nerves are found between T1 and T12, and are restricted by the ribs following a pattern of dermatome and muscle distributions for the trunk. Each somite produces a nerve pattern that relates the cord to the respective body somites along the dorsal and ventral root plan. These nerves distribute somatic motor and somatic sensory to the body.

• Typical spinal nerves are found between T1 and T12, and are restricted by the ribs following a pattern of dermatome and muscle distributions for the trunk. Each somite produces a nerve pattern that relates the cord to the respective body somites along the dorsal and ventral root plan. These nerves distribute somatic motor and somatic sensory to the body.

• Visceral efferents target sympathetic (paravertebral) ganglia on each nerve segment. Afferents of the viscera are from the dorsal root ganglion cells and enter the cord from T1 to L2 to target visceral sensory related secondary cells in the cord. These axons connect to serve in reflex connections with sympathetic efferents. Spinal nerves, T2 through T12, are typical in that they serve the vertebral column and the body wall as direct segmental dermatomes.