The term thoracic nerves refers to the 12 pairs of spinal nerves that originate from thoracic segments (SPCth) in the middle of the spinal cord (SPC) ventral to the cervical nerves and dorsal to the lumbar nerves. They are a principal component of the peripheral nervous system (PNS) ( Kahle-2003 ) and are found in all vertebrate species ( Swanson-2015 ). Final 26 Dec 2024.