The spinal cord is organized into five segmental divisions (cervical, thoracic, lumbar, sacral, coccygeal), each further subdivided into discrete levels, and each level gives rise to a corresponding pair of spinal nerves, totaling 31 pairs. The cervical segment is an exception to the general correspondence between segment count and vertebral count, having one more spinal nerve level (eight) than cervical vertebrae (seven), while the thoracic, lumbar, and sacral segments each have a spinal nerve count equal to their respective vertebral count. This is foundational content in neuroanatomy concerning the segmental organization of the central and peripheral nervous system.
The spinal cord is organized into five segmental divisions (cervical, thoracic, lumbar, sacral, coccygeal), each further subdivided into discrete levels, and each level gives rise to a corresponding …