The Spinal Cord
The spinal cord exits the brain at the brain stem and travels down the middle of the skeletal column down to the 1st and 2nd vertebrae.
At this point hair-like nerves form a tail and spread through the lumbar and sacral region. This is called the Cauda equina (horse tail).
31 spinal nerves leave the vertebral spaces, named according to the section they leave the spinal column:
Cervical = 8 pairs
Thoracic =12 pairs
Lumbar = 5 pairs
Sacral = 5 pairs
Coccygea = 1 pair
Spinal nerves contain motor fibres.
Nerves convey messages from the cord to muscles.
Sensory fibres carry information into the cord.
KEY TO NERVES
BLUE = Cervical
GREEN = Thoracic
YELLOW = Lumbar
RED = Sacral / coccygeal