Spinal Column Anatomy: The Basics

When a spinal cord injury occurs, sensation and movement may be interrupted, resulting in a temporary or permanent loss of function, paralysis and loss of sensation. Here are some basic anatomy facts:

  • The brain is surrounded by the skull.
  • The spinal cord is surrounded by rings of bone called vertebrae.
  • Both are covered by a protective membrane.
  • Together, the vertebrae and the membrane make up the spinal column, or backbone.
  • The backbone, which protects the spinal cord, starts at the base of the skull and ends just above the hips.
  • The spinal cord is about 18 inches long. It extends from the base of the brain, down the middle of the back, to just below the last rib in the waist area.
  • The main job of the spinal cord is to be the communication system between the brain and the body by carrying messages that allow people to move and feel sensation.
  • Spinal nerve cells, called neurons, carry messages to and from the spinal cord, via spinal nerves.
  • Messages carried by the spinal nerves leave the spinal cord through openings in the vertebrae.
  • Spinal nerve roots branch off the spinal cord in pairs, one going to each side of the body.
  • Every nerve has a special job for movement and feeling. They tell the muscles in the arms, hands, fingers, legs, toes, chest and other parts of the body how and when to move. They also carry messages back to the brain about sensations, such as pain, temperature and touch.