What is in Your Back?

Your back is an intricate network of muscles, ligaments, discs and nerves. It is a delicate system with an enormous responsibility. Your back carries most of your body's weight and includes your spinal column, the main pathway of your nervous system.

Back

The Parts of Your Back

Your spine is the primary component of your back. It supports your head and trunk, gives flexibility to your body and protects your spinal cord. Small bones called vertebrae form your spine. The five types of vertebrae have unique forms suited to their locations and functions.

There are seven cervical vertebrae supporting your skull and neck. They tend to be smaller and more flexible than the other vertebrae. Your chest cavity is formed by 24 ribs extending from the twelve thoracic vertebrae. The five lumbar vertebrae are the largest and carry most of your body weight.

Below your lumbar vertebrae is the sacrum, a single bone consisting of five fused vertebrae. At the base of your spine is the coccyx, or tailbone, which is also formed by fused vertebrae.

In between your vertebrae are shock absorbers called discs. Discs have a strong outer casing with a pliable jelly-like substance inside. The top and bottom of the disc is attached firmly to the vertebrae. Although you often hear of a "slipped disc", discs cannot slip out of place. When a disc is damaged, the jelly-like substance may protrude from between your vertebrae, creating the impression that a disc has moved.

Your spinal cord, with your brain, forms your central nervous system. It is approximately 18 inches long and one-half inch thick. Your vertebrae form a canal through which it runs. About 31 pairs of nerves branch out from your spinal cord and travel throughout your body. These nerves carry commands to your organs and muscles and relay messages relating to touch, temperature and pain.

Approximately 400 muscles work together to stabilize your spine, maintain proper posture and allow movement. More than 1,000 tendons connect these muscles to your bones.

Ligaments are bands of tissue between your bones that maintain the spine's alignment. They prevent damage due to excessive movement.

Keep Your Back in Balance

Each of the muscles, nerves, and bones in your back has a unique role in the proper operation of your back. Your role is to practice proper posture and good body mechanics to maintain the healthy balance of your back.

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