What are the different parts of the back?

The different parts of the back include the following:

  • vertebrae, which are bones stacked like a tower
  • joints that act like hinges in between the vertebrae to allow the spine to twist and bend
  • sacrum, part of the pelvis that supports the spine
  • coccyx, formed by the bottom vertebrae
  • iliac bones in the pelvis support the sacrum through the sacroiliac joints
  • sacroiliac joints support most of the body's weight
  • strong ligaments attached to the sacroiliac joints help keep the pelvis and spine stable

The spine (or backbone) is made up of small bones called vertebrae. The vertebrae are stacked on top of each other to form a column. Between each vertebra is a cushion known as a disk. Each disk has a soft, gelatinous core and a tough, fibrous capsule (outer shell). The vertebrae are held together by ligaments, and muscles are attached to the vertebrae by bands of tissue called tendons. Openings in each vertebra line up to form a long, hollow canal. The spinal cord runs from the base of the brain down through this canal. Nerves from the spinal cord branch out and leave the spine through the spaces between the vertebrae.

The lower part of the back holds most of the weight of the body. Even a minor problem with the bones, muscles, ligaments or tendons in this area can cause pain when a person stands, bends or moves around. Less often, a problem with a disk can pinch or irritate a nerve from the spinal cord, causing pain that runs down the leg, to below the knee. This type of pain is called sciatica.

Your back is made up of an intricate system of bones, nerves, and tissues. The three main ones you want to learn about are the vertebrae and discs, the muscles and the nerves and myelin. All three areas can be sources of pain.

Your spine is comprised of small-stacked bones (the vertebrae) that form a column separated by discs. Think of your spine as a column of doughnuts separated by a nice wedge of havarti cheese: The vertebrae are the doughnut portion and inside the hole travels the spine; the harvarti is the disc. If the havarti is pushed out of place, you have a bulging disc.

Surrounding your spine, there's a large and complex set of muscles that have the job of an anatomical administrative assistant; they're all about providing support. These muscles are broken into three broad categories: Extensors, which are attached to the back of the spine and give you the strength to stand; flexors, which are in the front of the spine and help you bend forward; and obliques, which are attached to the sides and help you win twist contests. Also important in this complex are the abdominal muscles - actually the most important front muscles of the lower back.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.