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Overview of Spinal Cord Disorders


The Manual's Editorial Staff

Reviewed/Revised Sep 2023
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What is your spine?

Your spine is your backbone. It's actually a long line of 24 bones called vertebrae plus your tailbone (sacrum). The vertebrae start below your skull and go all the way down to your pelvis. The vertebrae bear most of your body's weight.

There are small discs of cartilage between each vertebra. The cartilage is a flexible, rubbery material that acts like a cushion between the vertebrae and allows your spine to bend.

There is a hole through each vertebra. The holes line up to make a tunnel called the spinal canal that runs the length of your spine. Your spinal cord lies inside the spinal canal. The vertebrae and spinal canal protect your spinal cord from harm.

The spine is divided into 4 sections from top to bottom. Each section is referred to by a letter.

  • C (cervical)—7 vertebrae in your neck

  • T (thoracic)—12 vertebrae in your upper back that attach to your ribs

  • L (lumbar)—5 vertebrae in your lower back

  • S (sacral)—5 vertebrae that are stuck together making up one bone called the sacrum that attaches your spine to your pelvis

Within each section of the spine, the vertebrae are numbered beginning at the top. When doctors talk about a problem in your spine, they name the letter and number of the vertebrae involved. For example, they may say "L5" if you have a problem in the 5th lumbar vertebra.

How the Spine Is Organized

A column of bones called vertebrae make up the spine (spinal column). The vertebrae protect the spinal cord, a long, fragile structure contained in the spinal canal, which runs through the center of the spine. Between the vertebrae are disks composed of cartilage, which help cushion the spine and give it some flexibility.

How the Spine Is Organized

Spinal nerves: Emerging from the spinal cord between the vertebrae are 31 pairs of spinal nerves. Each nerve emerges in two short branches (roots).

The motor roots carry commands from the brain and spinal cord to other parts of the body, particularly to skeletal muscles.

The sensory roots carry information to the brain from other parts of the body.

Cauda equina: The spinal cord ends about three fourths of the way down the spine, but a bundle of nerves extends beyond the cord. This bundle is called the cauda equina because it resembles a horse's tail. The cauda equina carries nerve impulses to and from the legs.

What is your spinal cord?

Your spinal cord is the thick bundle of nerves that runs from your brain down the inside of your spine (spinal canal). The spinal cord is like an electric cable that carries signals back and forth between your brain and body.

  • Signals from the brain tell your body what to do, such as moving your arms or legs

  • Signals to the brain carry information from your body such as what you're touching or where it hurts

The spinal cord is very delicate, which is why it's protected inside the spinal canal.

The Spine and Spinal Cord

What are spinal nerves?

Spinal nerves are medium-sized nerves that connect your spinal cord to smaller nerves that travel to different parts of your body.

There are 31 pairs of spinal nerves that enter and exit the spinal cord in the spaces between your vertebrae. Each spinal nerve runs from a specific part of the spinal cord to a specific area of your body. So, for example, if you touch a specific spot on your skin, you feel it because of the message sent to your brain by one specific spinal nerve.

What are spine and spinal cord disorders?

Spine disorders

Your spine can be injured from motor vehicle crashes, falls, assaults, and sports injuries. An injury can break your spine bones (spinal fracture) or make them slip out of place (dislocation). The ligaments that hold your spine bones together can tear. Your vertebral discs can rupture.

Sometimes disorders of the spine also affect your spinal cord.

Spinal cord disorders

A spinal cord disorder is any injury or damage to your spinal cord. You may or may not also have a problem with your spine.

What causes a spinal cord disorder?

What are the symptoms of a spinal cord disorder?

When the spinal cord is damaged, the nerves that pass across the damaged area don't work right. In general, a spinal cord disorder causes:

  • Weakness or paralysis (not being able to move part of your body at all)

  • Not being able to feel things such as pain or being touched

  • Loss of control of your bladder and bowels (incontinence)

  • Erectile dysfunction (when a man has problems getting or keeping an erection)

Because the nerves that leave your spinal cord before they get to the damaged area are all right, your symptoms depend on where the spinal cord is damaged. For example, if the spinal cord is damaged in your lower back, you may lose movement and sensation (can't feel pain or someone touching you) in your legs but still be able to use your arms. But if the spinal cord is damaged in your neck, both your arms and legs may be affected. If the spinal cord is damaged high in your neck, you may not be able to breathe. You can lose control of your bladder and bowels and lose sexual function regardless of where your spinal cord is damaged.

If you have damage to your spine bones, ligaments, disks, or spinal nerves, you usually have pain in your neck or back.

You should go to the emergency room right away if you have these symptoms:

  • Suddenly lose feeling in an area of your body

  • Feel weak in one or more of your limbs

  • Aren't able to control when you pee or poop

At first, when you're paralyzed, your muscles are limp. After you've been paralyzed for a while, your muscles tighten up because they're not being used. Your limbs may become so stiff that they cannot bend.

If you are paralyzed or unable to get out of bed, you're at risk of developing other conditions including

Spinal cord disorders can also lead to depression and loss of self-esteem.

How can doctors tell if I have a spinal cord disorder?

How do doctors treat spinal cord disorders?

Doctors treat the cause of the spinal cord disorder, if they can.

Some people can improve with:

  • Surgery—to remove a tumor or fix a fracture

  • Physical therapy—exercising to get stronger and more flexible, learning how to control muscle spasms, learning to use braces, a walker, or wheelchair

  • Occupational therapy—learning how to do your daily tasks with your spinal cord disorder

Talking to a counselor can help if you're struggling to cope with your spinal cord disorder.

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