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Spinal Cord Injury Basics

The spinal cord connects the base of the brain to the body’s nerves, making it an important communication highway between the brain and the rest of the body.

It is surrounded and protected by a bony canal, which is part of the spinal column (also known as the spine or backbone).

A spinal cord injury happens when the spinal column fractures or when the ligaments holding the spinal column together fall out of alignment. As a result, the spinal cord within the bony canal may be bruised or crushed.

This injury interrupts the communication between the brain and the parts of the body below the site or level of injury.

What Is a Spinal Cord Injury?

An SCI is damage to the column of nerves that sends signals from the brain to other body parts. These vital nerves branch off from the spinal cord and affect muscles and feeling in the legs, arms, and body.

SCIs can cause people to lose the ability to perform basic functions, such as:

  • Walking.
  • Eating.
  • Talking.

The effects of SCIs vary, depending on which nerves in the spinal cord you damaged. Also, the degree of loss of body functions depends on how severe the injury is.

If you've severed or completely cut the spinal cord, you'll lose function from any of the nerves below the injury site.

Spinal cord injury types

The American Spinal Injury Association (ASIA) labels SCIs as either complete or incomplete.

A complete SCI means the injury has severed the spinal cord, cutting off the nerves below it. This means there's no possibility for function below the site of the SCI.

Doctors call this an ASIA A injury.

An incomplete injury damages the nerve in the spine but doesn't sever the spinal cord.

Doctors further classify incomplete SCIs based on the extent of injury:

  • ASIA B injury. You have some feeling but no motor function from the nerves below the SCI site.
  • ASIA C injury. You have sensation and some movement. You can move less than half the muscle groups affected by spinal nerves below the injury.
  • ASIA D. You have some feeling and greater movement than ASIA C. You can move more than half the muscle groups affected by spinal nerves below the SCI.

Doctors also label SCIs based on the injured nerve and part of the spine:

  • Cervical (top part) spine.
  • Thoracic (upper-mid part) spine.
  • Lumbar (lower-mid part) spine.
  • Sacral (bottom part) spine.

For instance, a cervical spine injury to the:

  • First nerve is a C1 injury.
  • Fourth nerve is a C4 injury.

Likewise, a thoracic spine injury to the first nerve is a T14 injury.

Cervical SCIs cause the most severe impairment, followed by thoracic SCIs.

Spinal cord injury causes

SCIs most often result from:

  • Motor vehicle accidents (the #1 cause of SCIs).
  • Falls (the leading cause for people over 65).
  • Gunshot or knife wounds.
  • Sports injuries, such as from diving into a shallow pool or tackling in football.
  • Medical causes (e.g., tumors or swelling that puts pressure on the spinal nerves).

Spinal cord injury risk factors

Knowing you have one or more risk factors can help you prevent or lower your risk of an SCI.

These include:

  • Being a young male adult. More than half of SCIs happen between ages 16 and 30. Men make up 80%.
  • Having osteoporosis. This can weaken spinal bones and cause more nerve damage if you fall.
  • Being over 65. People over 65 are more likely to fall due to lower muscle tone, poorer eyesight, and other reasons. They're also more likely to get hurt when they fall.
  • Taking part in higher-risk sports like football, rugby, skiing, or snowboarding.

Spinal cord injury complications

For most people, SCIs are life-changing.

The health impacts can range from somewhat minor to extremely severe. It depends on the injury site and if it's a complete or an incomplete SCI.

Complications of SCIs can include:

  • Trouble breathing.
  • Heart problems, such as a slow heartbeat or low blood pressure.
  • Urinary tract infections.
  • Digestive issues, such as constipation or inability to control the bowels.
  • Decreased sexual function.
  • Chronic pain.
  • Pressure sores.
  • Depression or social anxiety.

Your care team will watch for any of these complications. They can help you take steps to avoid them and can treat them if they do occur.

How to prevent a spinal cord injury

Motor vehicle wrecks cause most SCIs.

You can prevent them by:

  • Always wearing a seatbelt.
  • Never texting or doing other distracting tasks when driving.
  • Never driving under the influence of alcohol or drugs.
  • Never riding with someone who is driving under the influence.

Falls are another common cause of SCIs, especially among seniors.

To reduce your chances of falling:

  • Keep the floor clear of clutter.
  • Install grab bars in the bathroom.
  • Stay active to keep muscles strong and decrease the risk of osteoporosis.
  • Talk to your doctor about reducing or stopping medicine that may cause drowsiness or confusion.

Here are other steps you can take to prevent injury to yourself or others:

  • Wear proper protective equipment — such as a helmet and padding — during sports and recreational activities.
  • Never dive into a body of water without being sure it's deep enough (ideally at least 10 feet deep).
  • Don't dive into water without being certain that there are no rocks or other hard objects below the surface.
  • Practice gun safety, including locking up guns in a safe place.
  • Avoid extreme sports, such as bungee jumping and skydiving.

Lastly, never move someone who may have a severe injury or trauma to the spine. Moving them can make a spinal cord injury far worse.

Let emergency responders assess and move the person.

Spinal cord injury diagnosis

Doctors diagnose SCIs by:

  • Testing your response to touch at various points in the body.
  • Asking you to try to move different muscle groups to see which nerves you damaged and by how much.
  • Ordering imaging tests such as a CT scan, an x-ray, an MRI, or a combination of these. These tests help the doctor see the bones, spinal disks, and blood clots or tumors that can damage nerves.