A spinal cord injury (SCI) results when any type of trauma damages nervous tissue of the spinal cord. These nerves are responsible for carrying signals between the brain and the rest of the body. Serious spinal cord injuries can result in permanent, partial or complete paralysis.

The spinal cord runs from the base of the brain down to the small of the back. Ring-shaped bones called vertebrae form the spine, which surrounds the spinal cord and protects it from injury. When these bones are broken or otherwise damaged, they can cause injury to the neurons and axons (nerve fibers) of the spinal cord. These nerve cells are part of the central nervous system and do not regenerate after they are injured. Such injuries can cause varying levels of paralysis.

Spinal cord injuries occur most often in the neck and lower back. The location of the injury on the spine determines how much the transmission of nerve signals to the brain is interrupted. In general, the higher up the spinal cord a person is injured, the more severe the injury is likely to be. Spinal cord injuries are divided into two types:

• Incomplete injury. People with these injuries retain some motor or sensory function below the level of the injury. One side of the body may be more affected than the other.
  
  
• Complete injury. Involves a total lack of sensory or motor function below the level of the injury. In most cases, both sides of the body are equally affected.

In most cases, SCIs result from a sudden and significant trauma to the spine. This most often occurs as a result of automobile accidents, acts of violence (e.g., gunshot wounds), accidental falls and injuries sustained during sports activities (especially diving accidents). In younger adults, automobile accidents are the leading cause of SCIs. In older adults, accidental falls most often cause SCIs. Men sustain SCIs more often than women.  

More than 200,000 Americans are living with SCIs, according to the National Institute of Neurological Disorders and Stroke (NINDS). Each year, more than 10,000 new cases of SCI occur, two-thirds of which strike people under 30.

An injury to the spinal cord can cause a variety of symptoms. Patients often experience an intense stinging sensation caused by damage to nerve fibers in the spinal cord. Loss of movement, loss of sensation (e.g., ability to feel heat, cold and touch) and loss of bodily functions (e.g., bladder and bowel control) also are typical symptoms of an SCI.

People who are not medical experts should be extremely careful when trying to provide first aid to a person who may have sustained an SCI. It is especially crucial not to move the affected person. Doing so can result in worsened permanent damage and other complications.

After the patient is brought to an emergency room, a physician will carefully inspect the body to look for signs of an SCI. Imaging tests also help reveal the extent of a patient’s injuries. Various treatments are available for people who have experienced an SCI, including neck and spine bracing, medications, surgery, physical therapy and mental health counseling.

While spinal cord injuries cannot always be prevented, people can take steps to reduce their risk of experiencing such trauma. These measures include driving safely, using care around firearms and wearing protective equipment when participating in sports.  

Research continues into ways to help patients to regain movement ability following SCIs. This includes nerve regeneration research and electrical stimulation devices that may help restore lost motor or sensory functions.