Paralysis, or the inability to move, occurs when nerve cells in the brain or spinal cord are damaged and muscles cannot function properly. A person may become paralyzed because of illness or injury, and paralysis can be temporary or permanent. Paralysis takes many forms and may strike almost any part of the body, ranging from paralysis on one side of the body (hemiplegia) to paralysis in all four limbs (quadriplegia).

Severe trauma to the head, neck, or back—a spinal fracture in a car crash, for example, or a heavy blow to the head—is a common cause of paralysis. Many diseases can also leave victims paralyzed, including cerebral palsy, multiple sclerosis, muscular dystrophy, Guillain-Barré syndrome, and peripheral neuropathy. Brain tumors and strokes can also cause paralysis.

In rare circumstances, paralysis can also be triggered by allergies; drugs; poisons such as botulinum toxin; or mussels, clams, or oysters contaminated with a specific shellfish toxin.

Typically, damage to the left side of the brain causes the right side of the body to become paralyzed, and vice versa. Injuries to the spinal cord in the lower back may result in paralysis of the legs, while an injury higher up in the neck region can result in paralysis of all four limbs. The degree of paralysis depends on which nerve cells are damaged and how much of the brain or spinal cord is involved, how quickly the blood supply returns to the area, and how soon the disease causing the problem is treated. In severe cases, feeding tubes or intravenous feeding may be required. Frequent position changes and good skin care can help maintain muscle tone and prevent complications and tissue atrophy in people who are paralyzed.

ADDITIONAL FACTS

  1. One form of paralysis is called spasticity. People with spasticity can still move, but have reduced control over their muscles and posture and may suffer from spasms.
  2. Polio was a major cause of paralysis in the United States until a vaccine was developed in 1955.
  3. Temporary paralysis may occur when people are transitioning into or out of REM sleep, the stage of sleep in which dreams occur. People experiencing sleep paralysis may be aware of things going on around them but are unable to move or speak.