The spinal cord is a vital part of your nervous system. It relays messages between the brain and body. Problems with the spinal cord can cause a loss of sensation and movement. Spinal cord injury (SCI) is often due to injury, such as a car accident. But injury isn't the only cause of damage to the spinal cord. Certain illnesses and conditions can also cause it. These are known as spinal cord disorders or diseases. This sheet outlines the most common types of spinal cord diseases.