1. What is the spinal cord?
The spinal cord is the bundle of nervous tissue (about 18 inches long in men and 17 inches in women) that extends from the medulla of the brain to the first or second lumbar vertebrae—short of extending the length of the vertebral column, as shown in the figure below. The rings of bone surrounding the spinal cord are called vertebrae—as such, the vertebral column protects the spinal cord. The spinal cord is involved in signaling between the brain and the rest of the body, but is also involved in reflexes and other involuntary actions of the Parasympathetic and Sympathetic Nervous Systems.
2. What is Spinal Cord Injury?
Spinal Cord Injury (SCI) is damage to the spinal cord and/or damage to bones, blood vessels, and tissues around the cord. One of the major attributes of SCI is partial or complete loss of functioning, leading to paralysis. SCI can be a result of different causes including
• trauma (car accident, gunshots, shock, falls)
• neurodegenerative or demyelinative diseases
• tumors (gliomas, meningioma)
The location of the injury is directly related to the resulting consequences of the injury. Generally, the higher the injury, the more severe is the loss in functionality. The spinal cord and surrounding vertebral column are shown below and the divided regions are colored as follows:
Damage to a specific location will result in loss of sensation and motor functioning with respect to the attributes of that region and necessarily affecting regions below that location. Injury to the cervical area can correspond with quadriplegia, i.e. loss of function in both arms and legs. Similarly, injury to the thoracic (green) region corresponds to loss of function in the chest and legs. Injury to the lumbar and sacral regions corresponds to effects in the leg and excretory/reproductive areas respectively.