paraplegia (pârˌəplēˈjēə) [key], paralysis of the lower part of the body, commonly affecting both legs and often internal organs below the waist. When both legs and arms are affected, the condition is called quadriplegia. Paraplegia and quadriplegia are caused by an injury or disease that damages the spinal cord, and consequently always affects both sides of the body. The extent of the paralysis depends on the level of the spinal cord at which the damage occurs. For example, damage to the lowest area of the cord may result only in paralysis of the legs, whereas damage farther up on the cord causes possible loss of control over the muscles of the bladder and rectum as well or, if occurring even higher, may result in paralysis of all four limbs and loss of control over the muscles involved in breathing.
Most frequently the cause is an injury that either completely severs the spinal cord or damages some of the nervous tissue in the cord. Such damage could result from broken vertebrae that press against the cord. Diseases that cause paraplegia or quadriplegia include spinal tuberculosis, syphilis, spinal tumors, multiple sclerosis, and poliomyelitis. Sometimes when the disease is treated and cured, the paralysis disappears, but usually the nerve damage is irreparable and paralysis is permanent. Treatment of paraplegia and quadriplegia is aimed at helping to compensate for the paralysis by means of mechanical devices and through psychological and physical therapy.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.