A spinal cord injury — damage to any part of the spinal cord or nerves at the end of the spinal canal — often causes permanent changes in strength, sensation and other body functions below the site of the injury. The two most common results of severe spinal cord injury are loss of the use of the legs, called paraplegia, or quadriplegia, when the injury is higher on the spinal cord and the use of arms as well as legs are lost. Many scientists are optimistic that advances in research will someday make the repair of spinal cord injuries possible. Research studies are ongoing around the world to regenerate connective nerve tissue through the use of stem cells.