Chronic spinal cord injury refers to a permanent and/or progressive interruption in the conduction of impulses across the neurons and tracts of the spinal cord. It may be due to mechanical distortion or vascular ischemia of the spinal cord arising from trauma, tumor, infection, or other space-occupying lesions. The term is generally used when elements of spinal cord injury have been present for at least 1 year. Commensurate neurologic deficits occur that may be stable or progressive and lead to disability with spasticity, joint contractures, sensory changes, and sphincter and locomotion abnormalities.