Quadriplegic cerebral palsy is one form of cerebral palsy. It is characterized by the lack of ability to move or to feel in both legs and both arms of the body, and often affects other areas of the body as well. This condition is caused by an injury to the spinal cord, in most situations. The spinal cord sends messages to and from the brain to the body parts to control movement and to control sensation. Of the types of cerebral palsy, quadriplegic cerebral palsy, often called quadriplegia, is the most severe. Many individuals who suffer from this form also suffer from difficulty speaking, mental retardation, difficulty controlling the muscles in the mouth, hemiparetic tremors and in some cases uncontrollable shaking.