The motor neuron diseases (MNDs) are a group of progressive neurological disorders that destroy cells that control essential muscle activity such as speaking, walking, breathing, and swallowing. Normally, messages from nerve cells in the brain (called upper motor neurons) are transmitted to nerve cells in the brain stem and spinal cord (called lower motor neurons) and from them to particular muscles. When there are disruptions in these signals, the result can be gradual muscle weakening, wasting away, and uncontrollable twitching (called fasciculations). Eventually, the ability to control voluntary movement can be lost. MNDs may be inherited or acquired, and they occur in all age groups. In adults, symptoms often appear after age 40. In children, particularly in inherited or familial forms of the disease, symptoms can be present at birth or appear before the child learns to walk.
The causes of sporadic (noninherited) MNDs are not known, but environmental, toxic, viral, or genetic factors may be implicated. Common MNDs include amyotrophic lateral sclerosis (ALS), progressive bulbar palsy, primary lateral sclerosis, and progressive muscular atrophy. Other MNDs include the many inherited forms of spinal muscular atrophy and post-polio syndrome, a condition that can strike polio survivors decades after their recovery from poliomyelitis.
There is no cure or standard treatment for the MNDs. Symptomatic and supportive treatment can help patients be more comfortable
while maintaining their quality of life. The drug riluzole (Rilutek®), which as of this date is the only drug approved by
the U.S. Food and Drug Administration to treat ALS, prolongs life by 2-3 months but does not relieve symptoms. Other medicines
that may help reduce symptoms include muscle relaxants such as baclofen, tizanidine, and the benzodiazepines for spasticity;
glycopyrrolate and atropine to reduce the flow of saliva; quinine or phenytoin for cramps; anticonvulsants and nonsteroidal
anti-inflammatory drugs to relieve pain; tranquilizers to help with sleeping problems; antidepressants; and botulinum toxin,
amitriptyline, and other anticholinergic drugs to control drooling. Some patients may require stronger medicines such as
morphine to cope with musculoskeletal abnormalities or pain in later stages of the disorders, and opiates are used to provide
comfort care in terminal stages of the disease.
Physical and speech therapy, occupational therapy, and rehabilitation may help to improve posture, prevent joint immobility,
slow muscle weakness and atrophy, and cope with swallowing difficulties. Applying heat may relieve muscle pain. Assistive
devices such as supports or braces, orthotics, speech synthesizers, and wheelchairs help some patients retain independence.
Prognosis varies depending on the type of MND and the age of onset. Some MNDs, such as primary lateral sclerosis, are not
fatal and progress slowly. Patients with spinal muscular atrophy may appear to be stable for long periods, but improvement
should not be expected. Some MNDs, such as ALS and some forms of spinal muscular atrophy, are fatal.
ALS Association 27001 Agoura Road Suite 150 Calabasas Hills, CA 91301-5104 advocacy@alsa-national.org http://www.alsa.org Tel: 818-880-9007 800-782-4747 Fax: 818-880-9006 |
Muscular Dystrophy Association 3300 East Sunrise Drive Tucson, AZ 85718-3208 mda@mdausa.org http://www.mda.org Tel: 520-529-2000 800-344-4863 Fax: 520-529-5300 |
ALS Therapy Development Institute 215 First Street Cambridge, MA 02142 info@als.net http://www.als.net Tel: 617-441-7200 Fax: 617-441-7299 |
Les Turner ALS Foundation 5550 W. Touhy Avenue Suite 302 Skokie, IL 60077-3254 info@lesturnerals.org http://www.lesturnerals.org Tel: 888-ALS-1107 847-679-3311 Fax: 847-679-9109 |
Project ALS 900 Broadway Suite 901 New York, NY 10003 info@projectals.org http://www.projectals.org Tel: 212-420-7382 800-603-0270 Fax: 212-420-7387 |
Spastic Paraplegia Foundation Spastic Paraplegia Foundation PO Box 1208 Fortson, GA 31808 Phone: 877-773-4483 Email: information@sp-foundation.org www.sp-foundation.org Suite 123 Falls Church, VA 22043 information@sp-foundation.org http://www.sp-foundation.org Tel: 1-877-SPF-GIVE (1-877-773-4483) Fax: 877-SPF-GIVE |
Synapse: A PLS Newsletter 212 Farm Road Sherborn, MA 01770 synapsePLS@comcast.net http://synapsepls.org Tel: 508-653-5246 |
Families of Spinal Muscular Atrophy P.O. Box 196 Libertyville, IL 60048-0196 info@fsma.org http://www.curesma.org Tel: 800-886-1762 Fax: 847-367-7623 |
FightSMA/Andrew's Buddies 1807 Libbie Avenue Suite 104 Richmond, VA 23226 heatherlennon@fightsma.com http://www.fightsma.org Tel: 804-515-0080 Fax: 804-515-0081 |
Kennedy's Disease Association P.O. Box 1105 Coarsegold, CA 93614-1105 info@kennedysdisease.org http://www.kennedysdisease.org Tel: 559-658-5950 |
Spinal Muscular Atrophy Foundation 888 Seventh Avenue Suite 400 New York, NY 10019 info@smafoundation.org http://www.smafoundation.org Tel: 877-FUND-SMA (877-386-3762) 646-253-7100 Fax: 212-247-3079 |
Post-Polio Health International/ 4207 Lindell Blvd. #110 St. Louis, MO 63108-2930 info@post-polio.org http://www.post-polio.org Tel: 314-534-0475 Fax: 314-534-5070 |
Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.
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Last updated September 09, 2008