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    Primary Lateral Sclerosis

    It is possible that the main title of the report Primary Lateral Sclerosis is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


    • Central Motor Neuron Disease
    • PLS

    Disorder Subdivisions

    • None

    General Discussion

    Primary lateral sclerosis (PLS) is a rare, neuromuscular disorder that affects the central motor neurons and is characterized by painless but progressive weakness and stiffness of the muscles of the legs. Such weakness may progress to affect the arms and the muscles at the base of the brain (bulbar muscles). Less frequently, the muscles of the face are affected. In most cases, the disorder affects adults during midlife. The exact cause of primary lateral sclerosis is unknown.


    Amyotrophic Lateral Sclerosis Association
    27001 Agoura Road
    Suite 250
    Calabasas Hills, CA 91301-5104
    Tel: (818)880-9007
    Fax: (818)880-9006
    Tel: (800)782-4747
    TDD: (818)593-3540

    Motor Neurone Disease Association
    PO Box 246
    Northampton, NN1 2BG
    United Kingdom
    Tel: 01604250505
    Fax: 441604624726

    NIH/National Institute of Neurological Disorders and Stroke
    P.O. Box 5801
    Bethesda, MD 20824
    Tel: (301)496-5751
    Fax: (301)402-2186
    Tel: (800)352-9424
    TDD: (301)468-5981

    Les Turner Amyotrophic Lateral Sclerosis Foundation, Ltd.
    5550 W. Touhy Avenue,
    Suite 302
    Skokie, IL 60077-3254
    Tel: (847)679-3311
    Fax: (847)679-9109
    Tel: (888)257-1107

    Spastic Paraplegia Foundation
    5305 Miramar Ln
    Colleyville, TX 76034
    Tel: (877)773-4483

    International Alliance of ALS/MND Associations
    P.O. Box 246
    Northampton, NN1 2PR
    United Kingdom
    Tel: 441604611821
    Fax: 441604624726

    Genetic and Rare Diseases (GARD) Information Center
    PO Box 8126
    Gaithersburg, MD 20898-8126
    Tel: (301)251-4925
    Fax: (301)251-4911
    Tel: (888)205-2311
    TDD: (888)205-3223

    For a Complete Report:

    This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

    The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

    It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

    This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

    For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

    Last Updated: 8/17/2007
    Copyright 1989, 1992, 2000, 2001, 2002, 2004, 2007 National Organization for Rare Disorders, Inc.

    WebMD Medical Reference from the National Organization for Rare Disorders

    Last Updated: May 28, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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