Myotonia is a medical term that refers to a neuromuscular condition in which the relaxation of a muscle is impaired. It can affect any muscle group. Repeated effort will be needed to relax the muscle, although the condition usually improves after the muscles have warmed-up. Individuals with myotonia may have trouble releasing their grip on objects or may have difficulty rising from a seated position. They may walk with a stiff, awkward gait. Myotonia is caused by an abnormality in the muscle membrane, and is often associated with inherited neurological disorders. Myotonia is commonly seen in individuals with myotonic muscular dystrophy, myotonia congenita, and in people who have one of a group of neurological disorders called the channelopathies, which are inherited diseases that are caused by mutations in the chloride sodium or potassium channels that regulate the muscle membrane. Myotonia may also be triggered by exposure to cold.
National Institute of Arthritis and
Musculoskeletal and Skin Diseases (NIAMS) National Institutes of Health, DHHS 31 Center Dr., Rm. 4C02 MSC 2350 Bethesda, MD 20892-2350 NIAMSinfo@mail.nih.gov http://www.niams.nih.gov Tel: 301-496-8190 877-22-NIAMS (226-4267) |
Muscular Dystrophy Association 3300 East Sunrise Drive Tucson, AZ 85718-3208 mda@mdausa.org http://www.mda.org Tel: 520-529-2000 800-572-1717 Fax: 520-529-5300 |
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.
All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.
Last updated September 30, 2011