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Tonic muscular spasm occurring after injury or infection.



a hereditary neuromuscular disease in which a contracted muscle is unable to relax for a long time; muscular relaxation proceeds very slowly. Depending on the clinical course of the disease, congenital, atrophic, cold, and paradoxical forms of myotonia are distinguished. The disease may occur in several members of a family; males are more often affected. There are no marked morphological changes in the nervous system or the muscles. There may be dysfunctions of the autonomic nervous system and the endocrine glands. Increased sensitivity to acetylcholine and potassium are characteristic of the disease. The principal sign of myotonia is impaired myofibril contractility, that is, relaxation of contracted muscles is greatly impaired. The muscles are firm to the touch. Myotonia progresses slowly, with general deterioration frequently setting in after overexposure to low temperatures, mental stress, and excessive fatigue. Treatment includes hormone therapy, vitamin therapy, and physical therapy.


Badalian, L. O., V. A. Tabolin, and Iu. V. Vel’tishchev. Nasledstvennye bolezni u detei. Moscow, 1971.
References in periodicals archive ?
Besides, warm-up phenomena and grips myotonia were demonstrated.
Mutations in CLCN1 gene have been shown to cause congenital myotonia.
At the same time the baby started having mild grade muscle stiffness and myotonia, while weight and the height of the baby for his age was below normal.
28) In addition, chloroquine can cause a myasthenia-like syndrome or myotonia.
A histochemical and ultrastructural study in the goat: Comparison with abnormalities found in human myotonia dystrophica.
A few disorders, including CMT 4F, myotonia congenita, and spastic paraplegia type 4, were associated with costs of -$2000.
Her older sister Toni-Jayne, 12, has global development delay, autistic tendencies and muscle problems, and Sophie-Leigh, nine, has myotonia and is still in nappies.
For example, myotonic dystrophy has a broad spectrum of presentation varying from congenital myotonia to the seventh decade of life.
It causes muscular atrophy myotonia, cardiac conduction disturbances that can lead to arrhythmias, cataracts, diabetes, testicular atrophy and pregnancy complications.
Among men, normal physiological changes associated with age include reductions in penile myotonia (muscle tension) during sexual arousal.