myotonia

myotonia /myo·to·nia/ (mi″o-to´ne-ah) dystonia involving increased muscular irritability and contractility with decreased power of relaxation.myoton´ic

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myotonia atro´phica  myotonic dystrophy.

myotonia conge´nita  a hereditary disease marked by tonic spasm and rigidity of certain muscles when attempts are made to move them after rest or when they are mechanically stimulated.

myotonia dystro´phica  myotonic dystrophy.

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my·o·to·ni·a (m-tn-)

n.

Delayed relaxation of a muscle after an initial contraction.

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myo·tonic (-tnk) adj.

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myotonia

[mī′ətō′nē·ə]

Etymology: Gk, mys + tonos, tone

any condition in which a muscle or a group of muscles does not readily relax after contracting. myotonic, adj. Compare amyotonia.

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myotonia (mi″oto´ne),

n a condition in which muscles remain tense or do not quickly relax after contraction.

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myotonia

any disorder involving tonic spasm of muscle.

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acquired myotonia

see pseudomyotonia.

myotonia congenita

an inherited muscle stiffness with stilted gait that worsens with excitement is observed from a few months of age in Chow Chows, Labrador retrievers and Irish terriers.

equine myotonia

is manifest with a stiff gait, hypertrophy of the proximal appendicular musculature and percussion of muscle produces sustained contraction. It may be inherited in some Quarter horse lines.

inherited congenital myotonia

a disease of goats, characterized by inability to move quickly. The limbs become rigid due to muscle contraction, but after a few minutes rest the animal is able to move normally. It is similar to myotonia congenita in humans.

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myotonia

Neurology Delayed muscle relaxation after voluntary contraction–action myotonia or mechanical stimulation–percussion myotonia Types Chloride channel-related disorders–eg, myotonia congenita, Thomsen type; protein kinase-related disorders–eg, myotonic dystrophy; sodium channel-related disorders–eg, hyperkalemic periodic paralysis; idiopathic