fasciculation

medical disorder

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Last updated

June 26, 2026

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Fasciculation refers to the simultaneous contraction of contiguous groups of muscle fibers, resulting in a muscular twitch. This is distinct from a cramp, which is a painful, involuntary, and sustained contraction of a muscle. While both involve muscle activity, fasciculations are typically minor twitches, whereas cramps are more intense and prolonged. The term "fasciculate" can also be used as an adjective meaning "fascicular". Muscle diseases can manifest in various ways, including difficulty relaxing muscles after contraction (myotonia) or involuntary muscle spasms.12345

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muscle disease
Indications of muscle disease
…single motor nerve cell, called fasciculation, may occur in a healthy person, but it usually indicates that the muscular atrophy is due to disease of motor nerve cells in the spinal cord. Fasciculation is seen most clearly in muscles close to the surface of the skin.
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…single motor nerve cell, called fasciculation, may occur in a healthy person, but it usually indicates that the muscular atrophy is due to disease of motor nerve cells in the spinal cord. Fasciculation is seen most clearly in muscles close to the surface of the skin.
Read More