Fasciculation

Fasciculations are involuntary movements of very small muscle groups ( muscle bundles ), which are visible under the skin, but do not lead to substantial movement effect. They are not painful and can often be provoked by tapping or pinching the muscle.

Benign fasciculation

(→ Main article Benign fasciculation )

These benign ( benign ) fasciculations often occur on the face or the extremities. This leads eg to a short twitch of the eyelid or hand, but which can be repeated several times. The feeling here can range from vibrations in muscle fibers to motor effective muscle spasms (such as also falling asleep ). This has no clinical significance, although it can be annoying in some cases. Mental imbalance, stress and intake of stimulants can trigger or exacerbate fasciculations.

Pathological fasciculations

This type of fasciculations are much less common than benign fasciculations and come as a symptom, especially in diseases with a downfall of α - motor neurons before (eg, amyotrophic lateral sclerosis ). When damage to the peripheral nervous fasciculations may occur in the paralyzed muscle.

Fasciculations are, inter alia in amyotrophic lateral sclerosis, poliomyelitis, a cervical spine degeneration, polyneuropathy (for example, diabetes mellitus), myopathy (eg, polymyositis ) or impaired electrolyte balance, such as hyponatremia or hypomagnesemia, with hypocalcemia or hypokalemia can cause cramping and tetany before. It is also possible drugs or medications, for example, Acetylcholinesterase ( works primarily in the CNS ) or containing lithium, act as a trigger for fasciculations.

In combination with muscle atrophy or muscle weakness, fasciculations can point to such a disease.

The diagnostic detection of fasciculation is made by electromyography in the form of Faszikulationspotentialen. These are known as typical potentials derived at rest ( " pathological spontaneous activity "). Alone electrophysiologically these potentials are indistinguishable from benign fasciculations, but also to evaluate here only in connection with other pathological changes. The electromyogram is typically expressed as fasciculations biphasic potentials with high amplitude.

Fasciculations without other neurological symptoms are almost always benign fasciculations.

Demarcation

• Fibrillation - short twitching of muscle fibers
• Fasciculation - short Muskelbündelzuckung without motion effect
• Myoclonus - muscle twitch with or without motion effect
• Tremor - periodic reciprocating motion (shaking)
• Dystonia - prolonged muscle spasm
• Myokymia - superficial, localized wave-like muscle contraction