The origin of muscle fasciculations and cramps

  title={The origin of muscle fasciculations and cramps},
  author={Robert B. Layzer},
  journal={Muscle \& Nerve},
  • R. Layzer
  • Published 1 November 1994
  • Biology
  • Muscle & Nerve
The anatomic site of origin of muscle fasciculations and cramps has been debated for many years. Many authors have argued for a central origin of the abnormal discharges in the anterior horn cells. However, most of the evidence favors a very distal origin in the intramuscular motor nerve terminals. The factors giving rise to these discharges are not well understood. Fasciculations may be related to chemical excitation of motor nerve terminals, whereas cramps may result from mechanical… 

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Effects of denervation on fasciculations in human muscle; relation of fibrillations to fasciculations.

IN A previous communication 1 evidence was presented to the effect that fasciculations in voluntary muscle have their site of origin not in the anterior horn cell but at the myoneural junction. This

Synchronous fasciculation in motor neuron disease.

  • F. Norris
  • Biology, Medicine
    Archives of neurology
  • 1965
Denervation by means of nerve resection in three ALS patients abolished fasciculation 8, 11, and 12 days after the operation, which correlates with the time-course of degeneration in the distal nerve branches and provides support for a peripheral axon-reflex mechanism of fasciculations.


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Fasciculations in motor neuron disease: discharge rate reflects extent and recency of collateral sprouting.

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  • Biology
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  • 1984

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  • G. Roth
  • Biology, Medicine
    Annals of neurology
  • 1982
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