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Updated: Sep 7, 2025

Muscle Velocity Recovery Cycles to Examine Muscle Membrane Properties
Published on: February 19, 2020
[Fasciculations and cramps: physiological bases and clinical approach of a complex phenomenon]
Ignacio Acosta1, Pablo Bastías2, José Manuel Matamala1
1Laboratorio de Neurología y Neurofisiología Traslacional, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
Abstract:
Fasciculations and cramps originate in the motor unit, a functional unit that includes the lower motor neuron and their innervated muscle fibres. Both are common complaints in outpatient practice. These symptoms can be secondary to neurological or medical pathology, presenting a broad differential diagnosis and a complex approach. Recent neurophysiological studies have increased the knowledge of their origin mainly in amyotrophic lateral sclerosis. The symptomatic management of fasciculations and cramps depends on their etiology and includes pharmacological and non-pharmacological treatments. This article aims to present an updated review of the most relevant aspects of physiopathology, clinical approach, and differential diagnosis of both phenomena.
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