Muscle fasciculations

Muscle fasciculations or muscle twitches are small, local, involuntary muscle contractions in skeletal muscles. Superficial muscle fasciculations are visible to the eye. Deeper muscle fasciculations are detected by electromyography (EMG) testing. They result from an involuntary firing of a single motor neuron (nerve cell) and all its innervated muscle fibers.

Muscle fasciculations can occur in healthy people especially in the eyelid muscles, and are considered benign, however, when fasciculations are accompanied by muscle weakness or atrophy, these fasciculations may indicate a neurological dysfunction.

Prevalence

 * In a 2001 Belgian study, 58.5% of patients meeting the Fukuda criteria and 64.1% of patients meeting the Holmes criteria, in a cohort of 2073 CFS patients, reported muscle fasciculations.

Symptom recognition
The Canadian Consensus Criteria lists muscle fasciculations as a symptom of ME/CFS under the section Neurological/Cognitive Manifestations.