fasciculation (muscle twitching)

Introduction

A minor muscle contraction & relaxation of a muscle group that is served by a single motor nerve fiber. (Lower motor neuron sign)

Etiology

• diet deficiency
• excess caffeine
• adverse drug effects (diuretics, corticosteroids, estrogens)
• exercise
• stress, anxiety
• generally episodic & do not last more than a few days
• nervous system disease
  • amyotrophic lateral sclerosis
  • peripheral nerve injury
  • muscular dystrophy
  • spinal muscular atrophy
  • muscle weakness, myopathy

Epidemiology

• common

Clinical manifestations

• often go unnoticed
• often affect the eyelids, calf, or thumb
• symptoms that suggest nervous system disease:
  • loss or change in sensation
  • muscle wasting
  • muscle weakness
  • peripheral nerve injury results in fine, rapid flickering or coarse muscle twitching, originating in small groups of muscle fibers, associated with muscle atrophy

Management

• generally no treatment necessary for benign fasciculation
• see specific disorder for pathologic fasciculations

More general terms

• sign/symptom

Additional terms

• tic disorder