Fasciculations
Fasciculations are a characteristic feature of motor neuron disease. They can occur in any chronic denervating process but when this widespread and when accompanied by such weakness and atrophy the diagnosis of motor neuron disease is inescapable. Early in the disease ultrasound may detect fasciculations that are not as obvious by clinical examination.
References
Campbell WW. Clinical signs in neurology : a compendium. Philadelphia: Wolters Kluwer Health, 2016.
Campbell WW. DeJong's the neurologic examination, 7th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2013. de Carvalho M, Swash M. Origin of fasciculations in amyotrophic lateral sclerosis and benign fasciculation syndrome. JAMA Neurol. 2013;70:1562-5.
Mills KR. Characteristics of fasciculations in amyotrophic lateral sclerosis and the benign fasciculation syndrome. Brain. 2010;133:3458-69.
Swash M, Carvalho Md. Muscle ultrasound detects fasciculations and facilitates diagnosis in ALS. Neurology. 2011;77:1508-9.