title: Spontaneous activity in electromyography may differentiate certain benign lower motor neuron disease forms from amyotrophic lateral sclerosis.
abstract: There is limited data on electromyography (EMG) findings in other motor neuron disorders than amyotrophic lateral sclerosis (ALS). We assessed whether the distribution of active denervation detected by EMG, i.e. fibrillations and fasciculations, differs between ALS and slowly progressive motor neuron disorders. We compared the initial EMG findings of 43 clinically confirmed, consecutive ALS patients with those of 41 genetically confirmed Late-onset Spinal Motor Neuronopathy and 14 Spinal and Bulbar Muscular Atrophy patients. Spontaneous activity was more frequently detected in the first dorsal interosseus and deltoid muscles of ALS patients than in patients with the slowly progressive motor neuron diseases. The most important observation was that absent fibrillations in the first dorsal interosseus muscle identified the benign forms with sensitivities of 66%-77% and a specificity of 93%. The distribution of active denervation may help to separate ALS from mimicking disorders at an early stage.
authors.affiliation: Division of Clinical Neurosciences, Turku University Hospital, and University of Turku, Turku, Finland, Kiinamyllynkatu 4-8, 20520 Turku, Finland. Electronic address: manu.jokela@tyks.fi.
authors.forename: Manu E
authors.initials: ME
authors.lastname: Jokela
authors.affiliation: Department of Clinical Neurophysiology, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Satu K
authors.initials: SK
authors.lastname: Jääskeläinen
authors.affiliation: Department of Neurology, Seinäjoki Central Hospital, Seinäjoki, Finland.
authors.forename: Satu
authors.initials: S
authors.lastname: Sandell
authors.affiliation: Neuromuscular Research Center, Tampere University Hospital and University of Tampere, Tampere, Finland.
authors.forename: Johanna
authors.initials: J
authors.lastname: Palmio
authors.affiliation: Neuromuscular Research Center, Tampere University, Tampere, Finland.
authors.forename: Sini
authors.initials: S
authors.lastname: Penttilä
authors.affiliation: Department of Neurology, Central Hospital of Northern Karelia, Joensuu, Finland.
authors.forename: Annamaija
authors.initials: A
authors.lastname: Saukkonen
authors.affiliation: Department of Neurophysiology, Central Hospital of Northern Karelia, Joensuu, Finland.
authors.forename: Raija
authors.initials: R
authors.lastname: Soikkeli
authors.affiliation: Neuromuscular Research Center, Tampere University and Hospital, Tampere, Finland.
authors.forename: Bjarne
authors.initials: B
authors.lastname: Udd
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D024101:Mitochondrial Proteins / Q000235:genetics; D016472:Motor Neuron Disease / Q000473:pathology* / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000503:physiopathology*; D009154:Mutation / Q000235:genetics; D009460:Neurologic Examination; D012189:Retrospective Studies
chemical_list: C554426:CHCHD10 protein, human; D024101:Mitochondrial Proteins
keywords: Amyotrophic lateral sclerosis; CHCHD10; EMG; Fibrillations; SMAJ; Spinal and bulbar muscular atrophy; Spinal muscular atrophy