title: Motor unit number estimations are smaller in children with type 1 diabetes mellitus: A case-cohort study.
abstract: BACKGROUND
  We studied the potential for motor unit number estimation (MUNE) to detect subclinical changes in motor unit numbers in children with type 1 diabetes mellitus (DM).
  
  
  METHODS
  Blinded observers performed clinical assessment, electrophysiology, and multipoint MUNE of the extensor digitorum brevis muscle in children with DM for ≥ 5 years and age-matched healthy controls.
  
  
  RESULTS
  For 51 DM subjects, the disease duration was 9.1 ± 2.6 years. Subjects with DM and healthy controls (n=21) had similar demographics. There were no clinical symptoms or signs of peripheral neuropathy in any subject, nor differences in standard electrophysiology between cohorts. Estimated motor unit numbers were decreased significantly in children with DM (224 ± 87 vs. 274 ± 101, P=0.036).
  
  
  CONCLUSIONS
  Despite the absence of clinical or standard electrophysiological differences from normal control subjects, MUNE can detect a small significant difference in children with DM, suggesting that motor unit loss begins early and subclinically in the disease.
authors.affiliation: Department of Clinical Neurosciences and the Hotchkiss Brain Institute, HMRB 155, Foothills Hospital, Canada University of Calgary, 1403 29 Street NW, Calgary, Alberta, T2N 2B1, Canada.
authors.forename: Cory
authors.initials: C
authors.lastname: Toth
authors.forename: Valerie
authors.initials: V
authors.lastname: Hebert
authors.forename: Claire
authors.initials: C
authors.lastname: Gougeon
authors.forename: Heidi
authors.initials: H
authors.lastname: Virtanen
authors.forename: Jean K
authors.initials: JK
authors.lastname: Mah
authors.forename: Daniele
authors.initials: D
authors.lastname: Pacaud
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D009046:Motor Neurons / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation*; D010525:Peripheral Nerves / Q000503:physiopathology; D010523:Peripheral Nervous System Diseases / Q000209:etiology* / Q000473:pathology*; D012044:Regression Analysis
keywords: diabetes mellitus; electrophysiology; juvenile diabetes mellitus; motor unit number estimation; peripheral neuropathy