title: Motor unit number estimation and quantitative needle electromyography in stroke patients.
abstract: OBJECTIVE
  To evaluate the effect of upper motor neuron damage upon motor units' function by means of two separate and supplementary electrophysiological methods.
  
  
  METHODS
  The abductor digiti minimi muscle of the non-paretic and the paretic side was studied in forty-six stroke patients with (a) motor unit number estimation (MUNE) - adapted multiple point stimulation method and (b) computerized quantitative needle electromyography (EMG) assessing the configuration of voluntary recruited motor unit potentials. Main outcome comparisons were focused on differences between non-paretic and paretic side.
  
  
  RESULTS
  On the affected hands mean MUNE value was significantly lower and mean area of the surface recorded single motor unit potentials was significantly larger than the corresponding ones on the non-paretic hands. EMG findings did not reveal remarkable differences between the two sides. Neither severity nor chronicity of stroke was related to MUNE or EMG parameters.
  
  
  CONCLUSIONS
  MUNE results, which suggested reduced motor unit numbers in stroke patients, in conjunction with the normal EMG features in these same muscles has given rise to different interpretations. In a clinical setting, reinnervation type changes in the EMG similar to that occurring in neuronopathies or axonal neuropathies should not be expected in muscles with central neurogenic lesion.
authors.affiliation: Departments of Neurology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: Ioanna
authors.initials: I
authors.lastname: Kouzi
authors.affiliation: Departments of Neurology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: Eftichia
authors.initials: E
authors.lastname: Trachani
authors.affiliation: Departments of Neurology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: Evangelos
authors.initials: E
authors.lastname: Anagnostou
authors.affiliation: Departments of Spinal Cord Lesions Rehabilitation, School of Medicine, University of Patras, Patras, Greece.
authors.forename: Christina-Anastasia
authors.initials: CA
authors.lastname: Rapidi
authors.affiliation: Departments of Neurology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: John
authors.initials: J
authors.lastname: Ellul
authors.affiliation: Departments of Medical Physics, School of Medicine, University of Patras, Patras, Greece.
authors.forename: George C
authors.initials: GC
authors.lastname: Sakellaropoulos
authors.affiliation: Departments of Neurology, School of Medicine, University of Patras, Patras, Greece. Electronic address: echroni@yahoo.com.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Chroni
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004576:Electromyography / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D009339:Needles; D011999:Recruitment, Neurophysiological / Q000502:physiology*; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology*
keywords: Electromyography; Hemiparesis; Motor unit potentials; Motor units number estimation; Stroke; Upper and lower motor neuron