title: Clinical utility of trapezius muscle studies in the evaluation of amyotrophic lateral sclerosis.
abstract: Needle electromyography (EMG) and determining the motor evoked potential (MEP) of the genioglossus (tongue) are difficult to perform in evaluation of the craniobulbar region in patients with amyotrophic lateral sclerosis (ALS). Needle EMG and MEP determination in the upper trapezius were carried out in 17 consecutive ALS patients. The needle EMG parameters recorded included abnormal spontaneous activity and motor unit action potential morphology. An upper motor neuron lesion was presumed when either response to cortical stimulation was absent, or the central conduction time was delayed (>mean + 2 SD). Of the 12 patients with limb-onset ALS, using needle EMG, 11 were found to have abnormalities in the upper trapezius, and only five in the tongue. Three of the six patients with isolated limb involvement had abnormal MEP findings. In conclusion, electrophysiological studies of the upper trapezius are useful in ALS patients without bulbar symptoms.
authors.affiliation: Department of Neurology, Ilsan Paik Hospital, Inje University College of Medicine, Ilsan, Korea.
authors.forename: Joong-Yang
authors.initials: JY
authors.lastname: Cho
authors.forename: Jung Joon
authors.initials: JJ
authors.lastname: Sung
authors.forename: Ju-Hong
authors.initials: JH
authors.lastname: Min
authors.forename: Kwang-Woo
authors.initials: KW
authors.lastname: Lee
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000503:physiopathology*; D004576:Electromyography / Q000379:methods*; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011712:Pyramidal Tracts / Q000503:physiopathology; D011930:Reaction Time / Q000502:physiology; D050781:Transcranial Magnetic Stimulation / Q000379:methods*