title: Electrical impedance myography in the diagnosis of radiculopathy.
abstract: BACKGROUND
  We sought to determine whether electrical impedance myography (EIM) could serve as a diagnostic procedure for evaluation of radiculopathy.
  
  
  METHODS
  Twenty-seven patients with clinically and radiologically diagnosed cervical or lumbosacral radiculopathy who met a "gold standard" definition underwent EIM and standard needle electromyography (EMG) of multiple upper or lower extremity muscles.
  
  
  RESULTS
  EIM reactance values revealed consistent reductions in the radiculopathy-affected myotomal muscles as compared with those on the unaffected side; the degree of asymmetry was associated strongly with the degree of EMG abnormality (P < 0.001). EIM had a sensitivity of 64.5% and a specificity of 77.0%; in comparison, EMG had a sensitivity of 79.7% but a specificity of 69.7%.
  
  
  CONCLUSIONS
  These findings support the potential for EIM to serve as a new non-invasive tool to assist in diagnosis of radiculopathy; however, further refinement of the technique is needed for this specific application.
authors.affiliation: Department of Neurology, Beth Israel Deaconness Medical Center, 330 Brookline Avenue, Boston, Massachusetts, 02215, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Spieker
authors.forename: Pushpa
authors.initials: P
authors.lastname: Narayanaswami
authors.forename: Laura
authors.initials: L
authors.lastname: Fleming
authors.forename: John C
authors.initials: JC
authors.lastname: Keel
authors.forename: Stefan C
authors.initials: SC
authors.lastname: Muzin
authors.forename: Seward B
authors.initials: SB
authors.lastname: Rutkove
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000294:innervation; D017097:Electric Impedance; D004576:Electromyography / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000294:innervation / Q000503:physiopathology*; D008161:Lumbosacral Region / Q000294:innervation; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology*; D009339:Needles / Q000706:statistics & numerical data; D011843:Radiculopathy / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
keywords: cervical radiculopathy; electrical impedance; electromyography; lumbosacral radiculopathy; muscle; reactance