title: New mathematical approach for approximating the baseline of F-waves using spreadsheet software.
abstract: OBJECTIVE
  The aim of this study was to see if curved baselines of F-waves could be mathematically approximated with universal spreadsheet software.
  
  
  METHODS
  The subjects were 3 healthy persons and 3 patients with cervical myelopathy. Supramaximal electrical stimuli were applied 200 times to the median nerve at the wrist. Compound muscle action potentials (CMAPs) of the abductor pollicis brevis were recorded. To make polynomial approximation equations that represent latter part of the M-waves, records without F-waves were analyzed.
  
  
  RESULTS
  There were 193 CMAPs without F-waves out of all 1,200 records. Polynomial equations were made for each record. Determinant coefficients for all the approximation equations were greater than 0.998, and the overall standard deviation of the difference between original data and approximated value was 3.05 microV.
  
  
  CONCLUSIONS
  Curved baselines of F-waves were represented by approximation curves. Baselines of the F-waves could be approximated as flat lines by subtracting calculated values from the original data.
  
  
  CONCLUSIONS
  This method was useful for analyzing waveforms of F-waves.
authors.affiliation: Division for Restorative Medicine of Neuro-muscuroskeletal System, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan. konno@nms.ac.jp
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Konno
authors.forename: Takafumi
authors.initials: T
authors.lastname: Aoki
authors.forename: Hiromoto
authors.initials: H
authors.lastname: Ito
mesh_terms: D002574:Cervical Vertebrae; D004576:Electromyography / Q000379:methods*; D005071:Evoked Potentials; D006801:Humans; D008432:Mathematical Computing; D018482:Muscle, Skeletal / Q000502:physiology* / Q000503:physiopathology*; D012044:Regression Analysis; D012984:Software; D013118:Spinal Cord Diseases / Q000503:physiopathology; D034941:Upper Extremity