title: Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model.
abstract: METHODS
  Animal study.
  
  
  OBJECTIVE
  To review the present warning point criteria of the compound muscle action potential (CMAP) and investigate new criteria for spinal surgery safety using an animal model.
  
  
  BACKGROUND
  Little is known about correlation palesis and amplitude of spinal cord monitoring.
  
  
  METHODS
  After laminectomy of the tenth thoracic spinal lamina, 2-140 g force was delivered to the spinal cord with a tension gage to create a bilateral contusion injury. The study morphology change of the CMAP wave and locomotor scale were evaluated for one month.
  
  
  RESULTS
  Four different types of wave morphology changes were observed: no change, amplitude decrease only, morphology change only, and amplitude and morphology change. Amplitude and morphology changed simultaneously and significantly as the injury force increased (p<0.05) Locomotor scale in the amplitude and morphology group worsened more than the other groups.
  
  
  CONCLUSIONS
  Amplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP.
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Zenya
authors.initials: Z
authors.lastname: Ito
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Imagama
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Ando
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Muramoto
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Hida
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Kenyu
authors.initials: K
authors.lastname: Ito
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Yoshimoto
authors.initials: Y
authors.lastname: Ishikawa
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Mikito
authors.initials: M
authors.lastname: Tsushima
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Akiyuki
authors.initials: A
authors.lastname: Matsumoto
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanaka
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Morozumi
authors.affiliation: Department of Orthopaedic Surgery, Hamamatsu University School of Medicine, Nagoya, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Matsuyama
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishiguro
keywords: Amplitude; Compound muscle action potential; Morphology change