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Updated: Mar 28, 2026

In Vivo Electrophysiological Measurement of Compound Muscle Action Potential from the Forelimbs in Mouse Models of Motor Neuron Degeneration
Published on: June 15, 2018
Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model
Zenya Ito1, Shiro Imagama1, Kei Ando1
1Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Japan.
Study Design:
Animal study.
Purpose:
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.
Overview Of Literature:
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.
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