Differentiating Neurodegenerative Disease From Compressive Cervical Myelopathy Using Motor-Evoked Potentials
Naosuke Kamei1, Toshio Nakamae1, Toshiaki Maruyama1
1Department of Orthopedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Spine
|April 11, 2023
Summary
Motor-evoked potentials (MEPs) can help distinguish amyotrophic lateral sclerosis (ALS) from compressive cervical myelopathy (CCM). Specific MEP amplitude and F wave frequency differences were identified, aiding in diagnosis.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Differentiating compressive cervical myelopathy (CCM) from neurodegenerative diseases is crucial for surgical planning.
- Motor-evoked potentials (MEPs) offer a potential diagnostic tool.
Purpose of the Study:
- To evaluate the utility of MEPs in distinguishing CCM from neurodegenerative conditions, specifically amyotrophic lateral sclerosis (ALS) and demyelinating diseases.
- To identify specific MEP parameters that differentiate CCM from ALS.
Main Methods:
- A retrospective case-control study involving healthy volunteers, CCM patients, ALS patients, and patients with demyelinating diseases.
- MEPs were recorded from abductor digiti minimi (ADM) and abductor hallucis (AH) muscles.
- Analysis included central motor conduction time, peripheral conduction time, MEP amplitude, and F wave frequency, with ROC analysis for CCM vs. ALS differentiation.
Main Results:
- Significant differences in MEP amplitude and F wave frequency were found between CCM and ALS.
- MEP amplitude of AH (cutoff 11.2 mV) showed high accuracy (87.5% sensitivity, 85.7% specificity) in differentiating CCM from ALS.
- Reduced F wave frequency was observed in all ALS patients but not in controls or other disease groups.
Conclusions:
- MEP amplitude and F wave frequency are valuable in differentiating ALS from CCM.
- These neurophysiological measures can aid in clinical diagnosis and treatment decisions for spinal cord compression.
