Ann Rehabil Med.  2017 Apr;41(2):211-217. 10.5535/arm.2017.41.2.211.

Relationship Between Motor Evoked Potential Response and the Severity of Paralysis in Spinal Cord Injury Patients

• Oh MK
• Kim HR
• Kim WS
• Shin HI

• KMID: 2389478
• DOI: http://doi.org/10.5535/arm.2017.41.2.211

Abstract

OBJECTIVE
To investigate the relationship between motor evoked potential (MEP) response and the severity of motor paralysis, evaluated according to the Korean disability evaluation system in patients with spinal cord injury (SCI).
METHODS
We analyzed 192 lower limbs of 96 SCI patients. Lower limbs were classified according to their motor scores, as determined by the International Standards for Neurological Classification of Spinal Cord Injury: motor score <10 (group 1); ≥10 and <15 (group 2); ≥15 and <20 (group 3); and ≥20 (group 4). MEP responses were classified as "˜normal', "˜delayed' or "˜absent', based on their onset latency, which was compared between the different motor score groups.
RESULTS
MEP responses and limb motor scores were highly correlated (p<0.001). There was a significant difference of MEP responses between the motor score groups (p<0.001). MEP response was markedly poorer in motor group 1 (limb motor score <10) than in the other three groups (p<0.0001). However, there were no differences between the three groups with motor scores of 10 or above.
CONCLUSION
Clinical utility of MEP as a complimentary tool to manual muscle tests could be limited to discriminating motor score groups with severe paralysis, i.e., single lower limb motor power grades of 0 or 1, and from grade 2, 3, and 4, or above, in the Korean disability evaluation system.

Keyword

Motor evoked potentials; Spinal cord injuries; Severity; Paralysis

MeSH Terms

Classification
Disability Evaluation
Evoked Potentials, Motor*
Extremities
Humans
Lower Extremity
Paralysis*
Spinal Cord Injuries*
Spinal Cord*

Figure

• 

  Fig. 1 Flow diagram of recruitment subjects. MEP, motor evoked potential; NLI, neurological levels of injury.

• 

  Fig. 2 Simple scatterplot of the correlation between motor response and motor score. MEP, motor evoked potential.

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