Correlation of N30 somatosensory evoked potentials with spasticity and neurological function after stroke: A cross-sectional study


  • Lilin Chen Department of Rehabilitation Medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
  • Weijie Li
  • Shimei Cheng
  • Shouyi Liang
  • Mudan Huang
  • Tingting Lei
  • Xiquan Hu
  • Zhenhong Liang
  • Haiqing Zheng



stroke, hemiparesis, spasticity, N30 somatosensory evoked potential, motor evoked potential, function recovery


Objective: To test whether the presence of N30 somatosensory evoked potentials, generated from the supplementary motor area and premotor cortex, correlate with post-stroke spasticity, motor deficits, or motor recovery stage.

Design: A cross-sectional study.

Patients: A total of 43 patients with stroke hospitalized at Maoming People’s Hospital, Maoming, China.

Methods: Forty-three stroke patients underwent neurofunctional tests, including Modified Ashworth Scale (MAS), Brunnstrom stage, manual muscle test and neurophysiological tests, including N30 somatosensory evoked potentials, N20 somatosensory evoked potentials, motor evoked potentials, H-reflex. The results were compared between groups. Correlation and regression analyses were performed as well.

Results: Patients with absence of N30 somatosensory evoked potential exhibited stronger flexor carpi radialis muscle spasticity (r = –0.50, p < 0.05) and worse motor function (r = 0.57, p < 0.05) than patients with presence of N30 somatosensory evoked potential. The generalized linear model (GLM) including both N30 somatosensory evoked potentials and motor evoked potentials (Akaike Information Criterion (AIC) = 121.99) better reflected the recovery stage of the affected proximal upper limb than the models including N30 somatosensory evoked potentials (AIC = 125.06) or motor evoked potentials alone (AIC = 127.45).

Conclusion: N30 somatosensory evoked potential status correlates with the degrees of spasticity and motor function of stroke patients. The results showed that N30 somatosensory evoked potentials hold promise as a biomarker for the development of spasticity and the recovery of proximal limbs.

Lay abstract

Impair motor function and spasticity adversely affect the ability to conduct the activities of daily life. Somatosensory evoked potentials and motor evoked potentials are essential to differential evaluation of degree of post-stroke spasticity and stage of motor recovery. This is the first study of the correlations between somatosensory evoked potentials N30, components of somatosensory evoked potentials related to the supplementary motor area and dorsolateral premotor cortex combined with motor evoked potentials and motor function. The results indicate that the N30 somatosensory evoked potential status is correlated with the degrees of spasticity and motor function of stroke patients. The conclusion showed that N30 Somatosensory evoked potentials hold promise as a biomarker for the development of spasticity and the recovery of proximal limbs


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How to Cite

Chen, L., Li, W., Cheng, S., Liang, S., Huang, M., Lei, T., Hu, X., Liang, Z., & Zheng, H. (2021). Correlation of N30 somatosensory evoked potentials with spasticity and neurological function after stroke: A cross-sectional study. Journal of Rehabilitation Medicine, 53(9 (September), jrm00223.



Original Report