Abstract: Objective To explore the correlation between characteristics of surface electromyography (sEMG) from biceps brachii (BB)and triceps brachii (TB) and the Modified Ashworth Scale (MAS) during a passive movement of the spastic elbow in patients with hemiplegiaafter brain lesion. Methods 37 hemiplegics were assessed the elbow spasticity with MAS by a same therapist. Their sEMG of BB andTB were recorded synchronously. Results The Spearman analysis showed that the root mean square (RMS) of sEMG from BB (r=0.651),TB (r=0.912), TB+BB (r=0.905), TB-BB (r=0.903) correlated with MAS (P<0.001) when elbows were flexed, as well as elbows were extended(r=0.848, r=0.518, r=0.850, r=0.711, P<0.001). Conclusion sEMG can present the electrical activities of agonist and antagonist duringpassive movements of both elbow flexion and extension, which may help for the spasticity assessment.

Key words: surface electromyography, spasticity, elbow, Modified Ashworth Scale, passive movement