[Effect of electroacupuncture in different frequencies on electromyography and ambulation in stroke patients with lower-extremity spasticity: a randomized controlled study].

OBJECTIVE: To assess the effect of electroacupuncture in different frequencies by electromyography and walking function measure in post-stroke patients with lower-extremity (OLE) spasticity and hemiparesis. METHODS: Fifty cases of post-stroke whose motor deficit was classified into Brunnstrom stage II - IV were randomly divided into a 100 Hz group, a 50 Hz group and a 2 Hz group. They were accepted 100 Hz, 50 Hz or 2 Hz of electroacupuncture (EA) therapy combined with standard rehabilitation program. Main outcome measures included integrated electromyography (IEMG) score during maximum isometric voluntary contraction (MIVC) of the knee flexors and extensors, ankle dorsiflexors and planterflexors in the affected LE recorded by surface EMG, Co-contraction ratio calculated by IEMG score of the antagonist over that of the agonist plus antagonist, Composite Spasticity Scale (CSS), Fugl-Meyer Motor Scale (FMS) and Functional Ambulation Categories (FAC) on LE. All outcomes were assessed at the baseline and after treatment by the professional practitioners who blinded to the treatment. RESULTS: After EA treatment, IEMG of rectus femoris were decreased in 100 Hz and 50 Hz groups (P < 0.01, P < 0.05), and better than that in 2 Hz group (both P < 0.05); gastrocnemius IEMG were decreased in 100 Hz and 50 Hz groups (P < 0.05, P < 0.01); but IEMG of tibialis anterior muscle was increased only in 50 Hz group (P < 0.05). During knee flexion, EMG co-contraction ratio in MIVC declined in 100 Hz and 50 Hz groups were decreased significantly (P < 0.05, P < 0.01), and the co-contraction ratio between the non-affected and affected side were increased significantly in all the 3 groups after treatment (P < 0.01, P < 0.05). During ankle dorsiflexion, co-contraction ratio were decreased significantly in all the 3 groups (P < 0.05, P < 0.01), and cocontraction ratio between the non-affected and affected side was increased significantly only in 100 Hz after treatment (P < 0.01). FMS score, CSS and FAC were improved in all the 3 groups after treatment (all P < 0.01), but only FAC in 100 Hz group showed better effect than that in 50 Hz group or 2 Hz group (both P < 0.05). CONCLUSION: Electroacupuncture therapy combined with rehabilitation program is effective for the spasticity status of lower-extremity in post-stroke. The therapeutic effect of EA in the frequencies of 100 Hz or 50 Hz is superior to that of 2 Hz stimulation and parameter of 100 Hz may be optimal.