Simultaneous stimulation in bilateral leg motor areas with intermittent theta burst stimulation to improve functional performance after stroke: a feasibility pilot study

BACKGROUND: Intermittent theta burst stimulation (iTBS) was widely used in stroke rehabilitation and was more efficient than repetitive transcranial magnetic stimulation in terms of inducing larger motor evoked potential and producing longer effects. To our knowledge, the outcomes are not available combining rehabilitation and iTBS for improving motor function of lower extremities in patients with stroke. AIM: To evaluate the feasibility and effectiveness of intermittent theta burst stimulation aiming to stimulate bilateral leg motor cortex and promote functional improvements. DESIGN: A single blind, randomized controlled pilot study. SETTING: Rehabilitation ward. POPULATION: Twenty patients with chronic stroke finally enrolled for analyzed. METHODS: Participants were randomized into two groups to receive 10 sessions of iTBS group and sham group over a 5-week period. The iTBS was delivered over the midline of skull to stimulate bilateral leg motor cortex. The outcome measures included balance, mobility, and leg motor functions were measured before and after interventions. RESULTS: Within-group differences were significant in the Berg Balance Scale for both groups (Z=-2.442, P=0.015 in iTBS group; Z=-2.094, P=0.036 in sham group), in the Fugl-Meyer Assessment (Z=-2.264, P=0.024) and Overall Stability Index of Biodex Balance System of iTBS group (Z=-2.124, P=0.034). However, no significant between-group differences were found. CONCLUSIONS: There was no powerful evidence to support the effectiveness of iTBS group better than sham control group. Some essential technical issues should be considered for future studies applying iTBS to stimulate bilateral leg motor cortex. CLINICAL REHABILITATION IMPACT: iTBS combined with stroke rehabilitation are probably expected to be useful to promote brain plasticity and functional performance but some technical issues should be carefully considered.