High-frequency repetitive transcranial magnetic stimulation and intermittent theta-burst stimulation for spasticity management in secondary progressive multiple sclerosis

Background and purpose The spasticity phenomenon is a significant factor in the development of disability. Repetitive transcranial magnetic stimulation (rTMS) is a promising treatment method for this disorder. Our aim was to compare the effects of two protocols of rTMS - the high-frequency (HF) rTMS (20 Hz) and the intermittent theta-burst stimulation (iTBS) - on the level of spasticity and concomitant symptoms in patients with secondary progressive multiple sclerosis with an analysis of the duration of the effects up to 12 weeks after the stimulation course. Methods Thirty-four patients with secondary progressive multiple sclerosis and lower spastic paraparesis were randomized into three groups: (i) HF-rTMS (20 Hz); (ii) iTBS; (iii) sham stimulation. Spasticity and spasticity-associated symptoms were assessed by the Modified Ashworth Scale, the Subjective Evaluating Spasticity Scale (SESS), the numerical analog scale, the Modified Fatigue Impact Scale and the pain level scale. Results The Modified Ashworth Scale was significantly reduced after the stimulation course in the HF-rTMS and iTBS groups. The SESS was reduced post-intervention and at the two follow-ups in the iTBS group, whilst HF-rTMS produced an SESS reduction only at the 2-week follow-up, with no effects in the sham group. Conversely, reduction in pain and fatigue was found in the HF-rTMS group. Conclusions The results show that HF-rTMS and iTBS significantly reduce spasticity measured by the Modified Ashworth Scale, in contrast to sham stimulation. Some evidence was found in favor of a longer-lasting effect of iTBS on the SESS and of a reduction in pain and fatigue after HF-rTMS.