Effect of repetitive transcranial magnetic stimulation on leg spasticity in primary progressive and secondary progressive form of multiple sclerosis

Abstract

Lower limb spasticity is one of the most common symptoms in multiple sclerosis (MS) patients with an increasing severity as the disease progresses. Previous clinical and experimental results of excitatory repetitive transcranial magnetic stimulation (rTMS) highlighted possible role in reducing of lower limb spasticity in MS patients. The aim of our pilot study was to explore effects of rTMS on leg spasticity in MS patients. Our pilot study included 20 MS patients with secondary progressive (SP) and primary progressive form (PP) of disease with Expanded Disability Status Scale (EDDS) score 4–6.5 and lower limb spasticity, that were referred to Clinic for Rehabilitation Dr Miroslav Zotovic, Belgrade. They were simple randomized in two groups: first group included ten patients with rTMS and second group was placebo group with sham rTMS. For rTMS intervention, we used the intermittent theta burst stimulation over M1 leg area for the worst affected leg. Both group had exercise therapy (ET) session after the rTMS (real/sham) intervention during the three weeks. Primary outcome measure for spasticity was Modified Ashworth Scale (MAS). Secondary outcome measures included clinical assessment of spasticity Multiple Sclerosis Spasticity Scale (MSSS88) and the Timed-25-foot walk. Outcome measures were evaluated before and after three weeks of treatment, and compared within the group and between two groups. There were no statistically differences between the group regarding age, gender, education, form and duration of disease, EDSS. A statistically significant difference was found in the group of patients treated with the rTMS for MAS (W = 2.714; P = 0.007), T25 W (Z = 2.813; P = 0.005) and MSSS88 (Z = 2.803; P = 0.005). In placebo group these changes were not statistically significant. rTMS associated with short period of ET may induce significant reduction of spasticity in SP and PP form of disease.