Transcranial direct current stimulation for spasticity in patients with multiple sclerosis: Exploring novel routes

Patients with Multiple sclerosis (MS) usually suffer from severe neurological disabilities. Spasticity is one of the most bothering and disabling manifestations that MS patients suffer from. Owing to being a chronic inflammatory demyelinating disorder; finding new modalities to alleviate some of the disabilities related to MS became a desired objective. Transcranial direct current stimulation (tDCS), a relatively new tool for modulating cortical excitability has been recently considered as a tool to provide symptomatic treatment for many neurologic and psychiatric diseases. In our study, we used tDCS to assess its effect on spasticity in MS patients.

5 consecutive daily sessions of 20 minutes duration of active anodal tDCS over the ipsilesional motor cortex were given to 10 relapsing remitting MS (RRMS) patients with at least 1 spastic lower limb (active group) who were compared with other matched10 RRMS patients who received sham stimulation (sham group). The outcome was to measure the effect on spasticity both clinically using the Modified Ashworth Scale (MAS) and through neurophysiological assessment (H reflex latency and H/M amplitude ratio).

Patients who received active anodal tDCS showed significant improvement (p< 0.05) in the H/M amplitude ratio as compared to the sham group. However, there was no significant difference between the two groups in the MAS. H latency showed significant stability in active group when compared to the sham group.

Anodal direct current stimulation of the ipsilesional motor cortex in patients with MS, resulted in reduced spasticity as per neurophysiological assessment.