Background: Upper limb dysfunction is a frequent complication after stroke impairing outcome. Inhibitory repetitive transcranial magnetic stimulation (rTMS) applied over the contralesional hemisphere is supposed to enhance the positive effects of conventional rehabilitative treatment.
Objective: This double-blind randomized placebo-controlled trial investigated whether inhibitory rTMS as add-on to standard therapy improves upper limb spasticity.
Methods: Twenty-eight patients (aged 44 to 80 years) with unilateral stroke in the middle cerebral artery territory were analyzed. Participants were randomly assigned to inhibitory, low-frequency (LF-) rTMS (n = 14) or sham-rTMS (n = 14). The primary outcome measure was the spasticity grade, which was assessed with the Modified Ashworth Scale (MAS). In addition, the Fugl-Meyer-Assessment (FMA) for the upper extremity (UE) and a resting-state fMRI were performed to measure motor functions and the sensorimotor network, respectively.
Results: The MAS score was reduced in the LF-rTMS group only, whereas the FMA score improved in both groups over time. Regarding the fMRI data, both groups activated typical regions of the sensorimotor network. In the LF-rTMS group, however, connectivity to the left angular gyrus increased after treatment.
Conclusion: Changes in functional connectivity in patients receiving inhibitory rTMS over the contralesional motor cortex suggest that processes of neuronal plasticity are stimulated.
Keywords: Stroke; neurological rehabilitation; rTMS; repetitive transcranial magnetic stimulation; resting-state functional connectivity; spasticity; upper limb paresis.