Reduction of spasticity with repetitive transcranial magnetic stimulation in patients with spinal cord injury

Abstract

Objective: Spasticity with increased tone and spasms is frequent in patients after spinal cord injury (SCI). Damage to descending corticospinal pathways that normally exert spinal segmental control is thought to play an important causal role in spasticity. The authors examined whether the modulation of excitability of the primary motor cortex with high-frequency repetitive transcranial magnetic stimulation (rTMS) could modify lower limb spasticity in patients with incomplete SCI.

Methods: Patients were assessed by the Modified Ashworth Scale, Visual Analogue Scale, and the Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) and neurophysiologically with measures of corticospinal and segmental excitability by the H(max)/M(max), T reflex, and withdrawal reflex. Fifteen patients received 5 days of daily sessions of active (n = 14) or sham (n = 7) rTMS to the leg motor area (20 trains of 40 pulses at 20 Hz and an intensity of 90% of resting motor threshold for the biceps brachii muscle).

Result: A significant clinical improvement in lower limb spasticity was observed in patients following active rTMS but not after sham stimulation.This improvement lasted for at least 1 week following the intervention. Neurophysiological studies did not change.

Conclusions: High-frequency rTMS over the leg motor area can improve aspects of spasticity in patients with incomplete SCI.

Conflict of interest statement

Declaration of Conflicting Interests

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Figures

Figure 1

Visual analogue scale Note: Patients with active stimulation reported significant improvement in spasticity after the last session and 1 week follow-up when compared with the baseline condition measured by the visual analogue scale. *P < .005 (Wilcoxon test).

Figure 2

Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) results Note: Patients with active stimulation reported significant improvement in spasticity after last session and 1 week follow-up when compared with the baseline condition measured by the SCI-SET. *P = .006 (Wilcoxon test).