A sham-controlled, phase II trial of transcranial direct current stimulation for the treatment of central pain in traumatic spinal cord injury

Abstract

Past evidence has shown that motor cortical stimulation with invasive and non-invasive brain stimulation is effective to relieve central pain. Here we aimed to study the effects of another, very safe technique of non-invasive brain stimulation--transcranial direct current stimulation (tDCS)--on pain control in patients with central pain due to traumatic spinal cord injury. Patients were randomized to receive sham or active motor tDCS (2mA, 20 min for 5 consecutive days). A blinded evaluator rated the pain using the visual analogue scale for pain, Clinician Global Impression and Patient Global Assessment. Safety was assessed with a neuropsychological battery and confounders with the evaluation of depression and anxiety changes. There was a significant pain improvement after active anodal stimulation of the motor cortex, but not after sham stimulation. These results were not confounded by depression or anxiety changes. Furthermore, cognitive performance was not significantly changed throughout the trial in both treatment groups. The results of our study suggest that this new approach of cortical stimulation can be effective to control pain in patients with spinal cord lesion. We discuss potential mechanisms for pain amelioration after tDCS, such as a secondary modulation of thalamic nuclei activity.

Delayed pain decrease following M1 tDCS in spinal cord injury: A randomized controlled clinical trial

“…However, the precise mechanisms leading to central sensitization in SCI are not yet understood. It is known that increased spinal cord excitability leads to enhanced activity in pain-related brain structures, including the sensorimotor cortex [7]. The development of central sensitization is one of the reasons that could explain why standard treatments for chronic pain in SCI are not effective in alleviating pain since they do not target the modulation of pain-related dysfunctional brain areas.…”

A different type of procedure for a different type of pain

“…In a separate study, these investigators also observed that tDCS had analgesic properties for the central pain of spinal cord injury (18). A similar treatment, transcranial magnetic stimulation (TMS), has been more widely studied and used to stimulate neural regions noninvasively and has analgesic properties in both healthy individuals and patients with chronic pain (19).…”

La stimulation transcrânienne à courant continu : un nouvel outil de neurostimulation

“…Des é tudes ont mis en é vidence une diminution des symptô mes dé pressifs selon les scores obtenus à l'Hamilton Depression Rating Scale, la Beck Depression Inventory (Fregni et al, 2006a) . Les auteurs ont noté une diminution similaire des symptô mes dé pressifs suite au traitement pharmacologique et aux stimulations cé ré brales.…”

“…Fregni et al (2006a) ont é tudié les effets de la tDCS sur M1 ainsi que sur le cortex pré frontal dorsolaté ral. La tDCS anodique a induit une amé lioration de la fonction motrice alors que les stimulations cathodiques de M1 et anodique et cathodique du cortex PFDL n'ont montré aucun effet sur la motricité des patients.…”