Effects of Transcutaneous Spinal Direct Current Stimulation in Incomplete Spinal Cord Injury

The purpose of the study is to investigate the effects of a novel therapeutic approach to promote functional recovery and spasticity in chronic SCI. The tsDCS effect on neuro-physiological measures such as H reflex and somatosensory evoked potential (SSEP) wiil be evaluated in subjects with SCI. This incremental, design will allow the establishment of strong electrophysiological data prior to rapid clinical translation of the findings about this promising, early-stage technique.

The central hypothesis is twofold: 1) active tsDCS will lead to a change in Hmax/M max ratio than sham tsDCS, in a polarity dependent manner; and 2) active tsDCS will lead to a change in SSEP amplitude and latency, in a polarity dependent manner.

Inclusion criteria

• Providing written informed consent prior to any study related procedures
• 18-65 years of age
• Motor incomplete SCI classified as B, C or D by the American Spinal Injury Association Impairment Scale (AIS)
• Traumatic lesion at or above T8-T9 neurological level
• Body mass index ≤ 30 (in order to facilitate reliable location of body landmarks guiding stimulation);
• Chronic SCI (time since injury>6 months)

Exclusion criteria

• Unstable cardiopulmonary conditions
• History of seizure, head injury with loss of consciousness, severe alcohol or drug abuse, and/or psychiatric illness
• Any joint contracture or severe spasticity, as measured by a Modified Ashworth Score 4
• Subject who cannot provide self-transportation to the study location
• Cardiac or neural pacemakers
• Pregnancy
• lower motor neuron injury (eg: peripheral neuropathy, cauda equina syndrome)
• Uncontrolled diabetes with HbA1C>7
• History of severe autonomic dysreflexia
• No planned alteration in therapy or medication for muscle tone during the course of the study(No botulinum toxin injections in last 3 months, No phenol injections in last 6 months, intrathecal baclofen pump dose stable for past 3 months, etc)
• Conditions for e.g., severe arthritis, extreme shoulder pain that would interfere with valid administration of the measures or with interpreting motor testing;
• No contraindications to tsDCS
• ferromagnetic material in the brain or in the spine (except for titanium used in segmental)