An investigational, non-invasive medical device shows promise as a possible treatment for spasticity in patients who have experienced a stroke, Feinstein Institutes for Medical Research scientists report.

Their study, published in Springer Nature’s Bioelectronic Medicine, suggests that trans-spinal direct current stimulation and peripheral nerve direct current stimulation significantly reduced upper limb spasticity in participants who experienced a stroke.

Spasticity is a residual inability of the brain to control muscle tone. It increases muscle stiffness, which inhibits movement of the hands, arms, and legs; can affect the face and throat; and sometimes causes pain.

Efforts to treat upper limb spasticity have focused on intensive, repetitive, activity-dependent learning; however, it is common to experience residual spasticity despite aggressive therapy. When spasticity continues to worsen and causes pain, the standard-of-care is botox (botulinum toxin) injection, according to a media release from Feinstein Institutes for Medical Research.

“Spasticity is a persistent and common inhibitor of movement in patients with chronic stroke, and it has been a great hurdle as we continue to use intensive training to assist motor recovery,” says Bruce T. Volpe, MD, professor at the Feinstein Institutes and lead author of the paper, in the release.

“The surprise in these clinical results were the improved motor functions that apparently occurred with the focused treatment only of spasticity. We are eager to start a trial that couples motor training and anti-spasticity treatment.”

The treatment involves passing a direct electrical current across the spinal cord with a skin surface electrode, known as trans-spinal direct current stimulation (tsDCS), and adding a peripheral direct current stimulation (pDCS) in the paralyzed upper limb. There are additional benefits to patients when tsDCS is combined with pDCS.

Volpe, along with a team that includes Johanna Chang, MS, Alexandra Paget-Blanc, BS, and Maira Saul, MD, employed this device in patients with chronic stroke and hemiparesis to test whether treatment would decrease upper limb spasticity. The trial was a single-blind cross-over design study.

Twenty six participants were treated with five consecutive days of 20 minutes of active, paired tsDCS+pDCS. The participants received both active and sham stimulation conditions, but were not told the order of stimulation.

The device used in the trial was PathMaker Neurosystems Inc’s MyoRegulator, a non-invasive device designed to provide simultaneous, non-invasive stimulation intended to suppress hyperexcitable spinal neurons involved with spasticity.

The results demonstrated that the active treatment condition significantly reduced upper limb spasticity for up to five?weeks and these patient responders saw significant improvements in motor function, the release explains.

[Source(s): Feinstein Institutes for Medical Research, PR Newswire]