Stroke survivor moves hand for first time in nine years after spinal stimulation
A stroke survivor partially paralysed on her left side has been able to move her hand and arm for the first time in nine years following spinal cord stimulation.
Heather Rendulic, who had a stroke in 2012 when she was 22, was left with no mobility in her left hand as a result of chronic post-stroke muscle weakness.
Researchers from the University of Pittsburgh and Carnegie Mellon University in the US used their new technology to stimulate Ms Rendulic’s spinal cord in the neck area.
While being stimulated, Ms Rendulic – who lives in the US – was able to fully open and close her fist, lift and move a can of soup, and even use a fork and knife to cut a piece of steak – things she has not been able to do for nearly a decade.
Ms Rendulic said: “Stimulation feels kind of like a tickle and it’s never painful but it takes some getting used to, I would say.
“It’s just awesome because I can move my arm and hands in ways that I haven’t done in almost a decade.”
It is estimated around 100,000 people have strokes each year in the UK, with 1.2 million survivors.
Around two-thirds of working-age survivors are unable to return to their jobs, with long-lasting deficits in motor control playing a key role.
The researchers said the stimulation procedure does not require invasive surgery and involves implanting a pair of thin metal electrodes – resembling spaghetti strands – along the neck to engage nerve cells that are still intact.
Their findings have been published in the journal Nature Medicine.
Marco Capogrosso, assistant professor of neurological surgery at the University of Pittsburgh and co-senior study author, said: “We discovered that electrical stimulation of specific spinal cord regions enables patients to move their arm in ways that they are not able to do without the stimulation.”
He said Ms Rendulic was “able to move her hand and arm after nine years from day one” after receiving stimulation.
Prof Capogrosso added: “When she opened (her) hand after nine years (it) was a particularly intense moment, because obviously, she started crying and we all start to cry.
“The whole lab was crying because… we didn’t really expect that this could work as fast.”
The researchers said that the benefits of spinal cord stimulation have been shown to last for up to four weeks after the stimulation was stopped, with no serious side effects.
They believe their new technology may offer hope for people living with disabilities that would otherwise be considered permanent – because there are currently no effective treatments for paralysis in the chronic stage of stroke.
Co-senior author Douglas Weber, professor of mechanical engineering at the Neuroscience Institute at Carnegie Mellon University, said: “The sensory nerves from the arm and hand send signals to motor neurons in the spinal cord that control the muscles of the limb.
“By stimulating these sensory nerves, we can amplify the activity of muscles that have been weakened by stroke.
“Importantly, the patient retains full control of their movements: The stimulation is assistive and strengthens muscle activation only when patients are trying to move.”
As part of the next steps, the researchers are enrolling more trial participants to understand which stroke patients can benefit most from their technology.