Paralyzed patients take steps with implants
WASHINGTON — Three people whose legs were paralyzed for years can stand and take steps again thanks to an electrical implant and months of intense rehab, researchers reported Monday.
The milestone, reported by two teams of scientists working separately, isn’t a cure. The patients walk only with assistance — holding onto a rolling walker or with other help to keep their balance. Switch off the spinal stimulator and they no longer can voluntarily move their legs.
But during one physical therapy session at the Mayo Clinic, 29-year-old Jered Chinnock moved back and forth enough to cover the equivalent of the length of a football field.
“The walking side of it isn’t something where I just leave my wheelchair behind and away I go,” Chinnock, of Tomah, Wisconsin, said. But “there is the hopeful side of, maybe I’ll gain that — where I can leave the wheelchair behind, even if it is to walk to the refrigerator.”
The work is part of a quest to help people with spinal cord injuries regain function, and specialists say while it’s been attempted in only a Jered Chinnock, center, stands with help from his therapy team at the Mayo Clinic in Rochester, Minn. Chinnock, paralyzed since 2013, can stand and take steps on his own thanks to an electrical implant and months of intense rehab. Helping Chinnock are, from left, Margaux Linde, Megan Gill, Daniel Veith and Jonathan Calvert.
few people, it’s a promising approach that needs more study.
With the new approach, the three patients are taking steps under their own power — “intentionally moving,” according to the reports published Monday in Nature Medicine and the New England Journal of Medicine.
How does it work? One theory: Circuits of nerves below the injury site are dormant but still living.
Applying electrical current, in customized patterns, could wake up some of those circuits and, with rigorous rehab to revive rusty connections, eventually enable them to receive simple commands.
“Recovery can happen if you have the right circumstances,” said University of Louisville professor Susan Harkema, who co-authored the New England Journal study.
“This study gives hope to people who are faced with paralysis that functional control may be possible,” said Dr. Kendall Lee, a Mayo neurosurgeon who treated Chinnock and co-authored the Nature Medicine report.
Four years ago, Harkema’s team made headlines when a few patients implanted with spinal stimulators — originally developed to treat pain — were able to wiggle their toes, move their legs and briefly stand.
Lee and Kristin Zhao, who directs Mayo’s assistive and restorative laboratory, decided to repeat the experiment — and Chinnock’s success was the result.
He’d been paralyzed in a 2013 snowmobile accident, with no movement or sensation below his midback. He underwent 43 weeks of intense physical therapy and stimulator adjustments. At first, trainers positioned his knees and hips to help him stand and shift his weight on a treadmill. Eventually, he learned to move his legs and propel himself forward with a walker.
Meanwhile in Louisville, Harkema’s team was working with two more paralyzed volunteers eager to test the approach. In one session in the lab, Jeff Marquis, 35, of Louisville made it almost the length of a football field without stopping for a rest.
Kelly Thomas, 23, of Lecanto, Florida, recalled, “One day we were walking and they were helping me as usual and then they stopped helping me and I took maybe three or four steps in sequence. My eyes got teary and I was like, ‘Oh my god, that just happened, I just took steps.’”