Eight patients paralyzed from spinal cord injuries regained partial muscle control and sensation in their lower limbs after training with brain-controlled robotics, according to a study published in Scientific Reports.
The research was led by Duke University neuroscientist Miguel Nicolelis, PhD, as part of the Walk Again Project in São Paulo and included five participants who were paralyzed for at least 5 years and two participants who were paralyzed for more than a decade, according to a university press release. The patients spent at least 2 hours a week using brain-machine interfaces, including a virtual reality system that used their brain activity to simulate full control of their legs. The interface was a fitted cap lined with 11 noninvasive electrodes that recorded brain activity through electroencephalogram signals. During most of their training, the patients also wore a sleeve equipped with haptic feedback to enrich the experience, the release noted. As they progressed, patients graduated from virtual reality to equipment that required more control over their posture, balance and ability to use their upper limbs. This included two commercially available walking devices that used overhead harnesses to support weight as the user built up strength.
Following 7 months of training, several patients saw significant changes. After a year, four patients’ sensation and muscle control changed enough that doctors upgraded their diagnoses from complete to partial paralysis, according to the release. Most patients saw improvements in their bladder control and bowel function, which reduced their reliance on laxatives and catheters. These changes also reduced their risk of infection.
One participant, a 32-year-old woman paralyzed for 13 years, was unable to stand using braces at the time of the trial. During the course of the study, she was able to walk using a walker, braces and a therapist’s help, according to the study. At 13 months, she was able to move her legs voluntarily while her body weight was supported in a harness.
“We could not have predicted this surprising clinical outcome when we began the project,” Nicolelis, who is also co-director of the Duke Center for Neuroengineering, said in the release. “What we are showing in this paper is that patients who used a brain-machine interface for a long period of time experienced improvements in motor behavior, tactile sensations and visceral functions below the level of the spinal cord injury,” he said. “Until now, nobody has seen recovery of these functions in a patient so many years after being diagnosed with complete paralysis.”
Researchers hypothesize that the weekly training allowed the patients to re-engage spinal cord nerves that survived the impact of the car crashes, falls and other trauma that paralyzed their lower limbs. Nearly all of the patients have continued their rehabilitation, which now exceeds 2 years of training, the study noted.
According to the release, the researchers plan to publish additional data about patients’ continued progress. They also plan to create a new trial with patients who suffered more recent spinal cord injuries to determine if quicker treatment can lead to more efficient results.
The study was funded by grants from the Brazilian Financing Agency for Studies and Projects, Brazilian Ministry of Science, Technology and Innovation, and the Itaú Bank.
Nicolelis M. Sci Rep. 2016;doi:10.1038/srep30383.
Disclosure: Nicolelis reports no relevant financial disclosures.