by Dennis Thompson
WEDNESDAY, May 24, 2023 (HealthDay News) — A Dutch man with paralyzed legs can now stand up and walk, thanks to a wireless brain-spine interface that responds to his thoughts by moving his legs.
Gert-Jan Oscum, 40, suffered a spinal injury from a bike accident in China 11 years ago that left him unable to walk.
Oscum now has a brain implant that picks up movement signals, which in a healthy person would travel to the spinal cord and move the legs. Instead, that implant transmits those signals wirelessly to another implant located in his lower spine, which then stimulates the leg muscles into action, the researchers report.
This experimental high-tech “digital bridge” between the brain and spinal cord allowed Oscum the other day to pick up a paint brush and do a simple low-tech chore around his home in the Netherlands.
“Something needed to be painted and there was no one to help me, so I had to walk around and paint,” Oscum said at a media briefing on Tuesday. “I did it myself, while I was standing.”
Researchers have been trying for years to restore patients’ ability to walk using nerve stimulators implanted in their spinal cords.
However, those test subjects often walked robotically and were unable to adapt their leg movements to different terrains.
Oscam benefits from the next step in that research, a means to allow the brain to control spinal cord stimulation and create more natural steps for patients.
“What we’ve been able to do here is to re-establish communication between the area of the brain and spinal cord that controls leg movement with a digital bridge that captures Gert-Jan’s thoughts and processes these thoughts.” translates into spinal cord stimulation to re-establish voluntary leg movement,” said senior researcher Grégoire Courtine, a neuroscientist and professor at the École Polytechnique Fédérale de Lausanne in France.
Oscum says it can now walk 100 to 200 meters (about 660 feet) in one go and can stand for two or three minutes without using its hands.
The device has also improved Oscam’s neurological recovery. He is able to walk with the help of crutches even after the implant is removed.
more natural movement
Due to his participation in the earlier studies, Oscum already had a spinal cord stimulator implanted. This allowed him to move, but his movements were robotic and stiff.
“It wasn’t entirely natural. The excitement was controlling me before, and now I’m controlling the excitement with my thoughts,” Oscum explained.
The researchers developed a passive implant placed over the motor center of their brains that could normally receive the signals that control movement.
Using a special headset and walker, Oscam can simulate more natural steps as the brain implant picks up movement signals and then transmits them to a spinal cord stimulator.
“We were able to calibrate the first model in just a few minutes, which enabled Gert-Jan to control the flexion of his hips. And after several minutes of training, he was able to walk naturally using the system.” was,” said lead researcher Henri Lorach, a professor at the Ecole Polytechnique Fédérale de Lausanne.
“We were able to decode not only simple movements, but movements of the hip, knee and ankle joints,” Lorach said. “And with this strategy, we actually gave the participant voluntary control of the spinal cord stimulation.”
Because Oscam can control so many parameters of leg movement — and receive feedback as it moves — it can walk on all kinds of different terrain, Courtine said. He can climb stairs, move up ramps, and stop and start as he pleases.
Brain-spine interfaces have also appeared to speed the recovery of the oscam. The researchers reported that after 40 sessions of neurorehabilitation, his ability to walk had improved significantly – he could move freely around his house, get in and out of the car, or walk with friends standing at the bar. Can drink.
“Now without stimulation, I can even walk,” said Oscum. “I think that says a lot. I’ve got enough strength and momentum to make the move.”
Courtine said it has previously been shown that spinal cord stimulation can trigger the growth of new neural connections.
“When the brain modulates the stimulus, there is even greater recovery because it is a convergence of digital connections with natural connections on the same type of neurons,” Courtine explained.
more research is needed
The new study was published May 24 in the journal Nature.
The research team hopes to recruit a second patient with lower body paralysis to receive the brain transplant, to see if the same system will work in others.
Marco Baptista, chief scientific officer for the Reeve Foundation, agreed that the technology needs to be tested in more people.
“This needs to be expanded and tested in other individuals who have different types of injuries,” Baptista said.
At the same time, Baptista said the effort represents the “next generation” of research in restoring movement through spinal cord stimulation.
“They’re moving more and more toward making the whole process more natural, where you’ve got the thought and the will to control the stimulus,” Baptista said.
Researchers are also starting another clinical trial that will help people with upper body paralysis.
“We’re really investigating how we can use the same principle to restore upper limb function by targeting the cervical spine cord with a similar technique,” Lorch said. “We can decode what the intention is to move the hand and arm and stimulate the motor pulse that will trigger this activity.”
Courteney said they want to make the technology even smaller, so it will be easier for people to participate in daily activities without wearing a hat or hanging up on devices.
“We can apply this to other disorders such as stroke, in which you can also record cortical activity and connect it to spinal cord stimulation to move the limb,” said co-researcher Dr. Jocelyn Bloch said, a neurosurgeon at Lausanne University Hospital. “You would think that this novel, pioneer therapy has many different applications.”
The University of California, San Diego has more information on spinal cord injuries and paralysis.
Source: Gert-Jan Oscum, 40, The Netherlands; Gregoire Courtine, PhD, neuroscientist and professor, École Polytechnique Fédérale de Lausanne, France; Henri Lorch, PhD, Professor, École Polytechnique Fédérale de Lausanne, France; Marco Baptista, PhD, Chief Scientific Officer, Reeve Foundation, Short Hills, NJ; Jocelyn Bloch, MD, neurosurgeon, Lausanne University Hospital, France; NatureMay 24, 2023