Gert-Jan Oskam, 40, from the Netherlands, suffered a spinal cord injury at neck level after a serious bicycle accident in 2011 that left him immobilized from the waist down and his arms partially paralyzed with no possibility of improvement. At that time, being able to scratch your nose was a triumph.
But now, thanks to an international team of scientists, artificial intelligence, and numerous rehabilitation sessions, he has been able to walk again with the assistance of a wireless digital bridge that restores communication between the brain and nerves under his spinal cord injury. which has allowed him to re-establish control over his limbs.
This interface has allowed him to regain control over movement and has allowed him to stand up, walk and even climb stairs, as explained by the scientists in an article published in the journal Nature that describes this scientific milestone.
The device, called brain-spine interfacebuilds on previous work by Grgoire Courtine, a neuroscientist at the Swiss Federal Institute of Technology in Lausanne, Switzerland, who demonstrated as early as 2018 that this technology, combined with intense training, stimulates the lower spine using electrical impulses and can help to people with spinal cord injuries to walk again.
The researchers, coordinated by Henry Lorach, Andrea Galvez and Valeria Spagnolo, from the University of Lausanne, have reported remarkable improvements in their sensory perceptions and motor skills, even when the digital bridge was turned off.
Two wireless implants and a lot of rehabilitation work
A spinal cord injury disrupts communication between the brain and the region of the spinal cord that produces walking, leading to paralysis. The researchers restored this communication with a digital bridge between the brain and spinal cord that “allowed a person with chronic quadriplegia to stand and walk naturally,” they explain in the study.
The artifact consists of two wireless electronic implants: one in the brain that decodes the electrical signals that the brain generates when it “sends” the order to walk to the legs, and a neurostimulator connected to an electrode array on the region of the spinal cord that controls the movement of the legs . all this is translated into an autonomous sequence of electrical stimulation of the spinal cord.
This brain-spine interface (BSI) consists of fully implanted pacing and recording systems that establish a direct link between cortical signals and analog modulation of epidural electrical stimulation directed at regions of the spinal cord involved in gait production,” they further explain in the study. .
“Thanks to algorithms based on adaptive artificial intelligence methodsmovement intentions are decoded in real time from brain recordings,” explains one of the project scientists, Guillaume Charvet, from the University of Grenoble Alpes. Once implanted rehabilitation has been essentialwhich together with the device has managed to develop new nerve connections”.
New life for Oskam
after a few 40 intense rehabilitation sessions Using the brain-spine interface, Oskam regained the ability to voluntarily move his legs and feet. That kind of voluntary movement was not possible only after spinal stimulation, and it suggests that training sessions with the new device contributed to better recovery in nerve cells that were not completely severed during their injury. Oskam can also walk short distances without the device on crutches.
The patient joined this clinical trial in 2017. He first had the electrodes surgically inserted into his lower back, the following months were spent in the hospital stretching, standing and walking, first with a harness and then with a sling. crutches. He managed to take a few steps without the help of any device, but after three years, he was stuck and accepted the proposal to try this new digital bridge. He thus combines the spinal implant with two new disc-shaped implants inserted into his skull so that two grids of 64 electrodes rest against the membrane covering the brain.
The implant has been life-changing, says Oskam. “Last week I needed to paint something and there was no one at the time who could help me. So I got on the walker and I got the paint and i could do it myself while I was standing up,” he recounts in Nature.
When Oskam thinks about walking, the skull implants detect electrical activity in the cortex, the outer layer of the brain. This signal is wirelessly transmitted and decoded by a computer Oskam wears in a backpack, which then transmits the information to the spinal pulse generator.
The previous device, “was more of a pre-programmed stimulation” that generated robotic stepping movements, Courtine says. “Now it’s completely different, because Gert-Jan has full control over the stimulation parameter, which means she can stop, walk or climb stairs.”
“The BSI allows natural control over the movements of their legs to stand, walk, climb stairs and even negotiate rough terrain. This, in addition to the fact that neurorehabilitation improved neurological recovery, has allowed the patient to walk with crutches on the ground even when the BSI was turned off. This digital bridge establishes a framework for restoring natural movement control after paralysis,” the researchers note.
Now Oskam can walk better, avoid obstacles and climb stairs: “Before the stimulation controlled me, now I am the one who controls the stimulation.” Thanks to this complex device, he has recovered a lot of mobility and, in addition, power share a beer at a bar with his friends: “A small pleasure that represents a significant change in my life.”
Great news for spinal cord injuries
Bruce Harland, a neuroscientist at the University of Auckland in New Zealand, notes that this continued improvement in spinal function is great news for anyone with a spinal cord injury, “because even if it’s a long-term chronic injury , there are still a few ways that healing could occur.”
So far, the digital bridge has only been tested on one person. In the future, according to the researchers, a similar strategy to restore arm and hand function. Likewise, they believe that this digital bridge could also be applied to other clinical indications, such as paralysis due to stroke. Courtine’s team is currently recruiting three more people to see if a similar device can restore arm movements.
The company responsible for the digital bridge, ONWARD Medical, together with the Swiss universities responsible for the study, has received support from the European Commission to develop a commercial version of the digital bridge, with the aim of making the technology available worldwide.
“It’s certainly a big leap” towards improved function for people with spinal cord injuries, says neuroscientist Anna Leonard of the University of Adelaide in Australia. There is still room for other interventions, such as stem cellsto further improve the results.
Antonio Lauto, a biomedical engineer at the University of Western Sydney, Australia, adds that it is also necessary to design less invasive devices, as one of Oskam’s skull implants had to be removed after about five months due to an infection. But Jocelyne Bloch, the neurosurgeon at the Swiss Federal Institute of Technology who implanted the device, says the risks are minimal compared to the benefits: “it’s worth the risk.”