A paraplegic can walk again thanks to a Lausanne implant. He can control movements with his thoughts. The research team published the evidence on Wednesday in the renowned journal “Nature”. The researchers from the Swiss Federal Institute of Technology Lausanne (EPFL) and the University Hospital of Lausanne (Chuv) implanted two different systems in the 40-year-old guinea pig.
➤ Read more: What happens with paraplegia?
➤ Read more: Paraplegia: the beginning of a second life
skullcap and spinal cord
On the one hand, two implants in the cranial vault, on the other hand, electrodes in the spinal cord. So far, Grégoire Courtine of the EPFL and his colleagues have tested the new implants on one patient: the Dutchman’s legs have been paralyzed since a bicycle accident twelve years ago. Thanks to the implants, he can now stand, walk and even climb stairs with a limited degree of independence with the help of a walker or crutches.
painted myself
“Last week, something had to be painted at home and there was no one who could help me. So I took the walker and did it myself. Standing up”, said the Dutchman in a presentation of the new study to the media. He can walk about 200 meters, then he gets tired. He can stand for two to three minutes without using his hands.
Furthermore, according to the study, neurorehabilitative support resulted in improved neurological recovery. The researchers observed improvements in their sensory perception and motor skills even when the digital connection was turned off.
According to the authors of the study, the implants in the spinal cord and the brain communicate through a kind of “digital bridge”. A spinal cord injury can interrupt communication between the brain and the area of the spinal cord that controls walking, leading to paralysis. The so-called Brain-Spine Interface (BSI) restores this communication.
Cranial implants measure brain activity with 64 electrodes. Based on this data, an artificial intelligence calculates the desired movement and translates it into stimulation commands, which are transmitted wirelessly to the 16-electrode electrode array in the spinal cord. The electrodes stimulate the so-called motor neurons and activate the muscles in a targeted way.
Control by thought possible
The Lausanne team developed the device in the spinal cord about five years ago and tested it on several patients. Until now, however, the command to walk had to be entered via a tablet. According to the authors of the study, controlling with thoughts makes movements more fluid and natural.
The BSI first had to be calibrated for this. Oskam was asked to visualize movements, such as the movement of a leg. The corresponding signals were measured with the electrodes in the brain. In this way, an artificial intelligence was trained to translate the brain signals into signals for the spinal cord electrodes. “We performed this calibration in a few minutes. It has worked reliably ever since,” study author Jocelyne Bloch of Chuv told the media.
“New Age”
“The concept of a digital bridge between the brain and spinal cord heralds a new era in the treatment of motor deficits due to neurological disorders,” the scientists wrote in the study. A similar strategy can also be used to restore arm and hand function in the future.
The Lausanne researchers now want to make BSI available worldwide as quickly as possible. According to a note from Chuv, they received support from the European Innovation Council (EIC) to develop a commercial version of the digital bridge.
However, independent researchers warn against false hope. “As always with such spectacular individual reports, it is not possible to conclude that there is a solution for other affected people,” said Winfried May of the Austrian Society for Biomedical Engineering at the Science Media Center. The symptoms of paraplegia in the case of spinal cord injury and therefore the prospects for restoring movement control with or without the use of technical aids are very different.
“Similar improvements will be possible for some patients, but not for many. In each individual case, the invasiveness, effort, and risks must always be weighed against the achievable benefit.”