Thanks to electrodes, paralyzed people regain some control over their arms and hands.

What was once only a limited experiment could soon benefit more paraplegics in everyday life. About forty paralyzed people have regained partial control of their arms thanks to electrodes placed around their spinal cord. These results, detailed Monday in the journal Nature Medicine, demonstrate, according to the paper’s conclusions, the “safety and effectiveness” of the device, which consists of placing electrodes on the skin of paralyzed people around the site where their spinal cord was damaged. accident.

In total, about forty of these quadriplegics regained strength and use of their arms after two months of therapy using this device. This, promoted by the startup Onward, “could be a game changer for the majority of patients with spinal cord injury,” assured US researcher Chet Moritz, who led the study, during a press conference organized by Nature.

This research is part of an area in which significant advances have been made over the years. This involves allowing paraplegics to move again through electrical stimulation of their spinal cord. Some patients have already been able to walk again thanks to an implant placed directly into the spinal cord.

The seemingly less impressive results announced Monday could nonetheless be as life-changing or even more life-changing for some patients in the short term. “Everyone believes (…) that we just want to walk again,” explained British journalist Melanie Reed, paralyzed after falling from a horse some fifteen years ago, during the same press conference. “But for a paraplegic, the most important thing is to use your hands,” said a woman who, after using the device, can now scroll pages on her phone screen.

Its effect seems to last a long time

This system is also interesting from a practical point of view. This requires placing the box on the skin rather than surgically implanting the electrodes. An implant (a possibility Onward is also exploring) would likely be more effective, but also more difficult to use.

And to be useful, the box does not have to be installed constantly: it was tested during sessions of an hour each. Over time, its effect appears to persist as it helps develop new connections between the brain and the affected limbs. “The benefits increase over time, (even) when the stimulant is not working,” insisted Chet Moritz.

Above all, it is precisely because of its scale that this study marks a decisive step forward. Until now, research in this area has involved only a few isolated patients and has yielded impressive results, but not enough to conclude about the viability of such tools in everyday life. Here, the study was conducted worldwide on approximately sixty patients—an unprecedented sample. While not everyone made noticeable progress, nearly three-quarters benefited.

At this level, these results allow Onward to consider immediate negotiations with health authorities in countries such as the United States. “You can never predict when you will get approval,” explained researcher Grégoire Courtin, who led the study and is part of the Onward team. “But we think we can sell it by the end of the year in the US and then straight into Europe. »

In contrast, at the stage the study is at, it would take several more years to imagine that quadriplegics would regularly have access to implants that would allow them to walk again. A big unknown remains: price. “It’s not yet defined,” admits Grégoire Courtin, who promises that the goal is to remain “affordable.”