This is an experiment that holds many promises for the paraplegics. Three of them, treated with electric stimulation in Switzerland, have regained control of their muscles. They have been able to walk again, even without stimulation. This research of the École polytechnique fédérale de Lausanne (EPFL) and the university hospital of Lausanne (CHUV) is the subject of two articles appearing Wednesday respectively in Nature and Nature neuroscience.
previous u.s. studies published recently have shown an ability to take a few steps with walking aids, but only with continuous stimulation. “No one had demonstrated before” the ability to move or walk after the stopping of the stimulation in humans, provides to the Agency France-Presse Jocelyne Bloch (CHUV), who installed the implants (16 electrodes connected to a stimulator).
This is a “giant step forward” in research on injuries of the spinal cord, said a u.s. specialist from the university of Washington, Seattle, Chet Moritz, an editorial in the scientific journal Nature. The fact that after several months of stimulation, these three men were able to regain control of their paralyzed muscles, without activating the stimulation, is a ” solid proof that the brain and the spinal cord has restored the natural connections “, note-t-il. “Two of these participants were even able to walk (…) in using a walker with wheels for balance and safety,” he noted
The stimulation epidural electrodes are placed outside of the protective membrane of the spinal cord) at the lumbar level below the lesion has been used in combination with a physical training intensive with harness in these three injured marrow : David M. of Zurich (Switzerland), 28 years, paralysed after a sport accident in 2010 ; Gert-Jan Oskam, 35, of the netherlands, the victim of a bicycle accident in China in 2011, and Sebastian Tobler, 47 years old, from Fribourg (Switzerland), the more severely affected, of rugged mountain BIKING in 2013.
” after three to five months of training under stimulation appears some neurological recovery. The stimulation target the spinal level that controls the lower limb muscles are activated during walking. This stimulation facilitates the control of the brain, ” says Jocelyne Bloch. “The timing and the localization of the electric stimulation are essential for the ability of the patient to produce a voluntary movement “, according to the researcher Grégoire Courtine (EPFL).
The experiment consists of two phases : in the first, the stimulation allows the activation of the muscles and increases the endurance of the drive ; in a 2nd phase, we begin to see a neurological recovery, that is to say that some movements have become possible without stimulation, tells the story of the neurochirurgienne. The electrodes are connected by a cable to the neurostimulator housed in the abdomen, under the skin. A watch with a voice command allows the patient to activate the stimulator.
” The best is over 2 km, with stimulation in the laboratory after several months of training. It is currently still able to do it, ” says Jocelyne Bloch. These patients have gained in autonomy. “I should soon get to have a bbq myself standing,” said Gert-Jan, who can now travel short distances, even without stimulation.
David has regained muscle control of his left leg is completely paralyzed and has improved his right leg. If, for him, the wheelchair remains the way to travel the more effective it can already make a few steps without assistance. The more severely affected, Sebastian, needed an additional three months. Now, he can walk in the laboratory with the stimulus. He built a tricycle lying to a paraplegic who allows him, he says, ” (s)’go in the forest.”
Can they still progress ? “Certainly, but that requires relentless training,” says Jocelyne Bloch. The next step for the researchers will be to test this neurotechnology very soon after the trauma, when the neuromuscular system has not yet undergone atrophy due to paralysis chronic, ” ideally a few weeks (4-5) after the accident “, said the neurochirurgienne.
On the same subject A paraplegic walk again, thanks to an electrode in the spinal column