Paraplegics, paralyzed for years, have found sensations and partial control of their legs, even for some people a sex life, “unprecedented” results obtained thanks to innovative cerebral and physical rehabilitation.
“Until now, no one had observed the recovery of these functions in a patient for so many years (3 to 13 years) after a diagnosis of complete paralysis” of the lower limbs, says Dr. Miguel Nicolelis, specialist in neuroscience of the American Duke University (North Carolina) which led this study published in the journal Scientific Reports.
These “surprising” and “unprecedented” advances were obtained after a year with what is called a brain-machine interface (direct connection system between the brain and a computer), without any chip implantation, d ‘electrodes or stimulator in the body.
Each of the eight paralyzed patients of both legs must have imagined themselves walking with the help of a virtual avatar. What made it possible to reappear the representation of the lower limbs in his brain, noted the researchers who lead this project in Brazil.
The rehabilitation probably reactivated nerves of the spinal cord which had survived the trauma at the origin of the paraplegia (car accident, fall …).
“It may be a small number of residual nerve fibers, but sufficient to carry signals from the area of the motor cortex from the brain to the spinal cord,” says Dr. Nicolelis.
The rehabilitation combined an intensive immersion in virtual reality, reinforced by visual and tactile signals (giving the sensation of touching the ground) received by the patient and physical exercises, in particular on the treadmill. The material also includes exoskeletons, thought-supporting body support structures for walking.
A helmet of electrodes on the patient’s skull makes it possible to pick up the signals associated with the movements sent by the brain, in order to allow the computer software to decipher them.
Feel her baby
With this training, the patients were able to perform voluntary movements.
After a year, the sensations and muscular control of four patients had improved enough for the doctors to reclassify the level of their paralysis, from total to partial paraplegia. After twenty months, that number rose to seven, said the head of the study.
Most patients have also benefited from improved bladder control and bowel function, reducing their dependence on laxatives and catheters, and therefore the risk of infections, one of the leading causes of death among them.
The best results were seen in two women who had been paralyzed for more than ten years and had no sensation in the lower part of their body. A video shows one of them voluntarily moving her legs, supported by a kind of harness.
One of these patients can now sit and drive. One of them was also able, “for the first time, to smell her baby (her 2nd child) and the contractions” during her delivery, according to the researcher.
Male patients have also reported improved sexual performance. “Some of them have recovered the possibility of having sex, erections,” added Dr. Nicolelis.
Another study is planned to determine how long it would be desirable to continue this rehabilitation, even a light one.
Recently, a 24-year-old American quadriplegic, Ian Burkhart, had managed to use his hand to grab an object or have coffee, using software and a chip implanted in his brain to convert his thought into action. . This also involved bulky cables, unlike this new method.
This could be tested in the future on recently paralyzed patients. It could also benefit other pathologies (stroke, degenerative diseases), according to the researchers, who plan to reduce its cost to allow its dissemination.