GENEVA, Oct. 31 (Xinhua) -- Thanks to precise electrical stimulation of their spinal cords via a wireless implant, three patients with chronic paraplegia are able to walk over ground again and, with sufficient training, even without the stimulation, said a statement from Swiss Federal Institute of Technology Lausanne (EPFL) on Wednesday.
The three paraplegics sustained cervical spinal cord injuries many years ago and are now able to walk with the aid of crutches or a walker, thanks to a combination of targeted electrical stimulation of the lumbar spinal cord and weight-assisted therapy.
In the study called STIMO (STImulation Movement Overground), which is to be published in the latest issues of Nature and Nature Neuroscience, the team of researchers from EPFL, the University of Lausanne and the Lausanne University Hospital implanted an array of electrodes over the patients' spinal cords which allows to target individual muscle groups in the legs. Selected configurations of electrodes were then activating specific regions of the spinal cord, mimicking the signals that the brain would deliver to produce walking.
The challenge for the patients was to learn how to coordinate their brains' intention to walk with the targeted electrical stimulation, but that did not take long. All three study participants were able to walk with body-weight support after only one week of calibration, according to the researchers, and voluntary muscle control improved tremendously within five months of training.
The new rehabilitation protocols lead to improved neurological function by allowing the participants to actively train natural overground walking capabilities for extensive periods of time, as opposed to passive training like exoskeleton-assisted stepping.
The study achieves an unprecedented level of precision in electrically stimulating spinal cords, which the researchers said was "as precise as a Swiss watch." They are planning to use the findings to develop tailored neurotechnology to turn the rehabilitation paradigm into a treatment available at hospitals and clinics everywhere.