Scientists at the University of California, LA used non-invasive spinal cord stimulation to give a completely paralyzed man the ability to step out in a bionic device.
Breakthrough for paralysis patients
Mark Pollock, a 39 year-old man who was paralyzed from the waist down for four years prior to the study, was able to voluntarily control a robotic exoskeleton to take a few thousand steps. This is the first time that a person with paralysis was able to control his or her muscles and work in tandem with a robotic device to move in a rhythmic fashion. The scientists also used non-invasive electrical stimulation of the spinal cord to assist the process. Pollock was trained on the bionic exoskeleton for five days before the spinal cord stimulation, which proceeded for two weeks at selected sites along the vertebral column.
How does the robotic exoskeleton work?
Manufactured by a California-based company, Ekso Bionics, the exoskeleton is a battery-powered wearable suit that enables step-like movements with the help of the spinal cord stimulation. It captures data related to stepping work carried out by the device, versus muscle movements initiated by the patient alone. This is an important metric because if the robot does all the work, the patient becomes passive and the nervous system refuses to push any further and shuts down.
In Pollock’s case, the researchers noticed that he was able to flex and raise his legs during and after the electrical stimulation, which is a sign that he is able to control the actions of the robot with his muscles. The spinal cord stimulation technique doesn’t require surgery and helps initiate leg movements by conveying nerve signals to the cord.
Assisted walking from Robotic Exoskeleton provides hope for paraplegics
The researchers found that external stimulation significantly improved Pollock’s control of the exoskeleton. They believe that both the robotic exoskeleton and the stimulation work synergistically to offer better volitional control of movements. Moreover, the combination also greatly improved his cardiovascular function and muscle tone.
He achieved a heart rate of 138 beats per minute, which, being in the aerobic zone, is impressive. This achievement was not only exhilarating but also emotional considering that Pollock was an athlete before the accident in 2010 that injured his spinal cord and rendered him paraplegic. This invention provides 6 million Americans who live with paralysis hope of a life with improved mobility and control, albeit with assistance.
Featured Image courtesy of Ekso Bionics via Flickr.
Image courtesy of Mark Pollock.
