A completely paralysed man has been able to regain the ability to walk with the help of a robotic exoskeleton, the first experiment of its kind.
The man, named as 39 year old Mark Pollock, was able to take one thousand steps despite having been completely paralysed for four years.
It took five days for Pollock to learn to control the robotic exoskeleton, which relies on a non-invasive spinal stimulation technique to provide voluntary control over the device.
The researchers said Pollock is the first person with chronic complete paralysis who has been able to regain enough voluntary control to use the battery-powered bionic suit.
Pollock, who is also blind, has lost control over his body from the waist down after falling from a second-floor window four years ago.
The robotic technology could greatly improve his health by improving blood circulation in his lower limbs.
"In the last few weeks of the trial, my heart rate hit 138 beats per minute," Pollock said. "This is an aerobic training zone, a rate I haven't even come close to since being paralysed while walking in the robot alone, without these interventions. That was a very exciting, emotional moment for me, having spent my whole adult life before breaking my back as an athlete."
Before his injury, Pollock competed in ultra-endurance races across deserts, mountains and the polar ice caps. He also won silver and bronze medals in rowing at the Commonwealth Games and launched a motivational speaking business.
The UCLA team has previously managed to make completely paralysed people voluntarily move their legs in a rhythmic fashion without surgery.
"It will be difficult to get people with complete paralysis to walk completely independently, but even if they don't accomplish that, the fact they can assist themselves in walking will greatly improve their overall health and quality of life," said V. Reggie Edgerton, senior author of the research and a UCLA distinguished professor of integrative biology and physiology, neurobiology and neurosurgery.
The exoskeleton used in the study was provided by California-based Ekso Bionics. The suit automatically captures data, enabling the researchers to assess how much the subject is moving his own limbs, as opposed to being aided by the device.
"If the robot does all the work, the subject becomes passive and the nervous system shuts down," Edgerton said.
The data showed that Pollock was actively flexing his left knee and raising his left leg and that during and after the electrical stimulation, he was able to voluntarily assist the robot during stepping.
"For people who are severely injured, but not completely paralysed, there's every reason to believe that they will have the opportunity to use these types of interventions to further improve their level of function. They're likely to improve even more."