Scientists from University of California-Los Angeles report how a man paralyzed from the waist down has been able to move his legs voluntarily with the help of a "robotic exoskeleton."
Thirty-nine-year-old Mark Pollock had been completely paralyzed for 4 years after falling out of a window.
In a new study, Prof. V. Reggie Edgerton, senior author and a UCLA distinguished professor of integrative biology and physiology, neurobiology, and colleagues reveal how the robotic device enabled the man to control his leg muscles voluntarily and take thousands of steps.
The "step-like" movements are an advance on previous efforts by the same research team that saw five men with a similar condition to Pollock make rhythmic movements with their legs.
In that instance, the team used physical rehabilitation exercises and electrical stimulation therapy, achieved through an invasive epidural stimulator that they implanted into the patient's spinal cord.
This latest research combines a new noninvasive spinal stimulation technique with a battery-powered wearable bionic suit.
The researchers report how - after completing 5 weeks of physical training, followed by five 1-hour sessions using spinal stimulation training - Pollock has become the first person to achieve voluntary control with a robotic device that aims to enhance mobility.Data capture from the robotic device enables researchers to measure to what degree a patient is moving their limbs themselves, and how much is done by the device.
Robotic device may allow paralyzed patients 'to assist themselves with walking'
In this current research, the team found that Pollock was actively and voluntarily flexing his left knee and raising his leg both during and after electrical stimulation, working with the robotic exoskeleton to produce these movements rather than leaving the device to do all the work.
Having spent his whole life as an athlete, completing extreme adventures such as racing to the South Pole before breaking his back, Pollack was thrilled to get back to doing an aerobic workout.
"Stepping with the stimulation and having my heart rate increase, along with the awareness of my legs under me, was addictive. I wanted more," he says.
Around 5,596,000 people in the US report some kind of paralysis. The leading cause of the condition is stroke, followed by spinal cord injury and multiple sclerosis (MS). Other causes of paralysis include neurofibromatosis, cerebral palsy and post-polio syndrome.
Prof. Edgerton and colleagues hope that the type of intervention described in their research may improve mobility for patients with partial paralysis.
"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."
"What we are seeing right now in the field of spinal cord research is a surge of momentum with new directions and approaches to remind the spine of its potential even years after an injury," notes Peter Wilderotter, president and CEO of the Christopher and Dana Reeve Foundation, who helped fund the research.
Written by Jonathan Vernon