A team of scientists based in Sao Paulo, Brazil have been working with a number of patients classed as having total paralysis after spinal injuries. Like many other teams around the world they were looking for a way to help people with paralysis move their limbs again using an exoskeleton – a framework that is fastened to the relevant body parts and makes them move when instructed to. The idea was that by combining virtual reality (VR) equipment with an exoskeleton, patients could learn to move the exoskeleton (and therefore their paralysed limbs) just by thinking about it. To make it more realistic the VR system was combined with haptic feedback – in the same way that swiping your finger across a touchscreen can produce feedback in the form of faint vibrations, the VR system gave the patients the sensation that their feet were touching the ground.
But the Walk Again Project, which includes scientists from 25 countries, seems to have been even more successful than the researchers had hoped. Writing in the journal Scientific Reports this week, the team reported that after 10 months of training with the combined exoskeleton and VR system eight of their patients had actually regained some sensation and movement where previously there was none.
It was originally thought that the patients had had all their spinal nerves severed, but the researchers now believe that in these eight patients a small number of nerves survived intact but dormant. When they trained using the VR system, haptic feedback and exoskeleton, these nerves awakened and over time the neurons in the brain became able to receive signals from the newly active nerves. This meant that the patients regained some sensation, especially in terms of sensing pain, pressure and vibration. They noticed increased bladder and bowel control as well as the ability to move their lower limbs. One patient is now able to drive a car, while another can walk using leg braces and crutches. One woman was even able to conceive and deliver a baby, feeling the contractions where before she had had no sensation at all.
Of course, it’s early days and there’s a lot of work ahead. But a project that was originally designed to help people with paralysis move with an exoskeleton may have become a project that can help them regain movement and sensation that was thought to be lost forever.
Featured image: an Oculus Rift prototype, by Maurizio Pesce