In a world first, surgeons have used a technique called deep brain stimulation to “re-awaken” dormant nerve fibres in the spinal cord and re-establish control of the leg muscles.
Two paralysed patients have been able to walk short distances and even climb stairs once more after being implanted with electrodes in their brains.
Both had catastrophic spinal injuries that meant they relied on a wheelchair before the operation.
But in a world first, surgeons used a technique called deep brain stimulation to “re-awaken” dormant nerve fibres in the spinal cord and re-establish control of the leg muscles.
Wolfgang Jaeger, 54, broke his back in a skiing accident in 2006 and had to shuffle downstairs on his backside.
But since being implanted with electrodes two years ago, he has worked intensively with physiotherapists to recover movement of his limbs.
He told Sky News: “If I want, I can walk a little bit, or go up and down the stairs, or if I need something in the kitchen where I have to stand up I can do it.
“[Technology] is getting better and better. In future I think we won’t need a wheelchair again.
“It’s a long way, but I think the dream comes true.”
The breakthrough came after neuroscientists at the Swiss Federal Technology Institute in Lausanne (EPFL) used artificial intelligence to map all the neurons in the brain involved in helping rats and mice walk.
To their surprise, a region called the lateral hypothalamus – known to be involved in arousal and motivation – was flagged as having a role in walking.
It was so unexpected that the finding was initially questioned by other scientists who approved the manuscript for publication in the journal Nature Medicine.
After successful tests in rodents, the Swiss team then implanted electrodes in the lateral hypothalamus of the human patients.
The technique, which is already widely used to control tremors in people with Parkinson’s disease, is carried out while patients are wide awake. Only then can surgeons be sure they have reached the right spot in the brain, with the right strength of stimulation.
‘I feel the urge to walk!’
Professor Jocelyne Bloch, who carried out the operations at Lausanne University Hospital, said: “Once the electrode was in place and we performed the stimulation the first patient immediately said, ‘I feel my legs’.
“When we increased the stimulation she said, ‘I feel the urge to walk!'”
Scientists believe the lateral hypothalamus marshals other parts of the brain to fire signals down nerve fibres that remain intact after the spinal injury.
The brain is needed to recover from paralysis
Prof Gregoire Courtine, the lead neuroscientist on the research team and co-director at the NeuroRestore centre in Lausanne, said: “The research demonstrates that the brain is needed to recover from paralysis.
“We found how to tap into a small region of the brain that was not known to be involved in walking in order to engage residual [nerve] connections and augment neurological recovery.”
