By Michelle Roberts
Digital health editor
A man with advanced Parkinson's disease has been helped to walk again with a special implant that stimulates nerves in his spine.
Marc Gauthier, 63, from Bordeaux, France, the first person to try out the device, says it has given him a second chance in life.
He can now walk for miles, when previously he was often housebound and had several falls a day.
The medical team treating him describe the advance in Nature Medicine journal.
Before the implant, navigating steps or going into a lift posed extra problems for Marc.
The treatment appears to have stopped the shuffling and "freezing" or sudden stopping Marc and many Parkinson's patients struggle with - and now, when the device is switched on, his gait looks almost normal.
Marc said: "Getting into an elevator... sounds simple. For me, before, it was impossible.
"I turn on the stimulation in the morning and I turn off in the evening. This allows me to walk better and to stabilise. Right now, I'm not even afraid of the stairs anymore. Every Sunday, I go to the lake, and I walk around 6km [four miles]. It's incredible."
Marc feels "a little tingling sensation", when the device is on, but is not bothered by it.
How it works
The stimulator sits on the lumbar region of the spinal cord, which sends messages to the leg muscles.
Marc is still in control - his brain gives the instructions - but the epidural implant adds electrical signals for a smoother end result.
It is wired to a small impulse generator with its own power supply, implanted under the skin of Marc's abdomen.
After surgery to fit the device, Marc had weeks of rehabilitation to programme it, using feedback sensors on his legs and shoes.
Neurosurgeon Jocelyne Bloch, who fitted Marc's device, almost two years ago, said the technology and procedure was similar to that which had helped some spinal-injury patients for many years - but it was a first for Parkinson's disease, although other teams are exploring different techniques.
She said: "It is impressive to see how by electrically stimulating the spinal cord in a targeted manner, in the same way as we have done with paraplegic patients, we can correct walking disorders caused by Parkinson's disease."
Eduardo Martin Moraud, an expert from NeuroRestore, which made the implant initially tested in animals, said Marc was a pioneer:
"He was very courageous to be the first one," Mr Moraud said. "We were extremely happy to see how it could bring so many benefits to someone."
Brain stimulation
The work is a collaboration between the Swiss Federal Institute of Technology in Lausanne, the city's hospital and university, the French National Institute of Health and Medical Research and the University of Bordeaux.
One of the team, Prof Grégoire Courtine, said more work was needed to see whether it could help other Parkinson's patients.
"This is only one participant and we don't know whether all the individuals with Parkinson's disease will respond to the therapy," he said.
The team will now try the device in six more Parkinson's patients, using funding from the Michael J Fox Foundation.
For some, a brain implant - deep brain stimulation - might be able to do the job instead. But the medical team told a press briefing that had not been not an option for Marc, who already had an older brain implant that would have been hard to replace.
The treatment is not a cure - Parkinson's is a progressive condition that worsens over time.
Those with the disease have too little of the chemical dopamine in their brain because some of the nerve cells that make it have stopped working.
- involuntary shaking of parts of the body
- slow movement
- stiff and inflexible muscles
Parkinson's UK research director David Dexter said: "This is quite an invasive procedure but could be a game-changing technology to help restore movement in people with advanced Parkinson's, where the drugs are no longer working well.
"The research is still at a very early stage and requires much more development and testing before it can be made available to people with Parkinson's. However, this is a significant and exciting step forward and we hope to see this research progress quickly."
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