A new implant that boosts the signals sent from the brain to the limbs has been found to significantly improve mobility in people living with Parkinson’s disease. The study was published in the Canadian Journal of Neurological Sciences last month.
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Parkinson’s disease is a progressive, neurological condition that affects around 145,000 people in the UK. Symptoms of Parkinson’s disease begin to appear when the brain can no longer produce enough dopamine, the neurotransmitter that is used to control movement.
Those living with Parkinson’s can often experience ‘freezing’ episodes, where movements such as walking or turning around are interrupted, causing them to suddenly not able to move forward for up to several minutes. Freezing may also occur while someone is speaking or during repetitive activities like writing. The exact cause behind these freezing episodes is not currently understood.
Signaling issues in the brain
In order to walk, the brain needs to send signals to the limbs to trigger movement. Signals then return to the brain to inform it that the movement has been completed, and the cycle begins again to trigger further steps.
Professor Mandar Jog of Western University in London, Ontario, believes that Parkinson’s disease reduces the signals that return to the brain once a movement has been completed. This causes Parkinson’s disease sufferers to freeze, when the movement trigger cycle is broken by weak signal transmission to and from the brain.
This is in contrast to the previous hypothesis that it was the signals going from the brain to the limbs that were not being transmitted correctly.
Boosting brain signaling pathways to improve mobility
A quarter of patients with Parkinson’s have difficulty walking as the condition progresses, but there are currently no treatments to alleviate this specific symptom of the condition.
But now, Professor Jog and his research team have developed an implant that boosts the signals travelling to and from the brain and limbs, allowing the patient to walk normally. Using bursts of electricity from the implant, Jog believes that the feedback mechanisms from the legs to the brain are reawakened, causing a significant improvement in a person’s ability to walk.
The team also found that the treatment was long-lasting and continued to be affective even when the implant was turned off.
This is a completely different rehabilitation therapy. We had thought that the movement problems occurred in Parkinson’s patients because signals from the brain to the legs were not getting through. But it seems that it’s the signals getting back to the brain that are degraded.”
Professor Mandar Jog, Lead Author
From house-bound to vacations and trips to the mall
Deep brain stimulation of the subthalamic nucleus, often shortened to DBS-STN, has also been the subject of studies investigating how different frequencies, amplitudes, and pulse-width electrical parameter settings can improve problems with voice quality, speech intensity, and prosody of speech in Parkinson’s patients. One such study found that DBS-STN was “associated with improved speech outcomes.”
“Most of our patients have had the disease for 15 years and have not walked with any confidence for several years,” Jog explained.
He added that it was “beyond his wildest dreams” to see such significant improvements as a result of his research: “For [patients] to go from being home-bound, with the risk of falling, to being able to go on trips to the mall and have vacations in remarkable for me to see.”
Case studies
One success story saw Gail Jardine, 66, being able to walk freely for the first time in over two years. Before having the implant fitted, Jardine was experiencing regular freezing episodes and falls up to two or three times a day.
The risk of injury and loss of confidence from these debilitating Parkinson’s symptoms prevented Jardine from enjoying countryside walks with her husband Stan in Kitchener, Ontario. On the improvements she has seen since having the implant fitted, Jardine said:
I can walk a lot better. I haven’t fallen since I started the treatment. It’s given me more confidence and I’m looking forward to taking more walks with Stan and maybe even go on my own.”
Another person benefitting from the implant treatment is Guy Alden, 70, who had to retire from his work as a deacon at a catholic church in London, Ontario, on account of his Parkinson’s disease.
“I was freezing a lot when I was in a crowd or crossing a threshold in a mall. Everyone would be looking at me. It was very embarrassing,” Alden said.
Now I can walk in crowds. My wife and I even went on holiday to Maui and I didn’t need to use my wheelchair at any point. There were a lot of narrow roads and a lot of [slopes] and I did all of that pretty well.”
'Very promising' results
Dr. Beckie Port, who is a research manager at Parkinson’s UK, said:
“The results seen in this small-scale pilot study are very promising and the therapy certainly warrants further investigation. Should future studies show the same level of promise, it has the potential to dramatically improve quality of life, giving people with Parkinson’s the freedom to enjoy everyday activities.”
If you have been affected by Parkinson’s or known somebody who may need support, please go to our dedicated support page.
Journal reference:
Abeyesekera, A., Adams, S., Mancinelli, C., Knowles, T., Gilmore, G., Delrobaei, M., & Jog, M. (2019). Effects of Deep Brain Stimulation of the Subthalamic Nucleus Settings on Voice Quality, Intensity, and Prosody in Parkinson’s Disease: Preliminary Evidence for Speech Optimization. Canadian Journal of Neurological Sciences / Journal Canadien Des Sciences Neurologiques, 46(3), 287-294. doi:10.1017/cjn.2019.16