"I can now walk with much more confidence and my daily life has profoundly improved," Marc said during a press conference on a Tuesday.

The implant is described in a new study published today in Nature Medicine. Researchers at Lausanne University Hospital and the Swiss Federal Institute of Technology in Zurich led the study.

Parkinson's is a neurodegenerative disease that causes tremors, stiffness, and difficulty walking. As the disease progresses, most people have trouble walking or balancing and may experience "freezing," a temporary inability to move.

For more than 20 years, people with Parkinson's-related mobility issues have been treated using deep brain stimulation (DBS). DBS involves implanting electrodes in the brain to deliver electrical pulses to specific areas. DBS can be effective in improving mobility symptoms, but it does not cure Parkinson's and can have side effects such as dyskinesia (involuntary movements).

The new spinal neuroprosthesis may offer a new treatment option for people with Parkinson's who do not respond well to DBS or who experience side effects. The device is implanted in the lumbosacral spinal cord, which is the region of the spine that controls leg movements.

In Marc's case, the implant has allowed him to walk again after three years of being unable to do so. He can now walk for up to 30 minutes at a time without using a walker or cane.

"This is a remarkable breakthrough for the treatment of Parkinson's disease," said Jocelyne Bloch, a coauthor of the study and a neuroscientist at the Lausanne University Hospital. "We are hopeful that this device could help many people with Parkinson's regain their mobility and independence."

The researchers are now planning to test the spinal neuroprosthesis in six more people with Parkinson's disease. They are also working on developing a new version of the device that would be smaller and more user-friendly.

So, let us take a look at the study.

Researchers develop neuroprosthesis to alleviate gait impairments and balance problems in people with Parkinson's disease

Researchers have developed a neuroprosthesis that can alleviate gait impairments and balance problems in people with Parkinson's disease (PD). The neuroprosthesis works by targeting the dorsal root entry zones innervating lumbosacral segments to reproduce the natural spatiotemporal activation of the lumbosacral spinal cord during walking.

The researchers first developed the neuroprosthesis in a non-human primate model that replicates locomotor deficits due to PD. They found that the neuroprosthesis not only alleviated locomotor deficits but also restored skilled walking in this model.

They then implanted the neuroprosthesis in a 62-year-old male with a 30-year history of PD who presented with severe gait impairments and frequent falls. They found that the neuroprosthesis interacted synergistically with deep brain stimulation of the subthalamic nucleus and dopaminergic replacement therapies to alleviate asymmetry and promote longer steps, improve balance and reduce freezing of gait.

The researchers say that the neuroprosthesis opens new perspectives to reduce the severity of locomotor deficits in people with PD.

Requirements to alleviate gait deficits due to PD

We sought to develop a neuroprosthesis based on EES22–24 to restore the natural spatiotemporal activation of leg motor neurons that is disrupted during walking in people with PD. Therefore, we first determined the natural activation of leg motor neurons in healthy NHPs and how the administration of MPTP alters this activation. To record muscle activity, we developed a head-mounted system that enabled wireless recordings of electromyographic (EMG) signals from implanted leg muscles while NHPs walked without constraints or tethered electronics. We then visualized motor neuron activity by projecting the recorded EMG signals onto the known anatomical location of the motor neurons that produce these signals (Fig. 2a)22,23,30.

The resulting spatiotemporal maps of leg motor neuron activation revealed that walking involves the sequential activation of six well-defined hotspots located in the left and right hemicords. The sequential activation of these hotspots reflected the biomechanics of walking30, successively ensuring weight acceptance, propulsion and leg lift (Fig. 2a and Extended Data Fig. 2a). Comparison of maps recorded before and after the administration of MPTP revealed that locomotor deficits resulted from diverse alterations in the timing, duration and amplitude of each hotspot (Fig. 2a and Extended Data Fig. 2b). We, thus, reasoned that the ensemble of dorsal root entry zones projecting to these six hotspots must be targeted to alleviate gait impairments and balance problems.

Brain-controlled neuroprosthesis restores walking ability in non-human primates with Parkinson's disease

Researchers have developed a brain-controlled neuroprosthesis that can alleviate gait impairments and balance problems in non-human primates (NHPs) with Parkinson's disease (PD). The neuroprosthesis works by decoding motor intentions from the primary motor cortex and using these predictions to synchronize the timing and location of electrical stimulation bursts delivered to the spinal cord.

The researchers first identified six hotspots in the spinal cord that are responsible for producing walking. They then implanted microelectrode arrays into the primary motor cortex of two MPTP-treated NHPs and recorded neural activity during walking. They found that the neural firing patterns were highly regular and phase locked to gait cycles, suggesting that motor intentions can be reliably decoded from motor cortex activity.

Next, the researchers implanted electrode arrays over the spinal cord and interfaced them with an implantable pulse generator. They created a regularized linear discriminant analysis (rLDA) algorithm that accurately found the six hotspots that were activated by motor cortex activity.

Finally, the researchers integrated all of these components to create a wireless brain-controlled neuroprosthesis. They tested the neuroprosthesis in three MPTP-treated NHPs and found that it immediately alleviated gait impairments and balance problems. The NHPs were able to walk as rapidly as before the administration of MPTP and their gait quality and balance improved significantly.

The researchers also found that the neuroprosthesis complements deep brain stimulation (DBS), the primary neurosurgical intervention to alleviate motor signs of PD. In one MPTP-treated NHP, the neuroprosthesis improved gait and balance even further when combined with DBS.

These results suggest that brain-controlled neuroprosthetics could be a promising new treatment for gait impairments and balance problems in people with PD. Further studies are needed to test the safety and efficacy of this technology in humans.

A summary of the key findings of the study:

• Researchers developed a brain-controlled neuroprosthesis that can alleviate gait impairments and balance problems in NHPs with PD.

• The neuroprosthesis works by decoding motor intentions from the primary motor cortex and using these predictions to synchronize the timing and location of electrical stimulation bursts delivered to the spinal cord.

• The neuroprosthesis immediately alleviated gait impairments and balance problems in three MPTP-treated NHPs.

• The neuroprosthesis complements DBS, the primary neurosurgical intervention to alleviate motor signs of PD.

Brain-controlled neuroprosthesis shows promise for treating gait impairments and balance problems

Researchers have developed a neuroprosthesis that can alleviate gait impairments and balance problems in people with Parkinson's disease (PD). The neuroprosthesis works by decoding motor intentions from the brain and using this information to stimulate the spinal cord in a way that restores the natural activation of leg motor neurons.

In a first-in-human clinical trial, the researchers implanted the neuroprosthesis in a 62-year-old man with PD who had severe locomotor deficits. The neuroprosthesis was able to significantly improve the man's gait and balance, and he was able to reduce his fall rate from 2-3 falls per day to nearly zero.

The researchers also found that the neuroprosthesis can complement deep brain stimulation (DBS), the most common surgical treatment for PD. In one animal experiment, the neuroprosthesis was able to further improve the gait and balance of a non-human primate with PD that was already receiving DBS.

These results suggest that brain-controlled neuroprosthetics could be a promising new treatment for gait impairments and balance problems in people with PD. Further studies are needed to confirm the long-term safety and efficacy of this technology in humans.

• Brain-controlled neuroprosthetics can alleviate gait impairments and balance problems in people with PD.

• The neuroprosthesis works by decoding motor intentions from the brain and using this information to stimulate the spinal cord in a way that restores the natural activation of leg motor neurons.

• The neuroprosthesis can complement deep brain stimulation, the most common surgical treatment for PD.

• Headline: Brain-controlled neuroprosthesis shows promise for treating gait impairments and balance problems in Parkinson's disease

Neuroprosthesis restores walking ability and reduces freezing of gait in a person with Parkinson's disease

Researchers have developed a neuroprosthesis that can restore walking ability and reduce freezing of gait in people with Parkinson's disease (PD). The neuroprosthesis works by decoding motor intentions from the brain and using this information to stimulate the spinal cord in a way that restores the natural activation of leg motor neurons.

In a first-in-human clinical trial, the researchers implanted the neuroprosthesis in a 62-year-old man with PD who had severe locomotor deficits and frequent falls. The neuroprosthesis was able to significantly improve the man's gait and balance, and he was able to reduce his fall rate to nearly zero.

The neuroprosthesis was also able to reduce the man's freezing of gait, which is one of the most debilitating locomotor deficits of PD. Freezing of gait is an episodic inability to move the legs, and it is often triggered by turning or walking through narrow spaces. The neuroprosthesis was able to nearly eliminate the man's freezing of gait episodes in both simple and complex walking environments.

In addition to improving gait and balance, the neuroprosthesis also allowed the man to participate in a rehabilitation program that further improved his endurance and quality of life. He is now able to walk and participate in activities of daily living without any additional assistance.

The results of this study suggest that brain-controlled neuroprosthetics could be a promising new treatment for gait impairments and freezing of gait in people with PD. Further studies are needed to confirm the long-term safety and efficacy of this technology in a larger number of patients.

• Brain-controlled neuroprosthesis can restore walking ability and reduce freezing of gait in a person with PD.

• The neuroprosthesis works by decoding motor intentions from the brain and using this information to stimulate the spinal cord in a way that restores the natural activation of leg motor neurons.

• The neuroprosthesis is safe and effective for long-term use.

• The neuroprosthesis can be used to support rehabilitation and improve quality of life in people with PD.

Discussion

This study presents a first-in-human demonstration of a neuroprosthesis that can reduce gait impairments, balance problems, and freezing of gait in people with Parkinson's disease (PD). The neuroprosthesis is put into the lumbosacral spinal cord and sends electrical signals to the dorsal root entry zones. These are where large-diameter afferent fibers enter the spinal cord. The stimulation changes the activity of groups of motor neurons that help you walk. This makes up for the fact that PD-related leg motor neurons do not work properly.

The neuroprosthesis was developed in MPTP-treated non-human primates and validated in one person with PD. The results showed that the neuroprosthesis significantly improved gait and balance, and reduced freezing of gait episodes in the participant. Additionally, the neuroprosthesis and gait rehabilitation improved the participant's neurological condition and quality of life.

Despite the promising results, the study has several limitations. First, it was conducted in a single participant, so it is unclear how well the neuroprosthesis will generalize to other people with PD. Second, the neuroprosthesis is still under development, and purpose-built technologies optimized for the specific requirements of people with PD are needed to scale up this therapy.

Future studies will need to identify the responders to this therapy and develop more user-friendly and reliable technologies to detect motor intentions and deliver electrical stimulation. However, the conceptual and technological feasibility of a brain-controlled neuroprosthesis for PD has been established in this study.

Key takeaways

When a neuroprosthesis is put into the lumbosacral spinal cord, it can help people with Parkinson's disease walk more normally and avoid falling or losing their balance.

The neuroprosthesis changes the activity of groups of motor neurons that help you walk. This makes up for the fact that PD-related leg motor neurons do not work properly.

The neuroprosthesis significantly improved gait and balance, and reduced freezing of gait episodes in a single participant with PD.

Further studies are needed to identify the responders to this therapy and develop purpose-built technologies optimized for the specific requirements of people with PD.