Wearable, flexible robotic device improves walking in people with Parkinson’s disease

Freezing is one of the most common and debilitating symptoms of Parkinson’s disease, a neurodegenerative disease that affects more than 9 million people worldwide. When people with Parkinson’s disease freeze, they suddenly lose the ability to move their feet, often mid-stride, resulting in a series of jerky steps that become shorter until the person stops completely . These episodes are one of the main contributing factors to falls in people with Parkinson’s disease.

Today, freezing is treated with a range of pharmacological, surgical or behavioral therapies, none of which are particularly effective.

What if there was a way to stop freezing completely?

Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Boston University’s Sargent College of Health & Rehabilitation Sciences used a soft, wearable robot to help a person with Parkinson’s disease to walk without freezing. The robotic garment, worn around the hips and thighs, gives a slight push to the hips as the leg swings, helping the patient take a longer stride.

The device completely eliminated participants’ freezing while walking indoors, allowing them to walk faster and further than they could without the aid of the garment.

“We found that just a small amount of mechanical assistance from our soft robotic clothing produced instantaneous effects and consistently improved walking across a range of conditions for the individual participating in our study,” said Conor Walsh, Professor Paul A .Maeder of engineering and applied sciences. Sciences at SEAS and co-corresponding author of the study.

The research demonstrates the potential of soft robotics to treat this frustrating and potentially dangerous symptom of Parkinson’s disease and could allow people living with the disease to regain not only their mobility but also their independence.

The research is published in Natural medicine.

For more than a decade, Walsh’s Biodesign Lab at SEAS has developed assistive and rehabilitative robotic technologies to improve mobility for individuals post-stroke and those living with ALS or other life-impacting illnesses. mobility. Part of this technology, in particular an exosuit for gait rehabilitation after a stroke, has been licensed and commercialized by ReWalk Robotics.

“Harnessing soft wearable robots to prevent freezing of gait in Parkinson’s disease patients required collaboration between engineers, rehabilitation scientists, physical therapists, biomechanists and clothing designers,” said Walsh, whose team worked closely with that of Terry Ellis, professor and department of physiotherapy. President and Director of the Boston University Neurorehabilitation Center.

The team spent six months working with a 73-year-old man with Parkinson’s disease who, despite the use of surgical and pharmacological treatments, endured significant and disabling freezing episodes more than 10 times a day, the causing it to fall frequently. These episodes prevented him from walking in his community and forced him to use a scooter to get around outside.

In previous research, Walsh and his team leveraged human-in-the-loop optimization to demonstrate that a wearable, flexible device could be used to increase hip flexion and help swing the leg forward to provide an effective approach to reduce energy expenditure during walking. in healthy individuals.

Here, the researchers used the same approach but to combat freezing. The wearable device uses cable-driven actuators and sensors worn around the waist and thighs. Using movement data collected by the sensors, the algorithms estimate gait phase and generate assistive forces in tandem with muscle movement.

The effect was instantaneous. Without any special training, the patient was able to walk without freezing indoors and with only occasional episodes outdoors. He was also able to walk and talk without freezing, which is rare without this device.

“Our team was really excited to see the impact of technology on participants’ walking,” said Jinsoo Kim, a former doctoral student. student at SEAS and co-lead author of the study.

During the study visits, the participant told researchers: “The suit helps me take longer steps and when it’s not active, I notice that I drag my feet a lot more.” This has really helped me and I think it’s a positive step forward. This could help me walk longer and maintain my quality of life.”

“Our study participants who donate their time are true partners,” Walsh said. “As mobility is difficult, it was a real challenge for this person to come to the lab, but we benefited enormously from his perspective and feedback.”

The device could also be used to better understand the poorly understood mechanisms of freezing of gait.

“Because we don’t really understand freezing, we don’t really know why this approach works so well,” Ellis said. “But this work suggests the potential benefits of a ‘bottom-up’ rather than ‘top-down’ solution to treating freezing of gait. We see that restoring near-normal biomechanics changes the peripheral dynamics of gait and can influence the central processing of walking. control.”

The research was co-authored by Jinsoo Kim, Francino Porciuncula, Hee Doo Yang, Nicholas Wendel, Teresa Baker and Andrew Chin. Asa Eckert-Erdheim and Dorothy Orzel also helped design the technology, as Ada Huang and Sarah Sullivan managed the clinical research.