Researchers develop robotic wearable device to improve walking for individual with Parkinson’s disease

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and the Boston University Sargent College of Health & Rehabilitation Sciences recognised that freezing is one of the most common symptoms of Parkinson’s disease.

The freezing symptom means individuals with Parkinson’s suddenly lose the ability to move their feet, often mid-stride, resulting in a series of staccato stutter steps that get shorter until, researchers said, the person stops altogether.

Researchers said the symptom is currently treated with a range of pharmacological, surgical or behavioural therapies, none of which are particularly effective.

This researchers developed a robotic garment, worn around the hips and thighs, that gives a gentle push to the hips of the individual as their leg swings, helping the patient achieve a longer stride.

The team spent six months working with a 73-year-old man with Parkinson’s disease, who — despite using both surgical and pharmacologic treatments — endured substantial and incapacitating freezing episodes over 10 times a day, causing him to fall frequently.

The device uses cable-driven actuators and sensors worn around the waist and thighs. Using motion data, algorithms estimate the phase of the gait and generate assistive forces in tandem with muscle movement.

Researchers said the effect was ‘instantaneous’. Without any special training, the patient was able to walk without any freezing indoors and with only occasional episodes outdoors. He was also able to walk and talk without freezing, a rarity without the device.

In a statement, Terry Ellis, professor and Physical Therapy Department chair and director of the Center for Neurorehabilitation, Boston University, said: “Because we don’t really understand freezing, we don’t really know why this approach works so well, but this work suggests the potential benefits of a ’bottom-up’ rather than ’top-down’ solution to treating gait freezing.

“We see that restoring almost-normal biomechanics alters the peripheral dynamics of gait and may influence the central processing of gait control.”

During the study visits, the participant said: “The suit helps me take longer steps and when it is not active, I notice I drag my feet much more. It has really helped me, and I feel it is a positive step forward. It could help me to walk longer and maintain the quality of my life.”

“Our study participants who volunteer their time are real partners,” said Conor Walsh, the Paul A. Maeder professor of Engineering and Applied Sciences at SEAS. “Because mobility is difficult, it was a real challenge for this individual to even come into the lab, but we benefited so much from his perspective and feedback.”

The research was supported by the US National Science Foundation, the US National Institutes of Health, and the Massachusetts Technology Collaborative, Collaborative Research and Development Matching Grant.

Published in Nature Medicine, the research paper can be accessed in full here.