• Posted January 8, 2024

Robotic Exosuit Can Eliminate 'Freezing' That Comes With Parkinsons

'Freezing' is a common and debilitating symptom of Parkinson's disease, with patients suddenly finding themselves unable to move their feet forward.

Drugs, surgeries and behavioral therapies have all proven rather ineffective against freezing, but Parkinson's patients might find fresh hope from a new, more sci-fi angle, researchers say.

A soft robotic exoskeleton appears able to help Parkinson's patients past a potential freezing episode, by providing a gentle push to the hips as their leg swings.

Researchers tested the exoskeleton on a 73-year-old man with Parkinson's who endured incapacitating freezing episodes despite prior treatment with surgery and drugs.

Without any special training, the exoskeleton allowed the patient to walk without any freezing episodes indoors and with only occasional episodes outdoors, researchers report.

The patient also walked faster and farther than he could without the device, and was able to walk and talk without freezing, which he couldn't often do without the exoskeleton.

"The suit helps me take longer steps and when it is not active, I notice I drag my feet much more,"the patient told researchers during the study. "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."

In freezing episodes, Parkinson's patients suddenly lose the ability to move their feet, often in mid-stride, researchers said.

Their feet move in a series of staccato stutter steps that become shorter and shorter, until the patient stops altogether.

Freezing episodes are hazardous to Parkinson's patients, as they are one of the biggest contributors to falls.

So, researchers at Harvard University and Boston University decided to create a soft, wearable robot exoskeleton to promote walking without freezing.

"We found that just a small amount of mechanical assistance from our soft robotic apparel delivered instantaneous effects and consistently improved walking across a range of conditions for the individual in our study,"researcher Conor Walsh, a professor of engineering and applied sciences at the Harvard John A. Paulson School of Engineering and Applied Sciences, said in a Harvard news release.

Previous studies by Walsh and his team had found that such a device could be used to augment hip movement and assist in swinging the leg forward, reducing the amount of energy that folks need to walk.

The wearable device uses cable-driven motors and sensors worn around the waist and thighs. Algorithms use motion data collected by the sensors to estimate a person's gait and provide assistance in tandem with muscle movement.

The new study was published Jan. 5 in the journal Nature Medicine.

Researchers hope that the device will provide new insights into why Parkinson's patients freeze.

"Because we don't really understand freezing, we don't really know why this approach works so well,"said researcher Terry Ellis, director of the Center for Neurorehabilitation at Boston University.

"But this work suggests the potential benefits of a 'bottom-up' rather than 'top-down' solution to treating gait freezing,"Ellis continued. "We see that restoring almost-normal biomechanics alters the peripheral dynamics of gait and may influence the central processing of gait control."

More information

The Parkinson's Foundation has more about freezing.

SOURCE: Harvard University, news release, Jan. 5, 2023