MyoExo: Wearable Muscle-Centric Sensors for Improved Assessment of Neurological Disorders

The Problem

Abnormal changes in muscle function are hallmarks of a collection of neurological disorders, including Parkinson’s Disease (PD), essential tremor, epilepsy, certain sleep disorders, and others. For example, patients with PD can have slowed movements (bradykinesia), tremors, and muscle stiffness (rigidity) – doctors need to detect at least two of the three signs for a positive diagnosis. Patients suffering from essential tremor, a disease separate from PD, experience involuntary rhythmic shaking of different muscles, while patients with epilepsy are beset by sudden muscle contractions that appear as sudden brief jerks or twitches.

Importantly, detecting and monitoring these neurological disorders remains a major obstacle to early diagnosis, patient care, and the development of better therapies. Since muscle symptoms can vary dramatically between patients with one disorder and overlap between disorders, the development of standard tests has been challenging. The diagnosis of these various disorders is often subjective and a trial and error approach of seeing how patients respond to various drugs is often required. This lack of biomarkers for this class of diseases complicates especially early diagnosis when symptoms are still mild. Improving early accurate diagnosis is also essential because studies showed that early diagnosis benefits patient quality of life over the course of the disease. In fact, up to 42% of patients with PD were reported to have been misdiagnosed early in their disease, and misdiagnosis rates are even higher (37 to 50%) for patients with essential tremor. In addition, many of these diseases are progressive and medication dose and timing needs to be adjusted and optimized over time, and ways to remotely assess medication effectiveness is needed for existing drugs, and also important for studying effectiveness of new ones.

Several commercial products have emerged over the past two decades attempting to meet the need for objective detection and monitoring of movement symptoms, but most of these products depend on inertial measurement technologies (the kind used in smartphones to determine their orientation) to detect the movement of an individual. These systems can monitor limb motion (and thus bradykinesia and tremor) but not muscle rigidity, which is present in more than 90% of patients with PD.

Our Solution

Members of the Harvard Biodesign and Microrobotics labs, led by Wyss Associate Faculty members Conor Walsh, Ph.D. and Robert Wood, Ph.D., are developing the MyoExo system with integrated novel wearable strain sensor technology to accurately detect and monitor muscle rigidity in PD patients.

The soft wearable system is “muscle-centric” compared to the inertia-based sensor systems currently on the market, and is designed to be comfortable enough to be worn by a patient all day. The sensors can detect distinct physiological patterns in the patient’s muscles multiple times throughout the day, which can produce much more information about a patient’s condition than brief check-ups a few times a year. This will allow healthcare providers to more effectively manage symptoms in neurological disorders and make adjustments to treatment. It could also potentially help detect the disease much earlier and improve patients’ quality of life by reducing the risk of falling.

Our vision is that the MyoExo device can be used without the assistance of a medical specialist, enabling a telehealth approach to treatment and reducing the cost to healthcare payers and providers. The system is also well-poised for use in both traditional and virtual clinical trials, as it could provide objective and reliable indicators of whether a drug candidate is improving symptoms or impacting disease progression.

Product Journey

After developing their first fully functional fabric-based sensor, the research team, spearheaded by Seun Araromi, Ph.D., a Research Associate in Materials Science and Mechanical Engineering at the Wyss Institute and Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS), engaged in discussions with the Wyss Institute’s business development team and decided to focus on PD for its first use case.

After the MyoExo project was named a Wyss Institute Validation Project in 2020, they quickly moved to involve patients with PD in their research by partnering up with Terry Ellis, Ph.D., P.T., FAPTA, Professor of Boston University Sargent College of Health & Rehabilitation Sciences. Since then, Ellis’ group recruited patients with PD for a clinical study, and provided continuous feedback about its comfort and functionality while testing multiple iterations of the device.

Placed on muscles of persons with PD in the trial, the MyoExo sensors robustly registered subtle changes in the curvature of muscles that occur when muscles become rigid and, importantly, proved to be a reliable test for distinguishing different levels of response to medication. This new approach could help to more accurately classify individuals with PD into those responsive to medication and those non-responsive, and could be an important step toward finding more personalized treatments. In addition, MyoExo sensors could help separate PD from other disorders, and accurately diagnose disorder-specific muscle dysfunctions.

Impact

While PD is the fastest-growing neurodegenerative condition in the world, second only to Alzheimer’s, and effects 600,000 Americans every year, other neurological disorders with muscle dysfunctions also cause significant patient suffering and costs to healthcare systems.

The team plans to launch a startup to commercialize the MyoExo technology and make it available to persons suffering from PD and other neurological disorders.