Ohio State University researchers have produced the first wearable sensor designed to detect and monitor muscle atrophy.
A condition involving the loss of skeletal muscle mass and strength, muscle atrophy can occur for a variety of reasons, but is usually a side effect of degenerative disease, aging, or muscle disuse.
While doctors currently rely on MRIs to assess whether a patient’s muscle size and bulk have deteriorated, frequent testing can be time-consuming and expensive.
However, this new study is published in the journal IEEE Transactions on Biomedical Engineering suggests that an electromagnetic sensor made of electrically conductive “electronic threads” could be used as an alternative to frequent MRI monitoring.
To validate their work, the researchers produced 3D-printed limb molds and filled them with ground beef to mimic the calf tissue of an average-sized human. Their results showed that they were able to demonstrate that the sensor could measure small volumetric changes in total limb size and monitor muscle loss of up to 51%.
“Ideally, our proposed sensor could be used by health care providers to make patient treatment plans more personalized and to create less burden on patients themselves,” said Alyanna Rice, lead author of the study and a graduate student in electrical and computer engineering at Ohio State University. .
The first known approach to monitoring muscle atrophy using a wearable device, the research builds on Rice’s previous work creating health sensors for NASA. The space agency is interested in monitoring the health of astronauts in various ways, as spending a lot of time in space can often have detrimental effects on the human body.
Researchers have spent decades trying to understand and combat these effects, and this study was inspired by the goal of finding solutions to the health problems faced by astronauts.
For example, while scientists know that even crew members can experience up to a 20% loss in muscle mass and bone density during short spaceflights, there isn’t much data on what effect living in space for longer missions might have on their bodies. , – said Rice.
“Our sensor is something that an astronaut on a long mission or a patient at home can use to monitor their health without the help of a medical professional,” she said.
But creating a wearable device capable of accurately measuring minute muscle changes in the human body is easier said than done. Rice and her co-author Asiminia Kiurti, a professor of electrical and computer engineering at Ohio State, designed the device to work using two coils, one for transmitting and one for receiving, and a conductor made of electronic filaments that run along the fabric in a distinct zigzag pattern.
Although the final product resembles a blood pressure cuff, Rice said it was initially a challenge to find a design that would allow for a wide range of changes in the size of the sensor loop so that it could fit a large portion of the population. .
“When we first proposed the sensor, we didn’t realize we would need a stretchable material until we realized that human limbs would change,” she said. “We need a sensor that can change and bend, but it also has to be uniform.”
After some trial and error, they discovered that while sewing in a straight line limited the elasticity of the sleeve, the zigzag pattern was perfect for enhancing it. This same new model is the reason the sensor can be scaled to different parts of the body or even multiple locations on a single limb.
​​​​​​While wearable devices are still years away, the study notes that the next big step is likely to be connecting the device to a mobile app that can be used to record and deliver health information directly to healthcare providers. .
And to improve the lives of future patients both on Earth and in space, Rice hopes to combine the sensor with other kinds of devices to detect and monitor health problems, such as a tool to detect bone loss.
“In the future, we’d like to integrate more sensors and even more capabilities with our wearable,” Rice said.
This work was supported by NASA.
