Wearable Sensors, Virtual Reality Give Seniors a New Lease on Life

Biomedical engineers and clinicians at the University of Arizona are developing devices that reduce risk of falling and increase quality of life for older adults with balance and mobility issues.

It is many senior citizens’ greatest fear: losing their balance and falling.

Their fears are well grounded. The U.S. Centers for Disease Control reports that over a third of adults 65 and older fall every year. The consequences are often devastating: crushing fractures, head injuries, excessive bleeding, institutionalization, and death.

The race is on to develop technology and treatments for preventing falls, and researchers at the University of Arizona, with a number of devices nearing commercialization, are at the forefront.

“Methods for predicting and preventing falls in older adults have been subjective and impractical,” said Bijan Najafi, director of the UA Interdisciplinary Consortium on Advanced Motion Performance, or iCAMP, and professor of biomedical engineering and surgery. “They include patient self-reporting, visual observations by clinicians, and testing in gait labs that mobility-impaired individuals must regularly visit.”

University of Arizona iCAMP researchers are testing sensor-based wearable devices that gather precise and objective information on mobility, balance and gait and transmit that data in real time to health care providers. The lightweight, easy-to-use devices detect patterns of activity that may lead to falls and help doctors treat patients who are at risk of falling.

Najafi is one of seven UA researchers participating in a new $75 million federally funded project to establish a Flexible Hybrid Electronics Manufacturing Innovation Institute, where manufacturing flexible medical monitoring devices will be one of the priorities.

Technology in Motion

As bed-bound patients at Banner-University Medical Center move their elbows up and down, a two-inch square wrist-worn sensor weighing less than two ounces measures biomechanical parameters such as torque and speed along with heart rate, pulse, blood pressure, respiration, fatigue and other physiological processes. Their data is transmitted over Bluetooth to a clinician’s laptop.

A 20-second arm-pumping test with biosensors gives iCAMP researchers precise data on a person’s health status.The patients are part of an iCAMP research project testing a low-cost biosensor to screen for frailty and personalize hospital care for the elderly. iCAMP investigators have been awarded -- in collaboration with BioSensics, a company that manufactures wearable medical devices -- a $1.5 million National Institutes of Health grant to clinically validate the system for commercialization.

“With just a 20-second test, we can determine if the patient is pre-frail or frail; if they can tolerate surgery; how long they should stay in the hospital, and whether they should be discharged to a rehab center or to their home,” Najafi said. “The technology is sophisticated, but the test itself is simple.”

The sensor includes a tri-axial gyroscope and tri-axial accelerometer. Technology involves signal processing, coding and iCAMP-developed biomechanical modeling algorithms.

Students Integral to Research

Dozens of UA Engineering and Health Science students are gaining clinical research experience working on iCAMP projects as research assistants, student workers and interns.

In summer 2015 Jaimeson Veldhuizen tested biosensors on residents of Sun City, Arizona, to measure cognitive impairment, another risk factor associated with falls.

“I really liked analyzing the data right after testing a participant to see how my observations compared with the actual results,” said Veldhuizen, a junior in biomedical engineering and one of several iCAMP interns in the Flinn Foundation Aging and Cognition Scholars Program. “In some cases, the data showed patients had higher levels of cognitive impairment than I thought.”

“Many of our students have gone on to publish their work and win awards, gotten into prestigious graduate programs, or been hired for excellent jobs,” said Jane Mohler, iCAMP associate director and professor of medicine, affiliated faculty with the Biomedical Engineering Graduate Interdisciplinary Program and associate director of the Arizona Center on Aging.

Virtual Obstacle Course

Najafi and colleagues have taken their biosensors a step further, creating virtual reality balance training games that boost confidence and improve balance in older adults, particularly those with diabetic peripheral neuropathy.

Up to half of older adults with diabetes experience peripheral neuropathy, which causes loss of sensation in the lower limbs. This makes walking difficult and may result in patients overlooking sores on their feet, which can become infected and require amputation. Diabetic-related amputations are a worldwide epidemic, numbering some 90,000 each year in the United States alone.

Researchers affix biosensors on a participant for a virtual reality balance training test in the iCAMP lab. Nearly 30 people have completed the training in the iCAMP lab. With biosensors strapped around their hips, thighs and ankles, they watch a stick figure representation of their legs on a computer screen as they balance on one foot and lift the other to step over virtual obstacles. The game gives them real-time feedback on how well they keep their balance while clearing the hurdles, and how to do better on their next try.

Researchers have observed 20 percent improvement in gait stability and velocity and 34 percent improvement in balance among participants in the virtual reality program.

The game taught one participant, a 73-year-old golfer with diabetic peripheral neuropathy who had begun falling down on the golf course, how to make a corrective hip motion when he felt unsteady. Now he is back in the game. Similarly, a 63-year-old woman said after the training that she could once again play again with her dogs.

“We try to improve not just the quantity of patients’ years, but the quality of their lives,” said Dr. David G. Armstrong, iCAMP scientific director, UA professor of surgery and biomedical engineering and director of the Southern Arizona Limb Salvage Alliance.

Wearable Tech from Head to Toe

When Najafi and his team founded iCAMP in 2012, they were focused on technologies to help older patients with diabetes.

The researchers made headlines in 2013 for SmartSox, fiber optic stockings embedded with biosensors that give physicians real-time data on diabetic patients’ feet and can detect foot ulcers before the patients do; and 3-D printed “smart” shoe insoles that detect abnormal pressure points on the soles of the feet and signal vulnerability to ulceration.

Today’s iCAMP wearable sensors and virtual reality balance training programs are not just for people with diabetes; people with osteoarthritis and osteoporosis, cancer, HIV, Parkinson’s disease, COPD, vertigo and stroke also stand to benefit from the technology.

Whatever the patient population or medical problem they’re addressing, iCAMP researchers are motivated by one basic question.

“You have an idea that you think will improve patients’ quality of life. Now, how do you prove it?” Najafi said.


Top picture: Bijan Najafi, left, and Dr. David G. Armstrong are helping to keep millions of older adults on their feet.