Wireless body sensors to help prevent falls in seniors

Apr 14 2009

When an older person is injured in a fall, the cost is significant, both in quality of life and medical expense.

Wireless body sensor networks that monitor gait, being developed by University of Virginia researchers, could offer a solution on both fronts.

A new consortium of researchers from U.Va.'s School of Engineering, School of Medicine and Department of Psychology, in partnership with the U.Va. Institute on Aging's Translational Research Consortium and AFrame Digital, Inc., a health monitoring and medical alert products company, will soon be providing the wearable sensors to residents of some area long-term care facilities.

The group will use continuous data from these "living laboratories" to test and refine the technology.

"We are moving research from the lab to a living environment," said Regina Carlson, director of development for the Institute on Aging.

"Ultimately, we will gain better research data in these settings."

Falls are the leading cause of injury death among people age 65 and older, according to research compiled by the Centers for Disease Control and Prevention. They are also the major cause of non-fatal injury and hospitalizations for trauma. By 2020, the annual direct and indirect cost of fall injuries is projected to reach $54.9 billion.

The tool being developed at U.Va. will aid in the identification of gait problems that may result in falls. By wirelessly connecting to a network set up by AFrame Digital, the sensors will provide researchers with real-time data on the nursing home residents' gaits. Using this information, the researchers are working to commercialize a product that will eventually allow geriatricians to accurately assess gait problems and provide the proper interventions - such as a walker - before a fall happens.

This type of sensor technology is also a key component for transitioning to more health care being delivered in patients' homes. Proponents of the shift, including the U.Va. researchers, believe this will help keep health care costs down and promote a better quality of life for patients.

John Lach, an associate professor in the Charles L. Brown Department of Electrical and Computer Engineering, has been researching and developing wireless body sensors for the past five years. In this application, the sensors can be worn like a wristwatch. Using parameters determined in a gait laboratory directed by D. Casey Kerrigan, a professor in the School of Medicine's Department of Physical Medicine and Rehabilitation, Lach has developed sensors that can quantitatively measure the walking patterns that are likely to lead to falls.

Lach's sensors, now about the size of a digital watch face, can measure and transmit data on a wide range of human motion, including linear acceleration, or how fast patients move in a straight path, and rotational rate, which together provide six degrees of freedom motion capture. The sensors are now in their third generation of development and, thanks to the living laboratory model, they will now evolve with faster prototyping cycles that use continuous feedback from the patients.

Currently, monitoring gait-related problems typically requires patients to visit a health care facility, where they walk on a pressure sensitive treadmill and are monitored by video cameras. While accurate, this approach is costly and limited in its application.

Lach's research has the potential to create a new standard of care - one that is ultimately more cost-efficient and applicable to myriad real-world settings. While the current project focuses on gait problems in the elderly, the same technology could potentially be used by the military to monitor and analyze soldiers' movements in combat situations.

While gathering the parties necessary to carry out this project was challenging, the multi-disciplinary approach is proving essential to the project's success. The diversity of expertise also helps ensure the research will have real-world-relevance.

"This research wouldn't be possible without these relationships," Lach said.

By working with the U.Va. Engineering School's Office of Corporate and Foundation Relations, the researchers aligned with Virginia-based AFrame Digital.

AFrame's nonintrusive wireless monitoring and alerting system is designed to enhance the independence and security of residents and patients as they move about in a long-term care facility during their activities of daily living, so that they experience greater peace of mind and confidence for a fuller and more active lifestyle. Data from sensors is securely analyzed in the system to provide a private and nonintrusive indication of status to caregivers.

"We are very proud to have the opportunity to collaborate with the Institute on Aging and leading researchers at the University of Virginia," said Bruce Wilson, AFrame's chief operating officer. "Research-based innovations in health and wellness will help to reduce health care costs and improve the quality of life for our elder population."

"This project presented a prime opportunity for our researchers to work with AFrame," said Tony Kinn, director of corporate relations at the U.Va. Engineering Foundation. "We are bringing the talents and resources of U.Va. to bear against an issue that will benefit many groups - researchers who are developing the technology, a company that can help commercialize it and ultimately older adults who will enjoy safer and healthier lives."

Beyond physical injury, falls can by psychologically harmful, especially as they relate to older adults' sense of independence. The Department of Psychology is interested in researching how this technology will benefit the psychological wellbeing of residents and patients in long-term care facilities.

"We are breaking barriers between the research world and long-term care facilities," Donna Hearn, assistant chair for the Department of Psychology, said. "What we are doing will make a difference on the ground and in health care costs."

Carlson said the new technology combines social and psychological wellbeing with a host of interrelated services. "With this technology we can promote independent living at a lower cost because it can be delivered to patients in their home," she said.