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Bijan Najafi: One Foot in Engineering, the Other in Medicine

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Bijan Najafi: One Foot in Engineering, the Other in Medicine

May 1, 2014
Bijan Najafi and his research team bring biomechanics and biomedical modeling to medicine, so people with diabetes stand a better chance of keeping their feet and seniors avoid the devastating consequences of falls.

Preventing Diabetic Ulcers with SmartSox

For people who have diabetes, high-tech socks may mean the difference between keeping their feet and losing them to amputation.

Bijan Najafi, right, director of iCAMP, and Gurtej Singh Grewal, UA research associate, demonstrate a wearable activity sensor, in the form of a wristwatch, designed to help seniors avoid falls.

Over time, people with diabetes, who are newly diagnosed at the rate of one every 17 seconds in the United States, can lose sensation in their peripheral nervous system, which makes them unaware of developing foot ulcers. Left untreated, foot infections can have severe consequences, like amputation. Diabetic foot ulceration comes with an estimated 25 percent lifetime risk, and diabetes-related amputation occurs somewhere in the world every 20 seconds, about 90,000 a year in the United States alone.

However, amputations are largely preventable, said UA biomedical engineer Bijan Najafi, whose SmartSox may well be part of the solution.

SmartSox measure three parameters critical in the management of diabetes -- temperature, pressure and joint angles in the foot -- and report data via a combination of sensors and fiber optics.

“For the first time, we have the technology to measure all three parameters simultaneously and during daily activity to help us identify the area of the foot most likely to develop an ulcer,” said Najafi, who directs the Interdisciplinary Consortium on Advanced Motion Performance, or iCAMP.

iCAMP is researching the effectiveness of SmartSox with the UA Southern Arizona Limb Salvage Alliance, or SALSA. The work is supported by more than $2 million in grants from the Qatar National Research Fund.

“Diabetic foot wounds tend to heat up before the skin breaks down,” added SALSA director Dr. David Armstrong. Sophisticated textiles, like SmartSox, “can detect heat and allow patients to identify ulcers on the bottom of their feet before the infection has a chance to spread too far.”

Studying How We Move Through the World

Najafi also has developed biomechanical models of the human body and combined them with small, low-cost sensors that can be embedded in socks, shirts, straps, patches and other devices to study physical activity patterns, gait and balance parameters, and three-dimensional joint structures.

“My main focus is the quantification of quality of mobility, studying how people move through the world,” said Najafi, associate professor of biomedical engineering, surgery, and medicine. “I directly interact with the clinicians who know the problem, and as engineers we try to provide solutions.”

iCAMP’s research and development consortium, including clinicians, research scientists and biomedical engineers from across the UA campus, brings human motion assessment technology to many areas of clinical medicine.

Najafi is a member of the UA’s Center on Aging, the UA Cancer Center, and the Arizona Arthritis Center scientific advisory board. He also is a Biomedical Engineering Graduate Interdisciplinary Program faculty member. Before coming to the UA in 2012, Najafi directed the Dr. Scholl’s Human Performance Laboratory at the Rosalind Franklin University of Medicine and Science in Chicago. He earned a PhD in biomedical engineering from Swiss Federal Institute of Technology and has published more than 100 peer-reviewed articles.

Improving Seniors’ Quality of Life

About 30 percent of people 65 and older experience at least one fall a year because their gait and balance have declined, especially while dual tasking -- for example, walking while talking. This percentage increases to 40 percent after age 75. Falls often result in fractures, head injuries, and post-fall anxiety. Fear of falling can lead seniors to curtail their physical activity, causing additional health problems and depression.

Together with the Arizona Center on Aging, iCAMP is conducting a pilot study on fall prevention with residents of Tucson’s Villa Hermosa Senior Living Center. The goal is to help elders improve balance and attention, thereby improving their dual tasking. Led by Michael Schwenk, iCAMP postdoctoral fellow and exercise scientist, the study combines balance training using wearable sensors developed by Najafi and UA biomedical engineer Gurtej Singh Grewal, with the Yoga meditation technique Kirtan Kriya. Dr. Dharma Singh Khalsa, director of the Tucson-based Alzheimer’s Research and Prevention Foundation, created the meditation program, and the foundation provided $21,000 in seed money for the study.

In addition to this study, iCAMP's National Institutes of Health-supported collaboration with Biosensics LLC led to the creation of ActivePERS. ActivePERS is an emergency response pendant with built-in fall detection that helps seniors live safely and independently in their own homes. It was recognized as one of the top 2013 technologies at the mHealth Summit conference.

Top picture: Bijan Najafi, right, director of iCAMP, and Gurtej Singh Grewal, UA research associate, explain how SmartSox are designed to help people with diabetes recognize precursors to foot ulcers.