David Armstrong, DPM, MD, PhD, a professor of surgery at the University of Southern California (USC), Los Angeles, Keck School of Medicine, and Charles Liu, MD, PhD, a professor of clinical neurological surgery and director of USC’s Neurorestoration Center, have collaborated on the development of a smart insole. The technology has implications for the reduction of amputations resulting from diabetic foot ulcers.
Both were already studying how much information a person takes in through the nerves of the feet; how to preserve, repair, or replace that information system; and how nerve damage can affect a patient’s mobility. Armstrong, who is also the founder and co-director of the Southwestern Academic Limb Salvage Alliance, which aims to reduce diabetes-related amputations, is interested in metabolic health, mobility, and neuropathy, Liu noted.
“As a neurosurgeon, I’m interested in lower-extremity function and metabolic health, too,” he said. “In my work, I think about how to restore mobility to patients who can’t feel their legs. It’s a similar problem to diabetic foot ulcers.”
While looking for a project on which to collaborate, the surgeons came across a Canadian security company that was working with the idea of capturing pressure signatures — the way weight is distributed across people’s feet as they walk — which are as distinctive as fingerprints. The surgeons realized that pressure signatures could be a way to spot changes in a person’s gait early on, which can be a warning sign of a more serious problem. With their shared interest in wearable technology, Armstrong and Liu steered the company toward developing a smart insole. The device will flag changes in a patient’s gait, activity level, and balance, as well as monitor for the localized temperature increase that can reveal a building infection before the human eye can spot it. Further, Armstrong and Liu expanded the functionality of the insole to have it reward patients for increasing their activity or losing weight, make nutritional recommendations, or discreetly remind a patient to get his or her daily walk in. Their work has the potential to give patients a sense of greater contact with their care team while reducing the need for in-person office visits.
The insole tied for first place for the Global People’s Choice Award in this year’s Diabetes Innovation Challenge run by T1D Exchange.