The new monitoring system records "acoustic emission data," or sound waves created by the tiny bone fissures. The same sorts of acoustic emissions are used to monitor the integrity of bridges, other structures and mechanical parts like helicopter turbine blades, said Ozan Akkus, an associate professor in Purdue University’s Weldon School of Biomedical Engineering. "When a microcrack occurs in a bone it generates sound waves similar to those created by earthquakes," Akkus said. "The goal is to create a wearable device that would alert the person when a stress fracture was imminent so that they could stop rigorous physical activity long enough for the bone to heal."
Researchers at Purdue have designed wearable acoustic emission sensors, which could be used to monitor the formation of these "microcracks" in bones that can lead to hairline stress fractures unless detected in time. The technology might help prevent serious fractures in racehorses that could cause lameness and lead to more serious catastrophic bone failure. Catastrophic injuries are rare in racehorses but still remain a major concern to horse owners and racing fans. This problem was highlighted by the recent tragedy involving this year’s Kentucky Derby second-place finisher Eight Belles. The 3-year-old filly broke both ankles as she was slowing down at the end of the race and had to be euthanized. Big Brown won both the Kentucky Derby and Preakness Stakes and is favored to win the Belmont Stakes on Saturday (June 7). Estimated losses attributed to bone fractures in thoroughbred or standardbred horses used in the horse racing industry exceed $10 million annually.
"While it is still in the early stages, this technology holds great promise for horses," said Adams, who specializes in equine lameness and surgery and is collaborating with Akkus in testing the system on horses. "These horses are running 40 miles an hour, and if there is a microfracture in the animal there is danger it will become a catastrophic failure. Currently, microfractures are not visible on an X-ray, and we need a viable way to detect tiny fractures before they become stress fractures or catastrophic fractures."
The Purdue Research Park is part of the Purdue Research Foundation, a private, nonprofit foundation created to assist Purdue University in the area of economic development. In addition to the Purdue Research Park in West Lafayette, the foundation has established or is currently constructing technology parks in other locations around Indiana including Merrillville, New Albany and Indianapolis.