by Dewayne Wright
In Steven Anton’s vision of the future, knee implants will not only help patients walk better, the implants will be able to tell physicians how well they are working. He has received a $417,000 grant from the National Institutes of Health to support this research.
Anton, working with noted orthopedic surgeon R. Michael Meneghini of Indianapolis, is researching the use of piezoelectric materials embedded in artificial joints in order to sense knee forces and to ultimately increase the success of joint replacement surgeries and extend the life of the joint in order to reduce future surgeries.
“By embedding piezos into the implants,” Anton said, “not only can the joints sense stresses being put on the joint during surgery, they can harvest electricity from the joint’s motion and continue to power the sensors for measurement of forces for the life of the implant. Ten to 20 years ago, this was not feasible; now it is.”
Anton explains that one post-operative benefit is that the sensors would help with physical therapy by making it data driven.
“Your therapist can see what forces are affecting the joint,” Anton said, instead of relying on the patient’s description of how the action feels.
A long-term benefit would be to correlate surgical procedures and materials to successful patient outcomes in order to determine the ideal surgical procedures and implant design.
“Hip and knee replacements are becoming more common,” Anton said. “Younger people are getting them replaced. Currently, the life expectancy of a knee or hip joint is 10 years. The ultimate question is can we improve the life of an implant and the patient’s satisfaction.”
According to Anton, more than 100,000 patients are not satisfied with their quality of life after receiving an implant, which accounts for up to 20 percent of joint-replacement surgeries.
The first stage of the research is confirming what happens when the piezos are installed on the implants, obtaining much-needed data to prove feasibility. From there, the process calls for partnering with joint manufacturers and returning to the NIH for clinical studies.
“We’ve been working on this for three years,” Anton said. “It’s a very continual process, but we have a path to get there.”
Anton’s interest in engineering came from following in the footsteps of his father, who started on the assembly line at General Motors and worked for the automotive giant while earning his degree in industrial engineering.
“What sealed the deal for me was my aptitude in math and science,” said Anton, an assistant professor of mechanical engineering. “It came naturally. Engineering was a good fit. I was always hands-on, and engineering was a practical field.”
From his start, Anton has built a research agenda in smart materials that has led to his current work to help improve the quality of life of people with artificial joints.
Anton’s work with piezos has led to two distinctions: being the recipient of a Young Investigator Award from the Air Force Office of Scientific Research, and authoring an article that has been cited more than 1,500 times.
The Air Force award was his first successful grant proposal, and involves developing real-time structural health monitoring systems for systems operating in highly dynamic environments – such as high-velocity impacts, explosions or shocks –in order to identify changes to the structures on a microsecond to millisecond timescale.
Anton directs Tech’s Dynamic and Smart Systems Laboratory. He joined the mechanical engineering faculty in 2013. Prior to joining Tech, he was a postdoctoral researcher at Los Alamos National Laboratory.