New student-designed brace could aid drop foot patients
For years, Grand Junction eye doctor Tom Politzer has struggled with drop foot. Even a short walk could become frustratingly complicated.
But this year, three engineering students at Colorado Mesa University (CMU), including students earning their bachelor’s degrees through theĚýCMU-91´«Ă˝ Engineering Partnership Program, set out to make those steps a little easier during their senior capstone design course.
The CMU-91´«Ă˝ Engineering Partnership Program gives students the chance to earn a 91´«Ă˝ engineering degree entirely in Grand Junction.
The first two years of the program are taught by CMU faculty and the second two years are taught by 91´«Ă˝ faculty who live in Grand Junction. The partnership follows the same hands-on curriculum for civil engineering, mechanical engineering, or electrical and computer engineering at 91´«Ă˝, culminating in a year-long senior design project.
Working directly with Politzer, the team designed and tested a custom ankle foot orthoticĚý (AFO)—a wearable brace intended to better serve drop foot patients by improving stability, comfort and mobility.
“We did a lot of research on current AFOs in the market, including some of the ones that Politzer preferred. However, we found that many fell short in providing long-term durability and effectiveness,” said team member and mechanical engineering student Emma Coates. “Our project addresses these deficiencies by combining various brace designs into one better alternative.”
Drop foot, a neuromuscular condition caused by weakness or paralysis of the ankle dorsiflexor muscles, can make it difficult for patients to lift the front portion of their foot while walking. It’s often characterized by instability, changes in gait and an increased risk of tripping or falling.
According to a study in the National Center for Biotechnology, drop foot affects approximately 19 out of every 100,000 individuals in the United States. That includes Politzer, whose experience with the condition became the foundation for the team’s project.
A close-up look at the team's ankle brace designed for drop foot patients.
“Last year, Politzer sponsored a project in the senior design program using his background as an eye doctor to help people with impaired vision,” said group member mechanical engineering technology student Sami Mettler. “This year, he chose to continue that contact with the school by drawing upon his own struggles with drop foot.”
Several commercially available brace designs already exist for drop foot patients, offering support in a neutral, lifted position while walking to prevent the foot from dragging. Among them is the TurboMed XTERN, a brace Politzer has relied on for years.
Still, the group said current AFOs on the market were far from perfect.
“The TurboMed brace was durable, but Politzer said it could be uncomfortable and still allowed his foot to catch at times,” Coates said. “Our design aimed to improve both comfort and force output, giving him better stability while walking.”
Using technology atĚý, the team was able to create a brace prototype that improved comfort, breakage and provided more adequate dorsiflexion assistance. But that wasn’t the group’s only impactful outcome.
Team member and mechanical engineering student Izaak Siefken said that their design could help make AFO devices more accessible, as well.
The team's motion capture testing, conducted at CMU's Human Performance Laboratory.
“The cost of purchasing a durable, medical-grade brace is high. Every two years, patients can get a new one through insurance, but obviously things happen. They can get lost or even break,” said Siefken. “Our goal was to find a way to develop an effective device that was less expensive than the existing options.”
Beyond the brace itself, Siefken said the project also highlighted a major gap in how AFO performance is tested, evaluated and prescribed.
“There isn’t a system within the orthotic space where they can quantify if an AFO works well for someone. The only thing patients can do is try a brace and see how it feels,” Siefken said. “We did a lot of testing and gathered a lot of metrics in the Human Performance Lab. Maybe one day, doctors can use that data to set up a criteria of performance that can justify a brace choice.”
After months of research and development, the team unveiled its project at CMU’s Student Showcase on May 1. Along with the AFO prototype itself, they displayed design iterations and motion-capture data collected from the lab, allowing visitors to see how the brace affected Politzer’s walking in real-time.
Despite some struggles early on, the group said they were extremely proud of how their project turned out. But they believe the lessons they learned throughout their capstone journey extend far beyond their presentation at the showcase.
“We’ve had some internships in the past where you’re working on small projects and tasks for others,” Siefken said. “But in the senior design program, you are in charge of the entire project from start to finish. It’s on you to bear responsibility, take risks and develop a product that works.
“That’s exactly how it is in the workforce, and I think we are all prepared to succeed in that environment.”