A team of engineering students set out to change the way doctors heal broken bones. It’s an invention that tackles the most common complaints about the common cast.
Jason Troutner, University of Illinois mechanical engineering student: “This is our flexible, silicone, lattice mold.”
It slips on like a piece of jewelry or a glove — a web-like system of interconnected tubes made from liquid silicone. But it’s not a fashion statement … it’s a cast!
Jason Troutner: “Those supports will immobilize the joint just like a typical cast. You can move some of these segments to avoid these bony protrusions so that we reduce the risk of pressure sores.”
That’s just one problem University of Illinois engineering students Jason Troutner, Ashley Moy and Justin Brooks set out to solve with their novel design.
Ashley Moy, University of Illinois bioengineering student: “We were prototyping with different materials. We started drawing with washable markers, ribbons and pipe cleaner just to try to find which ideas and designs would be good.”
It was the start of something exciting – an idea sparked by personal experience.
Jason Troutner: “I spent actually the first year and a half or so of my life with casts on both feet due to a bone deformity. I’ve spent so much time in this outdated technology and realized all the problems with it. First of all it starts to smell after a couple of weeks because you get the water and the bacteria and the sweat underneath it. As engineers we looked at it with an engineer’s skepticism and thought, ‘Is this really the best way to immobilize a joint?’”
Ashley Moy: “It was like, ‘Yes! This is it! This is what we’re going to do!”
That was a year ago. Since then the team has been hand-stitching and epoxying the waterproof design they plan on taking from prototype to mass production.
Ashley Moy: “Our idea is patent pending. The application process patent pending.”
Jason Troutner: “Unlike with the fiberglass casts, you can actually see the joint and make sure that it’s exactly where you want it to be.”
The flexible segments expand and contract to adapt to the size of the patient. Once they are in place, the tubes are filled with polyurethane plastic.
Jason Troutner: “That starts as a liquid. It’s two parts mixed together, and in about 20 minutes the liquid cures into a solid and makes this nice rigid structure that supports the bone. But it will leave the majority of the skin open to the air so the skin will be able to breathe. You’ll be able to wash the skin, and you don’t have to worry about stuff getting trapped underneath the cast.”
The lattice design allows for an added benefit — electrodes can be placed directly on the skin to stimulate muscles and bone that often atrophy in a traditional cast.
Justin Brooks, University of Illinois electrical engineering student: “Because the cast has all of these open spaces in it, we would be able to apply the vibration directly to the break site on the arm to speed up the muscle and bone growth.”
Jason Troutner: “We know these problems, and we know how to fix them. That’s what we’re trying to do with Cast21.”
Justin Brooks: “I don’t think I’ve had another school project where I’ve worked all night on something and been happy about it.”
The team will likely pull a few more all-nighters this summer. They’ve been accepted to the Zeroto510 program in Memphis, where they’ll work full-time on their design while navigating the regulatory process so they can eventually bring their invention to market – something they’d like to do in the next few years.
You can learn more about their design at www.cast21.com.