Purdue team gives baseball player new foot
LAFAYETTE, Ind. (AP) - Alex Morgan can't remember if he even liked baseball when his parents first enrolled him in T-ball.
The 13-year-old Lafayette resident and East Tipp Middle School student knows he loves it now.
Alex is an avid fans of the Cincinnati Reds and their star second baseman, Brandon Phillips. He plays the same position on his Harrison Youth Baseball Organization travel team next to his twin brother, Aaron, the shortstop.
Years ago, teammates and friends weren't aware of a significant difference between Alex and his blond-haired, blue-eyed twin. That changed around age 8 at a pool party for their Pinto League team.
"He came in a bathing suit and had to take his leg off and everybody was like, 'What's going on?' " said his mother, Carrie Morgan.
Alex Morgan was born without a fibular bone in his lower left leg. The condition - fibular hemimelia - affects about one in 40,000 births.
Rather than endure years of painful limb-lengthening surgeries that may or may not have helped - and which would have restricted Alex's physical activity - Jason and Carrie Morgan opted for amputation. Alex has worn a prosthetic since he was nine months old.
That didn't stop Alex from playing baseball - plus football, basketball, soccer and, for the first time this past winter, wrestling. Yet his prosthetic, inflexible and fragile, isn't ideal for a young multi-sport athlete.
A group of Purdue mechanical engineering students spent their school year trying to help Alex and others like him run and move more easily.
A joint effort between Purdue's Engineering Projects in Community Service (EPICS) program and students in mechanical engineering's senior design class culminated Thursday night. The six students presented Alex Morgan with a new ankle and foot design that offers greater range of motion and durability - and at a fraction of the cost of similar prosthetics already on the market.
Purdue mechanical engineering professor Eric Nauman called it the best senior design project he's seen. While the group is looking into patent options, it has also considered handing the design off to non-profit organizations who work with prosthetic patients.
"A lot of the projects are strictly concept, and at the end there isn't that satisfying giving it to anyone, or it's not going to go anywhere after you leave," said Rachel Berry, one of the senior design students. "This will actually make a difference."
Unless Alex Morgan is wearing shorts - his preferred outfit these days - one wouldn't assume he wears a prosthesis.
"I've been playing all the sports my brother has been playing and all my friends play," Alex said. "I just like being able to be with my friends and play with them on the same team and go to different places."
Alex and Aaron Morgan play on a travel baseball team with the son of another Purdue engineering professor, Thomas Talavage. That's how Nauman learned about Morgan, and how he came to suggest a prosthesis project to EPICS students Haley Smith, Jennie Boehm and Quinton Lasko.
That group met once a week and began developing a conceptual design. They first met Alex in late summer and began meeting with him regularly for various measurements and tests. They also went to one of his baseball games last summer to observe what an active young person needed from a prosthesis.
"It's not just running," Smith said. "It's stopping on a base, it's sliding, it's twisting. Having him come in and look at his motion, we're able to say, this is what he does. We need to figure out how we can put numbers to that and make sure it's not going to break when he does that motion."
Alex wears a rigid foot-and-ankle prosthesis bolted to a lower leg piece. He slips his own shortened leg into that piece and tightens everything into place with Velcro straps. Such prosthetics cost anywhere from $1,000 to $3,000. Out-of-pocket expenses for the Morgans, who both work for the Tippecanoe Sheriff's Department, are offset by insurance and help from Shriners International.
However, Alex's typical prosthetic allows only forward and back motion. It is also highly susceptible to breakage in the toe area at the ball of the foot.
According to the students, products currently on the market that provide greater range of motion, including side-to-side, range from $10,000 to $15,000. The EPICS students conceived of a ball-and-socket joint that better replicates the motion range of a real ankle, on a foot with a toe hinge, made of a more durable material.
Oh, and it all had to be done at a significantly lower price.
Three people meeting one day a week weren't going to accomplish that by graduation. So senior design students Berry, Ally Gleason and Sami Labban joined the group, which began working on the project daily.
"We have some of the most ingenious students here," said Nauman, "and you kind of let them go on something like this and they come up with just amazing solutions."
Playing football in the backyard one day, Alex planted his left leg to give him leverage to kick with his right.
He heard a crack. Alex looked down at a leg with no foot. His prosthetic had snapped off at the ankle.
"There's not an emergency room for that," Carrie Morgan said. "So he didn't have a leg.
"It happened on a weekend and we couldn't get in (to the prosthetist) for another week. We duct-taped it and he walked carefully."
Alex's prosthetics have broken at least three times. With no tendons or muscles attached to a prosthetic, the limb is essentially dead weight. According to the Purdue students, doctors say limbs that are too heavy is the No. 1 complaint of prosthetic users.
The Purdue students learned that the hard way about halfway through their project.
Their first design consisted of a carbon fiber foot covered in plastic. That product satisfied the need for a lightweight limb with the desired flexibility.
There was only one problem. The design needed to withstand about five times the patient's body weight - in the case of 100-pound Alex, that's 500 pounds of force - to hold up against the running and jumping of a young athlete.
When it came time to test the design in late February, concern turned into panic. The steel base plate in the ankle crushed through the heel at only 30 pounds of force. The students needed something stronger, but they couldn't add much weight. They also had to use components in scale with the size of Alex's other foot.
"We're used to over-engineering everything," Gleason said. " 'Oh, it needs to be stronger? Let's just make it bigger or let's make it out of something that's stronger.' Well, if it's stronger, it's probably heavier.
"We have to make this tiny little piece and it has to hold 500 pounds, and how are we going to do that?"
Previously the students used state-of-the-art 3D printing technology to create their carbon fiber design. Now they turned to a more old-school approach: aluminum. While heavier than carbon fiber, aluminum is light enough to limit the wearer's discomfort yet still holds up to the necessary weight constraints.
The students designed an entire manufacturing process and became regulars in the Purdue machine shop over the next six weeks. They were novices when they first walked in. A few weeks ago, other students started asking them if they were the teaching assistants.
On Thursday night, the team presented Morgan with an aluminum foot protected by a plastic shell and connected at the ankle with a ball and socket. He took his tentative first steps with the foot in the EPICS lab at Armstrong Hall, replicating his pitching motion. Where Alex's heel previously hit the ground with no give, he now had a more natural bend with his plant foot.
According to Boehm, the entire manufacturing cost of the project, including labor, was $633. Even with the standard markup for similar medical devices (about four times cost, according to the team), the design represents a dramatically cheaper alternative to prosthetics with similar mobility.
Alex Morgan can't comfortably wear the design yet. The foot given to him was attached to an older prosthetic leg that doesn't fit well anymore. The Morgans hope the foot can be attached to a new leg, which he could receive later this summer.
Alex is old enough to realize he's not the only one who could benefit from this project.
"I like that maybe people will be able to get them for cheaper," Alex said. "I was basically the guinea pig."
The students say the mold for their design can be configured for 40 different sizes of either right or left feet and for any weight category.
Everyone from the group is graduating except Lasko, a junior who plans to carry the project forward into his senior year. The goal is to eventually merge this design with another EPICS project that endeavors to make prosthetics more active. Sensory technology could help motorize the prosthesis, allowing for improved gait when running and other improvements.
"This whole next year we're going to work on different ways to implement that actuation with this mechanical design," Lasko said. "We want to give them that advantage to have that force output from the foot to get a little more out of it."
The students say the manufacturing cost should continue to plummet as technology advances. Once 3D printing of carbon fibers can handle the weight requirements, total cost of materials and labor could top out around $100.
As of Thursday night, the students hadn't yet received their project's grade.
Watching Alex Morgan strap on their design, raise an imaginary bat above his shoulders and take a swing provided its own satisfaction.
"A lot of the projects at the end of the semester are just scrapped and put in a locker for other projects to use," Labban said. "He just walked out the door with ours."
___
Source: (Lafayette) Journal-Courier, http://on.jconline.com/1sbdyLM
___
Information from: Journal and Courier, http://www.jconline.com