It starts with passion.
That’s the best way to explain senior Justin Hollenbeck’s ambition. Even as a high school student, he was fascinated by the human body and how it moves.
During Hollenbeck’s freshman year at the University of Denver, the mechanical engineering major capitalized on that fascination, plunging into serious research at the Daniel Felix Ritchie School of Engineering and Computer Science’s Center for Orthopaedic Biomechanics. There, he worked alongside Associate Professor Peter Laz in the Probabilistic Mechanics Lab and Professor Paul Rullkoetter in the Computational Biomechanics Lab, learning how to apply engineering principles to the investigation of clinically relevant issues. The center offers undergraduate and graduate students a hands-on opportunity to develop and advance technologies that lead to improved outcomes for patients.
Hollenbeck’s hard work at the center paid off. In June, at the end of his junior year, he attended the American Society of Mechanical Engineering’s 2013 summer bioengineering conference in Sunriver, Ore., where he shared his work on “Statistical Shape and Alignment Modeling of the Lumbar Spine” in the student paper competition.
Hollenbeck’s paper grew out of a collaborative project involving not just Laz and Rullkoetter, but also Dr. Christopher Cain, an orthopedic surgeon at the Spine Center at University of Colorado Hospital. Cain shared some of his operating room challenges with the DU team, which set to work exploring them.
As Laz describes it, some of Cain’s most pressing challenges are presented by patients with disc injuries. “A lot of the surgeries he does are these total disc replacements,” Laz explains, noting that replacements often give the patient greater mobility than, say, a spinal fusion. But not every patient is a good candidate for the disc replacement.
“What Dr. Cain is interested in is to identify who are the right patients to get the implant and then where to place the implant,” Laz explains.
Enter Hollenbeck. Funded in part by DU’s Partners in Scholarship (PinS), a program that underwrites undergraduate research, his work tackled this question head on. “We pretty much developed a method to account for population variability within the lumbar spine,” he explains, noting that the work has ramifications not just for surgeons wanting to assess appropriate implant sizing and alignment, but also for implant designers and manufacturers. “With these quantifications, you can develop implants that can serve a larger population,” he says.
The ASME conference was packed with research- and innovation-minded engineers. Students got the chance to showcase their research at an exhibition space set aside especially for them. Conference attendees strolled through the displays and quizzed the students about their methodology and findings.
“I had to have my ‘A’ game for hours. I had no idea who was evaluating me,” Hollenbeck recalls, noting that hundreds of people stopped by his exhibit. “It was a stressful day, but I got to meet people from all over the world.”
Unfortunately, Hollenbeck’s busy schedule did not allow him to stay for the last day of the conference. However, a week later, he learned what he had missed by leaving early. That’s when a letter arrived from the ASME, congratulating him on receiving second place in the competition for undergraduate conference papers. Hollenbeck greeted the news at his home in Breckenridge, Colo., with an exuberant cheer. “It was unexpected,” he recalls. “I was very excited!”
As a conference presenter, Hollenbeck will see his paper published in the event’s proceedings. With this honor to his credit, he plans to continue his research into spinal implants. That means revisiting the paper with an eye toward publication elsewhere: “We’re trying to make it a little more robust, so we can submit it to the Journal of Biomechanics,” Hollenbeck says. In addition, he recently submitted some of his follow-up work to the annual meeting of the Orthopaedic Research Society.
–Nathan Wright contributed to this story