Past and Present Biomedical Engineering Students Help Discover Better Hip Replacement Designs

Thursday, January 14, 2016
 Hipster Story

Shaping Up: Students used the Orthopaedic Biomedical Engineering Laboratory, located in Myers Hall, to determine the optimal shape for hip replacements provided to people whose original hip replacements have failed.

Rose-Hulman students have learned that their biomedical engineering skills can improve people's lives by helping medical device makers develop innovative products for those struggling with debilitating hip problems.

In two different national studies, students used the on-campus Orthopaedic Biomedical Engineering Laboratory to evaluate hip stem designs used when an original hip replacement has failed, and discover the optimal length for hip replacement stems.

"We conducted a study across a wide range of stem shape options to determine what combination of factors lead to the most stable implant," says Scott Small, engineering director for the Joint Replacement Surgeons of Indiana (JRSI) Research Foundation of Mooresville, Indiana. The Orthopaedic Biomedical Engineering Laboratory, located in John T. Myers Hall, is a collaboration between JRSI and Rose-Hulman.

A new hip stem, introduced by Exactech, Inc. of Gainesville, Florida, based on the students' work, has been approved by the federal government's Food and Drug Administration, and is in the pilot-launch phase with doctors in Indiana and New York.

"Our work with Rose-Hulman was critical in the development of this product, which is now helping patients throughout the world. The RHIT team was thorough, insightful, timely and very professional," says Jeff Pierson, an orthopaedic surgeon with the Franciscan Medical Group in Indianapolis and the JRSI Research Foundation.

"I learned the fundamentals of how the total hip replacement works," remarks Ryan Seale, a 2015 biomedical engineering alumnus, who worked on the project and is now a clinical research specialist for Zimmer Biomet, a medical device manufacturer in Warsaw, Indiana. "It also showed me that what I was learning matters and can make a difference in people's lives."

Zimmer Biomet used recommendations from another student team to introduce a new hip stem that is 36 percent shorter than the original design. This will enable surgeons to make smaller incisions, causing less soft tissue damage, while maintaining stability and load distribution within the bone.

Key to this project was that the students developed a novel approach to image analysis techniques to analyze the motion and stability of an implanted stem, according to Small.

"This method enabled us to generate extremely precise stability measurements in a much simpler and efficient manner than has been done in previous studies," he says.

The students presented their findings at professional conferences in Las Vegas and Sonoma, California. They have also submitted their research to a professional journal for peer review.

"I gained hands-on experience, including the design, test, and validation components of research," says Sarah Hensley, a 2015 biomedical engineering alumna now a graduate student at the University of Colorado in Denver. "Most important, though, was gaining confidence in my engineering skills, and realizing that this is the type of research I wanted to do after completing my Rose-Hulman degree."