The winner of the 48th annual Alpha Omega Alpha Medical Student Research Forum at SLU, Murtha presented his research that combines two recent advances in design to improve new hip implants to SLU School of Medicine students and faculty. Murtha was chosen as the winner from a group of six presenters.

"I always wanted to learn more about hip replacements," said the Cedar Rapids, Iowa resident Murtha, who graduated from SLU with an undergraduate degree in biology. "I received great exposure through this project as we went about designing techniques for the model."

The biomechanical study found that using a thinner plastic (polyethylene) liner to accommodate a larger femoral head, which replaces the highest part of the bone in the thigh, did not increase the risk of fracturing the liner. Prior research has shown that using larger femoral heads helps to reduce dislocation, a common complication of this procedure.

Traditionally, hip dislocation and degeneration of bone tissue from the liner's wear debris are the two complications of hip replacements that require more operations. These have been addressed by two biomechanical designs -- increasing the size of the femoral head that prevents the hip from getting dislocated and using newer types of wear-resistant polyethylene to avoid bone degeneration. In this study, Murtha worked with his collaborators to ensure that using both methods simultaneously would not compromise the structural design of the implant.

"We found that larger diameter heads can be used with this newer wear-resistant polyethylene in hip replacement surgeries without compromising the liner's locking mechanism," Murtha said, emphasizing that this is a promising modification in design to improve ball and socket systems currently in use.

"There are still limitations to this study as we have just looked at one liner design. However, our data supports developing current technologies to reduce complications." The panel of judges at the research forum was very impressed with Murtha's in-depth knowledge of the study.

"Andrew was really involved in all stages of this project. He knew the ins and outs of it, how the hardware will be tested and what the questions were. It's nice to see a student carry a project all the way," said Michael Rauchman, M.D., associate professor of internal medicine at SLU and one of the judges at the research forum. "This was a basic, bio-mechanical engineering study that had clear translation and application in terms of what kinds of hardware would be used to reduce complications in a hip replacement without causing any adverse effects."

Murtha will present his work at the 54th Annual National Student Research Forum in Galveston, Texas in April.