How Do You Recover from an ACL Injury?

An injured anterior cruciate ligament (ACL) is a diagnosis that puts fear into athletes. This devastating injury inhibits a range of motions with the knee, and can put athletes out of commission for months. They’re often career threatening.

Senior kinesiology and health science major Chaciydah Heffner joins classmate Ana Gabriela Galvao, a mechanical engineering with a biomedical concentration major, in interdisciplinary research to prevent such devastating injuries. They looked at how an environment affects the physical activities commonly used to gauge activity for ACL injury recovery, known as return-to-sports testing.

“Once the athlete actually goes to play, (they’re) most likely going to be playing in various conditions,” said Galvao. “And we don’t really know how that ligament or those muscles are reacting to that.”

With so many potential environmental factors, Galvao said they chose to focus on temperature. “I really like the idea of looking at the data that we collect and understanding better how the muscle and how the tissue is reacting and the different properties and how the mechanical properties are changing with fatigue, with temperature, between men and women, right and left leg.”

Subjects performed the cluster tests under controlled conditions at 68 F: single-leg vertical jump, single-leg hop test for distance, and the single-leg lateral (side) hop. Using a device called the Myoton Pro, they assessed muscle properties like tone, elasticity and stiffness.

Later, the subjects would repeat the same tests in a chilly 46.4 F environment

Early results were surprising; there was little indication a cold environment negatively impacted performance. Galvao and Heffner found the opposite was true: performance increased in the cold.

Another unexpected finding was no significant statistical difference in muscle property or performance between the two legs, even if one is declared the dominant by the study subject.

“One of our subjects even mentioned that she was a dancer and she thought that her right leg was for sure stronger than her left leg,” Galvao said.

Their next step is to expand the number of test subjects and create the third test environment at 80.6 F. Galvao and Heffner plan to present the full study in October and eventually publish the research in a peer-reviewed journal. Already the project earned the Interdisciplinary Undergraduate Research and Creative Projects Summer Fellowship.

“It was difficult in the beginning, I feel like we speak two different languages,” said Heffner about coming from two unique disciplines. “… (However) we both communicated (well) with each other.”

The two researchers hope to bring this project into their future careers. Galvao is exploring grad school, and will use this experience as a stepping stone toward a doctorate. “Having the research is like an extra class in which I am learning so much more about the area that I actually want to go in within engineering,” she said.

Heffner plans a career in physical therapy and is excited about using the research results actively in her future work.

“I think this study really hits home for me because I can use this in a clinical aspect throughout my career,” she said. “I would actually be helping people and helping myself at the same time.”

- Mel Huang