Why do those who tear their ACL have a hard time returning to sport?
Kinesiology scholar Shelby Baez is being recognized for her outstanding dissertation on the topic by the Association for Applied Sport Psychology (AASP).
“Athletes and other individuals who tear their anterior cruciate ligament (ACL) know they’re going to be out of activity for a long time. We recommend most athletes don’t return to sport for nine months, but it can take up to two years before full physical function is restored,” Baez said.
The ACL serves as a stabilizer in the knee and helps perform tasks like changing directions. That’s why many athletes who play sports such as football or soccer, where they often need to change directions quickly, can have the injury.
Defining (and fighting) fear
The injury is damaging physically, but it also plays a significant toll mentally, Baez’s research found. Her dissertation, “Injury-Related Fear in Patients after Anterior Cruciate Ligament Reconstruction,” was comprised of three distinct studies.
The first found that psychological factors—specifically injury-related fear and self-efficacy (or belief in our own abilities)—factored more heavily than functional capacity with return to sport and physical activity. In other words, the patients didn’t believe they could accomplish the physical tasks, so they didn’t.
It has something to do with life after injury, Baez said.
“Once you damage the joints, you’re more likely to have knee problems further down the road, like osteoarthritis,” she explained. “Further, about 30 percent of patients will sustain a reinjury. So, the initial injury is scary. It can be life-altering.”
This may be due, in part, to what Baez found in the second study: notable brain changes in those who had an ACL reconstruction compared to healthy individuals. Comparatively, those who had been previously injured had more active emotional regulation centers in the brain.
Post-ACL injury, individuals had a tough time suppressing the brain’s “default mode network,” or areas of the brain active when not thinking about a task. These areas of the brain are supposed to be less active when doing a goal-oriented task, like climbing a set of stairs, but patients who had had ACL reconstruction could not get their brain to quiet down. Instead, the fear was constantly there.
For the third study, Baez then examined if in vivo exposure therapy could help individuals better respond to the injury-related fear. This therapy, in which someone faces their feared object, situation or task in real life, helped—but only a little.
Baez found the therapy helped people improve in specific tasks—like climbing stairs, or jumping—but the overall fear they had did not improve.
Baez, who joined the Department of Kinesiology as an assistant professor in fall 2019, hopes the research will improve how coaches, rehabilitation specialists and more respond to people who have had an ACL injury.
“The culture of sport is a culture of risk. People are praised for ‘playing through the pain.’ If we can conduct more studies like this to say: ‘This isn’t just subjective. The patient isn’t just being weak or complaining, they are presenting with objective changes in their brain,’ it will help.”
Baez hopes things like mindfulness and meditation can be next steps—and that is where her research is turning. She wants to explore if these tactics can help individuals acknowledge the fear, but then let it go and, ideally, start to heal their brain along with their body.
Baez, and other Spartans, will officially be recognized for their work and careers in October during AASP’s annual conference. Joining Baez in the recognitions will be Kylee Ault, who received the Masters Thesis Award, and Dan Gould, who will receive the Distinguished Professional Practice Award.