Dr. Evan Liu advocates for “back to basics” as fitness trends meet physical therapy
On March 11, the Oregon Chapter of the American Physical Therapy Association will host its annual physical therapy conference in Portland—and Dr. Liu, an Assistant Professor at Pacific and a Board Certified Orthopedic Clinical Specialist—is on the docket to present a new idea that stands on old wisdom.
His presentation, “The Not-So-New, Missing Links in ACL-R and Return to Sport Considerations,” advocates for a return to tied-and-true methods of physical therapy for athletes that prioritizes the quality of their recovery over the speed of their return to the sport.
Dr. Liu explains that when an athlete tears their anterior cruciate ligament (ACL) in their knee, they have to undergo a surgery known as an ACL-R to fix that torn ligament. However, as he points out in his presentation, Dr. Liu and his colleague and Board Certified Specialist in Sports, Dr. Logan Walters, want to recenter focus from the surgery to the rehabilitation process.
According to a 2014 study conducted by Dr. Mark V. Paterno, 20 to 25 percent of athletes who tear their ACL will retear it or tear the other ACL within two years of returning to their respective sport.
“You see on Instagram and TikTok all these crazy new exercises and all that stuff, but a lot of the time, we forget about the foundation of rehab,” explained Dr. Liu. “And so that’s where part of the conversation that we’re having is going back to the fundamentals and making sure we’re checking off the foundation before we move on to the heavy advanced stuff.”
Dr. Liu calls his presentation “Not So New” because his point is not to reinvent the wheel (or the knee, as it were) but to remind physical therapists of the foundation blocks that are at risk of being forgotten in the quest for improved ACL rehabilitation.
One of the foundational blocks Dr. Liu will address is the integration of qualitative measures into testing during rehabilitation. To explain this idea, he discussed one of the quantitative measures physical therapists use when determining an athlete’s return to sport: timelines.
When athletes are in the rehabilitation process, the physical therapist creates a timeline to show the athlete when they will be cleared to do activities such as running, jumping, and cutting. While he sees the reasoning and logic behind using timelines, Dr. Liu also sees a concern.
“If they’re not qualitatively ready to do it, let’s say their quad isn’t strong enough, their hopping doesn’t look good, their jumping doesn’t look good, then the likelihood of them being ready is lower,” explained Dr. Liu.
While timelines can give athletes an understanding of the length of their recovery process, having their recovery based primarily on time doesn’t consider how the athlete is progressing. Dr. Liu advocates a criterion-based assessment of an athlete’s ACL recovery: Rather than telling the athlete that they’ll be able to run in three months, tell them they must meet specific criteria before returning to their sport.
While the solution of combining qualitative and quantitative measures sounds simple, its implementation is far more complicated than one might expect. Dr. Liu mentioned that choosing the appropriate criteria to evaluate an athlete’s progress is difficult. In addition, taking away that quantitative timeline can cause problems for certain athletes wanting to return to the field as soon as possible. The more time they spend not knowing when they’ll be able to return and practice, their anxiety and frustration builds. Worse yet, they lose confidence in their abilities and performance.
Dr. Liu acknowledges that utilizing qualitative measures like criterion-based assessment has its faults. Even so, he believes that using qualitative measures along with quantitative ones is necessary to reduce athletes’ ACL retear rates.
“The thing is the environment that they’re playing in is very random,” said Dr. Liu. “Anything can happen. A ball goes by you. Someone pushes you from behind. The grass is slippery, your cleats come off, or whatever it is.”
Dr. Liu believes that if physical therapists want to ensure athletes safely return to sports from ACL injuries, they must incorporate some of the randomness that comes with playing sports. He suggests adding variation to tasks. An example he gives is a drill in which the recovering athlete has to catch this triangle toy they throw that has different colors painted on each end. When the physical therapist throws the triangle, they call out the color, and the athlete has to find the color on the triangle and catch it before it touches the ground.
With his presentation at the conference, Dr. Liu hopes to remind the scientific and sports communities about the foundation blocks of ACL rehabilitation and propose a multi-system approach to recovery. He hopes that his ideas and approach will give athletes the confidence to safely return to their sports while reducing ACL retear rates. — Kaleb Makimoto