ACL injuries are on the rise. How do we prevent them?

ACL injures are on the rise in all teen athletes, but the increase is higher among girls. High Point University is researching new movement patters to prevent ACL injuries as well as more effective rehabilitation.

HIGH POINT—It was a soccer game just like any other soccer game for 13-year-old Kylie Peters, who played for the Piedmont Triad Football Club. Until…. “I tried to step with the ball and then my knee gave out,” said Peters. “I heard a pop and it hurt like crazy.”

“She just went down and you could tell it was a lot of force she put on that knee,” remembers Jessica Peters, Kylie’s mom. “It wasn’t something she hadn’t done before but you could tell she was hurt. Her Dad had to be called onto the field to take her off and we just knew it was serious from that time.”

Kylie had torn her anterior cruciate ligament, or ACL. You hear about the injury with professional athletes but it’s common in amateur sports as well. And the rate of ACL injuries in female athletes is two to eight times greater than in male athletes. Kylie knows the statistics. But now, six months after surgery to repair the torn ACL, she’s involved in a study at High Point University’s biomechanics lab.

“I just wanted it to be a dislocated kneecap but it wasn’t,” said Kylie and she runs on a treadmill. “I was really sad, because I really wanted to play soccer, but I’m feeling good and I’m getting stronger. I’ll be back on the field soon.”

“Our main goal is to identify these risky movement patterns and then train them to change the way they move.” explained Jeff Taylor, Ph.D., associate professor in the Department of Physical Therapy at High Point University. "Some of that might just be making certain muscles stronger, but it’s probably more than that. It’s cueing the girls into their faulty movement patterns and teaching them the right way to move.“

The training program has three parts. The first is simply building strength. The second is strengthening the core. Even though ACL injuries involve the ligaments around the knee, much of the strength that is needed for optimal movement comes from the core. Finally, the most important part of the program is technique training. That involves jumping and cutting and making knees are over toes, bending knees and softer landings. Once the proper technique is taught, then it’s a matter of making sure the athletes remembers and practices what she is taught.

It’s easy to see the techniques while watching Kylie and the other girls in the program go through drills. There are jumping drills, dribbling drills with soccer balls, and running drills that involve cutting, or quickly changing directions.

“We think most of the benefits are going to come from teaching athletes them how to move,” said Taylor. In addition to the instructional drills, the program also uses innovative biofeedback. Sensors are attached to the athletes, who them perform the drills in front of a television screen. The wearable sensors combine with computer programs to turn the athletes into skeletons. That allows researchers and the athletes themselves to analyze their movement patterns in real time.

Professor Taylor shows a video of the initial screening of one of the athletes in the program. When she landed after jumping, her knees bent inward at a roughly 40-degree angle.

“This really jumped out at us,” explained Taylor as he pointed to the knees. “As soon as she starts to absorb force in her lower extremities, you can see those knees coming in and almost touching they are so close. It’s that valgus angle that we really look at, that produces a lot of force at the ACL.”

Athletes say they like the immediate feedback, thought they admit it is a weird feeling to see your movement in real time. “Before this I didn’t think about it,” said Ella Frey, a soccer player who didn’t injure her ACL but hopes the program will prevent the injury in the future. “I didn’t think it was an issue but now I know I need to concentrate on it if I want to keep playing.”

Researchers hope the combination of drills and evaluations will identify risky movement patterns and then help them teach the athletes safer ways to move. The study is also looking at more effective and efficient rehabilitation methods for ACL’s that are repaired.

“We want to train appropriate movement patterns and effective movement patters,” said Yum Nguyen, Ph.D., associate professor in the Department of Athletic Training at High Point University. “Because while they might have the strength to move, they need to be able to use it during dynamic activity."

Nguyen emphasizes their work is not just making athletes stronger or repeating drills to help with what is called “muscle memory.”

“Our goal in this study is to be able to identify those at greatest risk of ACL injury and intervene and reduce that risk,” adds Nguyen. “We want to create something these athletes will use, that will keep them interested and be beneficial to them. Because if you create an intervention program and nobody uses it, it doesn’t work.”