For experienced healthcare providers, diagnosing concussions isn’t often too difficult but determining when a person has fully recovered from one can be more challenging. 

“All the tests we use to diagnose concussions, for the most part, don’t work to determine when you’re recovered from a concussion,” said Thomas Buckley, associate professor in the Department of Kinesiology and Applied Physiology (KAAP) within the University of Delaware’s College of Health Sciences. 

Recovery is often based on when people say they feel better, which triggers concussion protocols, a week-long progressive process before an athlete can return to play. However, some athletes lie to get back in the game quicker while others really do believe they feel better.  

“We don’t have the tech to find out if a headache is actually gone or not,” Buckley said. 

But evidence shows that in many cases people haven’t fully recovered from concussion, physiologically, before they return to play. 

“There are still some brain impairments and deficits present even when they say they’re fine and they go through this whole protocol,” said Buckley.

Those small deficits can be associated with athletes becoming two times as likely to suffer subsequent musculoskeletal injuries.  

“They get ankle sprains, muscle pulls, and the big one is torn ACLs — that’s surgery, there’s a lot of cost involved, you’ve lost a year of sports…it’s also lost school days, it’s lost workdays, it’s difficulty in quality of life,” Buckley said.

Every year in the United States, 250,000 anterior cruciate ligament (ACL) tears happen to people, translating into healthcare costs of more than $2 billion, according to the Centers for Disease Control. Women are up to eight times more likely to tear their ACLs than men because of the way they land after jumping.

Buckley said those subtle deficits reported in people who’ve experienced concussion can make the difference in subsequent injuries.  

“In sports, football, basketball, soccer, these are people running very fast, making decisions with speed, and so…if you go for a run, if you're off by a few milliseconds, nothing happens,” he said. “But if you're trying to dodge a human missile on the linebacker coming at you, a couple milliseconds can be a very big difference.” 

Most injuries following concussion don’t occur within the first few weeks of returning to play.

“The rate goes up over the course of a year, and so you’re actually more likely to get hurt in the six-to-12-month period than the zero to six-month period,” said Buckley. 

That indicates the impact of concussion is lasting far longer than protocols tend to deal tackle. 

Buckley has teamed up with data science professors Austin Brockmeier, assistant professor in the College of Engineering, and Wei Qian, associate professor of statistics in the College of Agriculture and Natural Resources, as well as UD’s Department of Athletics to develop an injury risk reduction model that will determine who is most at risk for additional injury following concussion. Their work is funded by a nearly $420,000 R21 grant from the National Institutes of Health.

The injury risk reduction model will be developed using sophisticated statistical analysis that will create a risk score based on commonly used assessments by clinicians. A top indicator for future injury is prior injury. 

“We really don’t know who’s at highest risk,” Buckley said. “Sex probably plays a role. Genetics probably plays a role. Prior injury history plays a role…we’re trying to pull a lot of these things in and using some of these machine-learning algorithms to sort through all the data and come up with a score — kind of like a red light, yellow light, green light — to identify who’s at risk of getting hurt again.” 

Cognitive tests that assess balance and ocular ability as well as motion capture systems which analyze how a person moves will also play a part in determining a person’s risk score. 

“It’s a highly valuable model, we would implement it immediately,” said Dan Watson, senior associate athletic director for UD Sport Performance. 

An athlete who’s then identified at the highest risk for subsequent injury could be targeted with specific injury reduction programs. 

“There are prevention programs out there that are quite effective at reducing the risk of ACL injury in females, but they're time consuming,” Buckley said. “They require someone working with you routinely over time. Athletes don't want to do it because they're never going to get hurt; it's always someone else that’s going to get hurt.” 

Watson called the collaboration between the injury risk research happening within the KAAP and athletics key.  

“One of the foundational pillars of UD Sport Performance is applying data-informed interventions that help each individual student-athlete consistently be the best version of themselves,” said Watson. “Dr. Buckley’s research in the injury risk reduction model following a concussion completely aligns and complements our approach.”

But could knowledge of the potential for a higher risk of injury impact an athlete psychologically, and in turn, impact play? 

“That’s a legitimate question,” said Watson. “We don’t necessarily say, ‘You’re at risk for tearing your ACL.’ We say: ‘You have this imbalance or this weakness, and you can do this corrective to help address that.’ 

“I think it’s how you frame it…because we want them to understand why we’re doing things. I think we would say: ‘This is part of the rehab to try to avoid injury post-concussion. This is what the science shows is going to help you get back out there and stay out there.’”

Buckley noted athletes are aware of injury risk.

“There’s potentially a concern — you don’t want to prime a person to be like, ‘Oh my God, I'm going to get hurt, I shouldn't do this,’ ” Buckley said. “At the same point, we view that as something minor compared to the actual risk of tearing your ACL, or breaking your leg, or even spraining your ankle.”

Implementing these kinds of individualized injury risk prevention programs will require educating athletes. 

“[Explaining to them], we can reduce your risk of tearing your ACL if you spend these 15-20 minutes, and because you're in a sport that there’s a number of ACL tears, and, and you've had a concussion, you're actually a pretty high risk,” said Buckley.  

Getting at-risk athletes into injury risk prevention programs now could also impact their quality of life long-term.

“We spend a lot of time with athletes thinking about them as athletes — not about them,” said Buckley. “These ankle sprains that happen in your 20s are not just about Wednesdays’ game against Hofstra.

“There’s a whole chain of — you sprain your ankle a bunch of times when you’re in high school or college, you’re at much higher risk of developing arthritis when you’re 40 or 50 years old, and that reduces how active you are; it’s harder to play with kids, and all of the diseases that occur with decreased physical activity.”