Wednesday, February 26, 2014
In sports, a big hit to the head is often called getting your “bell rung.” The resulting injury could be a concussion, sidelining the player. But for how long? And when is it safe to get back into the game?
A new study by Cincinnati Children’s Hospital Medical Center highlights innovative ways to analyze post-concussion impairments. And it’s showing promise for being more reliable and sensitive than commonly used methods of predicting when a player has recovered.
“We believe we have found a better way to tell when young players are safe to return to action,” says the senior author of the study, Catherine Quatman-Yates, PhD, and physical therapist at Cincinnati Children’s.
The study focuses on young athletes between the ages of 10 and 16. And it uses a method called postural sway complexity to determine if symptoms from a concussion are lingering.
To test postural sway complexity, an athlete stands on a force platform that measures motion of the body in space (here is an example: http://www.amti.biz/fps-guide.aspx). In Dr. Quatman-Yates’ study, each athlete was asked to stand still with feet together for two minutes, one time with eyes open, the other with eyes shut. Responses were measured and analyzed.
Swaying while you stand is normal. But the patterns in a person’s sway can be an indicator of whether an athlete is still in an impaired state following a concussion. “This is a test that’s so subtle you can’t visually detect it. That’s why we put them on the platform,” she says.
Patterns of sway outside the norm – too little or too much randomness or regularity in the patterns – can indicate the concussion injury hasn’t healed. The surprise in the study is that athletes who had suffered a concussion demonstrated less sway and more regularity in their sway patterns than their healthy counterparts. In other words, they swayed less overall and were more robot-like in their sway whereas the healthy participants swayed more but were more random and more “natural” within their sway patterns.
Dr. Quatman-Yates believes less sway occurs because of how the brain tells the body to react to its surroundings. “It’s part of the subconscious,” she says. “We believe it’s the body’s attempt to hunker down because the brain is not ready to process the information around it; therefore, it controls the body more tightly.”
The study indicates that postural sway patterns over time can indicate whether a young athlete continues to have post-concussion dysfunction. In fact, indications are that it may do a better job of detecting continuing concussion impairments for youth than does the most popularly used concussion screening method called the Balance Error Scoring System (BESS).
BESS relies heavily on observation whereas postural sway relies more on technological data. Often times, BESS testing can indicate a child or adolescent does not have postural control impairments and may be ready to play three or four days after a concussion occurs while the postural sway complexity test may indicate that underlying impairments are still present.
As a researcher for Cincinnati Children’s, Dr. Quatman-Yates is interested in how concussions affect young athletes – teens and preteens. These players are at a stage of life where their brains are still developing, meaning the impact of a concussion could hamper development, especially if the athlete experiences a subsequent concussion by going back to play too soon.
One of the things that makes the study so promising is its practical application. It’s a noninvasive way to collect, analyze and interpret data in real-time in less than five minutes in most clinical environments.
The study followed 20 concussion patients (13 boys, seven girls) and compared their postural sway results with 20 nonconcussed athletes of similar age (10–16). Dr. Quatman-Yates acknowledges that the findings from this study are still preliminary due to the relatively small number of patients that were included. She says the findings warrant more study with the next step expanding the research to involve 750 healthy athletes to determine a better estimate of what healthy postural sway patterns look like across the span of childhood and adolescence.
During a year’s time, approximately 800,000 pediatric sports and recreation-related head injuries are treated in U.S. emergency departments. After a concussion occurs, a child’s brain remains vulnerable for an unknown period of time. If a child returns to play during this vulnerable period, they could be at great risk for further damage to their brains and even death. Dr. Quatman-Yates’ goal is to ensure that these young athletes return to play as soon as possible, but only when their brains have fully recovered from the injury. And she believes postural-sway complexity testing could be a step in the right direction for helping determine when the brain is fully recovered.
“No one is really using this technique to determine readiness to get back in the game following a concussion. They tend to use observational tools. The concern is there could be long-term damage if they return to the game too soon. That’s one of the things this study tells us – a child may need more time to heal even when visible balance problems are no longer present. Otherwise, we risk putting kids back out there in an impaired state,” she says.
Dr. Quatman-Yates’ study is being hailed by her peers. At this year’s annual meeting of the American Physical Therapy Association’s Orthopaedic Section, the study was given an Award of Excellence.
Cincinnati Children’s Hospital Medical Center ranks third in the nation among all Honor Roll hospitals in U.S. News and World Report’s 2013 Best Children’s Hospitals ranking. It is ranked #1 for cancer and in the top 10 for nine of 10 pediatric specialties. Cincinnati Children’s, a non-profit organization, is one of the top three recipients of pediatric research grants from the National Institutes of Health, and a research and teaching affiliate of the University of Cincinnati College of Medicine. The medical center is internationally recognized for improving child health and transforming delivery of care through fully integrated, globally recognized research, education and innovation. Additional information can be found at www.cincinnatichildrens.org. Connect on the Cincinnati Children’s blog, via Facebook and on Twitter.