Does Playing Soccer Change the Brain?
November 26, 2012
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Cooper City football player Tyler Sabine took a brutal hit in a game early this season. The sophomore was throwing up just before halftime. His coaches knew it was time to pull the linebacker from the game.
Two days later, Sabine was diagnosed with a concussion.
That diagnosis kicked into place new guidelines passed by the Florida Legislature eight months ago, establishing strict procedures to allow concussed athletes, such as Sabine, back on the field.
Sabine was sidelined for more than two weeks before doctors cleared him to begin the gradual four-step return-to-play protocol now mandated by the Florida High School Athletic Association.
“Our trainers were amazing once they realized there was an issue,” said April Bourassa, Sabine’smother. “It was scary. It’s a brain injury, and it’s not like you have another one of those. But they’ve really made it to where now, you’re more informed and I love that. Everyone was very thorough. I felt like my son was being taken care of and informed.”
High school coaches and parents are being more hands-on about concussion awareness. Injured athletes are being evaluated by physicians, and sitting out as long as needed. Once medical clearance is given for them to return, athletic trainers are helping those athletes follow state guidelines that gradually manage a safe return to play.
“This is something that had to be dealt with,” said Archbishop McCarthy coach Byron Walker, who has seen one of his players, running back Nick Bost, sidelined with a concussion this season. “It takes it out of the hands of people who have an interest and puts it in the hands of professionals. It’s just going to be safe for the kids in the end.”
Bost, who was injured during spring practice, only recently returned to action after dealing with post-concussion syndrome months after his concussion.
“I knew it had to be done,” Bost said. “It may have been a mild concussion, but I wanted to be cautious and because I was still having symptoms, I held myself out. And my coaches were cool about it. They understood.”
Returning to action
The new law requires that if an athletic trainer or coach suspects an athlete has suffered a concussion, the athlete must be removed from play. And once an athlete has been diagnosed with a concussion, he or she cannot return to play until medically cleared by a physician.
Once that clearance is given, state policy dictates an athletic trainer supervises a four-step return-to-play protocol in which athletes see their activity level increase daily. If at any point in the process, an athlete exhibits concussion symptoms such as dizziness or sensitivity to light, they must wait at least 24 hours before attempting that level of activity again.
Youth football leagues across South Florida also are working to keep the youngest football players safe. Ross Sinel, president of the American Youth Football League, which includes teams from Broward, Palm Beach and Miami-Dade counties, said educating coaches and parents has been a major part of the league’s concussion management efforts.
“We had a clinic for our coaches with the doctors from the University of Miami, we have a policy where all coaches and parents have to sign off on concussion documents, and the AYFL has kept a database of all the concussed kids,” Sinel said.
In addition to the new state law which went into effect July 1, Broward County Schools have mandated baseline concussion testing for all high school athletes.
In Palm Beach County, more than 600 football players have participated in voluntary baseline testing.
All of that has helped lead to increased education and awareness of an often-misunderstood injury that if not treated properly, could have lasting effects on young brains.
“I think it’s all helping people do their jobs more effectively,” said Stephen Russo, the director of Sports Psychology at the Nova Southeastern University Sports Medicine Clinic. “The athletic trainers are overseeing the return-to-play protocol, the doctor is doing the medical approval, I’m doing what I’m trained to do and the coaches, at the end of the day, are doing what they’re trained to do. Everyone has their assigned roles in helping the athletes.”
Russo is working with the Broward County Athletic Association to carry out its baseline testing program. He estimates that this year, more than 50 athletes already have come to Nova’s Sports Medicine Clinic for post-concussion evaluation. In the entirety of the 2011-2012 school year, the clinic saw 101 cases.
At Cleveland Clinic in West Palm Beach where Dr. Evan Peck is helping Palm Beach County schools carry out its voluntary testing, there’s been an increase in patients, too.
A. Dettwiler, M. Murugavel, M. Putukian, R. Echemendia, V. Cubon, J. Furtado, D. Osherson
Princeton Neuroscience Institute, Princeton University
Department of Psychology, Princeton University, NJ
Avoiding recurrent injury in sports related concussion (SRC) requires understanding the neural mechanisms involved in recovery.Prior studies have reported functional differences of brain activation in athletes with SRC. fMRI studies using working memory tasks suggest altered patterns of activation in the dorsolateral prefrontal cortex. Chen et al. (2004) reported fewer task-related activations and significantly decreased BOLD signal changes in the DLPFC in athletes with persistent symptoms compared to normal controls. Differences in brain activation in response to varying degrees of working memory processing load (N-back: 0, 1, 2 and 3 back) were identified by McAllister et al. (1999) in subjects with mTBI (Glasgow score 13-15) within one month after injury. The primary purpose of this study was to define neural correlates of SRC during the 2 month following injury, using a working memory task and fMRI.
Repetitive hits on the head that are below the threshold for causing a concussion may still result in changes in the brain’s white matter, a small study of soccer players suggested.
On average, elite male soccer players — who often use their heads to direct the ball — had a range of negative changes in white matter architecture compared with a group of competitive swimmers who were unlikely to have repetitive brain trauma, according to Inga Koerte, MD, of Harvard Medical Schools Psychiatry Neuroimaging Laboratory in Boston, and colleagues.
Those differences were observed even though none of the participants in either group had a history of concussion, Koerte and colleagues reported in a research letter in the Nov. 14 issue of the Journal of the American Medical Association.
Although it is possible that frequent heading of the ball could explain the impairments in the soccer players, “differences in head injury rates, sudden accelerations, or even lifestyle could contribute,” the authors wrote.
Previous studies have shown that repetitive traumatic brain injury can have negative long-term consequences — including impaired white matter integrity — but the effects of frequent subconcussive head impacts are less clear.
Koerte and colleagues explored the issue using high-resolution diffusion tensor imaging, which can detect changes in white matter architecture.
The study included 12 right-handed male soccer players from an elite-level soccer club in Germany. All had trained since childhood for a professional career. Their mean age was 19.7 and they had been playing for an average of more than 13 years.
The control group consisted of 11 competitive swimmers who were matched by age, handedness, and sex. Their mean age was 21.4 and they had trained for an average of more than 9 years.
None of the participants in either group had a history of concussion or any neuropsychiatric disorders.
All underwent diffusion tensor imaging to measure markers of mild traumatic brain injury (fractional anisotropy and mean diffusivity) and axonal and myelin pathology (axial and radial diffusivity).
After adjustment for age and years of training, the soccer players showed increased radial diffusivity “in the right orbitofrontal white matter, the genu and anterior portions of the corpus callosum, association fibers involving bilateral inferior fronto-occipital fasciculus, bilateral optic radiation, and bilateral anterior cingulum, right anterior, right superior, and bilateral posterior corona radiata, right anterior limb of the internal capsule, right external capsule, and right superior frontal gyrus” (P<0.05 for all).
A widespread increase in radial diffusivity also has been seen in patients with mild traumatic brain injury and suggests possible demyelination, according to the researchers.
Soccer players also had higher axial diffusivity in the corpus callosum, but there were no differences between the groups in fractional anisotropy or mean diffusivity.
A neuroradiologist found no abnormalities in structural images of the brain.
The researchers could not exclude the possibility that heading the soccer ball resulted in the changes in white matter architecture, but they said that the reason remains unclear.
As an alternate explanation, they noted that “soccer players showed increased axial diffusivity in the absence of increased radial diffusivity limited to the corpus callosum, possibly resulting from specialized training or neuroinflammation.”
The authors acknowledged that the study was limited by the small sample size, the use of a single cross-sectional evaluation, and the lack of information on functional outcomes.
The study was supported by the Else Kröner-Fresenius Stiftung and the Deutsche Akademischer Austauschdienst. It was also supported in part by the Intrust Post-traumatic Stress Disorder and Traumatic Brain Injury Clinical Consortium, which is funded by a Department of Defense Psychological Health/Traumatic Brain Injury Research Program grant, and by a grant from the National Institute of Neurological Disorders and Stroke.
Koerte reported receiving a fellowship from the German Academic Exchange Service and Else Kröner- Fresenius Stiftung; having a grant pending with the NIH; and receiving travel expenses and accommodations from the Society for Neuropediatrics in Germany. Her co-authors reported relationships with Springer Publishing, Bracco, Philips Radiology, Munich Medical International, Deutsches Zentrum fuer Neurodegenerative Erkrankungen, Friedrich-Baur Stiftung, Arbeitsgemeinschaft Botulinumtoxin, Deutsche Forschungsgemeinschaft, Omnibus Stiftung, Guerbet, Merck-Serono, the Radiological Society of North America, Philips, Siemens, Deutsche Roentgengesellschaft, Alfried-Krupp-Stiftung, Bayer-Schering, Thieme Medical Publishers, the European Society of Radiology, Asklepios Clinics, Eurobioimaging, the German National Cohort, Munich Cluster of Excellence M4 Imaging, BMBG German Centers for Lung Diseases and Cardiovascular Diseases, the NIH, the Department of Defense, the International Brain Injury Association, Demos Books, Elsevier, Intrust, the U.S. Department of Veteran Affairs, the National Alliance for Medical Imaging, the National Institute of Mental Health, National Alliance for Research in Schizophrenia and Depression, Fogarty International Center, National Health and Medical Research Council, Silvio Conte Centers for Basic Translational Mental Health Research, and the 9th World Congress on Brain Injury.