Undiagnosed sports concussion? New research turns the issue on its head

The Browns’ Darius Randall, the Eagles’ Carson Wentz, the Giants’ Sterling Shepard — all were diagnosed with concussions in the first two weeks of the 2019 NFL season. Head injuries in the NFL are not new, but with the increased spotlight on their long-term effects to player health, the league has implemented protocol to address the diagnosis and management of concussions. That protocol includes immediate removal from the field with medical evaluation, and no game day return-to-play if a player is diagnosed with a concussion.

Concussions are mild Traumatic Brain Injuries (mTBIs) but they’re really anything but mild

The CDC estimates that between 1 and 3 million sports concussions happen each year to children and adults, in both professional and recreational sports. Concussion is defined as a type of traumatic brain injury caused by a blow to the head that causes the brain to move rapidly back and forth (like a collision with another player or a wall, a fall, or a hit by a ball or a puck). This sudden movement inside the head can create chemical changes in the brain, sometimes stretching and damaging brain cells. 

Medical professionals often describe concussions as a ‘mild’ traumatic brain injury because they are usually not life-threatening, but their effects on day-to-day life can be serious, and include:

• Cognitive issues – visual disruptions, problems with memory and attention 
• Emotional issues – depression, irritability, mood and personality changes
• Physical issues – headache, dizziness and balance issues, difficulty with sleep, seizures, excess fatigue 

But what happens when athletes get a head whack but show no symptoms of concussion?

Are they at the same risk for long term problems as those who are diagnosed with concussion? And is there a way to diagnose a concussion which has no overt symptoms? The answer to both is “yes”, based on recent published research.

Despite the increased focus on head injury in sports, concussions may still go undiagnosed, either due to lack of proper medical protocol on the field or lack of traditional  symptoms experienced by the player. The problem is that these smaller, milder hits to the head (‘subconcussive injuries’), although initially undetected, can still have a significant impact on thinking, memory, emotions and behavior, and can create lasting damage if there’s enough of them over time.

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Two new scientific studies investigated the impacts to the brain and potential earlier detection of undiagnosed concussion

In the first study, A common neural signature of brain injury in concussion and subconcussion  published in Science Advances, researchers wanted to document what happens inside the heads of football players who repeatedly collide with the ground and each other but who have not been diagnosed with a concussion. 

Researchers scanned the brains of players on the University of Rochester’s football team before, during and after the season, and outfitted them with special helmets that detected head hits which enabled researchers to note which players received head hits that resulted (or didn’t result in) concussion symptoms. After removing the diagnosed concussed players from the study, but keeping in players who had hit their heads with regularity (their helmets recorded a startling total of 19,128 impacts), researchers saw a  disconcerting difference in these players’ midbrains (the topmost portion of the brain stem) in post-season scans. “There was a kind of fraying of the tissue; the area’s white matter, which is the tissue that connects neurons, was slightly less healthy now,” says Dr. Adnan Hiran, one of the lead researchers. Bottom line? The scans and helmet data suggest that head impacts from sports can injure brain tissue, whether diagnosed as a concussion or not.

The second study offers hope for detecting concussion in asymptomatic head hits. Blood test detects concussion and subconcussive injuries in children and adults, published in BMJ Paediatrics Open, also addressed the issue of people who suffer head trauma without overt concussion symptoms. In this new study, researchers wanted to see if they could identify a subconcussive hit through a blood test that detects two proteins found in the brain – GFAP and UCH-L1. These proteins are considered biomarkers that appear in the blood after an injury, and if levels are high enough, are a sign of brain injury or concussion. 

Researchers hope the successful results of this study will move them closer toward developing an effective blood test to identify brain injuries, with the idea that earlier detection can help prevent further damage and reduce the risk of negative long-term effects.

Concussion awareness is key

Whether it’s Concussion Awareness Day or not, it’s critical that parents, friends, coaches, trainers, physicians, and athletes know the signs and symptoms of concussion and what to do if one is suspected​. Spreading the word that symptoms may not appear until days after a head hit, may even be missed, or may not appear at all, can help prevention, detection and care in the future.

For a deeper dive

• The Centers for Disease Control (CDC): Sports action plan
• Symptoms of concussion | Brain Injury Association of America
• NCAA Sports Medicine Handbook