Traumatic Encephalopathy Related to Sports Injury

US Neurology, 2011;7(1):33-6 DOI: http://doi.org/10.17925/USN.2011.07.01.33

There has been tremendous research and development in designing new helmets, but their effectiveness in preventing concussions has not been proven. Mouth guards can reduce dental injuries but also have little impact on preventing concussions. There is some concern that protective equipment results in more aggressive play and may paradoxically increase the incidence of injuries.27

Much of the focus on preventing CTE centers on avoiding repeat brain injuries that occur within a short time frame. Return to play (RTP) guidelines have been developed that will hopefully decrease the risk of catastrophic injuries such as second impact syndrome as well as CTE. The RTP guidelines are based on concussion severity and require that the athlete be symptom free for at least one week before being considered ready to return (see Table 3). When a second concussion is suffered, the time period that the athlete must wait varies from two to four weeks depending on concussion severity. After three concussions (two if severe), the player should terminate the season and return the next year. For purposes of the RTP guidelines, an asymptomatic patient is one that is free of symptoms both at rest and exertion.

Conclusions
CTE is a growing public health concern and recent evidence suggests that younger athletes (particularly girls) are at greater risk of concussion due to less developed neck muscles, which allow a greater force to be exerted on the brain from trauma. The pathologic changes are similar to AD, but there are key differences in tau protein and amyloid deposition. As our sophistication around concussion detection and prevention improves, hopefully the incidence of CTE will decline.

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Keywords: Concussion, mild traumatic brain injury, chronic traumatic encephalopathy, tauopathy, Alzheimer’s disease, dementia, sports injury, dementia pugilistica