Current Concepts in Sports-Related Concussion.

Traumatic brain injury, specifically concussion, is prevalent in contact sports. In the United States (US) each year, 170 million adults participate in physical recreational activities, and 38 million children and adolescents participate in organized sports. The Centers for Disease Control estimate that in this group ~1.6 to 3.8 million concussions occur annually. Recent class-action lawsuits in the US filed by professional athletes against their respective leagues allege negligence in protecting them from concussions, and this has contributed to the attention received in the popular media. In response, concussion-related publications have increased exponentially during the past several years. Recent studies have challenged earlier assumptions that the effects of concussion are transient. Stronger links between concussion and neurodegenerative processes such as Alzheimer's disease-like conditions, depression, and heightened risk for suicide are being elucidated. In this article, we explore the current knowledge on concussion, including pathophysiology, management, and long-term effects. We conclude that more evidence-based results regarding guidelines for diagnosis, treatment, and return to play (RTP) are needed and should be the focus of future investigations. Attributing the etiology of certain neurodegenerative conditions to a history of concussion has been suggested in the current literature, but additional quantitative data regarding the pathophysiology and causality are needed as well. Bioengineers can have an important role in measuring the dynamic forces encountered during head impacts and their effects on the brain. These results can be effective in designing better helmets as well as improved playing surfaces to reduce the impact of such injuries. At this time, we believe that groups of people with heightened risk for concussion should be followed closely during longer periods of time and compared to matched controls. Such long-term studies are urgently needed to develop appropriate guidelines for safety and protect our young and adult athletes in the future.