Consent, capacity and compliance in concussion management: cave ergo medicus (let the doctor beware).

While the acute effects of concussion and mild traumatic brain injury (TBI) are well understood, the certainty in the medical literature regarding the long-term outcomes of sports-related concussion is limited. Long-term deficits that may result from single, repeated concussions, and possibly subconcussive impacts, include cognitive dysfunction, depression and executive dysfunction. Perhaps most troublingly, repetitive head impacts have been linked to neurodegenerative diseases, including chronic traumatic encephalopathy (CTE), although the precise risk of long-term consequences remains unknown. CTE represents a distinct tauopathy with an unknown incidence in athletic populations; however, a cause and effect relationship has not yet been demonstrated between CTE and concussions or between CTE and exposure to contact sports, as no prospective longitudinal studies have been performed to address that question. Studies of high-school sports exposure and long-term outcomes have not demonstrated consistent findings.Medical advice regarding return to play and the risk of acute and/or long-term consequences is therefore problematic. It is important that the individual's right to make their own choices regarding their health is respected. Team, coach, parental, peer or financial pressures should not influence this decision. The choice to return to play after a concussion or mild TBI injury is the athlete's decision once they have (1) recovered from their injury and have the legal capacity to make an informed decision; (2) been medically assessed and (3) been informed of any possible long-term risks in a language that they can understand.Given the current lack of certainty in relation to long-term outcomes from concussion, is it possible to provide a framework to inform players of current evidence, as part of a consent process, even if the information upon which the decision to return to sport is based remains uncertain and evolving?