American football continues to be the most popular sport in the US As compared to combat sports such as boxing, concussive injuries to the brain in football occur accidentally when there is a head impact exposure (HIE) due to the player’s helmeted head encountering the opposing player (s) helmeted head, torso, or turf. Sub-concussive injuries are often not brought to medical attention as the symptoms are mild and entirely subjective. While the true incidence of chronic traumatic encephalopathy (CTE) — a neurodegenerative disease linked to repeated head trauma in football players — remains a contentious issue among experts, it is a cause of grave concern for everyone involved in the sport. To protect players’ brain health, the National Football League (NFL) implemented best practices and guidelines for concussion evaluation and management.
Recently, the evaluation and management of Miami Dolphins quarterback Tua Tagovailoa’s HIE ignited calls for changes to the NFL concussion evaluation and management protocols to enhance player safety. A new protocol took effect this past weekend. More broadly, the uproar begs an important question: can we truly protect football players from acute and chronic neurological sequelae of multiple HIEs?
Concussion Definition and Evaluation
Concussion is defined as a clinical syndrome characterized by immediate and transient alteration in brain function, including alteration of mental status and level of consciousness, resulting from mechanical force or trauma. It is important to remember that loss of consciousness is not required for a concussion. Concussions are informally and non-scientifically graded as mild, moderate, and severe based on the duration of loss of consciousness (< or >30 minutes) and post traumatic amnestic period. Concussive properties of any HIE sustained in football depend upon the force, velocity, and angle of the hit to the helmeted cranium and how the mechanical forces are transferred and absorbed through the intracranial cavity. Both linear and rotational (angular) acceleration forces play a role as does impact deceleration occurring when the athlete falls and strikes his head against the ground.
The nature of contact sports such as football is such that HIEs cannot be completely avoided. To fully avoid HIEs would require significant rule changes and would alter the very nature of the game. This would be unacceptable to fans and other stakeholders. Abundant medical literature highlights the long-term health significance of multiple HIEs. Minor concussions (sub concussive injuries) contribute to the development of CTE, a neurodegenerative disorder presenting with a constellation of cognitive, mood, and behavioral changes along with motor system dysfunction (parkinsonism), usually after the athlete has retired. The symptoms of concussion are at times subjective such as headache, dizziness, nausea, light sensitivity, sound sensitivity, and cognitive dysfunction.
Frequently, when athletes sustain HIEs, they themselves are unaware that they are concussed and continue to play. In the absence of objective clinical signs, the concussion may be “missed” by medical staff on the sidelines. Hence when an athlete sustains a HIE, they must be closely observed and if concern for concussion arises, be pulled out of the game to undergo concussion evaluation. While this can be conducted on the sidelines, evaluation in the locker room where the athlete is less likely to be distracted is more ideal. Some athletes exhibit motor signs such as impaired coordination, balance, and stance after a concussion while others exhibit only cognitive dysfunction, emphasizing the importance of multimodal concussion assessment. This includes use of Maddocks questions (“Where are you?” “Who are you playing?” “Who did you play last week?” “What quarter is this?”) to gauge awareness, and standardized concussion assessment tools such as the Sport Concussion Assessment Tool-5 (SCAT5), King-Devick test, and Balance Error Scoring System (BESS).
The job of neurotrauma physicians and team physicians on the sidelines is not easy. There is currently no validated imaging or biofluid (blood or cerebrospinal fluid) biomarkers for concussion. In the absence of biomarkers, the diagnosis of concussion on the sidelines is made clinically based on the history of HIE followed by characteristic post-concussion symptoms (PCS).
Management of Concussive Injury
The athlete’s mentality is to never quit. Some athletes will deny symptoms of a concussive injury to the brain. Concussive symptoms may be fleeting, and an athlete may “clear” the multimodal concussion assessment in the locker room only to become symptomatic on his return to the field. Physicians on the sidelines should be aware of both of these possibilities. An athlete who has suffered a concussion should be pulled out of play and “benched.” This is done for two reasons. A concussed athlete with impaired attention, concentration, balance, and coordination is more prone to a second HIE if they return to play prematurely. The second reason is that if the concussed athlete continues to play, they will exhibit more profound and prolonged PCS. The benched athlete is advised of a period of cognitive and physical rest. The rationale for this is that a concussed brain is in a state of energy crises, and fares better with fewer cognitive and physical demands. Cognitive rest entails pulling back from cognitive activities such as team meetings and screen time. Physical rest entails pulling back from physical activities such as practice and drills. Complete cocooning is ill-advised with the latest research finding it may be detrimental and lead to prolongation of PCS.
While some athletes recover quickly (5-10 days), concussive symptoms persist longer in others and may reappear on returning to the field after successfully completing the post-concussion return to play protocol. In the absence of scientific data, there is no agreement among experts on the ideal duration of rest period following a concussion, leaving independent neurotrauma consultants and team physicians to face the conundrum of trying to determine when the athlete can be cleared to return to the game .
Making Contact Sports Safer
Concussion is a common head injury in football. Timely identification of the concussed athlete using multimodal concussion assessment tools, and immediate removal from play followed by a period of cognitive and physical rest until symptoms abate usually results in a good outcome.
Contact sports like football cannot be made completely safe, but they can be made safer. We continue to build on the cornerstones of enhanced medical supervision of the sport; standardized and enhanced concussion protocols including more comprehensive NO-GO criteria; and continued education of concerned parties on concussion recognition and management. No two concussions are the same. Advances in neuroimaging and development of sensitive and specific imaging and biofluid biomarkers for concussion and CTE will lead to the development of an evidence-based medicine approach to the management of concussions with the goal of personalized medicine and individual risk stratification of an athlete.
Tagovailoa’s recent concussion emphasizes that we need to do more to protect the brain health of these athletes. This means continuously reevaluating the concussion protocol and updating it as needed based on the latest research and knowledge. We owe it to them and their families.
Nitin K. Sethi, MD, MBBS, is an associate professor of neurology at NewYork-Presbyterian Hospital/Weill Cornell Medical Center.
Sethi serves as the chief medical officer of the New York State Athletic Commission. Sethi has, in the past, served as an NFL unaffiliated neurotrauma consultant and independent neurotrauma consultant. The views expressed by the author are his own and do not necessarily reflect the views of the institutions and organizations that the author serves.