Mild Traumatic Brain Injury (mTBI) also known as a concussion, is a growing public health concern. Accounting for 80-90% of all traumatic brain injuries, nearly 3 million Americans and 42 million people world-wide sustain a mTBI each year.1 This is likely under-reported as many who sustain mTBI do not present for medical attention and are thus undetected or under-treated. Although the majority with a mild TBI will recover within a few weeks, an estimated 15-20% will have persistent physical, psychological, and cognitive long term symptoms leading to long-term burden and disability.2 Of those with mTBI and normal head imaging seen in the Emergency department, 35% were reported to have functional limitations 12 months post-injury.2 In the USA, healthcare costs linked to non-fatal TBIs in 2016 were over USD 40.6 billion across Medicaid, Medicare, and private health insurance .3 Given the increasing morbidity associated with mTBI, research has focused on investigating acute management practices to improve symptom recovery and identify clinical signs that may predict poorer rehabilitation outcomes.

A concussion or mild TBI (mTBI) is defined as a trauma-induced physiological disruption of brain function resulting from a plausible mechanism of injury, presenting with a Glasgow Coma Scale (GCS) score of 13-15 and normal structural head imaging.4 This article will explore adult concussions in the general population with special emphasis in the athletic and military context, as they comprise a significant proportion of mTBI sustained in the United States.

The most recent consensus statement from Concussion in Sport Group (CISG) noted the initial step to managing an acute concussion is recognizing one occurred. 4 If a concussion is suspected, then immediate removal of the athlete or service member is required to receive treatment and avoid further risk of injury.5,6 Physical exam should include a multimodal evaluation of symptoms, signs, balance, gait, neurological, and cognitive changes associated with a potential concussion. Red flag symptoms that may prompt emergency transport for further evaluation include sustained loss of consciousness, convulsions or tonic posturing, falls without protective mechanisms, repetitive vomiting, amnesia, as well as rapid deterioration of symptoms. 5

Regardless of mechanism, anyone suspected to have a concussion should not return to a game or active duty that day. Serial evaluations are recommended as the presentation of concussion may evolve over time, ranging from several hours to days.5 It is recommended to allot at least 10-15 minutes to conduct a multimodal screen for potential concussion.4 In terms of sideline screening tools for athletes, The Maddocks questions remains a useful and brief on-field screen for athletes > 12 years of age without clear on-field signs of concussion.5 The Standardized Assessment of Concussion (SAC) and Balance Error Scoring System (BESS) also exhibit diagnostic utility for acute sports related concussions, assessing cognitive and postural stability respectively.7 CISG suggests the Sports Concussion Assessment Test (SCAT) has optimum utility in the 72 hours and up to a week after injury.4 For service members (SMs), Military Acute Concussion Evaluation (MACE2) and Neurobehavioral Symptom Inventory (NSI) evaluation should be administered as close to the time of injury onset when tactically safe to do so. 8,9

Once immediate risk is eliminated, physical and cognitive relative rest are recommended for the first 24-48 hours following concussion. 5,6 Recent studies have reaffirmed the strategy of allowing relative rest instead of formerly prescribed restrictive rest, also known as cocooning, which has demonstrated higher symptom burden and greater risk of experiencing post-concussive syndrome.6,10 Relative rest is defined as “physical and cognitive activities that do not provoke symptoms.” 10 Participants are allowed to progress in return to activity protocol if the exercise or cognitive intensity does not exacerbate symptoms significantly, further characterized as more than 2 points on a 1-10 scale in severity and less than 1 hour. 5

Physical exam should pertinently focus on mental status, vestibular-ocular systems, cervical range of movement, cervical muscle tenderness, balance, and gait testing.11 Orthostatic vitals may also be considered to evaluate for autonomic dysfunction.12 Clinicians should ascertain history of premorbid conditions to stratify risks of prolonged symptoms; pertinent history includes prior concussions, migraines, psychiatric conditions, seizures, learning disabilities, and substance abuse. It is imperative when diagnosing concussion, to provide reassurance and education of the recovery process. This form of psychoeducation has been found to reduce risk of persistent symptoms. 12,13