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Management of Concussion and Mild Traumatic Brain Injury: A Synthesis of Practice Guidelines

Open AccessPublished:October 22, 2019DOI:https://doi.org/10.1016/j.apmr.2019.10.179

      Abstract

      At least 3 million Americans sustain a mild traumatic brain injury (mTBI) each year, and 1 in 5 have symptoms that persist beyond 1 month. Standards of mTBI care have evolved rapidly, with numerous expert consensus statements and clinical practice guidelines published in the last 5 years. This Special Communication synthesizes recent expert consensus statements and evidenced-based clinical practice guidelines for civilians, athletes, military, and pediatric populations for clinicians practicing outside of specialty mTBI clinics, including primary care providers. The article offers guidance on key clinical decisions in mTBI care and highlights priority interventions that can be initiated in primary care to prevent chronicity.

      Keywords

      List of abbreviations:

      AMS (altered mental status), CT (computed tomography), mTBI (mild traumatic brain injury), SCAT5 (Sport Concussion Assessment Tool–5th Edition), TBI (traumatic brain injury)
      Traumatic brain injury (TBI) occurs when an external force to the head or body alters brain function.
      • Menon D.K.
      • Schwab K.
      • Wright D.W.
      • Maas A.I.
      Position statement: definition of traumatic brain injury.
      Almost half of Americans have sustained at least 1 TBI in their lifetime.
      • Whiteneck G.G.
      • Cuthbert J.P.
      • Corrigan J.D.
      • Bogner J.A.
      Risk of negative outcomes after traumatic brain injury: a statewide population-based survey.
      There are 3-4 million new cases of TBI each year in the United States
      • Coronado V.G.
      • McGuire L.C.
      • Sarmiento K.
      • et al.
      Trends in traumatic brain injury in the U.S. and the public health response: 1995-2009.
      and 30-50 million worldwide.
      • Maas A.I.
      • Menon D.K.
      • Adelson P.D.
      • et al.
      Traumatic brain injury: integrated approaches to improve prevention, clinical care, and research.
      The TBI incidence rate has been increasing.
      • Coronado V.G.
      • McGuire L.C.
      • Sarmiento K.
      • et al.
      Trends in traumatic brain injury in the U.S. and the public health response: 1995-2009.
      ,
      • Dams-O’Connor K.
      • Cuthbert J.P.
      • Whyte J.
      • Corrigan J.D.
      • Faul M.
      • Harrison-Felix C.
      Traumatic brain injury among older adults at level I and II trauma centers.
      • Marin J.R.
      • Weaver M.D.
      • Yealy D.M.
      • Mannix R.C.
      Trends in visits for traumatic brain injury to emergency departments in the United States.
      • Hsia R.Y.
      • Markowitz A.J.
      • Lin F.
      • Guo J.
      • Madhok D.Y.
      • Manley G.T.
      Ten-year trends in traumatic brain injury: a retrospective cohort study of California emergency department and hospital revisits and readmissions.
      Falls are the most common cause, especially in young children and older adults.
      Centers for Disease Control and Prevention. Surveillance Report of Traumatic Brain Injury-related Emergency Department Visits, Hospitalizations, and Deaths—United States, 2014.
      The vast majority of TBIs (up to 90%)
      • Kay A.
      • Teasdale G.
      Head injury in the United Kingdom.
      are classified as “mild” (mTBI), meaning that they involve no or only a brief (<30min) loss of consciousness and period of posttraumatic amnesia (<24h).
      Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation
      Definition of mild traumatic brain injury.
      Management of mTBI largely occurs outside of the hospital. Although the emergency department is the typical point of entry into the health care system, increasingly, patients with mTBI are first seeking medical attention from a community-based primary care provider.
      • Arbogast K.B.
      • Curry A.E.
      • Pfeiffer M.R.
      • et al.
      Point of health care entry for youth with concussion within a large pediatric care network.
      • Taylor A.M.
      • Nigrovic L.E.
      • Saillant M.L.
      • et al.
      Trends in ambulatory care for children with concussion and minor head injury from eastern Massachusetts between 2007 and 2013.
      • Theadom A.
      • Starkey N.
      • Barker-collo S.
      • Jones K.
      • Ameratunga S.
      • Feigin V.
      Population-based cohort study of the impacts of mild traumatic brain injury in adults four years post-injury.
      • Rao D.P.
      • Mcfaull S.
      • Thompson W.
      • Jayaraman G.C.
      Traumatic brain injury management in Canada: changing patterns of care.
      Primary care providers and specialists (eg, neurologists, physiatrists, etc) unattached to a TBI-specific clinic are often relied on to provide and/or arrange early follow-up care.
      • Seabury S.A.
      • Gaudette É.
      • Goldman D.P.
      • et al.
      Assessment of follow-up care after emergency department presentation for mild traumatic brain injury and concussion: results from the TRACK-TBI Study.
      Traditionally, mTBI has been thought to require minimal clinical management beyond watchful waiting.
      • Mann A.
      • Tator C.H.
      • Carson J.D.
      Concussion diagnosis and management: knowledge and attitudes of family medicine residents.
      In response to mounting evidence that mTBI can be associated with chronic symptoms and disability,
      • Dikmen S.
      • Machamer J.
      • Fann J.R.
      • Temkin N.R.
      Rates of symptom reporting following traumatic brain injury.
      • McMahon P.
      • Hricik A.
      • Yue J.K.
      • et al.
      Symptomatology and functional outcome in mild traumatic brain injury: results from the prospective TRACK-TBI study.
      • Theadom A.
      • Barker-Collo S.
      • Jones K.
      • et al.
      Work limitations 4 years after mild traumatic brain injury: a cohort study.
      • de Koning M.E.
      • Scheenen M.E.
      • van der Horn H.J.
      • et al.
      Non-hospitalized patients with mild traumatic brain injury: the forgotten minority.
      standards for mTBI care have evolved to promote earlier and more proactive intervention.
      • Collins M.W.
      • Kontos A.P.
      • Okonkwo D.O.
      • et al.
      Statements of agreement from the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      Numerous expert agreement statements and clinical practice guidelines have been published within the last 5 years.
      • Collins M.W.
      • Kontos A.P.
      • Okonkwo D.O.
      • et al.
      Statements of agreement from the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      • Broglio S.P.
      • Cantu R.C.
      • Gioia G.A.
      • et al.
      National Athletic Trainers’ Association position statement: management of sport concussion.
      • Giza C.C.
      • Kutcher J.S.
      • Ashwal S.
      • et al.
      Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology.
      • McCulloch K.L.
      • Goldman L.S.
      • Lowe L.
      • et al.
      Development of clinical recommendations for progressive return to activity after military mild traumatic brain injury: guidance for rehabilitation providers.
      • Collins M.W.
      • Kontos A.P.
      • Okonkwo D.O.
      • et al.
      Statements of agreement from the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.
      • Unden J.
      • Ingebrigtsen T.
      • Romner B.
      Scandinavian guidelines for the acute management of adult patients with minimal, mild, or moderate head injuries: an evidence and consensus-based update.
      The present review aims to synthesize this rapidly advancing knowledge for the clinician whose primary practice is not mTBI. We provide evidence-based recommendations to guide key clinical decisions and highlight priority interventions that can be initiated by nonexpert clinicians to potentially prevent chronicity.
      The recommendations in this article will generally apply across age (school-aged children through adulthood) and injury setting (trauma, sport, military), although tailoring care to each is advisable. Note that some consensus statement and guideline documents synthesized here were intended to apply only to patients with “uncomplicated” mTBI (also known as “concussion” and characterized by an absence of trauma-related intracranial abnormalities on conventional structural neuroimaging),
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      whereas others were intended to apply to the full spectrum of mTBI.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      The recommendations outlined below can be used for patients with uncomplicated and complicated mTBI, at the clinician’s discretion.

      Methods

      An interdisciplinary group of content experts (American Congress of Rehabilitation Medicine Brain Injury Interdisciplinary Special Interest Group Mild TBI Task Force) extracted evidence-based recommendations from the latest versions of expert consensus statements and clinical practice guidelines for school-aged children,
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      • Astrand R.
      • Rosenlund C.
      • Undén J.
      • et al.
      Scandinavian guidelines for initial management of minor and moderate head trauma in children.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      • Astrand R.
      • Rosenlund C.
      • Undén J.
      • et al.
      Scandinavian guidelines for initial management of minor and moderate head trauma in children.
      adult civilians,

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Unden J.
      • Ingebrigtsen T.
      • Romner B.
      Scandinavian guidelines for the acute management of adult patients with minimal, mild, or moderate head injuries: an evidence and consensus-based update.
      athletes,
      • Collins M.W.
      • Kontos A.P.
      • Okonkwo D.O.
      • et al.
      Statements of agreement from the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.
      ,
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • Broglio S.P.
      • Cantu R.C.
      • Gioia G.A.
      • et al.
      National Athletic Trainers’ Association position statement: management of sport concussion.
      ,
      • Giza C.C.
      • Kutcher J.S.
      • Ashwal S.
      • et al.
      Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology.
      and military populations
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      • McCulloch K.L.
      • Goldman L.S.
      • Lowe L.
      • et al.
      Development of clinical recommendations for progressive return to activity after military mild traumatic brain injury: guidance for rehabilitation providers.
      with mTBI. To incorporate the most up-to-date evidence, a supplementary MEDLINE search was performed on December 14, 2018, to identify recent systematic reviews by combining mTBI-related terms with a validated search filter for systematic reviews
      • Montori V.M.
      • Wilczynski N.L.
      • Morgan D.
      • Haynes R.B.
      Optimal search strategies for retrieving systematic reviews from Medline: analytical survey.
      (supplemental appendix S1, available online only at http://www.archives-pmr.org/).
      A narrative synthesis of the consensus statements, clinical practice guidelines, and updated evidence follows. To supplement the narrative, we identified management recommendations that were consistent across the most recent and widely cited statement or guideline for each of the following areas: adults,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      children,
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      military,
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      and sports.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      To be included, a management recommendation had to (1) be explicit in at least 3 of the 4 core statements or guidelines and (2) be implied by, or at least consistent with any core statement or guideline that did not recommend the strategy explicitly. Eligible management recommendations, their associated strength (using guideline-specific grading systems), and their location within the source document were extracted by 2 authors independently (N.S. and K.M.), with discrepancies resolved by a third (W.P.), and are presented in table 1.
      Table 1Recommendation number/location and strength
      VariableONFCDCVA/DoDCISG
      Prompt diagnostic evaluation1.1 (A)C2 (Strong)Pg. 3-4
      No routine neuroimaging1.3 (A)1A/1B, 2 (B)3 (Weak)C
      No clinical use of serum biomarkersC6 (R)3 (Weak)Pg. 5
      Advice to rest for 1-3 d post injury3.4 (A)
      Recommendation is repeated in 4.5 and 12.5.
      13A (B)C
      Detailed recommendations for clinicians regarding rest and return to activity in an active duty military setting are covered in the Defense and Veterans Brain Injury Center’s (2014) Progressive Return to Activity Following Acute Concussion/Mild TBI (accessed May 2, 2019: https://dvbic.dcoe.mil/material/progressive-return-activity-following-acute-concussionmild-tbi-clinical-suite).
      Pg. 5
      Guidance on gradual stepwise return to preinjury activities3.4 (A),

      12.3 (A)
      13B, 13D (B)C
      Detailed recommendations for clinicians regarding rest and return to activity in an active duty military setting are covered in the Defense and Veterans Brain Injury Center’s (2014) Progressive Return to Activity Following Acute Concussion/Mild TBI (accessed May 2, 2019: https://dvbic.dcoe.mil/material/progressive-return-activity-following-acute-concussionmild-tbi-clinical-suite).
      Pg. 5, 7
      Early education for patient/family2.3 (A),

      2.6 (A)
      7A/7B (B), 12 (A)11, 15, 22 (Weak)C
      Use validated symptom scales for initial assessment and to track recovery4.1 (C)5A, 10B (B)CPg. 3, 4, 7
      Neuropsychological assessment to investigate persistent (>30d) cognitive symptoms9.4 (A)19C (C)17 (Weak)C
      Referral to specialist or higher level of care for slow to recover patients (>10-14d for adult athletes, >30d for others)2.4 (C)11B/15F (B)21 (Weak)Pg. 5
      NOTE. C, consistent with but not explicitly recommended in guideline/statement.
      CDC, Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children (2019). Strength of recommendations: A, almost always should be followed; B, usually should be followed; C, may sometimes be followed; R, intervention generally should not be done outside of a research setting; U, insufficient evidence.
      CISG, Consensus Statement on Concussion in Sport–the 5th International Conference on Concussion in Sport (2016). Strength of recommendations: Not applicable.
      ONF, Ontario Neurotrauma Foundation Guideline for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms (3rd edition; 2018). Levels of evidence: A, ≥1 randomized controlled trial, meta-analysis, or systematic review; B, ≥1 cohort comparison, case study, or other type of experimental study; C, expert opinion, experience, or consensus panel.
      VA/DoD, Department of Veterans Affairs/Department of Defense Clinical Practice Guideline for the Management of Concussion-Mild Traumatic Brain Injury (2016). Strength of recommendations: Strong For, Weak For, Strong Against, Weak Against.
      Recommendation is repeated in 4.5 and 12.5.
      Detailed recommendations for clinicians regarding rest and return to activity in an active duty military setting are covered in the Defense and Veterans Brain Injury Center’s (2014) Progressive Return to Activity Following Acute Concussion/Mild TBI (accessed May 2, 2019: https://dvbic.dcoe.mil/material/progressive-return-activity-following-acute-concussionmild-tbi-clinical-suite).

      Discussion

      Pathophysiology

      Rapid acceleration/deceleration of the brain by mechanical force can disrupt cell membrane and axonal integrity, inducing a molecular cascade.
      • Giza C.C.
      • Hovda D.A.
      The new neurometabolic cascade of concussion.
      Normalization of altered brain metabolism, cerebrovascular function, and network connectivity following mTBI may lag behind clinical recovery.
      • Kamins J.
      • Bigler E.
      • Covassin T.
      • et al.
      What is the physiological time to recovery after concussion? A systematic review.
      Some patients with mTBI (12%-20%) will have macrostructural intracranial injury visible on computed tomography (CT); most common are cerebral contusions (disproportionately frontal-temporal), subdural hematomas, and subarachnoid hemorrhages.
      • Iverson G.L.
      • Lovell M.R.
      • Smith S.
      • et al.
      Prevalence of abnormal CT-scans following mild head injury.
      • Isokuortti H.
      • Iverson G.L.
      • Silverberg N.D.
      • et al.
      Characterizing the type and location of intracranial abnormalities in mild traumatic brain injury.
      • Stiell I.G.
      • Wells G.A.
      • Vandemheen K.
      • et al.
      The Canadian CT Head Rule for patients with minor head injury.
      Magnetic resonance imaging studies using modern techniques such as diffusion tensor imaging suggest that microstructural pathology (eg, weakened integrity of long white matter tracts) can also be a feature of mTBI,
      • Shenton M.E.
      • Hamoda H.M.
      • Schneiderman J.S.
      • et al.
      A review of magnetic resonance imaging and diffusion tensor imaging findings in mild traumatic brain injury.
      although the nature, location, time course, and clinical significance of such changes are unclear.
      • Asken B.M.
      • DeKosky S.T.
      • Clugston J.R.
      • Jaffee M.S.
      • Bauer R.M.
      Diffusion tensor imaging (DTI) findings in adult civilian, military, and sport-related mild traumatic brain injury (mTBI): a systematic critical review.
      • Schmidt J.
      • Hayward K.S.
      • Brown K.E.
      • et al.
      Imaging in pediatric concussion: a systematic review.
      • Khong E.
      • Odenwald N.
      • Hashim E.
      • Cusimano M.D.
      Diffusion tensor imaging findings in post-concussion syndrome patients after mild traumatic brain injury: a systematic review.

      Clinical presentation and diagnosis

      mTBI can be challenging to diagnose in any setting because the acute signs and symptoms of altered mental status (AMS) are often subtle and transient, and available diagnostic tests (eg, CT) are not sensitive. These issues may be compounded in primary care, where patients are often first evaluated days or even weeks after an injury event and factors that mimic mTBI-like symptoms (fig 1) may have emerged. Many novel biomarkers for mTBI are under development, but none have yet been validated for diagnostic purposes.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      ,
      • Zetterberg H.
      • Morris H.R.
      • Hardy J.
      • Blennow K.
      Update on fluid biomarkers for concussion.
      • McCrea M.
      • Meier T.
      • Huber D.
      • et al.
      Role of advanced neuroimaging, fluid biomarkers and genetic testing in the assessment of sport-related concussion: a systematic review.
      • Mayer A.R.
      • Kaushal M.
      • Dodd A.B.
      • et al.
      Advanced biomarkers of pediatric mild traumatic brain injury: progress and perils.
      • OʼConnell B.
      • Kelly Á.M.
      • Mockler D.
      • et al.
      Use of blood biomarkers in the assessment of sports-related concussion-a systematic review in the context of their biological significance.
      A clinical interview based on patient self-report (and corroborated with medical records, when available) with physical examination remains the criterion standard for diagnosing mTBI in primary care.
      Figure thumbnail gr1
      Fig 1Conditions that can mimic or exacerbate “postconcussion” symptoms.
      • Morin M.
      • Langevin P.
      • Fait P.
      • Morin M.
      • Langevin P.
      • Fait P.
      Cervical spine involvement in mild traumatic brain injury: a review.
      • Cheever K.
      • Kawata K.
      • Tierney R.
      • Galgon A.
      Cervical injury assessments for concussion evaluation: a review.
      • Kennedy E.
      • Quinn D.
      • Tumilty S.
      • Chapple C.
      Clinical characteristics and outcomes of treatment of the cervical spine in patients with persistent post-concussion symptoms: a retrospective analysis.
      • Leddy J.J.
      • Baker J.G.
      • Merchant A.
      • et al.
      Brain or strain? Symptoms alone do not distinguish physiologic concussion from cervical/vestibular injury.
      • Ernst A.
      • Basta D.
      • Seidl R.O.
      • Todt I.
      • Scherer H.
      • Clarke A.
      Management of posttraumatic vertigo.
      • Smith-Seemiller L.
      • Fow N.R.
      • Kant R.
      • Franzen M.D.
      Presence of post-concussion syndrome symptoms in patients with chronic pain vs mild traumatic brain injury.
      • Stålnacke B.M.
      Postconcussion symptoms in patients with injury-related chronic pain.
      • Silverberg N.D.
      • Iverson G.L.
      Is rest after concussion “the best medicine?”: recommendations for activity resumption following concussion in athletes, civilians, and military service members.
      • Meares S.
      • Shores E.A.
      • Batchelor J.
      • et al.
      The relationship of psychological and cognitive factors and opioids in the development of the postconcussion syndrome in general trauma patients with mild traumatic brain injury.
      • Kemp S.
      • Agostinis A.
      • House A.
      • Coughlan A.K.
      Analgesia and other causes of amnesia that mimic post-traumatic amnesia (PTA): a cohort study.
      • Harvey A.G.
      • Bryant R.A.
      Acute stress disorder after mild traumatic brain injury.
      • Laborey M.
      • Masson F.
      • Ribéreau-Gayon R.
      • Zongo D.
      • Salmi L.R.
      • Lagarde E.
      Specificity of postconcussion symptoms at 3 months after mild traumatic brain injury: results from a comparative cohort study.
      • Iverson G.L.
      Misdiagnosis of the persistent postconcussion syndrome in patients with depression.
      • Lange R.T.
      • Iverson G.L.
      • Rose A.
      Depression strongly influences postconcussion symptom reporting following mild traumatic brain injury.
      • Iverson G.L.
      • Silverberg N.D.
      • Mannix R.
      • et al.
      Factors associated with concussion-like symptom reporting in high school athletes.
      Given a lack of universally accepted diagnostic criteria for mTBI, a diagnostic process that integrates the most widely used criteria
      • Menon D.K.
      • Schwab K.
      • Wright D.W.
      • Maas A.I.
      Position statement: definition of traumatic brain injury.
      ,
      Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation
      Definition of mild traumatic brain injury.
      ,
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      is reasonable. The critical first step should be to establish a plausible injury mechanism. The mechanism of injury must transmit sufficient biomechanical energy to disrupt brain function, recognizing there are between-person variability thresholds.
      • Rowson S.
      • Duma S.
      • Stemper B.
      • et al.
      Correlation of concussion symptom profile with head impact biomechanics: a case for individual-specific injury tolerance.
      Blunt force trauma to the head is not required for mTBI diagnosis; in some cases, acceleration-deceleration (whiplash)
      Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation
      Definition of mild traumatic brain injury.
      ,
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      or explosion/blast forces
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      may cause an mTBI in the absence of contact between the head and another surface.
      Second, the clinician should query for signs and symptoms of AMS that presented immediately following the impact. The most compelling evidence of AMS is loss of consciousness (observed period of unresponsiveness), posttraumatic amnesia (gap in memory following the impact), or confusion (eg, inability to follow commands or disorientation to time or place). By some definitions, subtler symptoms such as slowed thinking
      • Menon D.K.
      • Schwab K.
      • Wright D.W.
      • Maas A.I.
      Position statement: definition of traumatic brain injury.
      or feeling dazed
      Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation
      Definition of mild traumatic brain injury.
      qualify as evidence of AMS. The onset of AMS typically abuts the moment of impact but may evolve over minutes.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • McCrory P.
      • Feddermann-Demont N.
      • Dvoøák J.
      • et al.
      What is the definition of sports-related concussion: a systematic review.
      Third, it is important that clinicians consider potential confounding factors and determine whether these factors may explain the AMS.
      • Menon D.K.
      • Schwab K.
      • Wright D.W.
      • Maas A.I.
      Position statement: definition of traumatic brain injury.
      ,
      • Holm L.
      • Cassidy J.D.
      • Carroll L.J.
      • Borg J.
      Summary of the WHO Collaborating Centre for Neurotrauma Task Force on Mild Traumatic Brain Injury.
      ,
      • Ruff R.M.
      • Iverson G.L.
      • Barth J.T.
      • Bush S.S.
      • Broshek D.K.
      Recommendations for diagnosing a mild traumatic brain injury: a National Academy of Neuropsychology education paper.
      The most common factor is probably alcohol or substance intoxication.
      • Scheenen M.E.
      • de Koning M.E.
      • van der Horn H.J.
      • et al.
      Acute alcohol intoxication in patients with mild traumatic brain injury: characteristics, recovery and outcome.
      ,
      • Lange R.T.
      • Iverson G.L.
      • Franzen M.D.
      Short-term neuropsychological outcome following uncomplicated mild TBI: effects of day-of-injury intoxication and pre-injury alcohol abuse.
      Other potential confounds include acute psychological stress, severe musculoskeletal pain, pulmonary or circulatory disruption, and syncope or hypoglycemia prior to a fall. People who are exposed to a psychologically traumatic event that does not involve mTBI (eg, witnessing violence) and react with panic (eg, fear of death, tachycardia, hyperventilation) can have difficulty recalling part or all of the event.
      • Harvey A.G.
      • Bryant R.A.
      Acute stress disorder after mild traumatic brain injury.
      Example questions for the diagnostic interview are provided in fig 2. The final step in the diagnostic process is to incorporate all available information into a probabilistic determination.
      • Deeks J.J.
      • Altman D.G.
      Diagnostic tests 4: likelihood ratios.
      Equivocal evidence of AMS may warrant an mTBI diagnosis if it occurred in the context of a high-energy impact and the absence of confounding factors. The decision to rule in mTBI must be weighed against the potentially iatrogenic consequences of a false positive mTBI diagnosis, such as misdirecting treatment so that a clinically important underlying condition (eg, posttraumatic stress) is not addressed.
      Figure thumbnail gr2
      Fig 2Diagnostic Interview for Mild Traumatic Brain Injury. Abbreviation: ADHD, attention-deficit/hyperactivity disorder.
      Postconcussion symptoms such as headache, dizziness, fatigue, irritability, and forgetfulness can support a diagnosis or trigger a diagnostic evaluation (and precautionary measures such as removal from sport)
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      but should generally not be used as the sole basis for diagnosing mTBI.
      • Ruff R.M.
      • Iverson G.L.
      • Barth J.T.
      • Bush S.S.
      • Broshek D.K.
      Recommendations for diagnosing a mild traumatic brain injury: a National Academy of Neuropsychology education paper.
      ,

      Centers for Disease Control and Prevention Report to Congress on Mild Traumatic Brain Injury in the United States: steps to prevent a serious public health problem; 2003. Available at: https://www.cdc.gov/traumaticbraininjury/pdf/mtbireport-a.pdf. Accessed June 11, 2018.

      mTBI-like symptoms are commonly reported by patients with traumatic injuries not involving the head or brain,
      • Meares S.
      • Shores E.A.
      • Batchelor J.
      • et al.
      The relationship of psychological and cognitive factors and opioids in the development of the postconcussion syndrome in general trauma patients with mild traumatic brain injury.
      ,
      • Meares S.
      • Shores E.A.
      • Taylor A.J.
      • et al.
      Mild traumatic brain injury does not predict acute postconcussion syndrome.
      ,
      • Cassidy J.D.
      • Cancelliere C.
      • Carroll L.J.
      • et al.
      Systematic review of self-reported prognosis in adults after mild traumatic brain injury: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.
      patients with a variety of health conditions that often co-occur with mTBI (see fig 1), and even by healthy people
      • Iverson G.L.
      • Lange R.T.
      Examination of “postconcussion-like” symptoms in a healthy sample.
      ,
      • Hunt A.W.
      • Paniccia M.
      • Reed N.
      • Keightley M.
      Concussion-like symptoms in child and youth athletes at baseline: what is “typical”?.
      ; the poor specificity of these symptoms weakens their diagnostic utility. Nevertheless, if a patient experiences new or worsened physical, cognitive, or emotional symptoms after a plausible mechanism of mTBI in the absence of AMS and confounding factors that might account for those symptoms (see fig 1), it would be prudent to proceed with clinical management under the assumption that the individual may have sustained an mTBI,
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      for example, by temporarily restricting the patient from safety-sensitive activities until their symptoms resolve and/or an alternative etiology is identified and addressed.

      Prognosis

      Recent inception cohort studies suggest that at least 1 in 5 patients with mTBI will experience symptoms that persist for longer than 1 month
      • Dikmen S.
      • Machamer J.
      • Fann J.R.
      • Temkin N.R.
      Rates of symptom reporting following traumatic brain injury.
      ,
      • McMahon P.
      • Hricik A.
      • Yue J.K.
      • et al.
      Symptomatology and functional outcome in mild traumatic brain injury: results from the prospective TRACK-TBI study.
      ,
      • de Koning M.E.
      • Scheenen M.E.
      • van der Horn H.J.
      • et al.
      Non-hospitalized patients with mild traumatic brain injury: the forgotten minority.
      ,
      • Theadom A.
      • Parag V.
      • Dowell T.
      • et al.
      Persistent problems 1 year after mild traumatic brain injury: a longitudinal population study in New Zealand.
      ,
      • Zemek R.
      • Barrowman N.
      • Freedman S.B.
      • et al.
      Clinical risk score for persistent postconcussion symptoms among children with acute concussion in the ED.
      and that recovery is frequently complicated by preexisting and comorbid health conditions.
      • Zetterberg H.
      • Morris H.R.
      • Hardy J.
      • Blennow K.
      Update on fluid biomarkers for concussion.
      ,
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • King N.S.
      • Kirwilliam S.
      Permanent post-concussion symptoms after mild head injury.
      Children return to school after a median of 2-4 days
      • Rozbacher A.
      • Selci E.
      • Leiter J.
      • Ellis M.
      • Russell K.
      The effect of concussion or mild traumatic brain injury on school grades, national examination scores, and school attendance: a systematic review.
      and the median return to work time for adults is 1-2 weeks,
      • Bloom B.
      • Thomas S.
      • Ahrensberg J.M.
      • et al.
      A systematic review and meta-analysis of return to work after mild traumatic brain injury.
      although 1 in 5 adults remain off work at 6 months post injury.
      • Bloom B.
      • Thomas S.
      • Ahrensberg J.M.
      • et al.
      A systematic review and meta-analysis of return to work after mild traumatic brain injury.
      There is little evidence for lasting objective impairment in cognition
      • Karr J.E.
      • Areshenkoff C.N.
      • Garcia-Barrera M.
      The neuropsychological outcomes of concussion: a systematic review of meta-analyses on the cognitive sequelae of mild traumatic brain injury.
      or academic performance.
      • Rozbacher A.
      • Selci E.
      • Leiter J.
      • Ellis M.
      • Russell K.
      The effect of concussion or mild traumatic brain injury on school grades, national examination scores, and school attendance: a systematic review.
      Girls and women may take longer to recover than boys and men, although this evidence is mixed.
      • Zemek R.
      • Barrowman N.
      • Freedman S.B.
      • et al.
      Clinical risk score for persistent postconcussion symptoms among children with acute concussion in the ED.
      ,
      • Iverson G.L.
      • Gardner A.J.
      • Terry D.P.
      • et al.
      Predictors of clinical recovery from concussion: a systematic review.
      • King N.S.
      A systematic review of age and gender factors in prolonged post-concussion symptoms after mild head injury.
      • Cnossen M.C.
      • van der Naalt J.
      • Spikman J.M.
      • et al.
      Prediction of persistent post-concussion symptoms following mild traumatic brain injury.
      History of prior mTBI(s)
      • Zemek R.
      • Barrowman N.
      • Freedman S.B.
      • et al.
      Clinical risk score for persistent postconcussion symptoms among children with acute concussion in the ED.
      ,
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • Howell D.R.
      • Zemek R.
      • Brilliant A.N.
      • Mannix R.C.
      • Master C.L.
      • Meehan W.P.
      Identifying persistent postconcussion symptom risk in a pediatric sports medicine clinic.
      ,
      • van der Naalt J.
      • Timmerman M.E.
      • de Koning M.E.
      • et al.
      Early predictors of outcome after mild traumatic brain injury (UPFRONT): an observational cohort study.
      and typical intracranial abnormalities on day-of-injury CT (eg, subdural hematoma)
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • Panenka W.J.
      • Lange R.T.
      • Bouix S.
      • et al.
      Neuropsychological outcome and diffusion tensor imaging in complicated versus uncomplicated mild traumatic brain injury.
      have been inconsistent predictors of clinical outcome. The more symptoms a patient has soon after mTBI, the more symptoms they tend to have weeks and months later
      • Iverson G.L.
      • Gardner A.J.
      • Terry D.P.
      • et al.
      Predictors of clinical recovery from concussion: a systematic review.
      ,
      • Cnossen M.C.
      • van der Naalt J.
      • Spikman J.M.
      • et al.
      Prediction of persistent post-concussion symptoms following mild traumatic brain injury.
      • Howell D.R.
      • Zemek R.
      • Brilliant A.N.
      • Mannix R.C.
      • Master C.L.
      • Meehan W.P.
      Identifying persistent postconcussion symptom risk in a pediatric sports medicine clinic.
      • van der Naalt J.
      • Timmerman M.E.
      • de Koning M.E.
      • et al.
      Early predictors of outcome after mild traumatic brain injury (UPFRONT): an observational cohort study.
      In adults, preinjury mental health problems and postinjury psychological distress (symptoms of depression and anxiety) are robust predictors of prolonged recovery.
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • Iverson G.L.
      • Gardner A.J.
      • Terry D.P.
      • et al.
      Predictors of clinical recovery from concussion: a systematic review.
      ,
      • Cnossen M.C.
      • van der Naalt J.
      • Spikman J.M.
      • et al.
      Prediction of persistent post-concussion symptoms following mild traumatic brain injury.
      ,
      • van der Naalt J.
      • Timmerman M.E.
      • de Koning M.E.
      • et al.
      Early predictors of outcome after mild traumatic brain injury (UPFRONT): an observational cohort study.
      ,
      • Cnossen M.C.
      • Winkler E.
      • Yue J.
      • Steyerberg E.W.
      • Lingsma H.
      • Manley G.
      Development of a prediction model for postconcussive symptoms following mild traumatic brain injury: a track-TBI pilot study.

      Treatment

      Early clinical management. Ruling out medical emergencies

      When a primary care provider sees a patient with suspected mTBI within the first 48 hours of injury and is the first medical professional to evaluate the patient, the top priority is to rule out a neurosurgical emergency (eg, expanding intracerebral hemorrhage). The potential for cervical spine injury should be investigated by assessing neck motion or tenderness to palpation of the boney vertebral elements, airway trauma, and sensory-motor deficits. Positive examination findings warrant immediate cervical spine stabilization and trauma evaluation.
      Acute neuroimaging of the brain should not be performed routinely following mild head trauma in previously healthy children and adults younger than 65 years old.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      However, patients with certain clinical red flags are at risk for actionable neuroimaging findings (fig 3). The Canadian CT head rule
      • Stiell I.G.
      • Wells G.A.
      • Vandemheen K.
      • et al.
      The Canadian CT Head Rule for patients with minor head injury.
      (or alternatives
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • King N.S.
      • Kirwilliam S.
      Permanent post-concussion symptoms after mild head injury.
      ) for adults and Pediatric Emergency Care Applied Research Network decision rule
      • Stiell I.G.
      • Clement C.M.
      • Rowe B.H.
      • et al.
      Comparison of the Canadian CT Head Rule and the New Orleans Criteria in patients with minor head injury.
      ,
      • Babl F.E.
      • Borland M.L.
      • Phillips N.
      • et al.
      Accuracy of PECARN, CATCH, and CHALICE head injury decision rules in children: a prospective cohort study.
      for children were developed to guide physicians in determining the need for urgent neuroimaging after mTBI. When the clinical indication for head CT is ambiguous, it is reasonable to counsel patients and their families on the benefits and risks (eg, radiation exposure).
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Adults older than 64 years and anticoagulated patients are at elevated risk for intracranial bleeding,
      • Minhas H.
      • Welsher A.
      • Turcotte M.
      • et al.
      Incidence of intracranial bleeding in anticoagulated patients with minor head injury: a systematic review and meta-analysis of prospective studies.
      leading to recommendations that they be routinely scanned with CT and/or admitted to hospital for observation.
      • Unden J.
      • Ingebrigtsen T.
      • Romner B.
      Scandinavian guidelines for the acute management of adult patients with minimal, mild, or moderate head injuries: an evidence and consensus-based update.
      ,
      • Stiell I.G.
      • Wells G.A.
      • Vandemheen K.
      • et al.
      The Canadian CT Head Rule for patients with minor head injury.
      Patients with skull fracture or trauma-related intracranial abnormalities on CT have nontrivial rates of clinical deterioration (11.7%), emergency neurosurgical intervention (3.5%), and death (1.5%), especially older adults and anticoagulated patients.
      • Marincowitz C.
      • Lecky F.E.
      • Townend W.
      • Borakati A.
      • Fabbri A.
      • Sheldon T.A.
      The risk of deterioration in GCS13-15 patients with traumatic brain injury identified by computed tomography imaging: a systematic review and meta-analysis.
      Signs of clinical deterioration such as reduced responsiveness, somnolence, severe and worsening headache, repeated vomiting, and emergence of focal neurologic signs warrant urgent evaluation at an emergency department.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Figure thumbnail gr3
      Fig 3Indications for urgent noncontrast computed tomography of the head after suspected mild traumatic brain injury. Abbreviation: MOI, mechanism of injury.
      • Stiell I.G.
      • Wells G.A.
      • Vandemheen K.
      • et al.
      The Canadian CT Head Rule for patients with minor head injury.
      ,
      • Kuppermann N.
      • Holmes J.F.
      • Dayan P.S.
      • et al.
      Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study.
      Blood-based biomarkers may have a role in preventing unnecessary CT imaging. The Scandinavian Neurotrauma Committee guidelines for adults
      • Unden J.
      • Ingebrigtsen T.
      • Romner B.
      Scandinavian guidelines for the acute management of adult patients with minimal, mild, or moderate head injuries: an evidence and consensus-based update.
      recommend that S100B values of <0.10 μg/L, if sampled within 6 hours of injury, can help rule out the need for CT in patients younger than 65 years with a Glasgow Coma Scale score of 14 or a Glasgow Coma Scale score of 15 with loss of consciousness or repeated vomiting. This approach has been empirically cross-validated.
      • Undén L.
      • Calcagnile O.
      • Undén J.
      • Reinstrup P.
      • Bazarian J.
      Validation of the Scandinavian Guidelines for Initial Management of Minimal, Mild and Moderate Traumatic Brain Injury in Adults.
      • Minkkinen M.
      • Iverson G.L.
      • Kotilainen A.-K.
      • et al.
      Prospective validation of the Scandinavian Guidelines for Initial Management of Minimal, Mild, and Moderate Head Injuries in Adults.
      • Ananthaharan A.
      • Kravdal G.
      • Straume-Naesheim T.M.
      Utility and effectiveness of the Scandinavian guidelines to exclude computerized tomography scanning in mild traumatic brain injury - a prospective cohort study.
      In early 2018, the United States Food and Drug Administration approved the Banyan Brain Trauma Indicator for adults with suspected mTBI, based on evidence that low values of C-terminal hydrolase-L1 (<327pg/mL) and glial fibrillary acidic protein (<22pg/mL) within 12 hours of injury are associated with very high probability (0.996) of negative head CT.
      • Bazarian J.J.
      • Biberthaler P.
      • Welch R.D.
      • et al.
      Serum GFAP and UCH-L1 for prediction of absence of intracranial injuries on head CT (ALERT-TBI): a multicentre observational study.
      C-terminal hydrolase-L1 and glial fibrillary acidic protein have not yet been incorporated into any published clinical practice guidelines. Their incremental value over clinical decision rules (eg, Canadian CT head rule
      • Stiell I.G.
      • Wells G.A.
      • Vandemheen K.
      • et al.
      The Canadian CT Head Rule for patients with minor head injury.
      ) is not yet known.
      The relationship between mTBI and epilepsy varies with injury severity. There may be no significantly increased risk following uncomplicated mTBI (concussion)
      • Wennberg R.
      • Hiploylee C.
      • Tai P.
      • Tator C.H.
      Is concussion a risk factor for epilepsy?.
      but likely more than a 2-fold increased risk in children and adults with cerebral contusions, hemorrhage, or skull fracture.
      • Keret A.
      • Bennett-Back O.
      • Rosenthal G.
      • et al.
      Posttraumatic epilepsy: long-term follow-up of children with mild traumatic brain injury.
      • Annegers J.F.
      • Hauser W.A.
      • Coan S.P.
      • Rocca W.A.
      A population-based study of seizures after traumatic brain injuries.
      • Christensen J.
      • Pedersen M.G.
      • Pedersen C.B.
      • Sidenius P.
      • Olsen J.
      • Vestergaard M.
      Long-term risk of epilepsy after traumatic brain injury in children and young adults: a population-based cohort study.
      Concussive convulsion, in which brief posturing or other seizure-like activity is observed immediately after impact (in 1%-2% of cases), is thought to result from a transient loss of cortical inhibition (ie, have a nonepileptogenic cause) and is not associated with prolonged recovery from mTBI or the development of posttraumatic epilepsy.
      • McCrory P.R.
      • Eerkovic S.F.
      Concussive convulsions incidence in sport and treatment recommendations.
      ,
      • Kuhl N.O.
      • Yengo-Kahn A.M.
      • Burnette H.
      • Solomon G.S.
      • Zuckerman S.L.
      Sport-related concussive convulsions: a systematic review.
      Routine seizure prophylaxis is not recommended in any mTBI clinical practice guideline.

      Education

      After critical medical complications are ruled out, the clinician should provide the patient (and family members and caregivers, if appropriate) with verbal and written education.
      • Gravel J.
      • D’Angelo A.
      • Carrière B.
      • et al.
      Interventions provided in the acute phase for mild traumatic brain injury: a systematic review.
      ,
      • Nygren-de Boussard C.
      • Holm L.W.
      • Cancelliere C.
      • et al.
      Nonsurgical interventions after mild traumatic brain injury: a systematic review. Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.
      Education should include an explanation of what an mTBI is, favorable expectations for recovery, and advice about how to manage specific symptoms.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      This information should be reviewed in subsequent visits as needed.

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      Quality patient-oriented education materials are available (
      • Maas A.I.
      • Menon D.K.
      • Adelson P.D.
      • et al.
      Traumatic brain injury: integrated approaches to improve prevention, clinical care, and research.
      ).

      Return to activity advice

      Relative rest for the first 24-48 hours after an mTBI is recommended
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Schneider K.J.
      • Leddy J.J.
      • Guskiewicz K.M.
      • et al.
      Rest and treatment/rehabilitation following sport-related concussion: a systematic review.
      ; the goal is to alleviate symptoms and reduce metabolic demands on the brain. Complete rest, such as lying in a dark room and avoiding all sensory stimuli (eg, reading, interacting with family and friends, etc) does not accelerate recovery and is therefore not advisable.
      • Silverberg N.D.
      • Iverson G.L.
      Is rest after concussion “the best medicine?”: recommendations for activity resumption following concussion in athletes, civilians, and military service members.
      ,
      • Schneider K.J.
      • Leddy J.J.
      • Guskiewicz K.M.
      • et al.
      Rest and treatment/rehabilitation following sport-related concussion: a systematic review.
      After an initial period of relative rest and symptom stabilization, patients should be encouraged to gradually resume normal daily activities (including screen time) as tolerated.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      This means that physical and cognitive activities can be progressively resumed at a pace that does not significantly worsen existing symptoms or generate new symptoms.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • Schneider K.J.
      • Leddy J.J.
      • Guskiewicz K.M.
      • et al.
      Rest and treatment/rehabilitation following sport-related concussion: a systematic review.
      Environmental conditions with high sensory stimulation can also be gradually reintroduced. Clinicians may provide more detailed, structured guidance for a graduated activity progression with return to school,
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      sport
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      (table 2), or military service.
      • McCulloch K.L.
      • Goldman L.S.
      • Lowe L.
      • et al.
      Development of clinical recommendations for progressive return to activity after military mild traumatic brain injury: guidance for rehabilitation providers.
      Students who are returning to school with residual symptoms may benefit from pragmatic accommodations
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      (table 3).
      Table 2Return to play progression
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      StageAimActivityGoal of Each Step
      1Symptom-limited activityUsual daily activities that do not provoke symptomsGradual reintroduction to school and work
      2Light aerobic exerciseWalking or stationary biking at slow to medium pace without resistance.Increase heart rate
      3Sport-specific exerciseAerobic exercises such as running, sprinting, skating. Sport-specific warm-up and light drills. No head impact activitiesIncrease motion
      4Noncontact training drillsMore intense training drills. May start progressive resistance training and weight liftingAssess coordination, fitness, and concentration
      5Full contact practiceParticipate in normal training activities including scrimmagingRestore confidence and assess functional skills by coaching staff
      6Return to sportNormal game play
      NOTE. There should be at least 24 h (or longer) for each step of the progression. If any symptoms worsen during exercise, the athlete should go back to the previous step.
      Table 3School accommodations
      • Iverson G.
      • Gioia G.
      Returning to school following sport-related concussion.
      ,
      • Gioia G.A.
      Medical-school partnership in guiding return to school following mild traumatic brain injury in youth.
      SymptomManifestationPossible Accommodations
      Decreased attention/poor concentrationHas trouble focusing during lessons and assignments.Advise a lighter work load with shorter/modified assignments. Provide written notes of lessons.
      Trouble rememberingStruggles holding instructions in mind, retaining information, and accessing new concepts. Trouble with reading comprehension and math calculations.Provide written instructions, shorter reading assignments, and offer smaller amounts of new material to learn.
      Decreased processing speedStruggles to keep up with work demands and processes information at a slower rate.Provide increased time for tests and/or assignments.
      Cognitive fatigueDecreased arousal.Provide breaks throughout day as needed.
      Emotional symptoms (eg, anxiety or depression)Increased social isolation or lack of interest in participating in usual activities (eg, sports, clubs).Provide encouragement to engage in social activities at school and outside of school. Suggest an appointment with a school counselor.
      HeadachesInterferes with ability to concentrate and perform school work.Breaks as needed in a quiet environment.
      Light or noise sensitivitySymptoms may worsen with screen time or in loud environments.Offer written assignments vs computer-based assignments. Avoid loud settings, such as cafeteria or assemblies.
      Symptom sensitivitySymptoms worsen with cognitive and/or physical exertion.Reduce cognitive or physical demands by providing rest breaks and completing work in small sections (ie, working to a point that does not elicit symptoms).
      To mitigate the risk of repeated mTBI, patients should be counseled to not return to activities that involve a relatively high risk head impact exposure (eg, collision sports) until they are clinically recovered.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      • Giza C.C.
      • Kutcher J.S.
      • Ashwal S.
      • et al.
      Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology.
      At present, there is no objective biomarker to determine mTBI resolution.
      • McCrea M.
      • Meier T.
      • Huber D.
      • et al.
      Role of advanced neuroimaging, fluid biomarkers and genetic testing in the assessment of sport-related concussion: a systematic review.
      Clinical recovery from mTBI is determined by symptom resolution, normalization of physical examination findings, and tolerance for usual daily activities (including vigorous exercise for athletes).
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      Objective tests of balance and cognition, such as in the Sport Concussion Assessment Tool–5th Edition (SCAT5)
      • Echemendia R.J.
      • Meeuwisse W.
      • McCrory P.
      • et al.
      Sport concussion assessment tool - 5th edition.
      for patients 13 years or older and the Child SCAT5
      • Davis G.A.
      • Purcell L.
      • Schneider K.J.
      • et al.
      The Child Sport Concussion Assessment Tool 5th Edition (Child SCAT5): background and rationale.
      for those 12 years and younger, can be used to supplement subjective symptom reporting and support return to play decision making with athletes.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      The balance and cognitive tests within the SCAT5 are most sensitive during the first 24 hours following injury but rapidly lose sensitivity to more subtle lingering deficits thereafter. Their utility for tracking recovery beyond 3-5 days after mTBI has not been established.
      • Echemendia R.J.
      • Broglio S.P.
      • Davis G.A.
      • et al.
      What tests and measures should be added to the SCAT3 and related tests to improve their reliability, sensitivity and/or specificity in sideline concussion diagnosis? A systematic review.
      In a setting without access to a neuropsychologist, return to play decisions should be made conservatively.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.

      Follow-up care for patients with persistent symptoms

      Patients who experience moderate-severe symptoms or are unable to promptly resume their usual activities (within 1-2 weeks for adults or 2-4 weeks for children and adolescents) require more active management.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      This section outlines strategies for more detailed assessment and treatment initiation for nonexpert clinicians to consider for the second clinic visit and beyond. Appropriate early intervention can mitigate symptom chronicity.

      Investigations

      Most practice guidelines discourage postacute neuroimaging in a typically recovering patient.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      However, it is reasonable to obtain an imaging study if symptoms are prolonged and are not improving over the course of weeks/months to rule out other contributors to the clinical presentation (eg, chronic subdural hematoma in an older adult).
      Clinicians should check for treatable causes of persistent dizziness, vision problems, sleep disturbance, and fatigue. For example, patients with persistent dizziness can be assessed for benign paroxysmal positional vertigo with the Dix-Hallpike maneuver or supine roll test.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Bhattacharyya N.
      • Gubbels S.P.
      • Schwartz S.R.
      • et al.
      Clinical practice guideline: benign paroxysmal positional vertigo (update).
      A screening ocular examination may identify impairments of saccades, smooth pursuit, convergence, or accommodation.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      • Matuszak J.M.
      • McVige J.
      • McPherson J.
      • Willer B.
      • Leddy J.
      A practical concussion physical examination toolbox: evidence-based physical examination for concussion.
      If fatigue does not improve with treatment of other symptoms, consideration should be given to alternative causes of fatigue (eg, adverse medication effects, sleep apnea, anemia, hypothyroidism), with limited investigations (eg, bloodwork for metabolic and electrolyte abnormalities) as needed.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Any evaluation of a patient with persistent symptoms following mTBI should include screening for anxiety and depression
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Makdissi M.
      • Schneider K.J.
      • Feddermann-Demont N.
      • et al.
      Approach to investigation and treatment of persistent symptoms following sport-related concussion: a systematic review.
      because mood symptoms are common after mTBI
      • McMahon P.
      • Hricik A.
      • Yue J.K.
      • et al.
      Symptomatology and functional outcome in mild traumatic brain injury: results from the prospective TRACK-TBI study.
      ,
      • Carlson K.F.
      • Kehle S.M.
      • Meis L.A.
      • et al.
      Prevalence, assessment, and treatment of mild traumatic brain injury and posttraumatic stress disorder: a systematic review of the evidence.
      ,
      • Emery C.A.
      • Barlow K.M.
      • Brooks B.L.
      • et al.
      A systematic review of psychiatric, psychological, and behavioural outcomes following mild traumatic brain injury in children and adolescents.
      and are among the most powerful predictors of prolonged recovery.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Iverson G.L.
      • Lange R.T.
      Examination of “postconcussion-like” symptoms in a healthy sample.
      Brief standardized self-report measures such as the Generalized Anxiety Disorder–7
      • Spitzer R.L.
      • Kroenke K.
      • Williams J.B.W.
      • Löwe B.
      A brief measure for assessing generalized anxiety disorder: the GAD-7.
      and Patient Health Questionnaire–9
      • Kroenke K.
      • Spitzer R.L.
      • Williams J.B.W.
      The PHQ-9: validity of a brief depression severity measure.
      can facilitate screening. The best available evidence suggests that the conventional cut-off scores on these measures (total score>10
      • Manea L.
      • Gilbody S.
      • McMillan D.
      A diagnostic meta-analysis of the Patient Health Questionnaire-9 (PHQ-9) algorithm scoring method as a screen for depression.
      ) do not require modification for mTBI.
      • Fann J.R.
      • Bombardier C.H.
      • Dikmen S.
      • et al.
      Validity of the Patient Health Questionnaire-9 in assessing depression following traumatic brain injury.
      Measures such as the Mood and Feelings Questionnaire
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      may be more appropriate for children. There is substantial overlap between mental health and post-mTBI symptoms. A positive screening test result should trigger a detailed psychiatric history and review of symptoms.
      Persistent subjective cognitive symptoms are often not associated with objective cognitive impairments. They can occur in the context of preexisting neurodevelopmental problems (eg, attention-deficit/hyperactivity disorder or learning disability) or present health conditions (eg, depression, pain, substance misuse) that carry substantial cognitive burden.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      ,
      • Broglio S.P.
      • Cantu R.C.
      • Gioia G.A.
      • et al.
      National Athletic Trainers’ Association position statement: management of sport concussion.
      ,
      • Theadom A.
      • Parag V.
      • Dowell T.
      • et al.
      Persistent problems 1 year after mild traumatic brain injury: a longitudinal population study in New Zealand.
      ,
      • Kristman V.L.
      • Côté P.
      • Yang X.
      • Hogg-Johnson S.
      • Vidmar M.
      • Rezai M.
      Health care utilization of workers’ compensation claimants associated with mild traumatic brain injury: a historical population-based cohort study of workers injured in 1997-1998.
      Patients who have activity-limiting cognitive symptoms beyond 1 month after mTBI may benefit from neuropsychological assessment to identify treatment recommendations and/or work or school accommodations.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.

      Symptom management: general approach

      Follow-up primary care should target specific symptoms.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Underlying this approach is an assumption that mTBI symptoms that persist past the acute period (2 weeks for adults and 4 weeks for school-aged children and adolescents) usually do not have a single etiology. Symptoms result from a complex interplay of biopsychosocial factors, many of which are not unique to mTBI. Two key principles guide treatment. First, treatment algorithms that have a substantial evidence base in primary medical or psychiatric disorders generally do not require modification to treat symptoms that occur after an mTBI.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Second, clinicians should prioritize the treatment of symptoms that are most amenable to intervention and most likely to bring about improvement in other symptoms. Priority symptoms in the subacute to chronic stage of mTBI recovery include headaches, insomnia, anxiety, and depression.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.

      Headaches

      Posttraumatic headaches do not have a unique location pattern or character but instead mimic primary headache types such as migraine, tension, cervicogenic, and those with mixed features.
      • Seifert T.
      • Evans R.
      Post-traumatic headache: a review.
      ,
      • Lucas S.
      • Hoffman J.M.
      • Bell K.R.
      • Dikmen S.
      A prospective study of prevalence and characterization of headache following mild traumatic brain injury.
      Early management should include avoidance of fasting (skipping meals) and maintaining adequate hydration. During the immediate postinjury period, acetaminophen may be preferred over aspirin and certain other nonsteroidal anti-inflammatory agents that confer a slightly increased risk of hemorrhagic stroke.
      • Ungprasert P.
      • Matteson E.L.
      • Thongprayoon C.
      Nonaspirin nonsteroidal anti-inflammatory drugs and risk of hemorrhagic stroke : a systematic review and meta-analysis of observational studies.
      Consider prescription medications when headaches are refractory to lifestyle interventions and occasional over-the-counter analgesics. Medication choice should be based on the primary headache type that the posttraumatic headache most closely resembles.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Algorithms for managing posttraumatic headaches are available for children
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      and adults.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Note that opioids, in almost all cases, should be avoided.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Medication overuse can perpetuate posttraumatic headache.
      • Gladstone J.
      From psychoneurosis to ICHD-2: an overview of the state of the art in post-traumatic headache.
      Excessive use of rescue pain medications (generally >10 days a month for opiates and triptans or >15 days a month for simple analgesics) for prolonged periods should be discouraged.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      The clinician can initiate a prophylactic bridge (eg, topiramate) along with advice to taper use of rescue medication (see here
      • Tepper S.J.
      • Tepper D.E.
      Breaking the cycle of medication overuse headache.
      ,
      • Diener H.C.
      • Holle D.
      • Solbach K.
      • Gaul C.
      Medication-overuse headache: risk factors, pathophysiology and management.
      for taper algorithms) and keep a daily headache diary (link to example diary) before referring to a specialist for medication overuse headache.
      • Diener H.C.
      • Holle D.
      • Solbach K.
      • Gaul C.
      Medication-overuse headache: risk factors, pathophysiology and management.

      Sleep disturbance

      Both hypersomnia and insomnia are common after mTBI. The goal of treatment is to normalize the sleep-wake cycle. Initial management of sleep disturbance should include environmental and behavioral modifications, such as setting a regular nighttime sleep schedule, limiting daytime naps, and avoiding foods or substances that may have a stimulating effect.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      If sleep disturbances become persistent, cognitive behavioral therapy is an evidence-based treatment option for primary insomnia.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Taylor D.J.
      • Pruiksma K.E.
      Cognitive and behavioural therapy for insomnia (CBT-I) in psychiatric populations: a systematic review.
      ,
      • Sullivan K.A.
      • Blaine H.
      • Kaye S.A.
      • Theadom A.
      • Haden C.
      • Smith S.S.
      A systematic review of psychological interventions for sleep and fatigue after mild traumatic brain injury.
      Sleep medications may help to normalize the sleep schedule but should only be used on a short-term basis while implementing behavioral strategies.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Commonly used medications include tricyclic antidepressants, trazodone, and melatonin. Benzodiazepines should be avoided.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Emergent obstructive sleep apnea, catalyzed by inactivity and weight gain after the injury, should be considered before treating insomnia in adults.

      Psychological distress

      Patients with severe depression or anxiety disorders should be referred to a mental health provider, but mild-moderate symptoms (eg, Generalized Anxiety Disorder–7 and Patient Health Questionnaire–9 screening scores both <15) can generally be managed within primary care.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Cognitive behavioral therapy and selective serotonin reuptake inhibitors are first line treatments for depression and anxiety disorders after mTBI.
      • Rao D.P.
      • Mcfaull S.
      • Thompson W.
      • Jayaraman G.C.
      Traumatic brain injury management in Canada: changing patterns of care.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Warden D.L.
      • Gordon B.
      • et al.
      Neurobehavioral Guidelines Working Group
      Guidelines for the pharmacologic treatment of neurobehavioral sequelae of traumatic brain injury.
      Alternative medications such as serotonin-norepinephrine reuptake inhibitors, tricyclics, trazodone, or mirtazapine may be appropriate, particularly if treating concurrent symptoms such as sleep disturbance, headache, or bodily pain. Several of these agents have antiheadache properties, extending their usefulness. Benzodiazepines for anxiety should be avoided.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      In general, treatment should be initiated as soon as a patient meets diagnostic criteria for a mental health disorder (eg, ≥2 weeks of persistent depressive symptoms for major depressive disorder), and effective pharmacotherapy should be maintained for at least 6 months before considering discontinuation.

      Exercise as treatment

      Physical activity has pan-domain beneficial effects. Following an initial brief period symptom subsidence, aerobic exercise at insufficient intensity and duration to provoke symptoms appears safe and therapeutic.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Schneider K.J.
      • Leddy J.J.
      • Guskiewicz K.M.
      • et al.
      Rest and treatment/rehabilitation following sport-related concussion: a systematic review.
      ,
      • Lal A.
      • Kolakowsky-Hayner S.A.
      • Ghajar J.
      • Balamane M.
      The effect of physical exercise after a concussion: a systematic review and meta-analysis.
      The preinjury activity level of the patient should be considered in making exercise recommendations, but the clinician could recommend 20 minutes of aerobic exercise 5-6 times a week, initially at light intensity (no more than [220−age]×0.7 heart beats per minute) and supervised (eg, by a physical therapist) and then at home.
      • Leddy J.
      • Hinds A.
      • Sirica D.
      • Willer B.
      The role of controlled exercise in concussion management.

      Referral to a specialty clinic

      The majority of patients with mTBI can be managed effectively in primary care and need not be referred to a specialty clinic.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      Referral to individual medical specialists or to a specialized multidisciplinary mTBI clinic is appropriate for patients with persistent symptoms (lasting more than 4-6 weeks) that do not respond to treatment in a primary care setting.
      Veterans Affairs/Department of Defense
      Management of Concussion-Mild Traumatic Brain Injury (MTBI) Clinical Practice Guidelines.
      • Lumba-Brown A.
      Centers for Disease Control and Prevention Guideline on the Diagnosis and Management of Mild Traumatic Brain Injury Among Children.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      Earlier referral may be helpful when (1) patients have a high symptom burden or known risk factors for prolonged recovery, such as a preexisting mental health disorder,
      • Silverberg N.D.
      • Gardner A.
      • Brubacher J.R.
      • Panenka W.
      • Li J.J.
      • Iverson G.L.
      Systematic review of multivariable prognostic models for mild traumatic brain injury.
      ,
      • Iverson G.L.
      • Gardner A.J.
      • Terry D.P.
      • et al.
      Predictors of clinical recovery from concussion: a systematic review.
      (2) patients are unable to progress with their return to activity or are attempting to return to high-stakes roles soon after injury (eg, competitive sport or university examinations), or (3) access to care is limited (eg, long waitlist times). mTBI clinics should have access to a physician and a multidisciplinary team of licensed health professionals who provide coordinated, evidence-based care.

      Ontario Neurotrauma Foundation standards for post-concussion care. 2019. Available at: http://onf.org/documents/standards-for-post-concussion-care. Accessed June 11, 2018.

      Interdisciplinary treatment may include vestibular, vision-oculomotor, behavioral health, and cognitive rehabilitation interventions
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      ,
      Ontario Neurotrauma Foundation
      Guidelines for Concussion/Mild Traumatic Brain Injury & Persistent Symptoms.
      ,
      • Cooper D.B.
      • Bunner A.E.
      • Kennedy J.E.
      • et al.
      Treatment of persistent post-concussive symptoms after mild traumatic brain injury: a systematic review of cognitive rehabilitation and behavioral health interventions in military service members and veterans.
      • Cicerone K.D.
      • Langenbahn D.M.
      • Braden C.
      • et al.
      Evidence-based cognitive rehabilitation: updated review of the literature from 2003 through 2008.
      • Echemendia R.J.
      • Giza C.C.
      • Kutcher J.S.
      Developing guidelines for return to play: consensus and evidence-based approaches.
      that are individually tailored to a patient’s symptom profile.
      • Collins M.W.
      • Kontos A.P.
      • Okonkwo D.O.
      • et al.
      Statements of agreement from the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.
      Patients with 1-2 specific symptoms may only require individual disciplines rather than referral to a multidisciplinary clinic. For example, patients with primarily vestibular symptoms should be referred to physical therapy or otolaryngology.
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.
      Musculoskeletal cervical complaints may respond to multifaceted physical therapy.
      • Schneider K.J.
      • Leddy J.J.
      • Guskiewicz K.M.
      • et al.
      Rest and treatment/rehabilitation following sport-related concussion: a systematic review.

      Pediatric considerations

      There is expert consensus that management of school-aged children and adolescents with mTBI should consider that (1) recovery time might be slower than adults,
      • Kuhl N.O.
      • Yengo-Kahn A.M.
      • Burnette H.
      • Solomon G.S.
      • Zuckerman S.L.
      Sport-related concussive convulsions: a systematic review.
      ,
      • Giza C.C.
      • Kutcher J.S.
      • Ashwal S.
      • et al.
      Summary of evidence-based guideline update: evaluation and management of concussion in sports.
      (2) child-validated symptom rating scales and assessment tools, such as the Child SCAT5
      • Davis G.A.
      • Purcell L.
      • Schneider K.J.
      • et al.
      The Child Sport Concussion Assessment Tool 5th Edition (Child SCAT5): background and rationale.
      are most appropriate, (3) return to activity advice to prevent reinjury should include nonsport play,
      • Haarbauer-Krupa J.
      • Arbogast K.B.
      • Metzger K.B.
      • et al.
      Variations in mechanisms of injury for children with concussion.
      especially in unpredictable environments (eg, schoolyard), and (4) successful return to school (ie, symptom-free during school activities with no accommodations) should precede return to sport.
      • McCrory P.
      • Meeuwisse W.
      • Dvorak J.
      • et al.
      Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016.
      ,
      Ontario Neurotrauma Foundation Guidelines Diagnosing and Managing Pediatric Concussion.

      Study limitations

      Narrative reviews have important limitations. The clinical practice guidelines and consensus statements we drew from had already conducted systematic searches and critical appraisals of the available evidence. We therefore considered the risk of including recommendations that were not supported by evidence or expert consensus opinion to be low. However, it is possible that author bias resulted in an incomplete or imbalanced synthesis of management recommendations. The narrower list of recommendations in table 1 represents the clinical actions with the most consistent support across statements or guidelines, as determined by independent extractors.

      Conclusions

      Clinicians without a specialty practice in mTBI are increasingly involved in providing and coordinating care for patients with mTBI. Careful diagnostic assessment and proactive clinical management is essential to maximizing recovery. Patient education, return to activity guidance, and symptom-targeted treatment are pillars of mTBI management in primary care.

      Acknowledgments

      Other members of the American Congress of Rehabilitation Medicine Mild TBI Task Force were collaborators on this article: Alison M. Cogan, PhD, OTR/L, Washington DC Veterans Affairs Medical Center; Min Jeong Park Graf, MD, University of Minnesota Medical School & Department of Physical Medicine and Rehabilitation, Hennepin Healthcare; Maria Kajankova, PhD, Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai & Brain Injury Research Center; Gary McKinney, MHSc, CBIS, CPT, Defense and Veterans Brain Injury Center; Christina Weyer Jamora, PhD, RN, Department of Neurological Surgery, University of California San Francisco & Department of Psychiatry, Zuckerberg San Francisco General Hospital, University of California San Francisco.
      The authors wish to thank primary care providers Sarah Shaw, MD, CCFP (Toronto, Canada), and Vivienne Lemos, MD, CCFP (Toronto, Canada), for providing helpful feedback from a user perspective on an early manuscript draft.
      The American Congress of Rehabilitation Medicine Brain Injury Special Interest Group provided administrative support for the activities of the Task Force and funded the open access fees for this article through a Task Force grant.

      Supplementary data

      References

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