Diagnosis of mTBI/concussion is the critical first step in successful management, leading to improved outcomes and prevention of further injury. This requires a high index of suspicion in situations of increased risk of mTBI concussion such as playing contact sport; here, any person suspected of a possible mTBI/concussion should be removed of play to avoid the risk of re-injury.
The initial medical assessment aims to establish a diagnosis of mTBI/concussion by ruling out other conditions with similar symptom profiles, such as more severe forms of traumatic brain injury, cervical spine injuries and some medical and neurological and mental health conditions.
Not all people who experience mTBI/concussion will present to the emergency department, with many presenting to primary care. Regardless of setting, assessment should be carried out by an appropriately qualified health professional.
1 EBRS Suspected mTBI/concussion should be recognised as soon as possible. Adapted i CBR Adults and children with suspected mTBI/concussion should be referred to an appropriately qualified health professional for confirmation of diagnosis. Adapted In light of the limited evidence on pre-hospital tools that specifically determine the need for assessment in the acute hospital setting following mTBI/concussion, the following consensus-based recommendations for adults and children were informed by the Canadian CT Head Rule and the Pediatric Emergency Care Applied Research Network study. These are identified as “red flags” in concussion recognition tools. Additional considerations apply for elderly adults due to the likely presence of comorbidities.
ii CBR People with mTBI/concussion should be assessed in a hospital setting if the mechanism of injury was severe1 or if they develop the following signs or symptoms within 72 hours of injury:
– seizure or convulsion
– loss of consciousness
– deteriorating level of consciousness
– confusion
– not acting normally, including abnormal drowsiness, increasing agitation, restlessness or combativeness
– double vision, ataxia, clumsiness or gait abnormality
– weakness and tingling in arms or legs
– vomiting2
– presumed skull fracture (palpable fracture, ‘raccoon eyes’ or Battle’s signs, cerebrospinal fluid leak, otorrhea, rhinorrhoea)
– severe headache (children 2-18 years)
– occipital or parietal or temporal scalp haematoma (in children aged less than 2 years only)3Adapted Notes:
1 Severe mechanism of injury: motor vehicle accident with patient ejection, death of another passenger or rollover; pedestrian or bicyclist without helmet struck by motorised vehicle; falls of 1 metre or more for children aged less than 2 years, and more than 1.5 m for children aged 2 years or older; or head struck by a high-impact object.
2 A case of a single isolated vomit can be assessed in general practice.iii CBR Children with head injuries sustained from ground-level falls or walking or running into stationary objects, with no loss of consciousness, a GCS score of 15 and no signs or symptoms of head trauma other than abrasions, do not need to attend hospital for assessment; they can be safely managed in primary care or at home. Adapted iv CBR Special consideration needs to be made for elderly people who:had a fall/head trauma (witnessed or unwitnessed) or explicit significant injuryare on anticoagulation/antiplatelet therapy with the above incidents.Further assessment and CT of the brain should be considered. New Physical examination looks for objective signs of disorientation, amnesia or other dysfunction following mTBI/concussion and examines for other potential diagnoses. Mental health status should also be reviewed as there is evidence that pre-injury psychiatric history or disorder is a predictor of persisting post-concussion symptoms and disability following mTBI/concussion.
2 EBRS An appropriately qualified health professional should conduct a review of every person who has sustained mTBI/concussion to confirm diagnosis. Adapted A thorough assessment of a person with mTBI/concussion should be carried out by an appropriately qualified health professional to both assess the condition and to exclude potential neurosurgical or medical complications. The examination should include:
- pre-injury history (e.g. prior concussion(s), premorbid conditions and medications)
- concurrent potential factors that could exacerbate symptoms or prolong recovery (e.g. comorbid medical conditions, Attention-deficit/hyperactivity disorder [ADHD], mental health difficulties, impact of associated concurrent injuries), migraine
- evaluation of current signs and symptoms
- consideration of all available diagnostic tests (if performed)
- evaluation of potential associated physical injuries through examination (e.g. neck injury).
3 EBRC Initial medical management of a person with mTBI/concussion should be based on a thorough history and physical examination, and concurrent potential contributing factors, such as co-morbid medical conditions and mental health conditions Adapted 4 EBRC Consideration should be given to use of an age-appropriate standardised concussion symptom inventory tool. Adapted Computed tomography (CT) scanning is an appropriate investigation for the exclusion of neurosurgically significant lesions (e.g. haemorrhage) in the acute phase (≤48 hours after injury) but not in the post-acute phase (>48 hours after injury).
People with bleeding disorders or who are taking direct oral anticoagulant treatment or a vitamin K antagonist require extra attention as they have an increased risk of haemorrhage. People with neurodevelopmental disabilities sustain more injuries than those without and also require special consideration as neurological deterioration can be harder to assess.
Imaging protocols are beyond the scope of this guideline. For guidance on imaging for children, please see PREDICT recommendations 24, 25 and 26.
5 EBRC Neuroimaging should not be routinely used for the purpose of diagnosing mTBI/concussion. Adapted 6 EBRC In children with mTBI/concussion who have one or more risk factors for a brain injury, health care professionals should take into account the number, severity and persistence of signs and symptoms (see Table 1 and Appendix C), and family factors (e.g. distance from hospital and social context) when choosing between structured observation and a head CT. Adopted 7 EBRC The need for neuroimaging of people with mTBI/concussion on acute presentation (within 24-48 hours post-injury) should be determined according to the Canadian CT rule (see Table 2), noting that people who are anticoagulated or who have bleeding disorders require extra consideration. Adapted v CBR Plain skull x-rays are not recommended for the purpose of diagnosing mTBI/concussion. Adapted vi CBR Health professionals should not use single-photon emission CT (SPECT) or quantitative electroencephalogram in the acute evaluation of suspected or diagnosed mTBI/concussion. Adopted 8 EBRS After a normal initial head CT in people presenting to an acute care setting following mTBI/concussion, neurological deterioration should prompt urgent reappraisal, with consideration of an immediate repeat head CT and consultation with a neurosurgical service. Adapted 9 EBRS People who are being observed after a normal initial head CT who have not achieved a GCS score of 15 after up to 6 hours observation from the time of injury, should have senior clinical review for consideration of a further head CT or MRI and/or consultation with a neurosurgical service. The differential diagnosis of neurological deterioration or lack of improvement should take account of other injuries, drug or alcohol intoxication and non-traumatic aetiologies. Adapted Notes:
1 The initial head CT should be interpreted by a radiologist to ensure no injuries were missed.
2 Measured using an age-appropriate GCS, consider post-traumatic amnesia assessment for those that remain amnesic.Table 1: Pediatric Emergency Care Applied Research Network (PECARN) Head Injury Decision Rule
Risk factors for intracranial injury All children
– GCS 14 or other signs of altered mental status
– Abnormal neurological examination
– Severe mechanism of injury*
– Post-traumatic seizuresAge <2 years
– Palpable skull fracture
– Non-frontal scalp haematoma
– History of loss of consciousness ≥5 seconds
– Acting abnormally per parentAge >2 years
– Signs of base of skull fracture
– History of loss of consciousness
– History of vomiting**
– Severe headacheAny risk factors: Recommended observation period is up to 4 hours post injury including 1 hour return to normal High risk = imaging Intermediate risk = consider imaging or structured observation Low risk Very low risk – Palpable skull fracture OR
– Signs of base of skull fracture OR
– Worsening signs or symptoms OR
– Persistent GCS 14 OR
– Persistent signs of altered mental status– ≥ 2 risk factors OR
– Post-traumatic seizure(s) OR
– Persistent severe headache or persistent vomiting >4 hours post injuryNot intermediate or high risk AND improving signs and symptoms: GCS 15, acting normally, no current signs of altered mental status, vomiting has stopped, severe headache resolved No risk factors Notes: See also Appendix C.
* Struck by a motor vehicle, occupant ejected from a motor vehicle or death of another passenger, motor vehicle rollover; bicyclist without helmet struck by motorised vehicle; falls of 1 m or more for children aged less than 2 years and more than 1.5 m for children aged 2 years or older; or head struck by a high-impact object).
** Isolated vomiting, without any other risk factors, is an uncommon presentation of more severe forms of traumatic brain injury. Vomiting, regardless of the number of vomits or persistence of vomiting, in association with other risk factors increases concern for more severe forms of traumatic brain injury.
Source: Adapted from PREDICT and Kuppermann N, Holmes JF, Dayan PS, Hoyle JD, Jr., Atabaki SM, Holubkov R, et al. Identification of Children at Very Low Risk of Clinically-Important Brain Injuries after Head Trauma: A Prospective Cohort Study. Lancet. 2009;374(9696):1160–70.
Table 2: The Canadian CT Head rule for adults with mTBI/concussion
– Signs of basal skull fracture
– Haemotympanum, ‘racoon’ eyes, CSF otorrhoea/rhinorrhoea, Battle’s sign
– Dangerous mechanism
– Pedestrian struck by vehicle
– Occupant ejected from motor vehicle
– Fall from elevation ≥3 metres or 5 stairsCT head is only required for people with minor head injury with any one of these findings: Rule not applicable if:
– Non-trauma cases
– GCS <13
– Age <16 years
– Anticoagulants or bleeding disorder
– Obvious open skull fractureHigh risk (for neurological intervention)
1. GCS score <15 at 2 hours after injury
2. Suspected open or depressed skull fracture
3. Any sign of basal skull fracture*
4. Vomiting ≥2 episodes
5. Age ≥65 yearsMedium risk (for brain injury on CT)
6. Amnesia before impact ≥30 min
7. Dangerous mechanism **Source: Stiell IG, Wells GA, Vandemheen K, Clement C, Lesiuk H, Laupacis A, et al. The Canadian CT Head Rule for patients with minor head injury. Lancet. 2001;357(9266):1391-6. doi: 10.1016/s0140-6736(00)04561-x.
Simple linear skull fractures do not require specific intervention if a head CT reveals no underlying injury. A meta-analysis and four retrospective studies found a very low risk of adverse outcomes in children with isolated, non-displaced, linear skull fractures. Evidence on the level of risk for adverse outcomes in people aged >12 with mTBI (GCS 13–15) and injuries identified by head CT is limited, but 27.7% may require hospital admission and 13% neurosurgery, intensive care admission or intubation. Risk factors for deterioration include anticoagulation, GCS<15, abnormal neurological examination, and significant extracranial injury. Evidence of intracranial injury or intracranial haemorrhage on head CT requires urgent neurosurgical consultation.
vii CBR Consultation with a neurosurgical service should occur in all cases with an intracranial injury shown on a head CT, other than in infants and children with an isolated, non-displaced, linear skull fracture on a head CT without intracranial injury and a GCS score of 15. Adopted viii CBR Consultation with a neurological services should occur in all adults with a base of skull fracture, or skull fracture and confusion, decreased conscious level, or neurological symptoms or signs. Adapted Notes:
1 Measured using an age-appropriate GCS e.g. for infants and non-verbal people.People with a simple linear skull fracture on head CT should be observed for 4 to 6 hours in hospital or the emergency department. People are admitted for observation if there is any suspicion or clinical evidence of a more severe brain injury. Structured observation is appropriate in people who do not fulfil criteria for routinely available imaging and necessary in those requiring transfer to access appropriate imaging.
a PP Where structured observation is undertaken, observation period should be 4 hours or greater and should include amnesia and orientation assessment. Adapted b PP If the GCS does not return to 15, repeat assessment should be performed. Adapted c PP Discharge criteria should be met, even if there is a normal head CT. Adapted
d PP Consider the possibility of abusive head trauma in all presentations of mTBI/concussion. Adapted e PP In people with a ventricular shunt and mTBI/concussion, if there are local signs of shunt disconnection, shunt fracture (e.g. palpable disruption or swelling), or signs of shunt malfunction, consider obtaining a shunt series, and consultation with a neurosurgical service. Adapted Adults taking anticoagulant or antiplatelet therapies who have a mild head injury are at an increased risk of intracranial haemorrhage and delayed neurological deterioration (up to 6 hours). People without symptoms and a GCS of 15 may not need a head CT and instead undergo structured observation. However, elderly people (>60 years) are at higher risk of intracranial haemorrhage and have a higher mortality, thus elderly patients on anticoagulant or antiplatelet therapy should be considered for a CT scan. Evidence on the risk of important intracranial injuries in children with bleeding disorders compared to those without bleeding disorders is limited. It is likely that the risk of intracranial haemorrhage differs between types of bleeding disorders and types of anticoagulant or antiplatelet therapy.
Urgent anticoagulant reversal should be considered for people with acute intracranial haemorrhage, as ongoing bleeding and hemorrhage enlargement can cause neurologic deterioration, elevation in intracranial pressure, and poor functional outcome or death. Urgent reversal may not be necessary for a clinically stable person with a small, chronic subdural hemorrhage and no evidence of elevated intracranial pressure. Here, the potential benefit of reversing anticoagulation must be weighed against the risk of thrombosis/stopping the anticoagulation.
10 EBRC For people with congenital or acquired bleeding disorders who have experienced mTBI/concussion, consider structured observation over immediate head CT if there are no risk factors for more serious forms of traumatic brain injury (see Box A, 1.5.1) and no symptoms consistent with intracranial bleeding. If there is a risk factor for intracranial injury, a head CT should be performed. If there is a deterioration in neurological status, a head CT should be performed urgently. Adapted f PP For people with a coagulation factor deficiency (e.g. haemophilia) who have experienced mTBI/concussion that results in presentation to an acute care setting, neuroimaging should not delay the urgent administration of replacement factor, with guidance from a haematologist sought as required. Adapted g PP For children with a bleeding disorder or on anticoagulant or antiplatelet therapy who have experienced mTBI/concussion that results in presentation to an acute care setting, health professionals should urgently seek advice from a haemoatologist. Adapted h PP In adults on anticoagulant or antiplatelet therapy or who have known bleeding disorders, CT should be strongly considered. Health professionals should follow local protocols and guidelines for management of anticoagulation agents in trauma patients. New Neurodevelopmental disorders, such as attention deficit/hyperactivity disorder (ADHD) and specific learning disorder (LD) may increase the risk of bodily injury, including mTBI/concussion, over the lifetime in both males and females.95
ix CBR It is unclear whether people with neurodevelopmental disorders have a different background risk for intracranial injury following mTBI/concussion. Consider performing a period of structured observation or a head CT because these people may be difficult to assess. Shared decision making with caregivers and the clinical team that knows the person is particularly important. Adapted x CBR In people who are intoxicated with drugs or alcohol who have experienced mTBI/concussion, treat as if the neurological findings are due to the mTBI/concussion. A low threshold should be used to recommend head CT. Brain imaging decision rules may not have adequate sensitivity for this group. Adapted