Information for medical practitioners to help recognise the symptoms of concussion and understand the best process for treatment and ongoing management of concussion.
"The diagnosis of concussion requires a careful assessment covering several domains including the history of the trauma, the athlete symptoms..."
David hughes, AIS chief medical officer
What is concussion?
Concussion is a type of brain injury. It is a complex injury that is challenging to evaluate and manage. The Concussion in Sport Group (CISG) international Consensus Statement defines concussion as ‘a traumatic brain injury, induced by biomechanical forces’. It generally results from a knock to the head, face or neck - but may be anywhere on the body which transmits force to the head. Concussion involves short-lived impairment of neurological function. Concussion is an evolving injury that may change over the first few hours or over a few days. In most adult cases, symptoms are resolved within 14 days of injury.
Assessment of concussion
Diagnosing concussion can be difficult - but is critical to correctly managing and preventing further injury.
Diagnosis relies on the clinical assessment of symptoms and signs. There is no specific diagnostic test which confirms the presence or otherwise of concussion.
For Adults: Medical practitioners can use the Concussion in Sport Group Sport Concussion Assessment Tool 5 (SCAT5) as part of an overall clinical assessment to assess potential concussions.
For Children: The Child Sport Concussion Assessment Tool (Child-SCAT5) can be used to assess concussion in children aged 5 – 12 years.
People without medical training can use the Concussion Recognition Tool, also developed by the Concussion in Sport Group.
Signs and symptoms
If an athlete displays these symptoms/signs they may have a more serious injury. They should be immediately taken to the nearest emergency department.
First-aid principles still apply for athletes suspected of having a concussion. Responders should systematically assess the airway, breathing, circulation, disability and exposure of the athlete in all situations.
Cervical spine injuries should be suspected if there is any loss of consciousness, neck pain or a mechanism that could lead to spinal injury. Until a cervical spine injury can be ruled out, undertake manual inline stabilisation and apply a hard collar.
In diagnosing concussion, medical practitioners should do a clinical history and examination that includes:
- mechanism of injury
- symptoms and signs
- cognitive functioning
- neurological assessment including balance testing
- a completed concussion assessment using the SCAT5 for adults or Child-SCAT5 for children aged 5 – 12 years
As part of the assessment medical practitioners may use:
- Computerised neurocognitive testing. Pre-season baseline neurocognitive testing is useful to compare against post-injury scores. Program reference ranges that can be applied in the absence of a baseline test.
- Medical imaging where there is suspicion of serious head or brain injury.
Currently, no serum biomarkers assist in the diagnosis of concussion. Blood tests and medical imaging is not indicated in the diagnosis or management of uncomplicated concussion.
Medical practitioners often have athletes present to the clinic during the week, having suffered a potential concussion over the previous weekend. This poses challenges. If there is any suspicion that a concussion occurred on the weekend, the medical practitioner should assume that a concussion did in fact occur. There is no test or series of tests which can conclude that a concussion did not occur.
Six key video review steps for the team clinician
Video technology is used by many professional sports to support identification of concussion, differentiate between mandatory and discretionary concussion signs and, in some instances, assist with return to sport decisions. The 2017 Berlin Concussion in Sport Group Consensus Statement identifies six steps for video-review focused on concussion identification.
Six key video-review steps for the team clinician
- Look for the suspected head impact event
- Look for the immediate response of the injured athlete (0-2 s). Does the athlete fall to the ground? If the athlete falls, is there loss of head and neck control? Does the athlete protect himself/herself when falling? If the athlete remains upright, is he/she steady on his/her feet?
- Look for the subsequent response (2-5 s). If the athlete falls, does he/she move spontaneously? Is there evidence of purposeful voluntary movement (ie, placing the ball or completing a tackle)? Is there evidence of a concussive convulsion or tonic posturing? How does the athlete respond to the attending medical staff (this phase may extend for substantially longer than 5 s, particularly if in-line cervical immobilisation is required)? If the athlete remains standing, the distinction between the subsequent and late responses may be unclear.
- Watch for the athlete’s late response when returning to his/her feet (if the athlete has fallen). Is the athlete unsteady when attempting to get to his/her feet and return to sport? Does the athlete need help from others to stand up? Are the athlete’s movements fluid and coordinated? Does the athlete fall to the ground?
- Watch the athlete’s behaviour on return to sport. Are his/her actions appropriate or not? Does he/she move immediately to the correct position on the field of play?
- Observe the responses of other athletes and match officials.
Minimum criteria for removal from sport
Any athlete with suspected concussion should be REMOVED FROM SPORT, medically assessed and monitored for deterioration. No athlete diagnosed with concussion should be returned to play on the day of injury.
Minimum criteria for diagnosing concussion are:
- A thorough assessment looking at loss of consciousness, symptoms, cognition, neurobehavioural symptoms, and balance – with any abnormality being a potential sign of concussion.
- A concussion assessment using the SCAT5 for adults or Child-SCAT5 for children aged 5 – 12 years. Note: the diagnostic utility of the SCAT decreases 3-5 days post-concussion.
How to manage concussion
Any athlete with suspected or confirmed concussion should:
- remain in the company of a responsible adult
- not be allowed to drive
- be advised to avoid alcohol
- have their medications reviewed.
Specifically, concussed athletes should avoid:
- anti-inflammatories (such as ibuprofen, diclofenac or naproxen),
- sleeping tablets
- sedating pain medications.
If the athlete is diagnosed with concussion, immediate management is physical and cognitive rest. This may include time off school or work, and relative rest from cognitive activity. Having rested for 24 – 48 hours after sustaining a concussion, the athlete can begin moderate intensity physical activity - as long as the activity doesn’t cause significant and sustained deterioration in symptoms. Concussive symptoms usually resolve in 10 – 14 days.
Children and adolescents
Sport-related concussions are common in children and adolescents aged 18 years or younger. For this age group, a more conservative approach to diagnosis and management is recommended. This is because this age group:
- has a slower rate of recovery from concussion
- has unique physical, cognitive and emotional differences
- is more vulnerable to concussion, due to factors including decreased myelination, poor cervical musculature, and (possibly) increased head to neck ratio
- the role of cerebral blood flow alterations in the pathophysiology of concussion may be more significant
Return to learn
‘Return to learn’ is about the athlete’s gradual return to their usual program at school or work.
‘Return to learn’ should take priority over ‘Return to sport’. School programs may need to include more regular breaks, rests and increased time to complete tasks.
Medical practitioners can use the Return to Learn Care Plan to communicate to teachers the requirements for a concussed child or adolescent.
Return to sport
‘Return to sport’ is about the athlete’s gradual return to full sporting activity.
Having rested for 24 – 48 hours after sustaining a concussion, the patient can begin moderate intensity physical activity - as long as the activity doesn’t cause significant and sustained deterioration in symptoms. Concussive symptoms usually resolve in 10 - 14 days, after which the athlete can begin a staged return to sport.
Athletes returning to sport should follow these steps and spend at least 24 hours at each level:
Begin with light aerobic activity (at an intensity that can easily be maintained whilst having a conversation) until symptom-free
Basic sport-specific drills which are non-contact and with no head impact
More complex sport-specific without contact, including resistance training
Full contact practice following medical review
Normal competitive sporting activity
Athletes should only progress to the next level when they have completed 24 hours at the current level without recurrence of symptoms. If symptoms recur or worsen, athletes should step down to the previous level and complete at least 24 hours symptom free at that level..
Medical practitioners can use these Return to sport protocols to inform their Return to sport patient programs.
Predictors of clinical recovery
Predictors of clinical recovery can assist the medical practitioner in managing the concussed athlete. These predictors are associated with protracted recovery:
- high severity of acute and subacute concussive symptoms
- a high number of concussive symptoms
- prolonged loss of consciousness (longer than one minute)
- post-concussive seizure
- previous history of concussion
- age of the athlete
- female sex
- history of depression, anxiety or migraine.
Mental health and concussion
There is a potential link between mental illness and concussion, although the relationship is not clear. Athletes with a history of mental illness require a more cautious approach. A conservative Return to Sport strategy is recommended.
Chronic Traumatic Enceophalopathy
Chronic traumatic encephalopathy (CTE), particularly in retired athletes from the National Football League in the USA, has received significant media attention.
CTE can only be diagnosed by post-mortem observation, and it is described by McKee et al 2009 as a ‘progressive neurodegeneration clinically associated with memory disturbances, behavioural and personality change, Parkinsonism, and speech and gait abnormalities’.
Neuropathological criteria for the diagnosis of CTE has recently been defined to be the abnormal accumulation of hyperphosphorylated tau protein in the brain.
Properly designed prospective studies, which control for potential confounding variables, are required to improve our understanding of CTE and any potential link to prior concussion.
- Some researchers have presented preliminary evidence that repeated head trauma causes the condition, but there is significant selection bias in many of the reported cases.
- The link between sport-related concussion and CTE is based on low-level evidence. Research is limited to case reports, case series and retrospective analyses which cannot adequately determine causality or risk factors.
- The potential contribution of confounders, such as genetic predisposition, psychiatric illness, alcohol and drug use or co-existing dementia, is not adequately accounted for in the current literature.
- While there is significant concern about CTE and its possible relationship with concussion, it is important to note that no causative link has been clearly established.
Acute cerebral oedema
Acute cerebral oedema or ‘second impact syndrome’ has received media attention due to its catastrophic outcomes. Acute cerebral oedema refers to rapid cerebral swelling that can occur when a second concussive injury is sustained during a ‘vulnerable’ period when the brain has not recovered from an initial insult. Animal models have demonstrated that there is a period of vulnerability during which further injury can result in significant axonal injury with associated ion channel damage. It is thought that a second impact may not be needed for the swelling to develop.
The condition is rare and the only available literature consists of case studies which are inadequate to provide a good understanding of the mechanisms and risk factors. Further research is needed to better understand the pathophysiology and risk factors for ‘second impact syndrome’.
- Concussion Management Flow Chart for Medical Practitioners - On Field(PDF • 281.5 kb)
- Concussion Management Flow Chart for Medical Practitioners - Off Field(PDF • 275.4 kb)
- SCAT5 – Sport Concussion Assessment Tool
- ChildSCAT5 – Sport concussion Assessment Tool for children
- Implementation of the 2017 Berlin Concussion in Sport Group Consensus Statement in contact and collision sports
- AIS-AMA position statement on concussion in sport
- AIS-AMA position statement on concussion in sport - update
- Return to Sport Protocol for Children(PDF • 282.3 kb)
- Return to Sport Protocol for Adults(PDF • 282.0 kb)
- Return to Learn Care Plan(PDF • 305.7 kb)
- Summary of key points(PDF • 983.0 kb)