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Find out about concussions in sport



What Are They?

Concussions are a form of mild Traumatic Brain Injury (mTBI) and according to the World Health Organization (WHO) impact more than 10 million people worldwide each year, representing 30% to 40% of all injury-related mortalities and disabilities among all age groups, with huge personal, social and economic impacts(WHO, 2006). 

The Centre for Disease Control (CDC) define mTBI as “a complex pathophysiologic process affecting the brain, induced by traumatic biomechanical forces secondary to direct or indirect forces to the head” (CDC, 2020). 

Such injury are the most common among athletes, particularly those participating in contact sports such as Gaelic football (GAA), rugby and soccer and often go undiagnosed leading to a negative impact on an athlete’s health.

What are the signs and symptoms of concussion?

The signs symptoms and effects following concussion on an individual can vary in effect and severity. Some are generally temporary and short lived, while others may last from couple of days, months and years resulting in the development of ‘post-concussion syndrome’ which is a cascade of prolonged symptoms. The signs and symptoms of a concussion are incredibly important because a concussion doesn’t show up on imaging like an x-ray, CT, or MRI scan and there is no objective test, like a blood or saliva test, that can determine if a patient has a concussion. Concussion signs and symptoms are the brain’s way of showing it is injured and not functioning normally. 

Concussion signs are observed and can range from very obvious to extremely nuance, but if only one sign is present after a hit to the head it must be reported immediately.

Concussion signs:

  • Loss of consciousness
  • Problems with balance
  • Glazed look in the eyes
  • Amnesia
  • Delayed response to questions
  • Forgetting an instruction, confusion about an assignment or position, or confusion of the game, score, or opponent
  • Inappropriate crying and/or laughter
  • Vomiting

Concussion symptoms are what someone who is concussed will tell you that they are experiencing while you observe them.

Concussion symptoms:

There are 4 main categories:

Physical Symptoms

  • Headache
  • Light-headedness
  • Dizziness – people may think they “see stars”
  • Nausea
  • Sensitivity to light and/or sound
  • Double vision
  • Postural disturbances
  • Balance problems
  • Neck pain

Cognitive Symptoms

  • Memory problems
  • Difficulties with attention
  • Loss of focus 
  • Difficulty multitasking
  • Difficulty completing mental tasks

Sleep Symptoms

  • Sleeping more than usual
  • Sleeping less than usual
  • Having trouble falling asleep

Emotional Symptoms

  • Anxiety
  • Depression
  • Panic attacks

Note: This is not a full list of concussion signs and symptoms,  they can vary in effect and severity in individuals and may take a few days to appear post TBI (critical period). These signs and symptoms are generally short lived after TBI onset, but some may become persistent and prolonged for many weeks and months developing into ‘post-concussion syndrome’.

What to do in the event of a concussion?

In the event or suspected event of a concussion the following must be adhered to immediately:

  1. The athlete should be removed from play.
  2. The athlete should not be allowed return to play the same day of the injury and should be cleared by a health professional before returning to play.
  3. The injury should be correctly diagnosed and documented.
  4. The Athletes parent/Guardian(s) should be informed of the injury acquired during play.  

How to diagnose?

Sideline detection is the initially is key, the first significant step in identifying followed by removing an athlete from play to preventing further harm. Followed by tests can be done on the sideline to identify concussion in athletes which include oculomotor tests, cognitive tests, analysis of symptoms and signs, and balance tests. There are two standard multimodal tools for the evaluation and diagnosis of concussion; Sports Concussion Assessment Tool (SCAT5) or the Concussion Recognition Tool (CRT5).

SCAT5, involves a series of different tests carried out by trained healthcare professionals, consisting of an immediate or on field assessment, followed by an off field/ office assessment. A summary of the steps involved in the SCAT5 assessment tool can be found in the table fig 1.1 below. An in-dept version of the SCAT5 tool can be found on the British of Sports Medicine site (opens a new tab).

  Immediate/on-field assessment Office or off-field assessment 
STEP 1 Look for red flags  Athlete Background assessment 
STEP 2 Are there any observable signs? Symptom Evaluation
STEP 3 Memory assessment       (Maddocks questions) Cognitive Screening 
STEP 4  Physical examination (GCS) Neurological screen
STEP 5   Delayed recall
STEP 6   Decision

Fig 1.1 


In the situation where there is no healthcare professional present, the Concussion Recognition Tool (CRT5) should be used. Which involves four steps for the identification of concussion in athletes. The first step of the CRT5 tool is to assess the athlete for red flags, these include any of the following symptoms presented below (fig 1.2): 

Neck pain/Tenderness Severe or increasing headache Deteriorating conscious state
Double vision Seizure or convulsion Vomiting
Weakness or tingling/ burning in arms or legs. Loss of consciousness Increasingly Restless, agitated or combative 

Fig 1.2


If any of the red flagged signs are observed in an individual suspected of concussion, an ambulance should be called. If none of the red flags are present identification of concussion can continue to 3 further steps, which include: 

  • Looking for observable signs
  • Assessing symptoms
  • A memory assessment 

After assessment, that athlete suspected of concussion that has already been removed from play should not be permitted to return to activity until after being assessed by a medical professional. An in-dept version of the CRT5 tool can be found at:

Current evidence of practices 

Due to the many associated health risks of concussion, its important that those involved in sports are knowledgeable on concussion and the correct practices for the diagnosis and treatment protocols’. 

A significant exists and studies have illustrated that people may be knowledgeable about concussion, however this knowledge is not necessarily translating into proper practice on every occasion. 

A study by Beidler et al in 2018 investigated knowledge, reporting and behaviors associated with concussion in club-sport athletes. They identified that participants in the study had moderate to high levels of concussion knowledge, but many may fail to report or have previously failed to report sports related concussions in the past. Participants underreported as they perceived presenting concussion signs and symptoms to not be serious enough to report. Players were unwilling to miss out on play time which was also a significant factor resulting in under reporting. Other studies have illustrated that in the sporting field the knowledge on concussions is moderate to good however the issues are seen due to misreporting and relaxed attitudes hindering the diagnosis and treatment of suspected concussion. 

This highlights that attitudes within the sporting community may be more relaxed than perceived and then they should be. Emphasis should be taken away from competitive games or possible exclusion or result as it is posing significant risk on the integrity and health and wellbeing of the athletes.

Why removal from play is important?

Recovering from concussion results in the brain cells returning to normal function by the rebalancing of brain chemical levels sodium and calcium, inside and outside of the cells. It takes a lot of energy, so rest to allow for the conserving of energy during recovery is critical. Best practise for recovery has evolved and it is recommended for a period of 24-48 hours for athlete to have cognitive and physical rest followed by a gradual return to cognitive activities and physical movement following a tightly regulated ‘return to play protocol’ once 100% symptom free (Gupta et al., 2019; McCory et al., 2018). This must however be accessed on a case by case premises by a health professional. If athlete has not recovered, they risk the potential in receiving a second impact injury which will result in worsened effects.

What is Second Impact Syndrome?

Second Impact Syndrome is a potentially catastrophic injury that occurs when an individual who has a concussion sustains a second head injury before symptoms related to the first have resolved (Headway, 2020). It occurs when concussion has and is not managed properly during the vulnerable period of TBI recovery. If SIS occurs the brain has the potential to swell in the skull space and destroy brain tissue and in some cases may lead to disability or death.

Although this is the worst-case scenario it should drive home that concussions must be taken seriously.  

This is education and action are crucial to get ahead of the game, continue competing in sports the right way and maintain the health of our athletes. 

All References Used:

Aldag, M., Armstrong, R.C., Bandak, F., Bellgowan, P.S., Bentley, T., Biggerstaff, S., Caravelli, K., Cmarik, J., Crowder, A., DeGraba, T.J. and Dittmer, T.A. (2017). ‘The biological basis of chronic traumatic encephalopathy following blast injury: a literature review’, Journal of neurotrauma [Online], Vol. 34 (1), pp. S-26-43. Available at: [Accessed 08 July 2020]

Beidler, E., Bretzin, A.C., Hanock, C. and Covassin, T. (2018). ‘Sport-related concussion: knowledge and reporting behaviours among collegiate club-sport athletes’. Journal of athletic training [Online], Vol. 53 (9), pp. 866-872. Avaiable at: [Accessed 08 July 2020]

Centers for Disease Control and Prevention, National Centre for Injury Prevention and Control (CDC). 2019. ‘What is a concussion?. [Online]. Available at:,move%20rapidly%20back%20and%20forth. [Accessed 08 July 2020]

Collins, M and Kontos, A. (2019) University of Pittsburgh Schools of the Health Sciences. UPMC ‘Science of Concussion Fall 2016’ [Online lecture & PDF]. Avaiable at: [Accessed 08 July 2020]

Graham, R., Rivara, F.P., Ford, M.A., Spicer, C.M. (2014). Sports-Related Concussions in Youth: Improving the Science, Changing the Culture. Washington (DC): National Academies Press (US). Pp. 182. Available from: [Accessed 23 January 2020]. 

Gupta, A., Summerville, G., and Senter, C. (2019). ‘Treatment of Acute Sports-Related Concussion’. Current reviews in musculoskeletal medicine [Online], Vol. 12 (2), pp. 117–123. Available at: [Accessed 08 July 2020]

McCrory, P., Meeuwisse, W.H., Dvorak, J., Aubry, M., Bailes, J., Broglio, S., Cantu, R.C., Cassidy, D., Echemendia, R.J., Castellani, R.J., Davis, G.A., Ellenbogen, R., Emery, C., Engebretsen, L., Feddermann-Demont, N., Giza, C.C., Guskiewicz, K.M., Herring, S., Iverson, G.L…Vos, P.E. (2017). ‘Consensus statement on concussion in sport: the 5th international conference on concussion in sport held in Berlin, October 2016’. British Journal of Sports Medicine [Online], Vol. 51, pp. 838-847. Avaiable at:  [Accessed 01 July 2020]

Patricios, J., Fuller, G.W., Ellenbogen, R., Herring, S., Kutcher, J.S., Loosemore, M., Makdissi, M., McCrea, M., Putukian, M. and Schneider, K.J., 2017. ‘What are the critical elements of sideline screening that can be used to establish the diagnosis of concussion? A systematic review’, Br J Sports Med [Online], Vol. 51 (11), pp.888-894. Avaiable at: [Accessed 14 July 2020]

UPMC Sports Medicine. (2020). ‘Concussion facts and statistics’, [Online]. Available at: [Accessed 23 January 2020].

West, T.A. and Marion, D.W. (2014). ‘Current recommendations for the diagnosis and treatment of concussion in sport: a comparison of three new guidelines’, Journal of neurotrauma [Online], Vol. 31 (2), pp.159-168. Available at: [Accessed: 07 July 2020]

World Health Organization (WHO). (2006). Neurological Disorders: Public Health Challenges [Online]. Available at: [Accessed: 07 July 2020]