Concussions, otherwise known as Mild Traumatic Brain Injuries, is the most common type of Traumatic Brain Injury. Diagnosing athletes, children, car accident victims, etc., has generally improved over the years. However, Physicians still vary in diagnostic methods, as well as not having methods to declaring the patient symptom free. In the present day, most athletes must pass a baseline test to be permitted to resume all activities. In spite of this protocol, some athletes experience symptoms once they return to action, even after passing the test and being medically cleared. Concussions occur when the brain moves and impacts against the skull, due to a sudden impact. This movement is called a coup, and is followed by a countercoup, which occurs when the brain ricochets with the back end of the skull. Although concussions have been prevalent in sports for many years, the growing number of head injuries in contact sports, from the grassroots level to the professional level, has become one of the most talked about issues.
Contents1 Causes
2 Common Symptoms
3 Long Term Effects
4 Diagnostic Methods
4.1 Mild Concussion4.2 Moderate Concussion4.3 Severe Concussion4.4 Glasgow Coma Scale5 Diagnostic Imaging
6 Declaring Patient Symptom Free
7 Reasons for the Increase in Occurrences
8 Susceptibility
9 Treatment


A traumatic brain injury occurs when contact or a sudden motion causes the head to come to an abrupt stop, and causing the brain to impact against the skull. This movement is called a coup, and is followed by a countercoup, which occurs when the brain ricochets with the back end of the skull. These coup-countercoup injuries can involve focal injuries (precise point of impact), or diffuse injuries (injury to a larger portion of the brain).


The symptoms related to concussions vary greatly depending on the patient. In general, concussion patients show some sort of combination of the following symptoms: fatigue, dizziness, blurred vision, headaches, vomiting, nausea, difficulty with organization, ringing in ears, feeling sad, irritated, bothered by sounds, and confusion, along with changes in sleep patterns and sexual behaviour.


The majority of patients or athletes who suffer concussions will not have long-term effects. Anxiety, depression, irritability are the most common issues patients complain of. In addition, difficulty with balance, attentiveness, movement, reaction time, and concentration, are also all prevalent for athletes who have suffered multiple concussions throughout their careers. Athletes with a history of three concussions or more display significantly attenuated SPCN (sustained posterior contralateral negativity) amplitude, greatly affecting their working memories years after their careers are over. In addition, athletes who had a previous history of at least one concussion, were nine times more likely to have greater anterograde and retrograde amnesia following a concussion than those without such a history.


Concussions can be organized in a few different ways, including: open/closed injuries, focal injuries, or diffuse injuries. In addition, classification of the severity is also done to the patient. The severity of the injury is tested and based on the following: how long the patient lost consciousness, memory loss, and The Glasgow Coma Scale score.

Mild Concussion:
A loss of consciousness, if any, for less than 30 minutes, memory loss less than 24 hours, and a Glasgow Coma Score of 13 – 15

Moderate Concussion:
A loss of consciousness that lasts for more than 30 minutes but less than 24 hours, memory loss anywhere from 24 hours to 7 days, and a Glasgow Coma Score of 9 – 12

Severe Concussion :
A loss of consciousness that lasts for more than 24 hours, memory loss for 7 days or more, or a Glasgow Coma Score of 8 or less, which signifies that the patient is in a coma.

When the patient is conscious, a series of questions may be asked to determine their mental state. Questions such as “what is your name?”, “what is today’s date?”, and “do you know where you are?” can be asked to help determine if the patient is confused. The patient may also be asked to perform simple movements such as holding up a specific number of fingers or moving their limbs in order to determine if they can move and understand what is happening around them.

Glascow Coma Scale:
The Glasgow Coma Scale is a test to measure the severity of the injury. It examines the patients eye opening abilities, verbal responses, and motor responses are each assigned a score and then tallied together. A low score indicates a severe concussion.

Best Motor Response (M)

To verbal command: obeys
To painful stimulus: localizes pain
No response

Eye Opening (E)

To speech
To pain
No response

Best Verbal Response (V)

Oriented and converses
Disoriented and converses
Inappropriate words
Incomprehensible sounds
No response


Advancements in diagnostic imaging and their technologies have resulted in patients being diagnosed with concussions, that have in the past gone undetected. Imaging tests such as CT scans and MRIs show swelling and bleeding, however these tests on occasion may appear normal in patients with mild concussions. Concussions, particularly less severe ones, frequently involve minor physical and chemical modifications in the brain. As a result, detecting these injuries are extremely difficult, and sometimes impossible through CT scans and MRIs.

CT Scan:
Modern CT scans distinguish between gray and white matter and differentiate ventricles. Spatial resolution on the order of millimetres.
Magnetic resonance imaging, or MRI, Produces 3-D images with very high spatial resolution (able to see small structures).
Intracranial Pressure Monitoring measures intracranial pressure for patients who had suffered a severe concussion. Intracranial pressure is increased when the brain begins to swell due an injury. Some non-invasive methods are currently being studied
Electroencephalograph measures brain activity. Electrodes are applied to the skull to detect the electrical activity occurring in the brain.


Patients who are symptom free, must first consult a Physician before returning to their daily activities. Physical tests are done to attempt to simulate physical exertion. In the case when concussion symptoms reoccur after physical exertion, then the patient must be re-evaluated on a later date and continue to rest. Under no circumstances should a patient with any form of concussion/head injury, return to their full daily activities without being completely symptom free.


An important reason TBI are more prevalent is that people are able to survive injuries that would most likely have been fatal not too long ago. Improvements in equipment, such as helmets, allow for better protection of vital organs. Nevertheless, helmets unfortunately do not protect the brain from acceleration/deceleration injuries, which have the potential to cause a concussion. Advancements in medicine and diagnostic imaging have also played a key role in higher survival and incidence rates among patients with TBI. In addition, the increase is associated with a better clinical awareness of TBI. Physicians, athletes, and parents of children involved in organized sports, are now more aware of the symptoms and the short and long term effects of TBI.


Another critical discovery about concussions is that after one brain injury, the likelihood of subsequent injuries is vastly greater. Patients who have suffered three or more concussions, are three times more susceptible to further concussions, then people with no concussion history. Mild concussions are more often than not treatable and the patient usually makes a full recovery. However, if subsequent concussions occur in close proximity to each other, a cumulative effect can occur, causing the symptoms to be much more severe than the initial injury, making recovery much more difficult.

Studies have shown that the occurrence of concussions in high school athletes is higher than in older athletes. Many factors contribute to the increased susceptibility associated with young athletes, these include: the immaturity of the adolescents’ central nervous system, the lack of recognition that a concussion had occurred, and the reliance upon subjectivity associated with self-reporting of symptoms.

Not recognizing immediately that an athlete has suffered a concussion can be devastating and result in further damage, such as Second Impact Syndrome and the development of Post-Concussion Syndrome. Typically, Second Impact Syndrome occurs when the athlete suffers a second injury to the head, while not fully recovered from the initial blow, causing massive swelling. Post-Concussion Syndrome results in the athlete experiencing headaches, dizziness, irritability, and eventually depression for an extended period of time, usually more than six weeks. Due to these symptoms daily activities of the athlete are affected greatly, impacting their social life and academic performance.


In most cases, if early detection occurs, patients usually make a full recovery and can return to everyday activities. Prescribed medications are taken to reduce some symptoms associated with mild TBI. In addition, Physicians strongly recommend a patient who is suffering from a concussion to: Stay away or reduce the amount of work and activities for 1-2 weeks (depending on severity), stay from any activity that might cause a second concussion until completely symptom free, rest, have a proper diet, and keep the body moving by doing very simple, non exerting exercises.


1. Anderson MK (2003). Fundamentals of sports injury management. Hagerstown, MD: Lippincott Williams & Wilkins. pp. 79.

2. Brooks D, Hunt B (2006). "Current concepts in concussion diagnosis and management in sports: A clinical review". BC Medical Journal 48 (9): 453–459.

3. Cantu RC (2001). "Posttraumatic Retrograde and Anterograde Amnesia: Pathophysiology and Implications in Grading and Safe Return to Play". Journal of Athletic Training 36 (3): 244–8

4. Cunha, John P. "Concussion." Brain & Nervous System. EMedicinehealth, 9 June 2010. Web.

5. De Beaumont, L., Jolicoeur, P., Lassonde, M., Theriault, M., and Tremblay, S. "Cumulative effects of concussions in athletes revealed by electrophysiological abnormalities on visual working memory". Journal of Clinical and Experimental Neuropsychology. 33, 30-41 (2010).

6. Echlin, Paul S. "Sport Concussion Library." Concussions. Canadian Medical Association, 2011. Web.

7. Erlanger DM, Kutner KC, Barth JT, Barnes R (1999). "Neuropsychology of sports-related head injury: Dementia pugilistica to post concussion syndrome". The Clinical Neuropsychologist 13 (2): 193–209

8. Finnoff, Jonathan T. "Concussion." Mayo Clinic, 22 Feb. 2011. Web.

9. Guskiewicz, K. M. "Cumulative Effects Associated With Recurrent Concussion in Collegiate Football Players: The NCAA Concussion Study." JAMA: The Journal of the American Medical Association 290.19 (2003): 2549-555.

10. Hunt T, Asplund C. Concussion assessment and management. Clin Sports Med . 2009;5-17.

11. McAllister TW, Sparling MB, Flashman LA, Saykin AJ (2001). "Neuroimaging findings in mild traumatic brain injury". Journal of Clinical and Experimental Neuropsychology 23 (6): 775–91

12. Mueller, Frederick O. "Center Information." Catashtrophic Sport Injury. National Center for Catastropic Sport Injury Research, Feb. 2011. Web.

13. Mueller, Karla A. "“Heads Up”: Concussions in High School Sports." Clinical Medicine & Research 2.3 (2004): 165-71. Print.
14. Morrison AL, King TM, Korell MA, Smialek JE, Troncoso JC (1998). "Acceleration-deceleration injuries to the brain in blunt force trauma". American Journal of Forensic Medical Pathology 19 (2): 109–112

15. Ropper AH, Gorson KC. Clinical practice: concussion. New England Journal Medicine. 2007;356:166-172.

16. Webbe FM, Barth JT. Short-term and long-term outcome of athletic closed head injuries. Clin Sports Med 2003;22:577-592

17. "Injury Prevention & Control: Traumatic Brain Injury." Concussion and Mild TBI. Centers for Disease Control and Prevention, 11 Oct. 2011. Web. <>