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CONCUSSION (Mild Traumatic Brain Injury)
By Jamie Nuwer, MD.
Illustrated by Sierra Simmons
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Download “SCAT (Sport Concussion Assessment Tool) Card”

The brain in concussion. The area that maintains consciousness in the upper brainstem is shown in red. The brainstem is fixed-in-place by the neck bones and skull, whereas the brain is free to move forward into the front of the skull as shown by the yellow arrow. The resulting twist on the pivot point of the brainstem (shown in red) causes a “daze” or full-blown loss of consciousness.
Concussion (Mild Traumatic Brain Injury) occurs more frequently than many athletes realize. Even a simple “ding” which leaves a player momentarily dazed is due to mild brain injury1. Concussions represent 3-5% of injuries in all sports, but they are under-reported and under-recognized so the actual number is probably higher1. Concussions have been a subject of vigorous debate prompting several national and international meetings to create consensus statements since 2000. This article examines recent consensus statements on concussion and will discuss the mechanism, evaluation, and management of concussions. This column is not meant to replace medical evaluation for your health problems. Always seek medical help for worrisome or persistent symptoms.

Concussions occur when the head is brought forcefully against a fixed object such as the ground or another player’s body. Inside the skull the brain moves forward at an angle, pivoting around the brainstem and slamming into the skull as shown in Figure 1 3. The neurons that maintain alertness are located at the upper brainstem pivot point and injury in that area during concussion causes a decrease in alertness (“dazed”) or loss of consciousness3. Many other mechanisms of brain injury have been proposed including biochemical and metabolic changes as well as alterations in gene expression4. This variety of changes occurring after brain injury may help explain the variety of symptoms experienced after concussions.

When a concussion occurs, the athlete should be immediately evaluated by a trainer if available. Never move an unconscious athlete because this can make neck injuries worse. If the athlete is unconscious for more than a minute, call 911 for emergency medical attention. Fortunately, most concussions in Ultimate do not require emergency medical treatment. After a concussion with no loss of consciousness or a brief loss of consciousness, the athlete should leave the game and be evaluated on the sideline.

The 2nd International Conference on Concussion in Sport created a “SCAT (Sport Concussion Assessment Tool) Card” for evaluating athletes with concussions. This extremely useful card summarizes all the important information about concussions for easy sideline evaluation and treatment. The card can be downloaded for free.

Someone, preferably a trainer, should evaluate the athlete for the symptoms listed in Tables 1 and 2. Write down their symptoms and check them again at 5 minute intervals until all symptoms have disappeared1. This information helps medical professionals determine the severity of the concussion since severity is graded by the number, type, and duration of concussion symptoms2. Pay special attention to the appearance of new symptoms or symptoms getting worse. Persistent, new, or worsening symptoms require medical attention1. Do not leave the injured athlete unsupervised until all symptoms have cleared2. If the symptoms have not cleared by bedtime, the athlete may need to be woken up at night to check for worsening of symptoms. This is especially important if they had a loss of consciousness or amnesia1.

A brief loss of consciousness (seconds) on its own does not necessarily indicate a severe concussion4. However, it is recommended that any loss of consciousness be immediately evaluated by a medical professional1. Some other indications to seek immediate medical help are listed in Table 21-2. That being said, any symptoms that the athlete, parent, or coach considers worrisome or persistent do merit prompt medical attention.

Sometimes athletes have some twitches or jerks while unconscious. This is may be frightening to witnesses. Fortunately these movements are usually harmless and do not require any treatment4. However if a more serious convulsion occurs or if the jerking does not cease rapidly, call 911 for emergency medical treatment.

What concerns most athletes is when they can go back to playing Ultimate. There is still considerable and ongoing debate about such “return-to-play” (RTP) decisions. In 2006 the American College of Sports Medicine published a consensus statement that addresses RTP decisions2. It was endorsed by twelve major American sports medicine organizations6. Their recommendations are summarized in Table 3. The decision to RTP should be individualized, and not based on a rigid timeline. Athletes with persistent or worsening symptoms should not RTP. Also, athletes that experienced a loss of consciousness or any amnesia, regardless of how quickly it resolved, should not RTP on the same day. A previous concussion increases the risk for a second concussion even with mild impact. It is always safest to sit the athlete out.

Returning to play the next day or afterwards should be guided by the principles summarized in Table 32. First, the athlete must have no residual symptoms at rest. The athlete should then undergo progressively more taxing exercises, then non-contact drills, then full playing. If the athlete experiences any symptoms during a task, they should stop and wait 24 hours before trying the task again. It is important to work up progressively to make sure the athlete is symptom free before RTP. The athlete should understand the increased risk of concussion after a prior concussion and sensibly avoid situations that lead to concussion.

Another method of evaluating RTP decisions is formal cognitive testing. Formal cognitive written or computerized tests can help identify subtle changes and aid in RTP decisions5. These tests are far more useful when taken before the concussion so that results can be compared after a concussion5. “Cognitive rest” while symptomatic from a concussion is recommended, particularly for athletes 18 and under, because intense scholastic activities may prolong and exacerbate concussion symptoms4.

Second-impact syndrome, a very rare complication of concussions, can occur when an athlete is not fully recovered and receives a second concussion. The second concussion causes the brain to swell catastrophically which most often leads to death1. Almost all reported cases have been in young athletes age 18 and under1. From 1992-1999 there were only 17 reported cases6. Given this rare yet very serious risk, young athletes should be managed with stricter RTP guidelines.

Post-concussion syndrome occurs when concussion symptoms persist for weeks to months. The athlete should not RTP while still symptomatic. Further evaluation by a specialist is often warranted in this situation.

It is important to recognize and appropriately treat concussions in order to avoid prolonged symptoms and cumulative brain injury before the brain is fully healed. There is still considerable and ongoing debate about concussion and return-to-play decisions, but the bottom line is clear, “When in doubt, sit them out” 4.

REFERENCES
1. Guskiewicz KM, Bruce SL, Cantu RC, Ferrara MS, Kelly JP, McCrea M, Putukian M, McLeod TC; National Athletic Trainers' Association. Research based recommendations on management of sport related concussion: summary of the National Athletic Trainers' Association position statement. Br J Sports Med 2006 Jan;40(1):6-10

2. Herring SA, Bergfeld JA, Boland A, Boyajian-O’Neill LA, Cantu RC, Hershman E, et al. Concussion (mild traumatic brain injury) and the team physician: a consensus statement. Med Sci Sports Exerc 2006;38:395-398

3. Ropper AH and Gorson KC. Clinical practice: Concussion. N Engl J Med 2007 Jan 11;356(2):166-72.

4. McCrory P, Johnston K, Meeuwisse W, Aubry M, Cantu R, Dvorak J, Graf-Baumann T, Kelly J, Lovell M, Schamasch P. Summary and agreement statement of the 2nd International Conference on Concussion in Sport, Prague 2004. Br J Sports Med 2005 Apr;39(4):196-204.

5. Cantu RC, Aubry M, Dvorak J, Graf-Baumann T, Johnston K, Kelly J, Lovell M, McCrory P, Meeuwisse W, Schamasch P, Kevin M, Bruce SL, Ferrara MS, Kelly JP, McCrea M, Putukian M, McLeod TC. Overview of concussion consensus statements since 2000. Neurosurg Focus 2006 Oct 15;21(4):E3.

6. Harmon KG. Assessment and management of concussion in sports. American Family Physician 1999 Sept 1;60(3):887-894

Special thanks to Marc Nuwer MD PhD, Abby Goodhue, and Daniel “Bones” Brady for their editing comments.


Table 1: Symptoms of concussion reported by the athlete
Cognitive Sensory Emotional
Loss of consciousness Fatigue Irritability
Seeing stars Headache Nervousness
Vacant stare/glassy eyed Nausea/Vomiting Sadness
Feeling “slowed down” Dizziness Quickly shifting emotions
Feeling “in a fog” Poor balance/coordination More intense emotions
Disorientation Ringing in the ears Personality change
Memory problems Sensitivity to noise  
Easily distracted Sensitivity to light  
Sleep disturbance Blurred vision  
Excess sleep    

Table 2: Reasons to seek medical attention. Additional signs not listed here may be checked by a trainer or medical professional.
Call 911 for emergency medical help See a doctor as soon as possible
Convulsion more than a few twitches Any loss of consciousness
Loss of consciousness longer than 1 minute Amnesia for more than 15 minutes
Decrease in level of consciousness Vomiting
Difficulty awakening Mild symptoms that persist
Increased confusion or agitation Emotional symptoms that persist
Increased difficulty with balancing Sleep disturbances that persist
Any weakness, numbness, or tingling Cognitive difficulties that persist
Decreased or irregular pulse  
Decreased or irregular breathing  
Unequal, large, or unchanging pupils  

Table 3: Making a decision to Return to Play (RTP)
Reasons to absolutely refuse same-day RTP May not RTP until… Delay RTP longer if…
Any persistent or worsening symptoms No symptoms at rest Athlete is age 18 or under
Any loss of consciousness No symptoms with gradually increased exertion Concussion is severe
Any amnesia Athlete understands the increased risk of concussion after an initial concussion Concussion occurred with a relatively minor blow
    Second or multiple concussions



DISCLAIMER: The information contained on this website is not meant to be a substitute for evaluation by a qualified health care professional. The information provided here is meant for educational and informational purposes only. It should in no way be considered as formal medical advice for your health problems. You should consult a qualified health professional if you are seeking medical advice for an injury or illness. Go to the emergency room or call 911 for any severe injury or illness.