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Concussions: Getting your head out of the game

October 3, 2014
American Medical Society for Sports Medicine
Concussions, sometimes referred to as mild traumatic brain injuries, are one of the most commonly encountered sports injuries. Studies vary but rates are estimated at two million sport related concussions per year in the United States.

Concussions, sometimes referred to as mild traumatic brain injuries, are one of the most commonly encountered sports injuries. Studies vary but rates are estimated at two million sport related concussions per year in the United States. It is also commonly believed that these are under reported injuries due to lack of recognition of the concussion and the desire of athletes to not miss time from their activity.

Research has led to change in our approach to treatment of the injuries. New guidelines do not use a set time away from activity and emphasize a gradual return to play. While concussions often occur from direct contact to the head or face, they may also occur from rotational forces without contact such as a tumbling fall. Although research continues to help understand what happens to the brain in a concussion, it appears that the neurons (brain cells) sustain a small injury that creates an "energy crisis." This generally lasts 7-10 days and physical or cognitive activity during this time period may worsen symptoms and prolong recovery. This is why rest is so important in the initial stages of treatment. Collision sports (football, hockey, etc.) generally have the highest overall rates of concussion; however, they can be seen in all sporting activity. Fortunately, the overall rates of concussions are relatively low even in collision sports. Certain risk factors are associated with an increased risk of concussion or prolonged recovery. Genetics, gender, playing position, migraines, history of multiple concussions and mental disorders (depression, anxiety and ADHD) all may play a role in how an athlete is affected by a concussive injury.

However it is still unclear how much influence each of these factors has on an individual athlete's risk. The diagnosis of a concussion can be complex as the signs and symptoms of concussions can be found in many other conditions and there is not a singular test we can use to determine if a concussion has occurred. Sometimes the diagnosis is very straight forward, for example when there has been a brief loss of consciousness, but many times the changes seen in the athlete are very subtle. The diagnosis of a concussion is mainly based on the history and physical examination. Symptoms of a concussion may include headache, dizziness, nausea/vomiting, amnesia, brief loss of consciousness and inability to concentrate. These symptoms may last for several days to a few weeks.

Imaging, CT scan or MRI, rarely indicate concussions, unless there is a finding on examination that suggests a structural injury ( e.g. bleeding or swelling). Newer computerized tests may add value in some cases, but these tests are not used to diagnose concussions and it is unclear if using these tests improve the outcomes of concussed athletes. Previous grading scales used symptoms at the time of the concussion to determine the severity of the concussion. New guidelines now suggest that we not grade concussions at all and that we only determine that a concussion has occurred. The reasoning for this lies in newer research that shows symptoms at the time of the initial injury do not correlate with the severity of the injury and recovery time. Additionally, grading does not change our treatments as resting until symptoms have resolved is the initial treatment regardless of the injury.


When an athlete is suspected of having a concussion, they should be removed immediately from competition. Symptoms should be monitored and the athlete should not be returned to competition until they are evaluated by a qualified medical professional. This evaluation should occur as soon as possible. The athlete should be monitored closely for several hours after a concussion. It is important to stress that both physical and mental rest speed the recovery of concussions. It is okay for the athlete to sleep and should avoid over stimulation such as video games or loud crowded activities. Athletes may need to stay out of school or have modified class schedules.

Ask your health care provider for more specific recommendations. Returning the athlete to play starts when the athlete is symptom free. It will take 3-7 days for full return to sports (depending on the sport) with an athlete gradually increasing their activity level every 24 hrs. Returning to class can occur over the same timeframe and athletes should be monitored as well for any increase or recurrence of symptoms. Activity can surface underlying concussion symptoms and athletes should be instructed to notify their coach, trainer or physician if they redevelop any symptoms during the recovery period. This process allows faster and safer return to sporting activity. Computerized neuropsychological testing is sometimes used to help monitor an athlete's progress but is never used on its own to determine a diagnosis or an athlete's readiness to return to play. There are many common misconceptions about concussive injuries.

The following are several myths about concussion:

Every athlete who sustains a hard hit must have a concussion. Although our knowledge about the forces involved in concussion is improving we still have not found a level of force that definitely causes a concussion. At times high forces do not cause an injury and relatively lower ones may. This means that we should not overact to every head impact but also need to listen to athletes who complain of concussive like symptoms after any head contact. Because there is no known force level for concussion in-helmet devices that are marketed to consumers as "concussion alarms," they are not recommended as they will likely lead to both over and under diagnosis of concussive injuries.

Better helmets and mouth guards will prevent concussions. Unfortunately there is no good scientific evidence that helmets of any type (hard shells, soft-padded or head bands) or mouth guards can prevent or reduce the risk of concussions. Hard helmets can reduce the risk of more serious head injuries (bleeding, skull fractures etc.) and should be worn in high risk sports. Mouth guards can prevent dental injuries and should be worn for sports with a high risk of these injuries. Helmet-add ons additionally are not effective in concussion prevention and using these will generally void any warranties associated with the helmet. Risk reduction may be possible in some settings with rule changes (e.g. no hitting from behind in hockey) and behavior changes (e.g. tackling technique in football).

Once you have a concussion you will always be more susceptible to having another one. While there appears to be an increased risk of recurrence in the first few weeks after a concussive injury it is unclear what factors may influence the risk of another injury in the future. Despite being a commonly held belief there is no evidence to suggest that athletes develop a decreasing force threshold after each injury. A few small studies have found the opposite. The largest risk to any athlete for a recurrent concussion is exposure (playing a sport) and since most athletes who have a concussion plan on continued participation this likely is the leading cause. Other risk factors discussed before may play a role but this is not yet defined. Management of concussion will continue to evolve as more research develops. Removal from competition and early intervention with a healthcare professional knowledgeable about concussions will help protect our athletes and allow the fastest and safest return to play.

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American Medical Society for Sports Medicine. "Concussions: Getting your head out of the game." ScienceDaily. ScienceDaily, 3 October 2014. <>.
American Medical Society for Sports Medicine. (2014, October 3). Concussions: Getting your head out of the game. ScienceDaily. Retrieved July 23, 2024 from
American Medical Society for Sports Medicine. "Concussions: Getting your head out of the game." ScienceDaily. (accessed July 23, 2024).

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