A concussion is a syndrome characterized by an immediate and temporary alteration in the function of the brain,
including an altered state of mental status and level of consciousness, due to a
mechanical force or trauma from an injury or accident. In other words, a concussion is distinguished as an
injury to the brain caused by a blow to the head, such as an uppercut in
boxing, a clash of heads in football or a cyclist going over the handlebars
onto the ground, which may often lead to temporary loss of normal brain function involving alterations in memory, judgment, reflexes, speech, balance and muscle
coordination.
An uncommon cause of concussion involves an indirect blow where the
force of the impact is spread up to the head from another area of the body, for
instance, when a stationary rugby player is tackled from behind where the head
is suddenly flicked back, some of the force of the tackle may pass through the
brain, causing the player to suffer a concussion without receiving a direct
blow to the head.
In a majority of cases, although cuts and bruises may be present on the affected
individual’s head and/or face from the blow, many people whom experienced a
concussion never lose consciousness. Because of this, coaches and sports
physicians without the proper experience may not immediately suspect the
presence of a concussion or they often assume these are not a cause for
concern. Although the severity can vary, there is no such thing as a minor
concussion. In fact, while a single concussion shouldn’t cause permanent
damage, others could lead to permanent impairment or worse complications.
Prior studies support the concept best known as post-concussive
vulnerability, which demonstrates how another blow to the head where the brain
has already recovered from previous injury can cause worsening metabolic
alterations within the cells. This indicates the importance of properly
identifying a concussion as soon as possible to remove an injured athlete from
the field of play and ensure another concussion doesn’t occur.
Initial Concussion Diagnosis
When an
athlete suffers a blow to the head, the first priority should be to have a
qualified healthcare professional evaluate whether concussion has occurred.
While these type of assessments should always be performed by a physician specifically
trained in this area, according to the American Medical Society for Sports
Medicine, or AMSSM, the ability to perform this assessment should not purely be
determined by specialty but it should also be dictated by the specialist’s
training and experience. In other words, with proper training and experience,
coaches, trainers and healthcare professionals are more than capable of performing
a concussion assessment.
The American Medical Society for Sports Medicine also specifies that the
diagnosis of concussion must be properly achieved by a healthcare professional
who is both knowledgeable in the recognition and evaluation of concussion and
familiar with the individual involved. Standardized sideline tests are a useful
framework for making assessments, however, the validity and reliability of
these evaluations can be tremendously reduced without some form of individual
baseline test result with which to compare and any baseline score varies
according to the involved individual athlete.
Risks of Concussion
Concussions are common types of injuries in many sports and strenuous
physical activities. It is estimated that as many as 3.8 concussions occur in
the United States each year during competitive sports and recreational
activities, although, as many as 50 percent of these often aren’t diagnosed. As
a matter of fact, among individuals ranging from ages 15 to 24, sports are
second only to automobile accidents as the leading cause of head injury. According
to the Centers for Disease Control and Prevention, approximately 2 million
Americans per year experience traumatic head injuries, with 14.3 percent caused
by traffic collisions. This number may also be higher since concussions aren’t
always immediately detected after an auto accident. Research indicates that
even low-speed auto accidents can result in mild head trauma. Even those
individuals involved in a fender bender type of accident where whiplash may
have occurred, could result in head injury. Mild traumatic brain injuries or
concussions are recognized as a source of long-term complications. In addition,
traumatic head injuries occur in all sports with the highest number of
incidents occurring in football, hockey, rugby, soccer and basketball.
During a study researching the epidemiology of concussions in high
school athletes compared results between 20 different sports. Throughout the
time of the study, 1,936 head injuries were recorded concurrently with
7,780,064 athlete exposures. The percentage of injury was reported to be
greater in competition than in practice and the majority of head injuries
resulted from participation in football, about 47.1 percent, followed by girls’
soccer, about 8.2 percent, boys’ wrestling, about 5.8 percent, and girls’
basketball, about 5.5 percent. When comparing the overall results, girls displayed
higher incidents of head injury than boys while the most frequent mechanisms of
injury included player-player contact, about 70.3 percent, and player-playing
surface contact, about 17.2 percent. In more than 40 percent of the athletes
evaluated, symptoms improved within 3 days where a majority of athletes returned
to play in approximately 1 to 3 weeks.
A history of concussion can be associated with an increased chance of
suffering another injury to the head in which a greater number, severity and
duration of symptoms can express the outcome of an extended recovery. Younger
athletes are believed to experience prolonged recoveries as they can also be
more susceptible to head injuries accompanied by more serious complications. Physicians
and healthcare professionals have also stated that pre-injury mood disorders,
learning disorders, attention-deficit disorders and migraines could make an
initial diagnosis for head injury difficult.
Early prevention may be achieved through an appropriate modification and
enforcement of the rules and fair play. Helmets should also be enforced as
these can help prevent impact injuries, although further research is necessary
to determine their effectiveness to reduce the incidence and severity of head
injuries. There is no current evidence that mouth guards could reduce the
severity of or prevent concussions. Further prevention strategies may be
achieved through appropriate return-to-play management techniques and
procedures.
Concussions Explained
AMSSM Guidelines
In 2013, the AMSSM, or the American Medical Society for Sports Medicine,
announced a position statement regarding the most appropriate practice on the
initial evaluation and subsequent management of concussion in the sporting
field. The main recommendations were organized by reviewing the evidence over
several years, summarizing them as follows:
Any athlete suspected of having a concussion should be impeded from
playing in order to receive a proper assessment by a qualified healthcare
professional specializing in the evaluation and management of head injuries,
preferably, someone who is familiar with the athlete as stated above. The initial
evaluation guideline must include a symptoms checklist, a cognitive analysis
including orientation, past and immediate memory, new learning and
concentration tests and balance examinations as well as neurological and
physical assessments.
Those evaluating an athlete with a traumatic head injury should be aware
that while issues maintaining proper balance is a specific indicator of a concussion,
these aren’t necessarily true. Performing balance examinations may yield
considerably different results than baseline tests simply because of variations
in shoe/cleat-type or surface, use of ankle tape or braces, or the presence of
other lower extremity injuries which might have also occurred during the
incident involving the head injury.
Furthermore, any athlete suspected of or diagnosed with a concussion
should be closely monitored to make sure they don’t experience deterioration of
their physical or mental condition. Most importantly, the athlete should not
return to play on the same day they are diagnosed with a traumatic head injury.
In the meantime, imaging should be reserved for athletes where intracerebral
bleeding is suspected.
Even though most concussions can be properly managed without utilizing
neuropsychological, or NP, testing, the purpose of these are to measure the
condition of the brain and detect subtle cognitive impairment, as compared to simple
clinical examinations. Additionally, comprehensive NP evaluations are useful
when managing the condition of athletes after suffering a concussion with
persistent symptoms or complicated progressions. Nonetheless,
neuropsychological testing should be used only as part of a comprehensive
concussion management strategy and should not be used alone otherwise. Also,
the ideal timing, frequency and type of NP testing required for each individual
athlete’s case have not been fully determined through sufficient research and
studies.
Computerized NP tests should be analyzed by healthcare professionals who
are trained and familiar with the type of assessment and the individual test
limitations. Paper and pencil NP tests are equally as valuable and are able to
test different areas of expertise as well as assess for other conditions, which
may disguise or complicate concussion evaluations.
Before returning to play, the athlete must have improved symptoms and
they must have medical clearance from a qualified healthcare professional
trained in the evaluation and management of concussions. The proper
return-to-play progression involves a gradual, step-by-step increase in the
athlete’s physical requirements, sports specific activities and the risk of
contact. If any symptoms persist with activity, the progression should be
stopped and restarted at the previous symptom-free step. The primary concern
with early return-to-play involves the decreased reaction time leading to an
increased risk of experiencing another concussion or other type of injury which
may prolong the symptoms. Furthermore, there is an increasing concern that exposure
to impacts on the head and frequent concussions can contribute to long-term
neurological complications. Some studies have suggested concussions may be
associated with chronic cognitive dysfunction.
Healthcare professionals should be prepared to provide counseling regarding potential long-term consequences of head injury and recurrent
concussions. However, there are currently no evidence-based guidelines suggesting
an athlete should no longer participate in their specific sport after a
concussion. More generally, further efforts are required to educate athletes,
parents, coaches, officials, school administrators and healthcare professionals
alike to improve the recognition, management and prevention of concussions.
On-Field and Same Day Assessment
The initial evaluation of concussion in adult athletes can be
challenging if the symptoms indicating a head injury are not recognized,
primarily due to the evolving nature of concussive injuries. A review paper
examined the evidence related to on-field concussion assessments and studied
several questions relating to same day return-to-play including: what to do
when no physician is available on-site as well as the benefit of remote
notification of potential concussive events. It concluded that the on-field
assessment of concussions relating to sports can be difficult to diagnose,
given the elusiveness and variability of presentation, the pressure to make an
immediate diagnosis, the specificity and sensitivity of the on-field assessment
tools and the reliance on symptoms presentation.
The authors of the research concluded that on-field assessments were
based upon recognizing the presence of an injury, evaluating the symptoms,
cognitive and cranial nerve function in which balance has value. They warned,
however, that a number of assessments over a short period of time is often
required where the symptoms may have been delayed. Therefore, keeping an
athlete out of participation when there’s the suspicion of an injury is
essential. In addition, the researchers determined that although a standardized
assessment of concussion can be useful when evaluating an athlete for injury,
it should not be replaced with the judgement of a healthcare professional or another
qualified specialist.
In another study, researchers concluded that
several valid assessments can be appropriately utilized to determine the
presence of an acute concussion in competitive sporting environments, providing
essential data on the symptoms and functional disability which could be
included into a clinician’s diagnostic formulation. They also warned that such
tests should not be used alone to diagnose a concussion.
Sport Concussion Assessment Tool Variations
As previously mentioned above, the initial assessment of an athlete with
a concussion is still primarily mandatory to determine the following action a
healthcare professional must take to help treat an individual’s head injuries.
There are various diagnostic tools available, the most notable being the Sport
Concussion Assessment Tool, or SCAT. The SCAT3 is a standardized tool utilized
for evaluating concussion in athletes and it was designed for use by medical
specialists. SCAT3 took the place of the original SCAT and SCAT2. Most
importantly, baseline testing with the SCAT3 can help interpret post-injury test
scores at a later date. In the case there is no one present with medical
training to tend to an injured athlete, it is recommended to utilize the Sport
Concussion Recognition Tool instead.
Utilizing
the Sport Concussion Recognition Tool, concussion should be suspected if one or
more of the following visible clues, signs and symptoms, or errors in memory
questions are present. Visible clues include: loss of consciousness or
responsiveness; lying motionless on the ground; slow when standing; unsteady
stance; balance issues or falling over actions; poor coordination; grabbing/clutching
of the head; dazed, blank or vacant look; and confusion or unawareness of
players or events. The signs and symptoms include: loss of consciousness;
headache; seizure or convulsion; dizziness; balance issues; confusion; nausea
or vomiting; slowed down sensation; drowsiness; head pressure; feeling more
emotional; blurred vision; irritability; sensitivity to light; sadness;
amnesia; fatigue or low energy; foggy feeling; nervous or anxious; neck pain;
sensitivity to noise; difficulty remembering things, difficulty concentrating;
and an overall not feeling right sensation. Furthermore, alterations to the athlete’s
original memory function by failing to answer the following questions correctly
may suggest a concussion: what venue are we at today; which half is it now; who
scored last in this game; what team did you play last week/game; and did your
team win the last game.
If an
athlete is suspected to have suffered a head injury, they should be removed
from play immediately and should be assessed by a healthcare professional as
soon as possible. Red flags signaling a traumatic head injury requiring
immediate medical action includes: neck pain; deteriorating conscious state;
increasing confusion or irritability; severe or increasing headache; repeated
vomiting; unusual behavior change; seizure or confusion; double vision; and/or weakness
along with tingling, burning sensations in the arms or legs.
The SCAT3 is
a detailed tool that assesses the following fields: background, symptom
evaluation, cognitive and physical function, neck injury, balance and
coordination. According to the SCAT guidelines, the first results of an
assessment are essential and any of the following authorize the utilization of
emergency procedures and urgent transportation to the nearest hospital: a
Glasgow Coma score of less than 15; deteriorating mental status; potential
spinal injury; and progressive, worsening symptoms; or new neurological signs.
It’s important to give first concern to the fact that scoring using the SCAT3
should not be utilized as the sole method to diagnose a concussion, measure
recovery or make decisions about an athlete’s capacity to return to competition
after experiencing an injury. Furthermore, because the symptoms may change over time, it’s essential to consider multiple assessments when evaluating for head injuries.
Finally, when diagnosing a concussion it needs to be priority for it to be ideally identified by a healthcare professional through clinical judgement. The SCAT3
should therefore not be used only to make or exclude the diagnosis of a
traumatic head injury or concussion without seeking the appropriate evaluation
of a qualified specialist. An athlete may have experienced a concussion even if
the SCAT3 score appeared normal.
By Dr. Alex Jimenez