3. iv
ACKNOWLEDGMENTS
I would like to thank my adviser and chairperson of my committee, Dr. Pamela
Hansen, for her time, effort, encouragement, and dedication she has provided throughout
this literature review and furthermore my degree. I have nothing but sincere appreciation
towards my graduate degree committee members, Dr. Donna Terbizan, Dr. Linda
Manikowske, and Kara Gange, for all their time and suggestions they offered to complete
my literature review. Finally, I would like to thank my instructors, my family, and my
peers for all their support throughout my graduate school experience at NDSU.
6. 1
CHAPTER 1
INTRODUCTION
A concussion is a disturbance in brain function occurring from rapid acceleration or
deceleration forces as a result of violent shaking of the head. Common signs and symptoms
of a concussion include dizziness, confusion, amnesia, or loss of consciousness (Anderson,
Hall, & Martin, 2004). An athlete who receives a direct blow to the head or body contact
causing forceful movement of the neck must be carefully evaluated for a possible brain
injury (Prentice, 2006).
According to Covassin, Swanik, and Sachs (2003), interest in concussion signs and
symptoms, evaluation, and long-term consequences has increased in recent years.
Concussions are more common in some collegiate sports than previously noted. Notebaert
and Guskiewicz (2005) reported that no simple tests can be performed on the brain to
determine the severity of a closed head injury and to help clinicians establish goals for
return-to-play. Litt (1994) reported a 16-year-old football player who developed a
headache following a collision during a game. When his headache persisted for one week,
he underwent a computerized tomographic (CT) scan to determine the cause. The findings
were normal, and the athlete was diagnosed with a concussion. Seventeen days post-injury,
the athlete reported to be asymptomatic at rest and with exertion. The athlete continued to
deny symptoms and was cleared for unlimited participation 30 days post-injury. In the next
game, the athlete collided with an opposing player, ran to the sidelines, and deteriorated on
the sidelines after complaining of dizziness. The athlete was transported to the local
medical facility, and neurosurgeons diagnosed a right subdural hematoma by CT scan. In
an interview four months post-operatively, the athlete admitted having experienced
8. 3
performance with his or her own pretrauma baseline performance (Erlanger, Saliba, Barth,
Almquist, Webright, & Freeman, 2001).
Standardized Assessment of Concussion (SAC): An abbreviated neuropsychological test
designed to provide medical personnel and athletic trainers responsible for clinical decision
making in the care of athletes with immediate objective data concerning the presence and
severity of neurocognitive impairment associated with a concussion (Prentice, 2006).
Balance Error Scoring System (BESS): A sideline measure of balance that uses double-
leg, single-leg, and tandem stances on both firm and foam surfaces (Patel, Mihalik,
Notebaert, Guskiewicz, & Prentice, 2007).
Computed Tomography (CT): A form of radiography that provides cross-section of
tissue that is 100 times more sensitive than radiographs. It is effective in detecting stress
fractures, tumors, bleeding, and soft tissue abnormalities (Cuppet & Walsh, 2005).
Post-Concussion Syndrome: Delayed condition characterized by persistent headaches,
blurred vision, irritability, and inability to concentrate (Anderson et al., 2004).
Cantu Grading Scale: A concussion grading scale that uses the duration of loss of
consciousness and post-traumatic amnesia to differentiate mild, moderate, and severe
concussive injury (Anderson et al., 2004).
Neurocognitive Testing: A helpful piece of additional information to assist in diagnosing
and managing concussions in order to provide the greatest amount of objective clinical
information during the post-concussion evaluation (Van Kampen, Lovell, Pardini, Collins,
& Fu, 2006).
Neuropsychological Testing: The administration of various tests of cognitive abilities
(e.g. memory, attention, language, visuospatial skills, etc), tests of psychological
10. 5
Organization of Paper
Chapter 1 discusses the Purpose Statement, Definitions, Project Significance,
Specific Objectives, and how the review was conducted. Chapter 2 reviews the literature
on the various neuropsychological and neurocognitive tests, and return-to-play guidelines.
Chapter 3 includes the Discussion of concussions and the evaluation tests.
12. 7
include feeling stunned or seeing bright lights, brief loss of consciousness, loss of balance,
headaches, personality changes, and cognitive and memory dysfunction. These authors are
in agreement that typical symptoms of a concussion include dizziness, confusion, loss of
consciousness, and amnesia. This literature review used the signs and symptoms described
by Anderson et al. (2004).
Assessing a concussion requires the athletic trainer to complete a thorough
evaluation. Onate, Guskiewicz, Riemann, and Prentice (2000) reported that objective
sideline assessment of a mild head injury includes the use of symptom checklists, cognitive
tests, and postural control tests. Various methods of postural stability analyses have been
proposed for assessing mild head injury, yet few of these tests can be used for immediate
sideline assessment. The typical sideline evaluation consists of assessing orientation to
time, place, person, situation, and simple memory and concentration tests. Establishing
normative cognitive baseline allows the practitioner to make a more objective decision so
that an athlete can safely return to competition. Onate, Beck, and Van Lunen (2007)
assessed whether testing environment affects Balance Error Scoring System (BESS) scores
in healthy collegiate baseball players. The BESS is a system developed as a standardized,
objective assessment tool for the clinical sideline assessment of postural control. The
BESS uses three stances, including double-leg, single-leg, and tandem, on both firm and
foam surfaces. Onate et al. (2007) found that BESS performance was impaired when
participants were tested in a sideline environment compared with a clinical environment.
Consistent environment settings should be used for both baseline and follow-up testing
after concussion. Onate et al. (2007) recommend future researchers to focus on various
sporting environments in practices and games, testing in different environmental
13. 8
conditions, such as hot or cold temperatures; and the effect of ankle taping, and ankle or
knee bracing on BESS scores.
Certified athletic trainers also need to be aware of the exertion effects when
administering the BESS after physical activity. According to Susco, Valovich McLeod,
Gansneder, and Schultz (2004), a significant decrease in BESS performance with exertion
was found. Exertion had the greatest effects on the tandem and single-leg stance conditions
at 0, 5, 10, and 15 minutes following activity. Administering the BESS immediately after a
concussive injury could cause false-positive findings. Therefore, Susco et al. (2004)
reported that waiting 15 to 20 minutes before performing the BESS following injury would
decrease the exertion factor and enhance the accuracy of the post-concussive results.
Wilkins, Valovich McLeod, Perrin, and Gansneder (2004) also found exertion to affect the
BESS. Significant increases in total errors were found when the athletes were fatigued
when administering the BESS. Thus, clinicians who use the BESS as part of their sideline
assessment for concussion should not administer the test immediately after a concussion
due to the effects of fatigue.
Meanwhile, Valovich, Perrin, and Gansneder (2003) found a significant practice
effect on the BESS during the course of repeated administration. After repeatedly testing
32 uninjured subjects on the BESS, the number of BESS errors decreased with each test
session, especially with the single-leg stance on a foam surface. Errors scored on day five
and seven were significantly lower than the baseline score. Therefore, Valovich et al.
recommended that clinicians consider practice effects on the BESS when readministering
concussion evaluations to track recovery of an athlete or to determine whether an athlete is
ready to return-to-play.
14. 9
In certain situations, secondary signs and symptoms of a concussion may arise.
This is known as post-concussion syndrome. Anderson et al. (2004) stated that post-
concussion syndrome occurs more frequently in women than men. Cognitive impairments
may vary from 48 hours post-trauma, lasting to several weeks or months following the
concussion. Typical symptoms of the syndrome include decreased attention span,
persistent headaches, blurred vision, vertigo, or irritability.
If an athlete returns to play prior to being asymptomatic, the athlete may be
predisposed to further injury, resulting in second impact syndrome. Anderson et al. (2004)
reported that second impact syndrome occurs when an individual who has sustained a head
injury, usually a concussion, sustains another head injury before the individual is entirely
asymptomatic. The individual may appear stunned, but often finishes the play, and usually
walks off the field under their own power. Intracranial pressure is increased as a result of
vascular engorgement, the brain stem becomes compromised, and the individual may
collapse with rapidly dilating pupils, loss of eye movement, coma, and respiratory failure
(Anderson et al., 2004).
According to Anderson et al. (2004), once a concussion has been diagnosed, the
concussion is categorized into various grades in order to determine the severity of the head
injury. There are over 16 different classification schemes that define the various degrees of
a concussion. Anderson et al. reported four grading scales: Cantu; Torg; Colorado Medical
Society; and American Academy of Neurology. Anderson et al. (2004) stated that Robert
C. Cantu developed a concussion classification that many sports medicine clinicians have
adopted. The Cantu grading scale uses the duration of loss of consciousness and post-
traumatic amnesia to differentiate mild, moderate, and severe concussions. Dr. Joseph Torg
15. 10
developed another classification system that includes six separate grades of concussion,
including facial expression, determining orientation of time, place, and person, testing for
any post-traumatic and retrograde amnesia, and gait evaluation. The Colorado Medical
Society is a concussion grading scale that was developed after a single head injury death
from second impact syndrome in a high school athlete in Colorado. This athlete served as a
means for Dr. James Kelly and the Colorado Medical Society to study head injuries and
their management. The guidelines created stricter requirements for assessing the severity of
concussions and required emergency transport to the hospital for all individuals that
experienced unconsciousness for any length of time. The American Academy of
Neurology created a modification to the Colorado Medical Society that included nine
features of concussions frequently observed, and early and late symptoms of concussions
(Anderson et al., 2004). Cantu (2001) stated that concussion grading guidelines all focus
on loss of consciousness and post-traumatic amnesia as key signs in the grading schemes.
(See Table 1.)
Table 1. Grading Scales for Athletic Head Injury (Anderson et al., 2004)
Grade I/Mild Grade II/Moderate Grade III/Severe
Cantu No LOC or PTA <1 hour LOC < 5 minutes LOC >5 minutes
PTA 1-24 hours PTA >24 hours
Torg Grade I-II Grade III-IV Grade V-VI
No LOC or amnesia LOC < few minutes LOC/coma, confusion,
(except PTA) PTA or retrograde amnesia amnesia
CMS No LOC, confusion, No LOC, confusion, with amnesia LOC
no amnesia
AAN No LOC No LOC Any LOC
Sxs <15 minutes Sxs >15 minutes
AAN= American Academy of Neurology; CMS= Colorado Medical Society;
Cantu= Dr. Robert Cantu; Torg= Dr. Joseph S. Torg; LOC= Loss of consciousness;
PTA= post-traumatic amnesia; and Sxs= symptoms (i.e., confusion, amnesia, etc.).
16. 11
The National Athletic Trainers’ Association position statement on management of
sport related concussions states that the two most recognizable signs of a concussion are
loss of consciousness and amnesia (Guskiewicz, Bruce, Cantu, Ferrara, Kelly, McCrea, et
al., 2004). But Guskiewicz, et al. (2004) noted that neither is required for an injury to be
classified as a concussion. Most grading scales rely on loss of consciousness and amnesia
as primary factors for predicting the severity of a concussion. However, recent research
suggests that these two factors are not good predictors of the severity of a concussion.
Guskiewicz et al. reported that there is no association between loss of consciousness and
duration of symptoms, or loss of consciousness and neuropsychological and balance tests
at three, 24, 48, 72, and 96 hours post injury. Amnesia, however, appears to be less clear.
Guskiewicz et al. stated that amnesia was recently found to predict symptom and
neurocognitive deficits at two days post injury. Yet, additional research is warranted to
help improve clinical decision making.
Concussions are more prevalent in collision sports like football, rugby, and soccer.
In a research study by Marshall and Spencer (2001), it was found that concussions are a
major concern in rugby. Participants are unshielded from collision forces and the cranium
is subjected to violent acceleration or deceleration forces and rotational forces. Any player
who self-reports or is diagnosed as having a concussion is subject to an automatic three-
week suspension, so many concussions go unreported. Two rugby teams were followed for
three years. Seventeen concussions were recorded and accounted for about 25% of all
reported injuries. Concussions were graded on the Cantu grading scale. Marshall and
Spencer reported 14 concussions as grade one, two were grade two, and one was grade
three. The rate for all injuries overall was 1.5 per 1000 athlete-exposures. The concussion
17. 12
rate was 11.3 per 100. Concussions accounted for 25% of all days lost from rugby
participation due to injury. Due to the limited medical personnel and administrative rules
that suspend athletes from playing, the incidence of concussions go unreported, and efforts
to prevent, recognize, and manage these injuries need to be implemented (Marshall &
Spencer, 2001).
Macciocchi, Barth, Littlefield, and Cantu (2001) analyzed neurocognitive and
neurobehavioral consequences of an athlete sustaining one concussion and an athlete with
two or more concussions in collegiate football players. The primary goal was to determine
if a second concussion produced identifiable cognitive deficits above and beyond those
observed after a single injury. All players were assessed preseason to establish baseline
functioning. Players completed several neuropsychological measures to assess various
aspects of visual and auditory attention, as well as information processing speed. No
statistically significant difference in test performance was seen between players with one
or two concussions within a four year time period. The amount of symptom complaints
increased significantly after one or two concussions, but symptom reports returned to
baseline by 10 days post-injury. Ives, Alderman, and Stred (2007) reported a 14 year old
patient that suffered four head traumas over a four month period. Two years later, the
patient was diagnosed with hypopituitarism. Currently, the patient is being treated with
physiologic replacement hormones with resumption of linear growth and strength. Ives et
al. (2001) reported that hypopituitarism symptoms are often masked by trauma and post-
concussion symptoms and may not appear until months or years after the trauma.
Randolph (2001) also assessed multiple concussions, and reported that each traumatic
episode to the brain results in further depletion of the reserve capacity. This limits the rate
18. 13
and the degree in which functional recovery can occur. The depletion could have two
effects, including permanent loss of some neurocognitive functions resulting from repeated
trauma, and increased sensitivity to the effects of normal aging such as premature
Parkinson disease or Alzheimer disease. However, Macciocchi et al. concluded that
neurocognitive and neurobehavioral consequences of only two concussions did not appear
to be significantly different from those of one concussion. Because of the limitations on
data interpretation, additional studies are needed to clarify the neuropsychological
consequences of multiple concussions (Macciocchi et al., 2001).
Neuropsychological Testing
According to Prentice (2006), neuropsychological testing is a type of assessment
that focuses on short-term memory, working memory, attention, concentration, visual
spatial capacity, verbal learning, information processing speed, and reaction time.
Neuropsychological testing has been developed for use in both on-field and off-field
evaluation. Computerized neuropsychological testing programs were developed and are
being utilized in the athletic setting today. According to Prentice, these computerized tests
show great success for eliminating some of the logical challenges of baseline testing, while
testing hundreds of athletes simultaneously. Therefore, computerized neuropsychological
testing has the potential to make a significant contribution to concussion management
(Prentice, 2006).
According to Barr (2001), neuropsychological testing is a proven method for
evaluating symptoms of a concussion. Applying these neuropsychological tests to athletes
has required some procedural modifications, including the use of brief test batteries,
collection of pre-season data, and evaluation of subtle postconcusive changes in test scores
24. 19
practice effects, the need for alternate forms, ease of administration, time efficiency, and
cost. The CRI uses specific measures of cognitive functions associated with
postconcussion syndrome including memory, reaction time, speed of decision making, and
speed of information processing. (See Appendix B) Six subtests are administered at
baseline and again post-trauma at each evaluation. These six subtests include three speeded
test indices and two error scores. Two subtests that make up the Processing Speed index
include Animal Decoding and Symbol Scanning. Animal Decoding is when athletes are
instructed to type in numbers keyed to animals and pictures. Symbol Scanning is where
athletes must rapidly determine whether identified sets of symbols are present among a set
of distractors. Reaction time is measured when athletes press the space bar when a target
shape appears on the screen, and Cued Reaction Time is measured when an athlete presses
the space bar when a target shape appears immediately after the “cue”. These subtests
comprise the Simple Reaction Time index. An error index is calculated based on total false
positives and false negatives. Visual Recognition 1 and Visual Recognition 2 present a
series of pictures, with some pictures repeated. Athletes must press the space bar as quickly
as possible whenever they recognize a picture from a previous exposure. An error index is
calculated based on total false positive and false negative responses on these two tests
(Erlanger et al., 2001).
Erlanger et al. (2001) conducted a study that was designed to determine the
usefulness in detecting and monitoring resolution of symptoms after sport-related
concussion, and to verify whether the CRI provides objective information for return-to-
play decisions. Neuropsychological baseline data was obtained on all subjects using the
CRI. The CRI was designed to compare an athlete’s post-concussion performance with
26. 21
test using the CRI during the pre-season, and took a follow-up test one day post-trauma.
The athlete scored significantly lower on the Simple and Complex Reaction Time indices.
The athlete reported to be asymptomatic at eight days post-trauma, while her performance
on the Simple and Complex Reaction time indices remained significantly lower than her
baseline performance, indicating she was still symptomatic. The athlete denied any re-
emergence of symptoms, and matched preseason scores at 14 days post-trauma, which
signify that the CRI successfully monitored her recovery. Broglio and Ferrara et al. (2007)
recommend neurocognitive evaluation to continue to be part of a multifaceted concussion
assessment program, with priority given to those scores showing the highest reliability.
Although the CRI is a relatively new test, the test shows to be an effective tool
when making return-to-play decisions. The test should not be used by itself, but should be
used in conjunction with the athlete’s self reporting of symptoms and the grading of a
concussion to determine when an athlete can return-to-play. However, additional research
is recommended.
Standardized Assessment of Concussion (SAC)
According to Valovich et al. (2003), the Standardized Assessment of Concussion
(SAC) is a mental status test designed to assess cognitive and postural stability that takes
about five to seven minutes to administer. McCrea (2001) stated that the SAC was
developed to give clinicians a more objective and standardized method of immediately
assessing an injured athlete’s mental status on the sport sideline within minutes of a mild
head injury. The instrument is designed to be a supplement to other methods of concussion
assessment, but not designed to be individually used to determine the severity of a head
injury or determine when an athlete may return-to-play. The SAC consists of measures of
27. 22
orientation, immediate memory, concentration, and delayed recall, all totaling a composite
score of 30. (See Appendix C) According to Valovich McLeod, Barr, McCrea, and
Guskiewicz (2006), orientation is assessed by asking the athlete the day, week, month,
year, and time. A list of five unrelated words is used to measure immediate memory, and
the athlete is asked to repeat those five words three different times throughout the
evaluation. Repeating strings of numbers in the reverse order of their readings and the
months backwards is used to assess concentration. A neurological assessment is conducted
to assess strength, sensation, and coordination following a concussion. The presence of
loss of consciousness, retrograde amnesia, and post-traumatic amnesia are also
documented (McCrea, 2001). Valovich McLeod et al. (2006) assessed the test-retest
reliability and the reliable change of concussion assessments in athletes participating in
youth sports. Secondary objectives included SAC and neuropsychological assessments in
young athletes. Valovich McLeod et al. found that test-retest reliability using the SAC was
relatively low, so it is hypothesized that the SAC assesses other areas of cognitive function.
This proves that other neuropsychological tests must be used in conjunction with the SAC
to provide the most effective results (Valovich McLeod et al. 2006).
In a study done by McCrea (2001), 1325 high school and collegiate football players
were tested at baseline on the SAC. Sixty three injured subjects were evaluated
immediately on the SAC following their injury. These subjects were matched with 55
uninjured subjects that were randomly reexamined on the SAC. Once the subject had
sustained a concussion, both the subject and their respective match were tested on the
sideline, and again 48 hours post-injury under the same conditions. McCrea found a
decrease of more than four points on the SAC immediately post-trauma in the concussed
28. 23
athlete. However, uninjured subjects retested on the sideline showed an average increase of
one point above their baseline. McCrea found the SAC to be a valuable tool for
practitioners when detecting the immediate effects of concussion on mental status and
return-to-play decision making. However, McCrea noted that screening tools should not be
used as a replacement for medical evaluation or as the sole determinant about whether an
athlete is ready to return-to-play.
Hopefully an athlete will not suffer repeated concussions. Nonetheless, Valovich et
al. (2003) assessed whether repeated administration of the SAC demonstrates a practice or
learning effect in 32 uninjured high school athletes. Sixteen subjects were randomly
assigned to a control group, and the other 16 were randomly assigned to a practice group.
All subjects were administered the SAC at an initial test session to serve as a baseline
score. However, the results differed from McCrea (2001), who noted slight improvement
with normal controls from baseline to 48 hours after baseline. The results found on the
SAC did not have a practice effect on repeated administration between baseline and day 30
in both the practice group and the control group. Therefore, Valovich et al. (2003) stated
that athletic trainers should be confident that repeated administration of the SAC does not
elicit practice effects in healthy athletes and should be used to assess the mental status of
an athlete immediately following a concussion. However, Valovich et al. (2003) noted that
using three different forms of the SAC can help decrease practice effects and increase the
accuracy of results.
Oliaro, Anderson, and Hooker (2001) recommend certified athletic trainers and
team physicians to show consistency when using appropriate grading scales. Assessment of
concussion should include a symptom checklist, BESS, and SAC. The results should be
29. 24
compared with the athlete’s normal baseline scores, and neuropsychological and postural
stability testing should be administered at follow-up. Oliaro et al. concluded that return-to-
play decisions should be based on the grade of concussion, scores on objective tests, and
concussion symptoms during exertional activities.
The SAC was found to be a valuable instrument when immediately assessing a
concussion and determining return-to-play. The reliability of the test did not appear to
decrease with repeated administration. However, it is recommended that the athlete use a
different form of the test to help decrease learning effects. The test is not designed to be
used as the sole determinant when making return-to-play decisions, but the SAC is an
effective tool when combined with the athlete’s self reporting of symptoms and the grading
of the concussion.
Return-to-Play Guidelines
Determining whether an athlete is ready to return-to-play is a difficult decision for
an athletic trainer. According to Lovell et al. (2004) the diagnosis and management of a
concussion in athletes has become a highly debated topic in athletics. Recognition of the
potential dangerous effects of a concussion has progressed to multiple concussion
management guidelines over the past decade. These guidelines have emphasized the
importance of the presence, absence, and duration of the signs and symptoms of a
concussion. (See Table 3.) The criteria have provided valuable assistance to team medical
personnel and have lead to a greater degree of caution in managing the injury. However,
these guidelines have not undergone scientific validation, and there is controversy
regarding their effectiveness when predicting return-to-play (Lovell et al., 2004).
30. 25
Table 3. Guidelines for Returning to Play After Repeat or Recurrent Concussions (Prentice, 2006)
Classification Grade First Concussion Second Concussion Third Concussion
Colorado Medical 1(mild) RTP if asymptomatic RTP if Terminate season;
Society 20 minutes asymptomatic RTP if asymptomatic
Guidelines 1 week 3 months
2 (moderate) Terminate play; RTP Terminate season; Terminate season;
if asymptomatic RTP if asymptomatic RTP next season
1 week if asymptomatic
3 (severe) Terminate play; RTP in 2 weeks if Terminate season;
RTP 1 month if asymptomatic for no RTP in contact
asymptomatic 1 sports
week
Cantu Grading 1 (mild) RTP 1 week if RTP 2 weeks if Terminate season;
Scale asymptomatic asymptomatic RTP next season if
1 week asymptomatic
2 (moderate) RTP if asymptomatic Minimum 1 month; Terminate season
2 weeks RTP if asymptomatic next season if
1 week asymptomatic
3 (severe) Minimum 1 month; Terminate season; No further contact;
RTP if asymptomatic RTP if asymptomatic RTP next season if
1 week asymptomatic
American 1 (mild) Terminate play; Terminate play;
Academy of RTP 15 minutes if RTP if asymptomatic
Neurology asymptomatic 1 week
2 (moderate) Terminate play; Terminate play; RTP
RTP 1 week if if asymptomatic
asymptomatic 2 weeks
3 (severe) Terminate play; Terminate play;
RTP 1 week if RTP if asymptomatic
brief LOC; 2 weeks 1 month
with prolonged LOC
RTP= return-to-play; LOC= loss of consciousness; and Asymptomatic= no post concussive
symptoms.
Recent concussion management guidelines suggest that athletes sustaining a mild
concussion may return-to-play if asymptomatic for 15 minutes (Lovell et al., 2004). These
researchers assessed the utility of a current concussion management guideline in
classifying and managing mild concussions. Forty-three high school athletes completed
neuropsychological test performance and symptom ratings prior to the season at two times
during the first week following a mild concussion. Thirty six hours post-concussion,
31. 26
mildly concussed high school athletes demonstrated a decline in memory and a dramatic
increase in self-reported symptoms compared to baseline performance. Lovell et al. found
that athletes with a mild concussion demonstrated memory deficits and symptoms that
persisted to be worse than anticipated.
In the previous study it was noted that symptoms were worse than anticipated for a
mild concussion. In Kersey’s (1998) study, the researcher analyzed the possible
relationship between a reported mild concussion and an acute subdural hematoma in a
football athlete. A healthy athlete sustained a mild concussion, and continued symptoms
led to the diagnosis of post-concussion syndrome. Twenty five days following the
concussion, the athlete returned to play and sustained a second head injury 10 days later.
The athlete became unconscious and presented with abnormal posturing, a fixed and
dilated left pupil, shallow breathing, and right-sided paralysis. Kersey reported that a
recent concussion may increase the risk of a catastrophic injury. This case demonstrates the
importance of using concussion grading scales and adhering to return-to-play guidelines.
In addition, Kersey also recommends the use of additional diagnostic techniques to help
prevent an athlete from returning to participation too quickly.
Although an athlete may suffer a mild concussion, return-to-play guidelines are
established for the safety of the athlete. Collins, Lovell, and Mckeag (1999) reported a 25
year old hockey player that received an elbow to the face. Initially, the athlete reported
confusion the first one to two minutes, but denied a headache, nausea, dizziness, and did
not lose consciousness. After 30 minutes, the athlete reported nausea, dizziness, and had an
abnormal feeling, while he also performed poorly on the memory component of a mental
status evaluation. According to return-to-play guidelines, the athlete would return-to-play
32. 27
within 20 minutes post-injury, if not immediately. Clearly his later signs and symptoms
suggested a severe injury. Data suggest that current mild concussion return-to-play
recommendations that allow for immediate return-to-play may be too liberal (Collins et al.,
1999).
As the guidelines state, an athlete should not return-to-play until they are
asymptomatic. An article by King (1996) stated that a range of post-concussion symptoms
are often reported after injuries, including headaches, dizziness, fatigue, irritability, double
vision, and depression. Patients with mild or moderate head injuries are usually
asymptomatic within three months of their injury. According to Kelly (2001), the
observation of loss of consciousness at the time of concussion must be viewed as reflecting
a potentially mild traumatic brain injury. This is different than a mild concussion. Loss of
consciousness is followed by more severe acute mental status abnormalities and has an
increased risk of intracranial pathology than concussion without loss of consciousness.
Collins et al. (1999) reported a 19 year old running back that made helmet to helmet
contact with a linebacker. The athlete had loss of consciousness for five seconds, and
walked off the field under his own power. The athlete reported no related symptoms and
passed a mental status examination immediately following the injury, at five, 10, and 15
minute intervals. Kelly (2001) reported that prolonged loss of consciousness represents a
neurological emergency, which may require neurosurgical intervention. Therefore,
lingering symptoms of a concussion, even without loss of consciousness, should be
monitored closely and managed according to established guidelines for safe return-to-play
(Kelly, 2001). However, Collins et al. (2003) reported the presence of amnesia, not loss of
consciousness, appears predictive of symptom and neurocognitive deficits. Athletes
35. 30
further injury. Therefore, neuropsychological and neurocognitive testing are valuable tools
when used in conjunction with self reported symptoms, and the grading of the concussion.
Return-to-play guidelines are valuable to practitioners. The criteria have lead
athletic trainers to error on the side of caution when managing a concussion. However,
these guidelines have the tendency to focus on loss of consciousness and amnesia. The
latest research shows that these factors are not the only predictors of the severity of injury.
All grading scales vary when determining an athlete’s readiness for return-to-play.
Therefore, additional research regarding the return-to-play guidelines is warranted to
improve consistency.
Although there was no formal literature found, it is within the athletic trainer’s
scope of practice to refer all concussions to a physician in order to rule out a catastrophic
head injury. Allowing an athlete to return-to-play too quickly may result in second impact
syndrome. Therefore, neuropsychological and neurocognitive tests should be used in
conjunction with the return-to-play guidelines, the self reporting of signs and symptoms,
and the grading of the concussion in order to return an athlete to play as safely as possible.
36. 31
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