Sport-related+Concussion+Diagnosis

__Pathophysiology __

The American Academy of Neurology's (AAN) definition for concussion is a trauma-induced alteration in mental status that may or may not involve loss of consciousness. Concussion is a mild form of TBI, meaning it is more transient and usually not life-threatening. Severe TBIs can have long-term or permanent effects. [33] The AAN describes 3 grades of concussion.
 * Definition **

No loss of consciousness Concussion symptoms or mental status abnormalities resolve in less than 15 minutes || No loss of consciousness Concussion symptoms or mental status abnormalities last more than 15 minutes ||
 * American Academy of Neurology Concussion Grading Scale ||
 * Grade 1 || Transient confusion
 * Grade 2 || Transient confusion
 * Grade 3 || <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Any loss of consciousness ||

<span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">A concussion occurs when the brain experiences a mechanical shake from rapid acceleration and deceleration from an impact to the head or the body. Even a "ding" or "getting your bell rung" can cause movement of the brain within the skull .[3] <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> Forces are transmitted to the head immediately after impact and is followed by metabolic and mechanical changes. Research indicates changes begin with a calcium overload, which elicits a sudden increase in energy demand to re-establish the pre-trauma ionic balance. Oxidative stress leads to mitochondrial dysfunction, so there is an imbalance between ATP consumption and production. Neurons must work harder for glycolysis, but this pathway is not efficient and does not fulfill the energy requirement .[28]
 * <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Br<range type="comment" id="418286956_2">ain Changes</range id="418286956_2"> **

<span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">So: General metabolic depression = subsequent cognitive deficits.

<span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Changes appear in the white matter skeleton mainly in the anterior associative area and descending motor output tracts. These structures are in the prefrontal cortex, involving the frontal lobe, corona radiata, anterior thalamic radiation, and corpus callosum .[2] <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> The corona radiata is an arc of white matter connecting the superior cortex to deeper structures. The anterior thalamic radiation consists of fibers that connect thalamic nuclei and the cerebral cortex of the frontal lobe. The two hemispheres are connected by the millions of axons of the corpus callosum. This integrates motor, sensory, and cognitive functioning between cerebral cortex on either side of the brain. The prefrontal cortex is involved in memory, concentration, motor planning, higher-order concept formation, and retrieval of learned information .[34]
 * <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Cerebral Structures and Function **

<span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Though there are metabolic changes, structural damage is not normally seen on routine imaging .[25]

<span style="color: #d60093; font-family: Arial,sans-serif;"> The story of Phineas T. Gage describes the importance of the frontal lobe. He was a foreman on railroad construction in the mid-19th century. He was tamping an explosive in a hole drilled into rock with a 13 pound, 3 ½ foot long iron bar. The charge exploded unexpectedly as he was packing it in. The rod blew out of the hole and went through the front of his head. Large portions of Gage’s prefrontal cortex were destroyed, and although he physically recovered, his personality changed. Before, he was reliable, well-organized, and hardworking. After the accident, he was unreliable, impulsive, had little regard for consequences, and became an alcoholic and a hobo.[34] __ Well-Detailed and Entertaining Recap of the Famous Gage and His Brain __ media type="youtube" key="FrULrWRlGBA" height="315" width="560"
 * Prefrontal Cortex Woes **

<span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">When patients are admitted with a head injury, there is an issue whether to perform imaging tests, just observe, or discharge. Neurological observation tends to only be performed about 50% of the time on patients admitted with a mild head injury, with the rest being seen by non-specialist nurses and doctors. This causes more injuries to be misdiagnosed or undiagnosed. <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Undiagnosed head injuries are very serious because the brain becomes extremely vulnerable to permanent damage. If there is a second insult to the brain in close proximity to the first, the brain cells suffer irreversible damage and die. There is incomplete resolution of the initial energetic crisis and the metabolic effects are prolonged. There is evidence that two close, mild injuries can simulate the effects of a single severe injury .[28] <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">It is very important to use valid and reliable diagnostic tests soon after the impact, along with a neurological examination by a specialist and brain imaging, when a patient is suspected of having a head injury.
 * <span style="color: #008000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Importance of Diagnosis **

__<span style="color: #e3860a; font-family: Tahoma,Geneva,sans-serif; font-size: 140%;">Types of Activities causing Dx __
 * <span style="color: #e3860a; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Concussions, or mild traumatic brain injuries (mTBI), in adolescents are most commonly seen in athletes. The prevalence of concussions varies depending on sport and gender. The highest proportions of concussions are found in contact sports when compared to noncontact sports. The highest incidence includes football, girls’ soccer, boys’ wrestling, and girls’ basketball. In gender-comparable sports girls had higher rates of concussion than boys. <span style="color: #e3860a; font-family: Tahoma,Geneva,sans-serif;">[18]

__ Epidemiology __
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Conservative estimate: 300,000 sport-related concussions per year in United States
 * *Due to no definitive diagnosis of concussion since there is an inconsistent uniformity of signs and symptoms [5]
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Mechanism of Injury:
 * Males: player to player contact
 * Females: contact with playing surface or equipment [27]
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Age-specific:
 * Estimated 62, 816 concussions occur annually in high school students, with football accounting for approximately 63% of the cases
 * Based on 2011 reported by the NCAA’s Injury Surveillance System, the number of concussions in college sports increased from 7% from 1988 to 2004 [6]
 * Number of concussions per 1000 athletic exposures in practice and competition:
 * High School football: 0.47 versus College football: 0.61
 * *Most likely due to college medical infrastructure ability to perform concussion tests [11]
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sports-specific:
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Number of concussions per 1000 athletic exposures in practice and competition:
 * Women’s Ice hockey (0.91); Men’s football (0.54), Men’s Ice hockey (0.41); Women’s soccer (0.41)
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Highest Percentages of concussion in all injuries recorded:
 * <span style="color: #3b98e3; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Women’s Ice hockey (18.3%); Men’s Ice Hockey (7.9%); (Women’s Lacrosse 6.3%); Men’s Football (6.0%) [11]

__ Subjective Symptoms/Signs __ <span style="color: #ff00ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The general sign of concussion is short-lived impaired neurological function that resolves spontaneously. Acute clinical symptoms are characterized by functional disturbances rather than structural changes, and due to a lack of abnormalities on standard neurological imaging studies. 90% of cases do not involve LOC or obvious signs of concussion .[28] <span style="color: #ff00ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The CDC has issued [|guidelines] that are convenient for use on the sideline during any sporting activity. <span style="color: #ff00ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">It is important to remember that you cannot “see” a concussion, and some athletes may not experience or report symptoms for hours or days after injury .[3] <span style="color: #ff00ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The brain should return to normal within 7-10 days from a mild concussion; however adolescents tend to require more time for recovery than adults .[33]

__ <range type="comment" id="418286956_3">Diagnostic Tests</range id="418286956_3"> __


 * ImPACT ** (Immediate Post-Concussion Assessment and Cognitive) self-administered, computer-based, baseline and post-concussion test consisting of demographic, symptom, and neuropsychological inventory ImPACT Description


 * Assesses cognitive functioning components such as attention, memory, processing speed, and reaction time which are translated into four outcomes measures: verbal memory, visual memory, visual-motor speed, and reaction time [5]


 * Positive Response: Yields multiple indicators sensitive to a concussion. The test compares a post-injury test to baseline test or normative values. ImPACT has normative data to compare post-injury test to if baseline test is absent. A diagnostic decision requires the addition of a medical personnel evaluation. [26]

>
 * Sensitivity: 81.9%
 * Specificity: 89.4%
 * Schatz, Pardini, Lovell, Collins, and Podell's (2006) study compiled results of concussed high school athletes to age-matched athletes whom had no history of concussion. The study did not confirm a concussed injury by a radiographic test in athletes and post-concussion testing was performed within 72 hours of injury.

**<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">King-Devick Test **
<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The King-Devick test is a measurement of rapid number naming that can be administered in less than 2 minutes. It is used to catch impairments in eye movement, attention, language, and other factors that may be associated with suboptimal brain function. This rapid sideline screening tool is used mainly for athletes that may have just experienced a concussion during play.[8][9][17]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Technique: The King-Devick Test involves reading a series of numbers aloud from three different test cards. The subject is asked to read each card from left to right, top to bottom as fast as possible without making errors. The sum of the 3 test card time scores makes up the summary score for the total King-Devick test. The test does not require athletic trainers or medical professionals to administer which is a useful feature for all ages of athletic sports. It may be presented to the athlete via hard copy, IPad or other readable electronic device.[8][9][17]

<span style="color: #0087ff; font-family: Tahoma,Geneva,sans-serif; font-size: 90%;">Following completion of the demonstration card (upper left), subjects are then asked to read each of the 3 test cards in the same manner. The times required to complete each card are recorded in seconds using a stopwatch. Numbers of errors made in reading the test cards are also recorded; misspeaks on numbers are recorded as errors only if the subject does not immediately correct the mistake before going on to the next number.[32]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Positive Response Description: If the athlete’s summary time score is any longer than the baseline time score performed by the athlete before play, this would display a positive test response and the athlete should be immediately removed from play until examined by a licensed professional for a concussion.[32]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sensitivity/Specificity/Reliability/Validity: The King-Devick test has been shown to have high test-retest reliability. It is sensitive to harmful effects of concussion on visual tracking.[8]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"><range type="comment" id="418286956_4">Demonstration video</range id="418286956_4">: [] media type="youtube" key="hGcz0dQUZnw" height="315" width="560"

Standardized Assessment of Concussion- SAC [15, 21] <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The SAC is an objective and standardized method of immediately assessing an athlete’s mental status on the sideline within minutes of having sustained a concussion during activity. It measures the most common cognitive domains where deficits are noted after a head injury: orientation, immediate memory, neurologic screening, loss of consciousness, concentration, delayed recall, strength, sensation, coordination, exertion, and amnesia.

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Administration: Athletic trainer or other medical personnel has the athlete answer the questions and perform the functions from the card on the sideline immediately after suspected injury. Takes 5 minutes to perform, and a total score is calculated to quantify the athlete’s overall level of impairment. Compare the score to the athlete’s baseline score (if no baseline is available, a generalized “normal” score can be used, but this is not as effective)

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">+ Response: a change in score from baseline

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sensitivity: 95% (patient with a concussion will be correctly identified) <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Specificity: 76% (patient without concussion will be correctly classified as not having one) <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Validity/Reliability: Research shows there is no significant difference between scores observed during practice and actual games, which assures that ‘game stress’ does not affect test scores. Baseline testing can provide a valid and reliable marker against which to detect change from an injury during games.

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Additional Pros:1) SAC is a quantifiable and objective test so it is able to help decide the appropriate management of the athlete's injury and aid in assessing readiness for return to play. 2) 3 alternate forms of the test allow re-assessment while minimizing adverse practice effects. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">[|FORM A] <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">[|FORM B] <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">[|FORM C]


 * <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 140%;">Sport Concussion Assessment Tool 2 (SCAT2) **

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The Sport Concussion Assessment Tool (SCAT) was originally created in 2004. SCAT was the first tool developed that combined many aspects of concussion testing into one evaluation including symptoms, memory, attention span, and concentration abilities. In 2009, because SCAT did not contain a balance assessment tool or a standardized scoring system, the CIS conference changed SCAT to the Sport Concussion Assessment Tool 2 (SCAT2) to address these shortcomings. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif;">[24] <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> The SCAT2 is the most recently developed assessment tool and is also the longest to implement, requiring approximately 20 minutes to administer. Often SCAT2 is used in the training room to confirm sports-related concussions after a concussion was suspected using other sideline tests. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif;">[15]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Technique: There are 6 different sections with the number of items equaling the number of points that section is worth. The first is a 22-item (and therefore 22 point) symptom scale. The second section is a 2-item score assessing loss of consciousness and balance deficits. The third is the Glasgow Coma Scale (GCS) with 15 items that measures eye, verbal, and motor response. The Standardized Assessment of Concussion (SAC) is the fourth part with 30 items, determining orientation, immediate memory, concentration, and delayed memory. The modified Balance Error Scoring System (BESS) to assess balance worth 30 points. The final part is the coordination evaluation worth 1 point. If the SCAT2 is being used as a sideline assessment the Maddocks questionnaire is administered and scored separately. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif;">[24]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Positive Response: The test has 100 total points possible with higher scores representing healthy scores and lower scores representing impairment. There is no cutoff score for impaired or not impaired because this test is not comparing a person to a standard, rather comparing a person to their score prior to injury. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif;">[24]

<span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sensitivity/Specificity/Reliability/Validity: Due to the recent development of the SCAT2, there have been few studies with conclusive results for validity, reliability, sensitivity, and specificity. The fact that it includes existing tests such as the SAC (94% sensitive and 76% specific), BESS (34% sensitive and 91% specific), and Maddocks questions (32-75% sensitive and 86-100% specific) provide some face validity for SCAT2. Evidence shows that baseline scores vary depending on age, gender, and previous concussion history. This means that a perfect score of 100 is not appropriate for every person. Baseline scores for each individual should be obtained prior to participation in a sport. <span style="color: #0000ff; font-family: Tahoma,Geneva,sans-serif;">[24]

media type="youtube" key="7IlfH20NFp8" height="315" width="420" align="center"

__<span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 140%;">Outcome Measures __ <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Return to class <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Return to play
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Recognition and initial assessment of a concussion should be guided by a symptoms checklist, cognitive evaluation, balance tests and a neurological physical examination <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12] <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">. See Initial Evaluation of Concussion <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[27]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Imaging used only when intracerebral bleeding is suspected <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Balance disturbance is a has good specificity when diagnosing a concussion but is not very sensitive. Balance testing on the sideline may be substantially different than baseline tests because of different shoes or surface, use of tape or braces, and the possible presence of LE injury <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">There is NO same day return to play for an athlete diagnosed with a concussion <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Athletes suspected or diagnosed with a concussion should be monitored for deteriorating physical or mental status <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Neuropsychological (NP) tests are an objective measure of brain–behavior relationships and are more sensitive for subtle cognitive impairment than clinical exam <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Most concussions can be managed without the use of NP testing <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Written NP tests can be more comprehensive and are used to assess different domains and other conditions which may present as or complicate the assessment of a concussion <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">NP testing should be used only as part of a management plan for a concussion. It should not be used by itself <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Comprehensive NP evaluation is helpful in the post-concussion management of athletes with persistent/complicated symptoms <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Table 4 - Neurological Exam Findings <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[27]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Table 5 - Neurological Implication <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[27]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Students will require mental rest and need accommodations in school such as reduced work and extended time for tests while recovering from a concussion <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Concussion symptoms should be resolved before returning to exercise <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">A RTP progression involves a gradual increase in physical demands, sports-specific activities, and the risk for contact <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">If symptoms occur with activity, the progression of treatment should be stopped and the athlete should go back to a step where symptoms are not caused <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">RTP after concussion should occur only with medical clearance <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Graduated Return to Play Protocol <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[12]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Rehabilitation Stage || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Objective of Stage ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">No activity || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Recovery ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Light aerobic exercise || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Increase HR ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sport specific exercise || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Add Movement ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Non contact training drills || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Exercise, coordination and cognitive load ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Full contact practice || <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Restore athlete's confidence; coaching staff assesses functional skills ||
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Return to play ||  ||

<span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">It is not clear if all the repercussions that follow a concussion (eg, symptoms, cognition, balance) follow the same or different recovery patterns <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22] <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">. <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[27]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Study #1 **

<span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Study was done where 2410 player-seasons were analyzed <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">779 players were enrolled for more than 1 year of the study <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">94 players who sustained a concussion were enrolled in an extensive injury assessment protocol <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">A noninjured control was selected from each injured player's team based on age, years of education, and baseline performance on concussion assessment measures <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [22]
 * [[image:kumc-ptrs-ebp/table 2.png width="825" height="437"]]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 16px;">Table 2 summarizes the measures used to assess postconcussive symptoms, cognitive functioning, and postural stability <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 12px;">[22] <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 16px;">.
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Higher scores on the Graded Symptom Checklist (GSC) indicate more severe symptoms <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Lower scores on the Standardized Assessment of Concussion (SAC) indicate poorer cognitive performance <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Higher scores on the Balance Error Scoring System (BESS) indicate poor postural stability <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Error bars indicate 95% confidence intervals <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">CC: time of concussion, PG:postgame/postpractice <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Cognitive impairment in players with concussion was most severe at the time of injury and persisted through postinjury day 2 <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Milder cognitive deficits appeared to persist up to postinjury day 5 but, on average, resolved by day 7 <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Balance deficits were most pronounced during the first 24 hours after concussion but appeared to resolve by day 5 <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [22]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">It is important to note that the rate of recovery after concussion varies from player to player. The findings suggest that clinicians can't expect all collegiate football players will reach a complete recovery within 7 days. Approximately 10% of players in this study required more than a week for symptoms to fully go away. Also, not all players showed the same pattern of recovery <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[22].

<span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Looked at the following objective measures: structured interview, 4 memory measures, and concussion symptoms scale ratings <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;"> [7]
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Study #2 **
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Baseline and post injury scores along with multiple analyses of variance were used to compare recovery curves within and between groups
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Subjects: 370 m football and 23 f soccer (college); 161 m football and 22 m soccer (HS)
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">All participated in Concussion Safety Program
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Took a baseline neuropsychological test: age, position, college board exam scores, GPA, learning disabilities, neurologic history, psychiatric history, and history of concussion
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Concussions graded by American Academy of Neurology (AAN):
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">grade 1 - mental changes resolve in <15 min
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">grade 2 - >15 min
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">grade 3 - loss of consciousness
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 16px;">Likert scale <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 16px;">: 20 symptoms graded form 0-6 (the link is not the Likert scale that was used, just an example of what it could look like)
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">25 min of neuropsychologic tests: they took several different tests but the main two that were looked at were Hopkins Verbal Learning Test (verbal learning and memory) for the college athletes and Brief Visual Spatial Memory Test-Revised (BVMT-R) for high school athletes
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Scores were taken 24 hours, 3, 5, and 7 days after injury
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Performed MANOVA
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Results
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">53% had previous concussion; college had higher rate of multiple past concussions and higher number of total concussions; majority were mild concussions (grade 1 or 2)
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">HS may demonstrate slower acute neuropsychologic recovery after sports related concussion when compared to college
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Had significant memory impairment after 7 days
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">College only had significant memory deficits within the first 24 hours
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Self report is often used for return to play - may be inadequate because self report symptoms resolved within 3 days after injury but cognitive deficits lasted at least 7 days from the event. Athletes also reported fewer symptoms 5-7 days post injury than they did at baseline. This shows there is a strong possibility that they are underreporting symptoms. They could be under reporting symptoms because they don't understand the potential severity of the injury, they have a desire to return to play, or they believe they have to play through injuries to be tough <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[7] <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">.
 * <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Table 6 - Elements of Concussion Management <span style="color: #ff0000; font-family: Tahoma,Geneva,sans-serif;">[27]

__<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 140%;">Medical Tests __


 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 140%;">Magnetic Resonance Imaging (MRI) **

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">MRI techniques are widely used when diagnosing mTBI because they are sensitive to changes in white matter in the brain. Traditional MRI can detect some injuries to the brain but it misses the more subtle changes that occur with mTBI. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[10] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> Susceptibility-Weighted Imaging (SWI) and Diffusion Tensor Imaging (DTI) are two advanced types of MRI that are prevalent with mTBI diagnosis.

media type="youtube" key="usvd9sITSBM" height="315" width="560" align="center"
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Susceptibility-Weighted Imaging (SWI), also known as BOLD MRI, is a tool used to detect the amount and location of microhemorrhages within the brain in moderate to severe TBI. It uses a 3D gradient echo scan which is sensitive to venous blood, more specifically the final breakdown of blood hemosiderin. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[29] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> It should not be used in the acute phase of injury because blood takes days to weeks to break down into hemosiderin. This imaging is helpful with showing older injuries, so therefore should be used in the subacute/chronic stages. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[23]
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">In mTBI there is very little microhemorrhaging. Therefore, this tool may only be useful to subclassify mTBI into microhemorrhage positive or negative. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[31]

media type="youtube" key="6HZwCuN_P_0" height="315" width="420" align="center"
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Diffusion Tensor Imaging (DTI) is preferred over other neuroimaging tools such as traditional MRI and CT because it is more sensitive to slight changes in white matter that occur with mTBI. This is the most sensitive MR technique available for finding specific tract lesions after an mTBI. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[10] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;"> DTI works by taking measurements of water diffusion through axons. In white matter water moves along axons instead of across them, which means the direction of flow can be determined and quantified allowing for examination of axonal integrity. DTI uses many measurements of diffusion including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). FA measures the direction and amount of water diffusion from zero to one using fiber organization, axon diameter, and myelination. MD measures the overall rate of diffusion in all directions. AD measures axonal health by looking at diffusion along the principal axis of the tensor. RD measures myelin status by looking at diffusion orthogonal to the principal axis. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[1]
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Research has shown that in adolescent/pediatric populations with mTBI there is more of an inflammatory response when compared to adults and this leads to diffuse axonal injury in the white matter of the brain. DTI makes it possible to evaluate the extent of damage within days of the injury and track progress throughout recovery. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[1]
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Depending on the phase of healing and the patient group measured, these values can be increased or decreased in those with concussions. Adolescents with subacute sports-related concussion showed increased FA values and decreased MD, AD, and RD values when compared to controls. Furthermore, lower scores on the SCAT2 were also associated with these same values. <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif;">[1]

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Technique: An EEG is a pain free procedure that uses small metal electrodes attached to the scalp to detect electrical activity of the brain. Brain cells communicate via electrical impulses at all hours of the day. The electrical signals show up as wavy lines on an EEG. An EEG can help rule-in, rule-out or help manage sports concussions.[14] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Preparation for the test requires clean hair and scalp, no caffeine intake, and sleeping only a few hours the night before to ensure the patient will be relaxed during the test.[14] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">The procedure can take between 30-60 minutes.[14]
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 12pt;">Electroencephalography (EEG) **

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sensitivity/Specificity/Reliability/Validity/Test Threshold: Quantitative EEG’s have been shown to have high sensitivity (96.59%) and high specificity (89.15%) while also having a high positive predictive value (93.6%) and high negative predictive value (97.4%) for diagnosing mild TBI’s. The Quantitative EEG has also been noted as having high reliability.[30]

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Video: [] media type="youtube" key="C0OUex2piGc" height="315" width="560"

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Technique: A Computerized Tomography (CT) Scan is a series of X-rays taken at various angles to form cross-sectional “slices” of the soft tissue of interest (the brain). CT images can be combined to create 3-D images. CT scans would be considered a “step up” from plain x-rays. CT scans are not able to specifically diagnose concussions but rather are used more to rule-out more severe problems that can occur with a head injury, like a skull fracture or hematoma.[13]
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 12pt;">Computerized Tomography (CT) Scan **

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Videos: [] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">media type="youtube" key="gV-gX2e74_4" height="315" width="560" <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">[] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">media type="youtube" key="e-QwyZVMLSo" height="315" width="560"

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Technique: S100B is a protein usually found only in the brain. When there is a disruption in the Blood Brain Barrier (i.e. during a mild traumatic brain injury) S100B can be found in the blood. Once in the blood stream the body sees the protein as something foreign creating an autoimmune response to S100B. Since the Blood Brain Barrier is disrupted, the auto-antibodies are able to enter the brain via cerebrospinal fluid and cause permanent brain damage. A study recently performed by Marchi, N., et al. discussed that the higher the S100B blood levels were in collegiate football players the higher the number and severity of head hits they endured. Body contact or simply playing in a football game did not affect S100B levels in athletes. S100B blood levels is an objective way of diagnosing mild TBI’s in athletes with head trauma.[19] <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">
 * <span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 12pt;">S100B Protein **

<span style="color: #7030a0; font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">Sensitivity/Specificity/Reliability/Validity/Test Threshold: The S100B protein was found to have 94% sensitivity and 100% specificity.[20]

<range type="comment" id="418286956_5">Citations</range id="418286956_5">
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 * 2) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Borich, M., Makan, N., Boyd L., & Virji-Babul, N. (2013). Combining whole brain voxelwise analysis with in vivo tractography of diffusion behavior following sports related concussion in adolescents: a preliminary report. //Journal of Neurotrauma,// [Epub ahead of print]. PMID: 23406264
 * 3) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Center for Injury Prevention and Control. (2012). Concussion and mild TBI. Retrieved from Centers for Disease Control and Prevention website: http://www.cdc.gov/concussion/index.html
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