Concussion symptoms can differ for each patient, depending on the areas of the brain that are affected by the injury; however, certain symptoms of concussion are more common than others. The most common symptoms noted within the first week of injury are as follows:

EPIDEMIOLOGY OF CONCUSSION

Recent data from the Centers for Disease Control and Prevention (CDC) suggest that there are 1.6 to 3.8 million TBIs per year in the United States. Of these, the majority (75%–90%), can be classified as a mild TBI or concussion. Over 50% of TBIs occur in individuals less than 24 years of age. The highest peak incidence of TBI seen in emergency departments (EDs) across the country occurs in individuals aged 0 to 4 years, followed by those 15 to 19 years of age. Children aged 0 to 14 account for almost 500,000 ED visits for TBI across the country each year.

In the pediatric population, the majority of concussions occur during sports and recreational activities, making up almost 50% of all injuries. While sports-related injuries account for a large number of concussions, they are not the sole etiology. Other common etiologies include falls (25%), striking an object/person (10%), and motor vehicle accidents (10%).

In the past 10 years, the number of high school students who have been diagnosed with a concussion has risen significantly. This is likely due to more stringent monitoring and sideline assessments and greater community knowledge and education. Approximately 25% of high school students report having experienced one concussion and 20% have experienced two or more concussions. While the majority of research, discussion, and media buzz surround sports-related concussion, it is imperative that even nonathletes be properly diagnosed, evaluated, and treated.

SPORTS-RELATED CONCUSSION

The overall incidence of concussion in high school athletes is 24 per 100,000. Football consistently causes the highest number and percentage of concussions at the high school and college levels, ranging as high as nearly 75%. Ice hockey injuries are also quite common. In female athletes, soccer is the most common cause of concussion and is implicated in nearly 50% of cases (4,5). Injuries in lacrosse and field hockey are also fairly common, and the number of concussions diagnosed in cheerleaders is also on the rise.

In gender-comparative sports, such as soccer, females are more susceptible to concussion than their male counterparts. It is suspected that this is due to a number of factors including anatomic, psychosocial, and sociocultural differences. There are higher rotational velocity forces of the head on the neck in females. Due to the smaller neck size and lesser neck muscle mass, the head accelerates more quickly leading to increased forces at the gray–white matter junction. This axonal injury may contribute to the increased recovery time demonstrated in some female athletes compared to male athletes.

CONCUSSION EVALUATION

Acute Evaluation

All concussions require evaluation by a medical provider. The initial evaluation may be performed on the field by a coach or AT; however, if there is concern for a possible concussion, further evaluation should be conducted by a physician or another practitioner with concussion training. Whenever a player shows any sign of concussion, onsite evaluation is warranted. If sideline evaluation is not possible, the player should be removed from play and urgent evaluation by a licensed health care provider should be arranged.

There are several sideline assessment tools that are validated for use following concussion. These assessments are performed in an athlete with concern for possible concussion. Although developed as sideline tools, they are frequently used in the physician’s office as well. The most common sideline tool is the Sport Concussion Assessment Tool, edition 3 (SCAT-3), used for athletes aged 13 years and older, and the Child-SCAT-3, for those aged 5 to 12 years. This tool asks the athlete to report current symptoms from a checklist, and evaluates cognitive performance and balance. The cognitive assessment includes evaluation of orientation, memory and concentration.

For concussions that do not occur during sports or those that occur without an AT present, initial evaluations are typically conducted by a primary care provider or in the ED. There are several concussion red flags that warrant immediate attention in an ED setting to evaluate for more severe injury. These are listed in the following section, Red Flags.

Evaluation for concussion begins with history regarding the injury and documenting the presence of any red flags, which warrant a higher level of care. A full examination should be performed, paying particular attention to the neurologic examination. A fundoscopic examination is warranted as well. Balance assessment is performed during the initial and subsequent office visits. This includes Romberg, tandem gait, and tandem and single-leg stance, with eyes open and closed. Visual tracking observation is important in the setting of concussion. This includes smooth pursuits, saccades, vestibulo-ocular reflex (VOR), and optokinetic responses. Following injury to the vestibular system, impairments in VOR and report of dizziness particularly with motion are readily observed and noted.

If there are any red flags present, the child or adolescent should be evaluated in the ED setting and may require admission to the hospital to allow for frequent monitoring, neurologic checks, and treatment of symptoms. This may include intravenous (IV) medications for headache abortion or IV fluids and antiemetics for persistent emesis.

Red Flags

Worsening headache

Weakness, numbness, decreased coordination, slurred speech

Repeated vomiting

Appear very drowsy or cannot be awakened

Unequal pupil size

Post-traumatic seizure

Severe confusion

Increasing confusion, restlessness or agitation, unusual behavior

Loss of consciousness

Neuroimaging

Concussions are functional brain injuries and cannot be seen on computed tomography (CT) scan or MRI. Thus, these studies are not routinely recommended for all patients with concussion. Acute CT scan should be considered if there are any abnormalities on neurologic examination or if there is a loss of consciousness (see the list of red flags). The purpose of the CT scan is to evaluate for any underlying intracranial bleeding such as an epidural, subdural, or intraparenchymal hemorrhage.

During the recovery phase of concussion, MRI of the brain may be warranted, especially if the patient is not following the anticipated recovery pattern. MRI may reveal axonal injury or underlying individual factors, such as a Chiari malformation, which may predispose the patient to protracted symptoms.

Several recent studies have evaluated various other neuroimaging techniques, such as diffusion tensor imaging, functional MRI, and positron emission tomography (PET) scan, to determine whether there is any benefit to using these newer techniques earlier in the course of concussion. It is unclear at this time whether any of these techniques will affect treatment interventions or outcomes (6).

SECOND IMPACT SYNDROME

CONCUSSION MANAGEMENT

Physical activity, physiologic stress, and cognitive loads can exacerbate concussion symptoms and prolong recovery. Thus, the key to recovery after a concussion is rest. While most health care providers recognize the importance of physical rest following concussion, the concept of cognitive rest is only recently becoming part of the prescription for concussion treatment. A recent article, published in the Journal of Pediatrics, evaluated the effect of various degrees of cognitive rest on the length of concussion recovery (7). This study confirmed that full cognitive rest and relative cognitive rest following injury lead to shorter recovery times. Of note, this study does not mention full bed rest. In fact, other studies (8) refute the idea of full bed rest quoting prior studies, which demonstrate that bed rest in normal individuals can lead to postconcussive-like symptoms. Also after 3 days of bed rest, deconditioning begins and mood and sleep patterns may also begin to deteriorate especially in those individuals with pre-existing conditions. Full rest may lead to avoidance and fear of environments, which may trigger symptoms, which will only make the conditions harder to treat long term.

Physical and cognitive rest allows the brain to use most of its energy to focus on healing. By not requiring brain energy for cognitive and physical tasks, the brain is thought to be set up for quicker recovery, which is demonstrated in some, but not all, recent studies. During the initial phase of recovery, abortive headache medications may be utilized to make the patient more comfortable and allow for easier rest and a quicker return to and tolerance of normal physical and cognitive activities. Frequently, medications such as melatonin may be introduced if there are persistent sleep difficulties.

Although it is important to address all postconcussive symptoms, three main symptom areas should be focused upon to help improve speed of recovery. These include headaches, sleep disturbances, and mood difficulties. Effectively addressing these three areas seems to shorten the duration of the postconcussive period based on anecdotal evidence alone; however, no studies to date support this.

In our concussion clinic, we have found that a short course of a scheduled nonsteroidal anti-inflammatory drug (NSAID) may be beneficial to attain better control of headaches when rest alone does not work. Typically, after at least 1 week of constant daily headache, a trial of Naprosyn twice daily for 5 days will improve the headache intensity and/or frequency of headaches. This improvement of headaches is beneficial with transition back to school. After a 5-day course, the scheduled use of these medications should be stopped to prevent the occurrence of rebound headaches.

The use of neurocognitive testing during concussion recovery is becoming the standard of care. This testing helps demonstrate, along with baseline school performance, when cognitive recovery has occurred. This testing is more sensitive to subtle cognitive difficulties that may persist even after reaching full school demands. This will be discussed in more detail later in this chapter.

In addition to neurocognitive testing, several other tests and monitoring are utilized in the office. These include self-reported symptoms, objective balance assessments such as single-leg and tandem stance or more in-depth testing with standardized balance assessments, and assessment of visual tracking such as the King–Devick test, which looks at saccadic eye movements, smooth pursuits, and the vestibulo-ocular reflex. As each of these tests measures a separate area of concussion recovery, one test alone should not be depended upon to make all decisions regarding return to school and return to sports activities.

RETURN TO SCHOOL

Once tolerating half-time attendance, the progression to full days should begin. Typically accommodations will remain in place until the student is tolerating the day with accommodations. Accommodations may remain in place longer if the student continues to demonstrate active cognitive recovery on neurocognitive testing; however, this is determined on an individual basis.

RETURN TO SPORT

Return to play (RTP) after a concussion follows the guidelines established originally in Vienna in 2001, at the International Conference in Concussion in Sport (ICCS). This conference has taken place an additional three times to provide updates based on current evidence. These subsequent conferences focused on improving the evaluation, management, and RTP of concussed athletes. The most recent ICCS took place in Zurich in 2012 and, thus, the current RTP guidelines are sometimes referred to as the Zurich guidelines. In 2010, the American Academy of Pediatrics (AAP) published basic concussion management guidelines for children and adolescents, adapted from the ICCS recommendations that emphasized a graduated RTP protocol and the importance of having an athlete follow a stepwise progression in their return to sport (11).

A child or adolescent suspected of having a concussion should not be allowed to return to play on the day of injury. Prior to return, the child or adolescent should be completely symptom-free (or with baseline preinjury symptoms) with a normal examination and have successfully completed full return to school. When conducted, neurocognitive testing should also demonstrate that full cognitive recovery has occurred.

CONCUSSION RECOVERY

Evidence suggests that children and adolescents, who are still actively undergoing brain development, take longer to recover than adults. Several factors are postulated to contribute to this longer recovery pattern as demonstrated in recent studies. These include a larger head-to-body ratio, reduced neck and shoulder musculature, which allows greater forces to be transmitted to the head, a larger subarachnoid space within which the brain can shift, reduced myelination of the central nervous system (CNS) subjecting children to greater shearing forces, and differences in cerebral blood volume. Despite this prolonged recovery pattern compared to adults, the majority of children and adolescents will recover quickly and completely. Approximately 80% of patients with the first concussion will recover within the first 2 weeks following their insult, usually 7 to 10 days. An additional 10% to 15% of patients will recover within the next 2 weeks. There is a notable difference in recovery patterns for sports-related versus non-sports-related concussions. About 10% of athletes with sports-related concussions will have symptoms that persist beyond 2 weeks. In all concussions, persistent symptoms beyond 3 months warrant evaluation for other conditions, which may be contributing to a protracted recovery or which mimic postconcussive symptoms.

There are a number of risk factors that may increase the likelihood a child/adolescent will have symptoms lasting longer than this anticipated time frame. The strongest risk factors in meta-analyses have been prior concussion and female sex. Evidence suggests that underlying mood disturbance may be a strong predictive risk factor of prolonged concussion recovery. Underlying mood disturbance may be exacerbated as a direct result of a concussion or changes may occur as a result of alterations in daily activity. Therefore, mood must be addressed and monitored early since it may lead to prolonged postconcussive symptoms. Other risk factors include history of frequent or migraine headaches, learning disabilities including attention deficit hyperactivity disorder (ADHD), history of speech therapy, premorbid sleep difficulties, and a family history of migraine headaches or Alzheimer dementia.

Initial symptoms experienced within the first few days may correlate with length of recovery. Dizziness following concussion is a marker of poorer prognosis and prolonged recovery, especially if present on the field or at the time of injury. Dizziness at 2 weeks postinjury is the single predictor of persistent postconcussive syndrome 6 months after mild TBI (12); therefore, careful assessment and treatment of dizziness should begin early. Other contributors to early persistent dizziness include migraine headaches, cervical spine dysfunction, visual-perceptual dysfunction, and autonomic dysfunction, all of which can be addressed with therapies.

Other factors that predict slower recovery are the presence of retrograde amnesia, post-traumatic amnesia, higher initial symptom score, and mental status change lasting longer than 5 minutes. Very poor scores on neurocognitive testing, such as Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) testing, in at least three of four areas within the first 72 hours of injury are also predictive of prolonged symptoms. The presence of premorbid anxiety or depression or post-traumatic stress can increase the likelihood that recovery will be slow.

THERAPIES FOR CONCUSSION

Most commonly the referral to physical therapy is made for a submaximal aerobic program with a gradual progressive increase in intensity as tolerated by the patient. In addition to helping with recovery, it also helps to build the child’s or adolescent’s confidence and hopefully prevent the development of depressive or psychosomatic symptoms, which further slow recovery. In addition to an aerobic program, physical therapy should also address any vestibular deficits. This includes balance work and visual training exercises to improve these deficits. The goal of these exercises is to restore postural stability and dynamic gaze stability. Vestibular rehabilitation is most effective in patients whose headaches are adequately controlled.

If postconcussive symptoms are persistent beyond 3 weeks, however are not exacerbated by any degree of physical activity, then an alternate diagnosis should be explored. The most common alternate diagnoses that may mimic postconcussive syndrome include post-traumatic stress disorder, depression, migraine headache, or cervicogenic headaches/vestibular dysfunction (13). Physical therapy may also be warranted in these cases; however, the therapy prescription may be slightly different. A gross screen for cervicogenic dizziness is to demonstrate relief of this symptom with gentle cervical traction. Neck pain must also be present if this is the underlying cause of the dizziness. If cervicogenic dizziness is present, physical therapy should include cervical range of motion, manual therapy for segmental hypomobility, manual cervical traction, and deep cervical flexor isometric stabilization exercises.

In the setting of significant visual deficits, referral to occupational therapy should be made to further concentrate this effort on recovery. Occupational therapy also provides some cognitive rehabilitation to work on deficits as they impact school and daily activities. For more significant cognitive deficits, referral to speech and language pathology should be incorporated into the therapy program. Prior to referral to all therapies, the patient should have evaluation and screening for any noninjury factors such as mood changes or school avoidance, which may be leading to continued reporting of symptoms. Also, if not already started, referral for neuropsychological evaluation is recommended for all patients with persistent symptoms.

NEUROCOGNITIVE TESTING

Cognitive assessment is generally regarded as essential in the diagnosis and management of concussion, as delineated by the ICCS held in Zurich in 2008. The increased vulnerability of the adolescent athlete relative to adults is well recognized as to duration of symptoms and differential recovery pattern. Furthermore, the effect of repeat concussion, treatment options, school demands, restriction of exposure to risk (continued sports participation)—both during recovery and subsequently—and the potential effect on a developing brain (14) are all factors that argue for the role of neuropsychological assessment in the care of such patients. The nature of this type of testing will now be explored.

There are two primary approaches to assessment in concussion. These include traditional paper and pencil testing and computerized assessment. Traditional neuropsychological testing via pencil and paper typically carries acceptable reliability and validity and have demonstrated sensitivity in some areas to concussion effects (4). These types of tests, however, lack the sensitivity of computer-based assessment and do not lend themselves as easily to the type of repeated assessment as required in the monitoring of concussion (15). Further, they often lack alternate forms and therefore are subject to practice effects. Further, traditional tests often lack the ability to detect subtle changes in reaction time and speed of mental processing.

Thus, the relatively recent computerized testing assesses abilities typically disrupted by concussion. There are several advantages of the use of computerized testing. One is that the tests have alternate forms, which allows for serial testing at different points in time. The second is the relatively short testing time duration, which is typically under 30 minutes. Third, and perhaps most useful, is the ability to baseline individuals’ preinjury. This is particularly relevant to child athletes, who are at substantially higher risk for concussion.

There are several widely used computerized batteries that have norms within the pediatric population. The HeadMinder Concussion Resolution Index (CRI) (16) has norms for ages 18 to 22 and “under 18.” The latter refers to a normative sample down to age 13, with analysis yielding no difference in the scoring of adolescents from ages 13 to 18 (16). The CRI is an Internet-based platform with six subtests, taking 25 minutes to administer. It yields three scores: processing speed index, simple reaction time index, and complex reaction time index. Verbal (written) stimuli were specifically avoided, with all stimuli in a visual icon format to minimize error due to language disability or English-as-second-language issues.

ImPACT (1972) is available in Windows and Macintosh applications as well as through an online version. An on-field palm-based version is also available and includes a brief on-field mental status evaluation. It does use verbal stimuli, and there is reading involved in testing instructions, with a sixth grade required reading level (17). It has eight subtests in its current version and registers demographic/history data, current concussion details (including information about anterograde and retrograde amnesia), as well as somatic and cognitive symptoms. There are four scores from ImPACT: verbal memory, visual memory, reaction time, and visuomotor speed. ImPACT has norms for ages 10 and above. Adolescent norms on this battery are extensive, and there is extensive literature on its use. Though developed primarily for sports concussion management, it has recently been used to characterize concussions presenting to an emergency room (5). There also exists a Pediatric ImPACT, which is an adaptation of the ImPACT battery for children. This is normed for children aged 5 to 12 years old. It consists of seven subtests that mirror the traditional ImPACT subtests, but present the stimulus material such that it is more “kid friendly” and more appealing to children. Psychometric analyses have yielded strong developmental age effects, test–retest reliability, and reasonable internal consistency (18), according to the authors of the test.

The use of computerized assessment in concussion diagnosis and management is not without its weaknesses. First and foremost, the majority of the literature that publishes effectiveness of these tests often comes from the institutions or authors who developed the instrument. Therefore, it is important to look for authors who do not have connection with the instruction or company that developed the test to attempt to reduce bias. Examination of the literature in these specific areas can be difficult due to lack of peer-reviewed studies in this area; however, there are some studies that show the potential downfalls of using these tests.

An important consideration in the use of computerized testing is test–retest reliability. Test–retest reliability is estimated by performing the same test to the same subjects, under the same conditions, over different time intervals. One study examining computerized testing found that test–retest reliability was reported to be 0.82 for processing speed, 0.70 for simple reaction time, and 0.68 for complex reaction time during a 2-week test–retest period for the HeadMinder Concussion Resolution Index (19). Another study conducted by Register-Mihalik and colleagues (20) administered the ImPACT test along with several other traditional paper and pencil tests to college-age and high-school-age subjects. The subjects were assessed at three separate time intervals with approximately 1 day (24 hours) in between sessions. The weakest value was found for verbal memory, while the highest (0.71) was found for processing speed (20). Both of these studies demonstrate that while test–retest reliability is moderate, there is concern for this particular psychometric property among computerized testing when it is repeated to the same group of subjects. Both of these studies, however, tested subjects in very limited time intervals (24 hours to 2 weeks). The literature is sparse for time intervals longer than this; thus this continues to question the reliability of both ImPACT and HeadMinder. This also questions the effects and utility of serial testing in concussion assessment and management, as practice effects in these close time intervals raise questions.

Validity is also a major concern when it comes to neuropsychological testing, especially computer-based. Validity refers to whether a test is measuring what it is intended to measure. Most research to date has focused on the sensitivity of ImPACT results to a suspected postconcussive injury. The majority of the studies have administered ImPACT to concussed athletes and have compared the scores to baseline scores, control group, or age and gender norms. Symptomatic athletes indeed often produce postinjury scores that are lower than their baseline, yielding construct validity, as the test is sensitive to “history of recent concussion.” Most studies have also found, however, that measuring recovery is a complex matter that is often complicated by practice effects as well as other psychometric confounds that may result from serial testing (15), as mentioned previously.

There are other criticisms to the use of this testing outside of psychometric properties. First pre-existing cognitive issues, often deemed “exceptionalities,” such as a diagnosis of ADHD, a learning disability, psychiatric diagnoses, and/or a variety of adjustment issues can skew testing results. Baseline tests can also present with difficulties with interpretation due to situations where children are put in a group to test and are distracted by friends or not taking the test “seriously.” In other situations, children or adolescents may attempt to sandbag, or “trick the test” into yielding lowered scores, so that recovery may be judged sooner and that they may return to play (21). Given the variety of factors that may impair the interpretation of testing results, it is very important to include an experienced neuropsychologist as part of the multidisciplinary team when it comes to concussion management. Further, the need may arise for the neuropsychologist to conduct a more in-depth evaluation when assessing chronic symptoms, rather than strictly relying on screening tools (15).

Overall, there is a depth of literature that discusses both the benefits and downfalls of computerized neurocognitive testing as well as traditional neuropsychological testing in the assessment and management of concussion. It is important to note that, despite more advanced methods of testing cognition, no RTP decisions should ever be made on the use of neurocognitive testing alone. These judgments should be reached by the collaboration of a multidisciplinary team, which provides a more comprehensive picture of the patient’s functioning after an injury. There is not yet a gold standard for RTP decisions, and therefore all points of data, including physical examination, neurocognitive testing, self-reported symptoms, and assessment of environmental functioning should be considered in order to make appropriate decisions.