Sport-Related Concussion: On-Field and Sideline Assessment

Overview of Traumatic Brain Injury in American Football Athletes

OBJECTIVE

The aim of this review is to provide a summary of the epidemiology, clinical presentation, pathophysiology, and treatment of traumatic brain injury in collision athletes, particularly those participating in American football.

DATA SOURCES

A literature search was conducted using the PubMed/MEDLINE and Google Scholar databases for publications between 1990 and 2019. The following search phrases were used: "concussion," "professional athletes," "collision athletes," "mild traumatic brain injury," "severe traumatic brain injury," "management of concussion," "management of severe traumatic brain injury," and "chronic traumatic encephalopathy." Publications that did not present epidemiology, clinical presentation, pathophysiology, radiological evaluation, or management were omitted. Classic articles as per senior author recommendations were retrieved through reference review.

RESULTS

The results of the literature review yielded 147 references: 21 articles discussing epidemiology, 16 discussing clinical presentation, 34 discussing etiology and pathophysiology, 10 discussing radiological evaluation, 34 articles for on-field management, and 32 articles for medical and surgical management.

CONCLUSION

Traumatic brain injuries are frequent in professional collision athletes, and more severe injuries can have devastating and lasting consequences. Although sport-related concussions are well studied in professional American football, there is limited literature on the epidemiology and management of severe traumatic brain injuries. This article reviews the epidemiology, as well as the current practices in sideline evaluation, acute management, and surgical treatment of concussions and severe traumatic brain injury in professional collision athletes. Return-to-play decisions should be based on individual patient symptoms and recovery.

Comparison of Concussion Sideline Screening Measures Across Varying Exertion Levels Within Simulated Games

CONTEXT

Currently, there is no gold standard to evaluate the effect of varying game-like exertion states on Sport Concussion Assessment Tool 3rd Edition (SCAT-3) outcomes. Baseline assessments may occur before, during, or after physical activity, while postinjury evaluations predominantly occur following physical activity. Thus, clinicians may be comparing postinjury evaluations completed following exertion to baseline evaluations completed following varying levels of rest or exertion, which may not be a valid method for clinical decision making.

OBJECTIVE

To determine the effect of various physical exertion levels on sideline concussion assessment outcomes and reliability.

DESIGN

Within-subjects, repeated measures.

SETTING

Field.

PARTICIPANTS

Physically active participants (N = 36) who regularly participate in basketball activity.

INTERVENTION

Subjects participated in 2 simulated basketball games, completing a symptom checklist, Standardized Assessment of Concussion, and Balance Error Scoring System before game play, during halftime, and at the completion of each simulated game. Pulse rate was assessed as a proxy of physical exertion.

MAIN OUTCOME MEASURES

Total symptom, Standardized Assessment of Concussion, and Balance Error Scoring System scores.

RESULTS

Physical exertion did not significantly predict symptom, Standardized Assessment of Concussion, or Balance Error Scoring System scores, although a trend toward higher symptom scores was observed for females (ß = 0.03, P = .09). All assessments had poor to moderate reliability across sessions (.15 < interclass correlation coefficient [2,1] < .60).

CONCLUSION

Low- to moderate-intensity physical activity did not have a significant effect on clinical concussion sideline assessments; however, the low test-retest reliability observed prevents strong conclusions on these relationships. The poor overall reliability does not allow for clear recommendations for what state of baseline physical exertion (ie, rested or exerted) provides optimal data to make postinjury clinical decisions, although baseline concussion assessments completed at rest have the most valid and conservative normative values for injury comparison.

At-a-glance - Traumatic brain injury management in Canada: changing patterns of care

INTRODUCTION

With growing awareness about traumatic brain injuries (TBI), there is limited information about population level patterns of TBI care in Canada.

METHODS

We examined data from the Canadian Community Health Survey (years 2004, 2009, and 2014) among all respondents ages 12 years and older. TBI management characteristics examined included access to care within 48 hours of injury, point of care, hospital admission, and follow-up.

RESULTS

We observed that many Canadians sought care within 48 hours of their injury, with no changes over time. We found a significant decline in the proportion of Canadians opting to visit an emergency department (p = 0.03, all ages), and a significant increase in youth opting to visit a doctor's office (p < 0.01).

CONCLUSION

TBIs are an important and growing health concern in Canada. Care for such injuries appears to have shifted towards the use of health care professionals outside the hospital environment, including primary care doctors.

Review of Assessment Scales for Diagnosing and Monitoring Sports-related Concussion

Sports-related concussion has emerged as a public health crisis due to increased diagnosis of the condition and increased participation in organized and recreational athletics worldwide. Under-recognition of concussions can lead to premature clearance for athletic participation, leaving athletes vulnerable to repeat injury and subsequent short- and long-term complications. There is overwhelming evidence that assessment and management of sports-related concussions should involve a multifaceted approach. A number of assessment criteria have been developed for this purpose. It is important to understand the available and emerging diagnostic testing modalities for sports-related concussions. The most commonly used tools for evaluating individuals with concussion are the Post-Concussion Symptom Scale (PCSS), Standard Assessment of Concussion (SAC), Standard Concussion Assessment Tool (SCAT3), and the most recognized computerized neurocognitive test, the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). The strengths and limitations of each of these tools, and the Concussion Resolution Index (CRI), CogSport, and King-Devick tests were evaluated. Based on the data, it appears that the most sensitive and specific of these is the ImPACT test. Additionally, the King-Devick test is an effective adjunct due to its ability to test eye movements and brainstem function.

Evidence of dynamic visual acuity impairment in asymptomatic mixed martial arts fighters

AIM

The purpose of this study was to determine the amount of visual acuity loss with head movement in actively training mixed martial arts (MMA) fighters.

METHODS

Vestibulo-ocular reflex function of 22 asymptomatic, male MMA fighters (age = 29.2 ± 5.1) was assessed by taking the difference between static visual acuity and the dynamic visual acuity test, in both yaw and pitch planes.

RESULTS

The mean static visual acuity testing logMAR was -0.173 (standard deviation [SD] = 0.114). Mean dynamic visual acuity test values decreased with head movement to 0.196 logMAR (SD = 0.103) in yaw; p < 0.001, and to 0.283 logMAR (SD = 0.133) in pitch; p < 0.001.

CONCLUSION

MMA fighters had a decay, beyond normal ranges, in visual acuity during head movement. These decreases may suggest vestibulo-ocular reflex impairment and were unrelated to self-reported concussion history. These results should be cautiously interpreted since there was not a control group.

Relationship of Attention Deficit Hyperactivity Disorder and Postconcussion Recovery in Youth Athletes

OBJECTIVE

To investigate whether attention deficit hyperactivity disorder (ADHD) influences postconcussion recovery, as measured by computerized neurocognitive testing.

DESIGN

This is a retrospective case control study.

SETTING

Computer laboratories across 10 high schools in the greater Atlanta, Georgia area.

PARTICIPANTS

Immediate postconcussion assessment and cognitive testing (ImPACT) scores of 70 athletes with a self-reported diagnosis of ADHD and who sustained a sport-related concussion were compared with a randomly selected age-matched control group. Immediate postconcussion assessment and cognitive testing scores over a 5-year interval were reviewed for inclusion.

MAIN OUTCOME MEASURES

Postconcussion recovery was defined as a return to equivalent baseline neurocognitive score on the ImPACT battery, and a concussion symptom score of ≤7.

RESULTS

Athletes with ADHD had on average a longer time to recovery when compared with the control group (16.5 days compared with 13.5 days), although not statistically significant. The number of previous concussions did not have any effect on the rate of recovery in the ADHD or the control group. In addition, baseline neurocognitive testing did not statistically differ between the 2 groups, except in verbal memory.

CONCLUSIONS

Although not statistically significant, youth athletes with ADHD took on average 3 days longer to return to baseline neurocognitive testing compared with a control group without ADHD.

CLINICAL RELEVANCE

Youth athletes with ADHD may have a marginally prolonged recovery as indexed by neurocognitive testing and should be considered when prognosticating time to recovery in this subset of student athletes.

The King-Devick test for sideline concussion screening in collegiate football

PURPOSE

Sports-related concussion has received increasing attention as a result of neurologic sequelae seen among athletes, highlighting the need for a validated, rapid screening tool. The King-Devick (K-D) test requires vision, eye movements, language function and attention in order to perform and has been proposed as a promising tool for assessment of concussion. We investigated the K-D test as a sideline screening tool in a collegiate cohort to determine the effect of concussion.

METHODS

Athletes (n=127, mean age 19.6±1.2 years) from the Wheaton College football and men's and women's basketball teams underwent baseline K-D testing at pre-season physicals for the 2012-2013 season. K-D testing was administered immediately on the sidelines for football players with suspected head injury during regular games and changes compared to baseline were determined. Post-season testing was also performed to compare non-concussed athletes' test performance.

RESULTS

Concussed athletes (n=11) displayed sideline K-D scores that were significantly higher (worse) than baseline (36.5±5.6s vs. 31.3±4.5s, p<0.005, Wilcoxon signed-rank test). Post-season testing demonstrated improvement of scores and was consistent with known learning effects (35.1±5.2s vs. 34.4±5.0s, p<0.05, Wilcoxon signed-rank test). Test-retest reliability was analyzed between baseline and post-season administrations of the K-D test resulting in high levels of test-retest reliability (intraclass correlation coefficient (ICC)=0.95 [95% Confidence Interval 0.85-1.05]).

CONCLUSIONS

The data show worsening of K-D test scores following concussion further supporting utility of the K-D test as an objective, reliable and effective sideline visual screening tool to help identify athletes with concussion.

Acute sports-related traumatic brain injury and repetitive concussion

Concussions are described as functional, not structural injuries, and therefore cannot be easily detected through standard diagnostic imaging. The vast differences between individual athletes makes identifying and evaluating sport-related concussion one of the most complex and perplexing injuries faced by medical personnel. The literature, as well as most consensus statements, supports the use of a multifaceted approach to concussion evaluation on the sideline of the athletic field. Using a standardized clinical examination that is supported by objective measures of concussion-related symptoms, cognitive function, and balance provides clinicians with the ability to track recovery in an objective manner. When used in combination, these tests allow for more informed diagnosis and treatment plan, which should involve a graduated return to play progression. Establishing a comprehensive emergency action plan that can guide the on-field management of a more serious and potentially catastrophic brain injury is also essential. This review will address these management issues, as well as the recent concerns about the risk of long-term neurologic conditions believed to be associated with repetitive concussion.

National Athletic Trainers' Association position statement: management of sport concussion

OBJECTIVE

To provide athletic trainers, physicians, and other health care professionals with best-practice guidelines for the management of sport-related concussions.

BACKGROUND

An estimated 3.8 million concussions occur each year in the United States as a result of sport and physical activity. Athletic trainers are commonly the first medical providers available onsite to identify and evaluate these injuries.

RECOMMENDATIONS

The recommendations for concussion management provided here are based on the most current research and divided into sections on education and prevention, documentation and legal aspects, evaluation and return to play, and other considerations.