Grade 1 or "ding" concussions in high school athletes

Musculoskeletal injury or Sports-Related Concussion (SRC) in a season of rugby union does not affect performance on concussion battery testing in university-aged student-athletes

BACKGROUND

Sub-concussive and concussive impacts sustained during contact sports such as rugby may affect neurocognitive performance, vestibular-ocular-motor function, symptom burden and academic ability.

METHOD

Student-athletes (n = 146) participating in rugby union British Universities or domestic competitions were assessed on the Immediate Post-Concussion and Cognitive Test, Post-Concussion Symptom Scale, vestibular-oculo-motor screening tool and revised perceived academic impact tool. Individual change from pre-season (July-September 2021) to 2-weeks following last exposure to contact (April-July 2022) was analysed.

RESULTS

Symptom burden significantly worsened (p=0.016) over the season. Significant improvements on verbal memory (p=0.016), visual memory (p=0.008) and motor processing speed (p=0.001) suggest a possible learning effect. Surprisingly, the number of days lost to concussion significantly and positively affected performance on verbal memory (p = 0.018) and reaction time (p = 0.027). Previous concussive events significantly predicted a worsening in symptom burden (p < 0.028), as did in-season concussive events, predicting improved verbal memory (p = 0.033) and symptom burden change (p = 0.047). Baseline performance significantly affected change on several neurocognitive tests, with low-scorers showing more improvement over the season.

CONCLUSION

Participation in rugby union was not associated with deleterious effects on brain function. Previous concussive events and in-season factors, possibly related to learning effects, may explain improvement in cognitive function across the season.

Psychometric Properties of Computerized Cognitive Tools and Standard Neuropsychological Tests Used to Assess Sport Concussion: A Systematic Review

Athletic programs are more frequently turning to computerized cognitive tools in order to increase efficiencies in concussion assessment. However, assessment using a traditional neuropsychological test battery may provide a more comprehensive and individualized evaluation. Our goal was to inform sport clinicians of the best practices for concussion assessment through a systematic literature review describing the psychometric properties of standard neuropsychological tests and computerized tools. We conducted our search in relevant databases including Ovid Medline, Web of Science, PsycINFO, and Scopus. Journal articles were included if they evaluated psychometric properties (e.g., reliability, sensitivity) of a cognitive assessment within pure athlete samples (up to 30 days post-injury). Searches yielded 4,758 unique results. Ultimately, 103 articles met inclusion criteria, all of which focused on adolescent or young adult participants. Test-retest reliability estimates ranged from .14 to .93 for computerized tools and .02 to .95 for standard neuropsychological tests, with strongest correlations on processing speed tasks for both modalities, although processing speed tasks were most susceptible to practice effects. Reliability was improved with a 2-factor model (processing speed and memory) and by aggregating multiple baseline exams, yet remained below acceptable limits for some studies. Sensitivity to decreased cognitive performance within 72 h of injury ranged from 45%-93% for computerized tools and 18%-80% for standard neuropsychological test batteries. The method for classifying cognitive decline (normative comparison, reliable change indices, regression-based methods) affected sensitivity estimates. Combining computerized tools and standard neuropsychological tests with the strongest psychometric performance provides the greatest value in clinical assessment. To this end, future studies should evaluate the efficacy of hybrid test batteries comprised of top-performing measures from both modalities.

Quantifying head impacts and neurocognitive performance in collegiate boxers

Head impacts and neurocognition were quantified in 27 intercollegiate male boxers engaged in two, two-minute sparring rounds. Head impacts were measured using Instrumented Boxing Headgear (IBH). Pre and post-sparring neurocognitive performance was compared using two computerized neuropsychological test batteries (CNTs): Immediate Post-concussion Assessment and Cognitive Testing (ImPACT™) and Automated Neuropsychological Assessment Metrics - Military Battery (ANAM4® MIL). An average of 27.63 ± 17.87 impacts above the 9.6 g IBH threshold were recorded per boxer, with average peak linear acceleration of 23.48 ± 15.20 g and average peak rotational acceleration of 1761.40 ± 1064.34 rad/s². Small, but measurable declines in delayed memory and improvement in response time from pre- to post-bout were noted. Number of impacts and concussion history predicted degraded memory performance. This is a runique quantificationof head impacts in collegiate boxing, which were similar in frequency and location, but lower in magnitude as compared to amateur boxing. Improved understanding of impact kinematics may enhance safety in boxing and other contact sports. Subtle post-bout decrements in delayed memory performance and mild improvement in response time reinforce prior research and provide evidence of congruence in our two CNT assessments, which may facilitate comparisons of outcomes across settings utilizing these tests.

Top-100 Most-Cited Sports-Related Concussion Articles Focus on Symptomatology, Epidemiology, and Demographics

Purpose

To analyze the top-100 cited articles on sports-related concussions together with a bibliometric analysis to determine citations by year, level of evidence, study design, and several other factors related to the top referenced articles in sports concussions.

Methods

The Clarivate Analytics Web of Knowledge database was used to gather data using Boolean queries to capture all possible iterations of sports-related concussion research. Articles were organized in descending order based on the number of citations and included or excluded based on relevance to concussion. Collected information included author name, publication year, country of origin, journal name, article type, study focus, and the level of evidence.

Results

The top-100 articles were cited 31,197 times with an average of 312.0 citations per publication. More than one half were published in 2006 or later (52). Cohort studies and descriptive articles were the most prevalent study types (22 each). Studies with Level V evidence were the most common (33). The most common areas of study were symptomatology (short term, long term) with 17 articles, followed by epidemiology/demographics with 16 articles. The least common area of study was concussion prevention (2 articles), followed by management/treatment, diagnostics (labs, imaging) with 4 articles each.

Conclusions

We identified the most influential studies in sports-related concussion based on number of citations and citation density. A majority of these articles were published in the United States after 2006 and are most commonly cohort studies (Level IV evidence) and descriptive articles (Level V evidence). Current research focuses most heavily on the symptomatology and epidemiology/demographics of sports concussion.

Clinical Relevance

This study serves to identify the most influential articles in sports-related concussion and identify research topics with general deficiencies within the field of sports-related concussion research.

Association between sports participation history and age of first exposure to high-risk sports with concussion history

The purpose of this study was to examine the association between sports participation history, including estimated age of first exposure (eAFE) to high-risk sports, and concussion history in first year (i.e., freshmen) collegiate athletes. Athletes increased their odds of sustaining a pre-college concussion by 5% [odds ratio(OR) = 1.05 (95%CI:1.05-1.06)] for each additional year of contact sports participation - 24% of all student athletes reported one or more pre-college concussions. When eAFE was analysed dichotomously at age 12, a greater proportion of those who started playing football before age 12 reported a positive concussion history compared to those who started playing football at age 12 or later (Х² = 4.483, p = 0.034, Phi = 0.049). When eAFE was analysed continuously, later eAFE to women's high-risk sports was associated with a lower likelihood of sustaining a pre-college concussion [OR = 0.93 (95%CI:0.88-0.98)]. Our findings suggest that there is a relationship between eAFE to football and to women's high-risk sports and concussion history.

Risk Factors for Vestibular and Oculomotor Outcomes After Sport-Related Concussion

OBJECTIVE

To investigate the association between risk factors and vestibular-oculomotor outcomes after sport-related concussion (SRC).

STUDY DESIGN

Cross-sectional study of patients seen 5.7 ± 5.4 days (range 0-30 days) after injury.

SETTING

Specialty clinic.

PARTICIPANTS

Eighty-five athletes (50 male athletes and 35 female athletes) aged 14.1 ± 2.8 years (range 9-24 years) seeking clinical care for SRC.

INTERVENTIONS

Participants completed a clinical interview, history questionnaire, symptom inventory, and vestibular/ocularmotor screening (VOMS). Chi-square tests with odds ratios and diagnostic accuracy were used to examine the association between risk factors and VOMS outcomes.

MAIN OUTCOME MEASURES

The VOMS.

RESULTS

Female sex (χ2 = 4.9, P = 0.03), on-field dizziness (χ2 = 7.1, P = 0.008), fogginess (χ2 = 10.3, P = 0.001), and post-traumatic migraine (PTM) symptoms including headache (χ2 = 16.7, P = 0.001), nausea (χ2 = 10.9, P = 0.001), light sensitivity (χ2 = 14.9, P = 0.001), and noise sensitivity (χ2 = 8.7, P = 0.003) were associated with presence of one or more postconcussion VOMS score above clinical cutoff. On-field dizziness (χ2 = 3.8, P = 0.05), fogginess (χ2 = 7.9, P = 0.005), and PTM-like symptoms including nausea (χ2 = 9.0, P = 0.003) and noise sensitivity (χ2 = 7.2, P = 0.007) were associated with obtaining a postconcussion near-point convergence (NPC) distance cutoff >5 cm. The likelihood ratios were 5.93 and 5.14 for VOMS symptoms and NPC distance, respectively.

CONCLUSIONS

Female sex, on-field dizziness, fogginess, and PTM symptoms were predictive of experiencing vestibular-oculomotor symptoms/impairment after SRC.

Web-Based Exercise Program Increases Cervical Strength in Adolescent Athletes

ABSTRACT

Wilson, JC, Levek, C, Daoud, AK, Brewer, M, Brooks, K, Sochanska, A, Randall, M, and Provance, AJ. Web-based exercise program increases cervical strength in adolescent athletes. J Strength Cond Res 35(4): 1149-1155, 2021-This cohort study aimed to evaluate the efficacy of a web-based 6-week cervical strengthening program on cervical strength in adolescent athletes. It was hypothesized that subjects completing the program would demonstrate significant increase in cervical muscle strength compared with baseline strength. Eighty-three high school soccer athlete subjects were recruited from 2 local nationally competitive soccer clubs. Teams were assigned to either control or intervention groups to minimize information crossover. Fifty subjects were recruited to the intervention group (29 male, 21 female; average age 15.1 years). Thirty-three subjects were recruited to the control group (21 male, 12 female; average age 15.1 years). Intervention group subjects completed a web-based progressive cervical strengthening program over 6 weeks. Cervical strength in flexion, extension, right and left lateral flexion (LLF) was measured in Newton (N) of force at 3 time points during the competitive season for both control and intervention groups. Intervention group subjects significantly increased cervical strength [mean difference (95% confidence interval)] in LLF [24.1 (15.9-32.4)], extension [27.9 (18.4-37.5)], right lateral flexion [18.8 (11.6-26.1)], and flexion [mean ratio: 1.2 (1.1-1.2)] at follow-up testing; whereas control subjects did not see significant changes in strength. A web-based progressive cervical strengthening program improves cervical muscular strength in a population of adolescent athletes over a period of 6 weeks. Such a program could be used by researchers in future studies evaluating the influence on concussion risk and by practitioners as a means of reducing sport-related head and neck injuries.

Reduced frontopolar brain activation characterizes concussed athletes with balance deficits

•

Symptomatic athletes with balance deficits present reduced frontopolar oxygenation during postural control with closed eyes.

•

Decreased brain oxygenation in the FPC of symptomatic individuals may characterize the deficit of shifting the focus from visual inputs towards proprioception.

Objectives

Athletes with sport-related concussions (SRC) often demonstrate deficits in postural stability. Lower cerebral blood flow in frontal cortices has been documented in athletes with symptoms after SRC, however, it is unclear if functional brain oxygenation during postural control tasks is reduced in symptomatic athletes after SRC in the same manner. We therefore compared brain oxygenation patterns in frontal cortices of symptomatic and asymptomatic athletes with SRC during postural control tasks with the hypothesis that symptomatic athletes are characterized by reduced functional brain oxygenation during postural control.

Methods

62 concussed athletes (n = 31 symptomatic, n = 31 asymptomatic) were investigated during four postural control tasks with eyes closed versus eyes opened conditions and stable vs. unstable surface conditions. Brain oxygenation was assessed using functional NearInfraRed Spectroscopy (fNIRS) on frontopolar cortices of each hemisphere. Postural sway was measured by the analysis of ground reaction forces.

Results

Symptomatic athletes showed greater postural sway when compared to asymptomatic athletes during postural control, particularly during closed eyes and/or unstable surface conditions. Changes of oxygenated hemoglobin (∆HbO₂) within the left hemispheric frontopolar cortex were significantly reduced in symptomatic athletes when compared to asymptomatic athletes during the eyes closed condition. A stepwise linear regression analysis revealed that self-reported post-concussion symptoms such as headaches and sadness predict decreased brain oxygenation during postural control with closed eyes.

Conclusion

Symptomatic athletes with increased postural sway are characterized by decreased frontopolar brain oxygenation during postural control tasks, particularly during conditions with closed eyes. Because the frontopolar cortex showed to be involved in redistributing executive functions to novel task situations, we conclude that athletes with post-concussion symptoms suffer from a deficit in coordinating postural adjustments to balance control tasks with reduced sensory input.

Testing the hybrid battery approach to evaluating sports-related concussion in the National Hockey League: A factor analytic study

Objective: There has been an increased interest in the use of "Hybrid" neuropsychological test batteries to evaluate neurocognitive functioning prior to and following sports-related concussion. Typically, these test batteries include a combination of traditional "paper and pencil" (P&P) and computerized measures. The National Hockey League (NHL) employs a Hybrid approach consisting of ImPACT and a brief battery of P&P measures. The purpose of this paper was to examine the NHL's Hybrid model by means of factor analytic techniques in order to determine the extent to which the measures included in the battery are independent of each other or share common variance.Method: Principal components analyses with promax rotations were conducted on the P&P measures alone and when combined with ImPACT. A total of 360 recently concussed NHL players underwent testing using the combined hybrid battery.Results: A principal components analysis with promax rotation of the combined hybrid battery yielded 5 factors (Verbal Learning/Memory, Visual Learning/Memory, Processing Speed/Executive Functioning, Cued/Recognition Memory and Reaction Time/Speed). The factors appear to be relatively independent of each other with the P&P measures comprising the Verbal Learning/Memory, Visual Learning/Memory, and Processing Speed/Executive Functioning and ImPACT loading on the Cued/Recognition Memory and Reaction Time/Speed factors.Conclusions: These data provide support for the Hybrid model with evidence that the P&P measures and ImPACT do not measure the same domains of cognitive functioning. The clinical implications of the findings are discussed in detail.

The Epidemiology of Sport-Related Concussion: What the Rehabilitation Clinician Needs to Know

Sport-related concussion is common in full-contact and collision sports. Epidemiology studies use different types of surveillance systems and concussion definitions. Concussion incidence rates vary across age, sex, sport, and level of competition. Incidence rates are increasing, likely due to higher rates of reporting following improved knowledge and increased regulations. In this review, we summarize 7 key concepts related to concussion epidemiology: concussion definition, changes in concussion knowledge, reliability and accuracy of injury surveillance systems, conservative management and return to play, reliability of self-report, incidence of concussion across levels of play, and understanding the behaviors of players, coaches, and medical personnel from a multidisciplinary management perspective. J Orthop Sports Phys Ther 2019;49(11):768-778. doi:10.2519/jospt.2019.9105.

Second-Impact Syndrome

Sports-related injuries are among the more common causes of injury in adolescents that can result in concussion and its sequelae, postconcussion syndrome and second-impact syndrome (SIS). Students who experience multiple brain injuries within a short period of time (hours, days, or weeks) may suffer catastrophic or fatal reactions related to SIS. Adolescents are particularly susceptible to the dangers of SIS, and current return-to-play guidelines may be too lenient to protect a student from SIS. Any student with signs of a concussion should receive medical evaluation and not be allowed to return to play in the current game or practice. The role of the school nurse includes being knowledgeable about management of head injuries and return-to-play guidelines, providing follow-up for athletes who have concussions, and providing education on prevention and management of head injuries.

Investigation of strategies to improve concussion reporting in American football

While research on sport-related concussion has increased dramatically over the past decade, research investigating concussion reporting is in its early stages. The purpose of this project was to assess concussion reporting and work with stakeholders to develop and assess strategies to improve reporting. We used a multi-site, repeated measures design with three NCAA Division I football programs, including 223 athlete participants. A modified community-based participatory research (CBPR) approach was used to develop intervention strategies (Fall 2017 season) with stakeholders designed to increase concussion reporting intentions. Preseason and postseason surveys were administered to determine effectiveness. Main outcome measures included concussion knowledge, intervention effectiveness, and reporting intention measures. For all three programs, concussion knowledge was unrelated to reporting intentions. Two of the three programs implemented the intervention strategies and for these programs there was evidence that the interventions were effective. Specifically, athletes from these two programs perceived more support from coaches about reporting (P< 0.05; t= 2.83), received education more frequently (P< 0.05; t= 2.67), and reported being more likely to report concussion symptoms (P< 0.05; t= 2.14). Our study demonstrates that working with stakeholders to develop site-specific strategies to improve concussion reporting is an effective approach to help improve reporting behaviours.

Neurobiological effect of selective brain cooling after concussive injury

The search for effective treatment facilitating recovery from concussive injury, as well as reducing risk for recurrent concussion is an ongoing challenge. This study aimed to determine: a) feasibility of selective brain cooling to facilitate clinical symptoms resolution, and b) biological functions of the brain within athletes in acute phase of sports-related concussion. Selective brain cooling for 30 minutes using WElkins sideline cooling system was administered to student-athletes suffering concussive injury (n=12; tested within 5±3 days) and those without history of concussion (n=12). fMRI and ASL sequences were obtained before and immediately after cooling to better understanding the mechanism by which cooling affects neurovascular coupling. Concussed subjects self-reported temporary relief from physical symptoms after cooling. There were no differences in the number or strength of functional connections within Default Mode Network (DMN) between groups prior to cooling. However, we observed a reduction in the strength and number of connections of the DMN with other ROIs in both groups after cooling. Unexpectedly, we observed a significant increase in cerebral blood flow (CBF) assessed by ASL after selective cooling in the concussed subjects compared to the normal controls. We suggest that compromised neurovascular coupling in acute phase of injury may be temporarily restored by cooling to match CBF with surges in the metabolic demands of the brain. Upon further validation, selective brain cooling could be a potential clinical tool in the minimization of symptoms and pathological changes after concussion.

Concussions in Sports

Although concussions are common, they are complex, variable, and not entirely understood in terms of pathophysiology and treatment. The incidence of concussion is expected to continue to rise with the increased participation of youth in sports and improved awareness. The role of orthopedic surgeons in concussion management is murky. However, the existing literature does provide a foundation from which orthopedic surgeons who are exposed to concussed patients can function. [Orthopedics. 2019; 42(1):12-21.].

A review of sideline assessment measures for identifying sports-related concussion

Currently, there is a lack of clear, “gold standard” guidelines for the identification and management of sports-related concussion. This is of concern considering the importance of preventing further injury during game-play. Moreover, a number of assessment measures and tools aim to detect concussion in athletes and help inform return to play decisions, including the assessment of posture and balance, eye-saccades, memory, attention, orientation and post-concussive symptomatology. However, they have often not been widely disseminated for validity studies, and their utility or sensitivity in detecting concussion is limited due to a number of factors. As such, this review will examine current guidelines and sideline assessments measures which aim to inform decisions about return to play following sports-related concussion.

Effect of Enzogenol® Supplementation on Cognitive, Executive, and Vestibular/Balance Functioning in Chronic Phase of Concussion

This study examined the feasibility of Enzogenol® as a potential treatment modality for concussed individuals with residual symptoms in the chronic phase. Forty-two student-athletes with history of sport-related concussion were enrolled, comparing Enzogenol® versus placebo. Testing was conducted using virtual reality (VR) and electroencephalography (EEG), with neuropsychological (NP) tasks primarily used to induce cognitive challenges. After six weeks, the Enzogenol® group showed enhanced frontal-midline theta, and decreased parietal theta power, indicating reduced mental fatigue. Subjects enrolled in the Enzogenol® group also self-reported reduced mental fatigue and sleep problems. This suggests that Enzogenol® has the potential to improve brain functioning in the chronic phase of concussion.

Recovery progression and symptom resolution in sport-related mild traumatic brain injury

OBJECTIVE

To characterize the recovery progression of a group of athletes who participated in a concussion management program based on (1) group analysis and (2) individual analysis.

SETTING

Concussion management clinic.

PARTICIPANTS

Thirty athletes (22 males, 8 females; baseline age = 16.23 ± 2.40 years) who had undergone four assessments: one baseline and three post-injury assessments at 3, 8, 15 days post-injury.

DESIGN

Retrospective clinical.

MAIN MEASURES

Four neurocognitive scores of the Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) including verbal memory, visual memory, speed of processing and reaction time and also a total symptom score.

RESULTS

Group-analysis showed a clear decline in verbal memory (F(3, 87) = 7.36, p < 0.000) and an increase in self-reported symptoms (χ²(3, N = 30) = 48.703, p < 0.000), 3 days post-injury. By day 8, athletes had returned to their baseline levels for verbal memory and were not experiencing symptoms. When athletes' scores were examined individually, at 3 days post-injury, 60% of the athletes showed deficits on two or more of the ImPACT variables. This rate dropped to 23% at 8 days post-injury and remained the same (23%) 15 days post-injury.

CONCLUSIONS

In concussion recovery, variability is the rule, rather than the exception, with regard to both impaired neurocognitive functions and recovery duration.

Age of first exposure to American football and long-term neuropsychiatric and cognitive outcomes

Previous research suggests that age of first exposure (AFE) to football before age 12 may have long-term clinical implications; however, this relationship has only been examined in small samples of former professional football players. We examined the association between AFE to football and behavior, mood and cognition in a large cohort of former amateur and professional football players. The sample included 214 former football players without other contact sport history. Participants completed the Brief Test of Adult Cognition by Telephone (BTACT), and self-reported measures of executive function and behavioral regulation (Behavior Rating Inventory of Executive Function-Adult Version Metacognition Index (MI), Behavioral Regulation Index (BRI)), depression (Center for Epidemiologic Studies Depression Scale (CES-D)) and apathy (Apathy Evaluation Scale (AES)). Outcomes were continuous and dichotomized as clinically impaired. AFE was dichotomized into <12 and ⩾12, and examined continuously. Multivariate mixed-effect regressions controlling for age, education and duration of play showed AFE to football before age 12 corresponded with >2 × increased odds for clinically impaired scores on all measures but BTACT: (odds ratio (OR), 95% confidence interval (CI): BRI, 2.16,1.19-3.91; MI, 2.10,1.17-3.76; CES-D, 3.08,1.65-5.76; AES, 2.39,1.32-4.32). Younger AFE predicted increased odds for clinical impairment on the AES (OR, 95% CI: 0.86, 0.76-0.97) and CES-D (OR, 95% CI: 0.85, 0.74-0.97). There was no interaction between AFE and highest level of play. Younger AFE to football, before age 12 in particular, was associated with increased odds for impairment in self-reported neuropsychiatric and executive function in 214 former American football players. Longitudinal studies will inform youth football policy and safety decisions.

A Comparative Meta-Analysis of the Effects of Concussion on a Computerized Neurocognitive Test and Self-Reported Symptoms

CONTEXT

  Meta-analyses examining construct-specific cognitive impairment concurrently with self-reported symptoms postconcussion are sparse.

OBJECTIVE

  To review the literature on the effects of concussion on construct-specific neurocognitive declines and to compare them with self-reported symptoms before 1 week and between 1 and 3 weeks postconcussion.

DATA SOURCES

  Relevant studies in PubMed, CINAHL, and PsycINFO published from January 1, 1999 through November 30, 2015.

STUDY SELECTION

  Studies were included if participants completed the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) before and after concussion and if test performance and Postconcussion Symptom Scale (PCSS) scores were reported at both times.

DATA EXTRACTION

  After reviewing the full texts, we extracted data from 17 studies consisting of 29 independent samples; therefore, this meta-analysis consisted of 1777 unique participants.

DATA SYNTHESIS

  The Hedges g effect size (ES) was estimated. A random-effects or fixed-effects model was used based on heterogeneity findings. When heterogeneity was present, we used meta-regression to assess unexplained between-studies variance. Within the first week of injury, the ESs were small to moderate for cognitive declines, ranging from -0.43 (95% confidence interval [CI] = -0.52, -0.35) to -0.67 (95% CI = -0.77, -0.58), and large for the PCSS score (Hedges g = -0.81; 95% CI = -0.91, -0.71). After 1 week, the ESs for cognitive declines (Hedges g range = -0.25 [95% CI = -0.35, -0.15] to -0.37 [95% CI = -0.55, -0.19]) and PCSS score (Hedges g = -0.38; 95% CI = -0.53, -0.22) were also small. Within 2 weeks of injury, PCSS score and time since injury weakly moderated the cognitive ES.

CONCLUSIONS

  When a neurocognitive test was administered within 1 week of injury, the ES was larger for self-reported symptoms than for ImPACT scores generated at the same session. After 1 week of injury, the ESs for ImPACT and PCSS scores were comparable. If the athlete reports symptoms within 1 week of injury, administering a cognitive test does not appear to offer additional information to the clinician. However, if the athlete does not report symptoms postconcussion, cognitive testing may inform the clinical management of the injury.

Cumulative Effects of Concussion History on Baseline Computerized Neurocognitive Test Scores: Systematic Review and Meta-analysis

Context:

It is unclear whether individuals with a history of single or multiple clinically recovered concussions exhibit worse cognitive performance on baseline testing compared with individuals with no concussion history.

Objective:

To analyze the effects of concussion history on baseline neurocognitive performance using a computerized neurocognitive test.

Data sources:

PubMed, CINAHL, and psycINFO were searched in November 2015. The search was supplemented by a hand search of references.

Study Selection:

Studies were included if participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT) at baseline (ie, preseason) and if performance was stratified by previous history of single or multiple concussions.

Study Design:

Systematic review and meta-analysis.

Level of Evidence:

Level 2.

Data Extraction:

Sample size, demographic characteristics of participants, as well as performance of participants on verbal memory, visual memory, visual-motor processing speed, and reaction time were extracted from each study.

Results:

A random-effects pooled meta-analysis revealed that, with the exception of worsened visual memory for those with 1 previous concussion (Hedges g = 0.10), no differences were observed between participants with 1 or multiple concussions compared with participants without previous concussions.

Conclusion:

With the exception of decreased visual memory based on history of 1 concussion, history of 1 or multiple concussions was not associated with worse baseline cognitive performance.

Validity of the Immediate Post Concussion Assessment and Cognitive Testing (ImPACT)

BACKGROUND

The immediate post concussion assessment and cognitive testing (ImPACT) is the most widely used concussion assessment tool. Despite its popularity, it is unclear if validation studies for the ImPACT test covered all aspects of validity to support its widespread use in research and clinical practice.

OBJECTIVE

The purpose of this report is to review literature surrounding the validity and the utility of the ImPACT test.

DATA SOURCES AND APPRAISAL

A systematic review of relevant studies in PubMed, CINAHL, and PsycINFO was carried out. Studies were evaluated using the STROBE (strengthening the reporting of observational studies in epidemiology) or the STARD (standards for reporting of diagnostic accuracy) criteria.

RESULTS

The literature search yielded 5968 studies. Sixty-nine studies met the inclusion criteria and were included in the qualitative review. Although the convergent validity of ImPACT was supported, evidence of discriminant and predictive validity, diagnostic accuracy and responsiveness was inconclusive. The utility of the ImPACT test after acute symptom resolution was sparse. The review found many factors influenced the validity and utility of ImPACT scores.

CONCLUSION

Clinicians must consider the benefit of ImPACT testing for their patients on a case-by-case scenario and must take the psychometric properties of the test into account when interpreting results.

Predictors of clinical recovery from concussion: a systematic review

OBJECTIVE

A systematic review of factors that might be associated with, or influence, clinical recovery from sport-related concussion. Clinical recovery was defined functionally as a return to normal activities, including school and sports, following injury.

DESIGN

Systematic review.

DATA SOURCES

PubMed, PsycINFO, MEDLINE, CINAHL, Cochrane Library, EMBASE, SPORTDiscus, Scopus and Web of Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies published by June of 2016 that addressed clinical recovery from concussion.

RESULTS

A total of 7617 articles were identified using the search strategy, and 101 articles were included. There are major methodological differences across the studies. Many different clinical outcomes were measured, such as symptoms, cognition, balance, return to school and return to sports, although symptom outcomes were the most frequently measured. The most consistent predictor of slower recovery from concussion is the severity of a person's acute and subacute symptoms. The development of subacute problems with headaches or depression is likely a risk factor for persistent symptoms lasting greater than a month. Those with a preinjury history of mental health problems appear to be at greater risk for having persistent symptoms. Those with attention deficit hyperactivity disorder (ADHD) or learning disabilities do not appear to be at substantially greater risk. There is some evidence that the teenage years, particularly high school, might be the most vulnerable time period for having persistent symptoms-with greater risk for girls than boys.

CONCLUSION

The literature on clinical recovery from sport-related concussion has grown dramatically, is mostly mixed, but some factors have emerged as being related to outcome.

What is the difference in concussion management in children as compared with adults? A systematic review

AIM

To evaluate the evidence regarding the management of sport-related concussion (SRC) in children and adolescents. The eight subquestions included the effects of age on symptoms and outcome, normal and prolonged duration, the role of computerised neuropsychological tests (CNTs), the role of rest, and strategies for return to school and return to sport (RTSp).

DESIGN

Systematic review.

DATA SOURCES

MEDLINE (OVID), Embase (OVID) and PsycInfo (OVID).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they were original research on SRC in children aged 5 years to 18 years, and excluded if they were review articles, or did not focus on childhood SRC.

RESULTS

A total of 5853 articles were identified, and 134 articles met the inclusion criteria. Some articles were common to multiple subquestions. Very few studies examined SRC in young children, aged 5-12 years.

SUMMARY/CONCLUSIONS

This systematic review recommends that in children: child and adolescent age-specific paradigms should be applied; child-validated symptom rating scales should be used; the widespread routine use of baseline CNT is not recommended; the expected duration of symptoms associated with SRC is less than 4 weeks; prolonged recovery be defined as symptomatic for greater than 4 weeks; a brief period of cognitive and physical rest should be followed with gradual symptom-limited physical and cognitive activity; all schools be encouraged to have a concussion policy and should offer appropriate academic accommodations and support to students recovering from SRC; and children and adolescents should not RTSp until they have successfully returned to school, however early introduction of symptom-limited physical activity is appropriate.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2016:CRD42016039184.

A case matched study examining the reliability of using ImPACT to assess effects of multiple concussions

BACKGROUND

Approximately 3.8 million sport and recreational concussions occur per year, creating a need for accurate diagnosis and management of concussions. Researchers and clinicians are exploring the potential dose-response cumulative effects of concussive injuries using computerized neuropsychological exams, however, results have been mixed and/or contradictory. This study starts with a large adolescent population and applies strict inclusion criteria to examine how previous mild traumatic brain injuries affect symptom reports and neurocognitive performance on the Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) computerized tool.

METHODS

After applying exclusion criteria and case matching, 204 male and 99 female participants remained. These participants were grouped according to sex and the number of previous self-reported concussions and examined for overall differences on symptoms reported and scores obtained on the ImPACT neurocognitive battery composites. In an effort to further reduce confounding factors due to the varying group sizes, participants were then case matched on age, sex, and body mass index and analyzed for differences on symptoms reported and scores obtained on the ImPACT neurocognitive battery composites.

RESULTS

Case matched analysis demonstrated males with concussions experience significantly higher rates of dizziness (p = .027, η² = .035), fogginess (p = .038, η² = .032), memory problems (p = .003, η² = .055), and concentration problems (p = .009, η² = .046) than males with no reported previous concussions. No significant effects were found for females, although females reporting two concussions demonstrated a slight trend for experiencing higher numbers of symptoms than females reporting no previous concussions.

CONCLUSIONS

The results suggest that male adolescent athletes reporting multiple concussions have lingering concussive symptoms well after the last concussive event; however, these symptoms were found to be conflicting and better explained by complainer versus complacent attitudes in the population examined. Our results conflict with a significant portion of the current literature that uses relatively lenient inclusion and exclusion criteria, providing evidence of the importance of strict inclusion and exclusion criteria and examination of confounding factors when assessing the effects of concussions.

Predicting Outcome 12 Months after Mild Traumatic Brain Injury in Patients Admitted to a Neurosurgery Service

Objective

Accurate outcome prediction models for patients with mild traumatic brain injury (MTBI) are key for prognostic assessment and clinical decision-making. Using multivariate machine learning, we tested the unique and added predictive value of (1) magnetic resonance imaging (MRI)-based brain morphometric and volumetric characterization at 4-week postinjury and (2) demographic, preinjury, injury-related, and postinjury variables on 12-month outcomes, including global functioning level, postconcussion symptoms, and mental health in patients with MTBI.

Methods

A prospective, cohort study of patients (n = 147) aged 16–65 years with a 12-month follow-up. T1-weighted 3 T MRI data were processed in FreeSurfer, yielding accurate cortical reconstructions for surface-based analyses of cortical thickness, area, and volume, and brain segmentation for subcortical and global brain volumes. The 12-month outcome was defined as a composite score using a principal component analysis including the Glasgow Outcome Scale Extended, Rivermead Postconcussion Questionnaire, and Patient Health Questionnaire-9. Using leave-one-out cross-validation and permutation testing, we tested and compared three prediction models: (1) MRI model, (2) clinical model, and (3) MRI and clinical combined.

Results

We found a strong correlation between observed and predicted outcomes for the clinical model (r = 0.55, p < 0.001). The MRI model performed at the chance level (r = 0.03, p = 0.80) and the combined model (r = 0.45, p < 0.002) were slightly weaker than the clinical model. Univariate correlation analyses revealed the strongest association with outcome for postinjury factors of posttraumatic stress (Posttraumatic Symptom Scale-10, r = 0.61), psychological distress (Hospital Anxiety and Depression Scale, r = 0.52), and widespread pain (r = 0.43) assessed at 8 weeks.

Conclusion

We found no added predictive value of MRI-based measures of brain cortical morphometry and subcortical volumes over and above demographic and clinical features.

Clinical Evaluation of the Concussed Athlete: A View From the Sideline

CONTEXT

The sideline assessment of concussion is challenging, given its variable presentations, the limited sensitivity and specificity of sideline assessment tools, and how the presentation of the injury evolves over time. In addition, the diagnostic process, as well as the tools used to assess and manage concussion, continue to progress as research and what we know about concussion advance. This paper focuses on the initial assessment on the sideline by reviewing the concussion-evaluation literature, drawing from clinical experience to emphasize a standardized approach, and underscoring the importance of both familiarity with the athlete and clinical judgment.

OBJECTIVE

To review the evidence regarding the clinical assessment of sport-related concussion on the sideline. Additional considerations included making same-day return-to-play decisions, the sensitivity and specificity of sideline testing, and the importance of ongoing assessment and follow-up of injured athletes.

DATA SOURCES

I conducted a systematic literature review of the assessment of concussion on the sideline. The PubMed and MEDLINE databases were searched using the key term athletic injuries with concussion and mild traumatic brain injury. The search was refined by adding the key terms sideline assessment and on-field assessment. In addition, select additional position statements and guidelines on concussion were included in the review.

RESULTS

The PubMed search using athletic injuries and concussion as key terms produced 1492 results. Refining the search by sideline assessment and on-field assessment produced 29 and 35 results, respectively. When athletic injuries and traumatic brain injury were combined, 1912 results were identified. Refining the search by sideline assessment and on-field assessment led to 28 and 35 results, respectively. Only papers that were English-language titles, original work, and limited to human participants and included sideline assessments of sport-related concussion in athletes older than 13 years were considered for this discussion. A total of 96 papers were reviewed, including systematic reviews, consensus guidelines, and position statements.

CONCLUSIONS

The sideline assessment of sport-related concussion is challenging given the elusiveness and variability of presentation, reliance on athlete-reported symptoms, and the varying specificity and sensitivity values of sideline assessment tools. In addition, the recognition of injury and assessment often occur in a time-pressured environment, requiring rapid disposition and decision making. Clinicians should begin the evaluation by assessing for cervical spine injury, intracranial bleeding, and other injuries that can present in a similar fashion or in addition to concussion. The sideline concussion evaluation should consist of a symptom assessment and a neurologic examination that addresses cognition (briefly), cranial nerve function, and balance. Emerging tools that assess visual tracking may provide additional information. The sensitivity and specificity of commonly implemented sideline assessment tools are generally good to very good, especially for symptom scores and cognitive evaluations performed within 48 hours of injury, and they are improved when a baseline evaluation is available for comparison. Serial assessments are often necessary as objective signs and symptoms may be delayed. A standardized assessment is paramount in evaluating the athlete with a suspected concussion, but there is no replacement for being familiar with the athlete and using clinical judgment when the athlete seems "not right" despite a "normal" sideline assessment. Ultimately, the clinician should err on the side of caution when making a return-to-play decision.

Sex-Related Differences in Emotion Recognition in Multi-concussed Athletes

OBJECTIVES

Concussion is defined as a complex pathophysiological process affecting the brain. Although the cumulative and long-term effects of multiple concussions are now well documented on cognitive and motor function, little is known about their effects on emotion recognition. Recent studies have suggested that concussion can result in emotional sequelae, particularly in females and multi-concussed athletes. The objective of this study was to investigate sex-related differences in emotion recognition in asymptomatic male and female multi-concussed athletes.

METHODS

We tested 28 control athletes (15 males) and 22 multi-concussed athletes (10 males) more than a year since the last concussion. Participants completed the Post-Concussion Symptom Scale, the Beck Depression Inventory-II, the Beck Anxiety Inventory, a neuropsychological test battery and a morphed emotion recognition task. Pictures of a male face expressing basic emotions (anger, disgust, fear, happiness, sadness, surprise) morphed with another emotion were randomly presented. After each face presentation, participants were asked to indicate the emotion expressed by the face.

RESULTS

Results revealed significant sex by group interactions in accuracy and intensity threshold for negative emotions, together with significant main effects of emotion and group.

CONCLUSIONS

Male concussed athletes were significantly impaired in recognizing negative emotions and needed more emotional intensity to correctly identify these emotions, compared to same-sex controls. In contrast, female concussed athletes performed similarly to same-sex controls. These findings suggest that sex significantly modulates concussion effects on emotional facial expression recognition. (JINS, 2017, 23, 65-77).

An evaluation of Gaelic Athletic Association (GAA) athletes' self-reported practice of playing while concussed, knowledge about and attitudes towards sports-related concussion

BACKGROUND/AIM

Sports-related concussions are now recognized as a major public health concern. However, despite the association of concussion with short- and long-term health consequences, many young athletes still lack basic knowledge about concussion and seem to believe that concussions may be "toughed out" and do not require medical attention. This study assessed self-reported practice of playing in training or a match while concussed among Gaelic Athletic Association (GAA) athletes in Ireland aged 13-25 years old (M=19.19, SD=3.54). This study also assessed knowledge about and attitudes towards sports-related concussion in GAA players in Ireland.

METHODS

Using a self-report questionnaire, data were captured electronically on GAA athletes aged 13-25 years old (n=80) regarding knowledge about the detection, assessment and management of sports-related concussion, as well as participant's attitudes towards concussion and self-reported practice of playing in training or a match while concussed. Data were collected from June to August 2013.

RESULTS

This study revealed that approximately one in four athletes reported having played while concussed in practice or during a match. Males were significantly more likely to play while concussed than females (40.9% and 17.2%, respectively). Results from this study indicated participants lack a complete understanding of concussion, as common misconceptions about concussion prevailed. Analyses revealed that participants generally have safe attitudes towards concussion and concussion management.

CONCLUSION

Generating awareness of the potential short- and long-term health consequences of concussion, coupled with the promotion of safer attitudes towards this injury, could minimize the number of players who return-to-play pre-maturely and promote a more safety-conscious sports culture in Ireland.

Relationship Between Cognitive Assessment and Balance Measures in Adolescents Referred for Vestibular Physical Therapy After Concussion

OBJECTIVE

To examine the relationship between cognitive and balance performance in adolescents with concussion.

DESIGN

Retrospective case series.

SETTING

Tertiary.

PATIENTS

Sixty patients.

INTERVENTIONS

Correlation analyses were performed to describe the relationship between symptoms, cognitive measure, and balance measure at the time of initiation of vestibular physical therapy.

MAIN OUTCOME MEASURES

Cognitive performance was assessed using the Immediate Post-concussion Assessment and Cognitive Testing (ImPACT). The dizziness and balance function measures included dizziness severity rating, Activities-specific Balance Confidence scale (ABC), Dizziness Handicap Inventory (DHI), Functional Gait Assessment, gait speed, Timed "UP and GO," Five Times Sit to Stand, and Sensory Organization Test (SOT). To account for multiple comparisons, the False Discovery Rate method was used.

RESULTS

Performance measures of balance were significantly correlated with cognitive measures. Greater total symptom scores were related to greater impairment in the ABC and DHI (r = 0.35-0.39, P ≤ 0.008) and worse performance in condition 2 of the SOT (r = -0.48, P = 0.004). Among the ImPACT composite scores, lower memory scores were correlated with impaired balance performance measures (r = 0.37-0.59, P ≤ 0.012). Lower visual memory was also correlated with worse ABC scores.

CONCLUSIONS

The significant relationships reported between the cognitive performance scores and balance measures may reflect that similar levels of functioning exist across domains in individuals with protracted recovery who receive vestibular physical therapy.

CLINICAL RELEVANCE

The weak-to-moderate relationships warrant the continuous use of multiple domains of assessment. A better understanding to the relationships between the domains of functioning after concussion may improve the overall management approach for adolescents with concussion.

Characteristics of Pediatric and Adolescent Concussion Clinic Patients With Postconcussion Amnesia

OBJECTIVE

The current study examines the demographics, injury characteristics, and outcomes associated with the presence of postconcussion amnesia in young concussion clinic patients.

DESIGN

Cross-sectional, retrospective clinical cohort.

SETTING

Concussion services clinic.

PATIENTS

Pediatric and adolescent concussion services program patients, presenting within 10 days postinjury, aged 10-18 years, with the goal of returning to sport (n = 245).

ASSESSMENT OF RISK FACTORS

Age, gender, race, head trauma history, injury mechanism, loss of consciousness (LOC), injury-related visit to an emergency department, cognitive and balance scores, symptoms, and management recommendations.

MAIN OUTCOME MEASURES

Univariate and multivariate analyses determined adjusted odds ratios for reported presence of any postconcussion amnesia (anterograde or retrograde).

RESULTS

Factors associated with amnesia (univariate, P < 0.10) and included in the multivariate model were race, head trauma history, mechanism of injury, LOC, injury-related visit to an emergency department, management recommendations and time of injury and initial visit symptom severity. Age and gender were also included in the model due to biological significance. Of the 245 patients, 181 had data for all model variables. Of the 181 patients, 58 reported amnesia. History of head trauma [odds ratio (OR), 2.7; 95% confidence interval (CI), 1.3-5.7]; time of injury (TOI) symptom severity >75th percentile (OR, 2.6; 95% CI, 1.2-5.3) and LOC (OR, 2.2; 95% CI, 1.1-4.6) were found to have significant and independent relationships with amnesia in the multivariate model.

CONCLUSIONS

This study illustrates that patients presenting with postconcussion amnesia are more likely to have a history of head trauma, LOC, and greater symptom severity. Future research is needed to better understand amnesia following concussion.

CLINICAL RELEVANCE

Amnesia presence, previous head trauma, LOC, and increased symptom severity may aid in identifying patients with a greater initial injury burden who warrant closer observation and more conservative management.

Factors associated with delayed recovery in athletes with concussion treated at a pediatric neurology concussion clinic

PURPOSE

With the increase in knowledge and management of sport-related concussion over the last 15 years, there has been a shift from a grading scale approach to an individualized management approach. As a result, there is an increased need to better understand the factors involved in delayed recovery of concussion. The purpose of this retrospective study was to examine factors that may be associated with recovery from sport-related concussion in student athletes aged 11 to 18 years old.

METHODS

Of the 366 patients who met the inclusion criteria, 361 were included in our analysis. The primary dependent variable included days until athlete was able to return to play (RTP). Independent variables of interest included age, gender, academic performance, comorbid factors, sports, on-field markers, days until initial neurological evaluation, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT®) scores, acute headache rescue medications, chronic headache medication, sleep medication, and referral to concussion rehabilitation program.

RESULTS

Variables associated with longer median RTP were being female (35 days), having a referral to concussion rehabilitation program (53 days), being prescribed acute headache rescue therapy (34 days), and having chronic headache treatment (53 days) (all p < 0.05). Variables associated with shorter RTP were on-field marker of headache (23 days) and evaluation within 1 week of concussion by a concussion specialist (16 days) (Both p < 0.05).

CONCLUSION

This study supports the need for a concussed athlete to have access to a provider trained in concussion management in a timely fashion in order to prevent delayed recovery and return to play.

Post-Season Neurophysiological Deficits Assessed by ImPACT and fMRI in Athletes Competing in American Football

Neurocognitive assessment, functional magnetic resonance imaging, and head impact monitoring were used to evaluate neurological changes in high school football players throughout competitive seasons. A substantial number of asymptomatic athletes exhibited neurophysiological changes that persisted post-season, with abnormal measures significantly more common in athletes receiving 50 or more hits per week during the season.

Persisting Effects of Concussion on Heart Rate Variability during Physical Exertion

The purpose of this study was to evaluate cardiac autonomic modulation in university athletes during the post-acute to late phase (mean, 95 days ±63) of injury at rest and during physical exertion. We also sought to evaluate the effect of time since injury and number of injuries on heart rate variability (HRV). We hypothesized that physical exertion would reveal persisting modifications in HRV following a concussion. We included, in a cross-sectional design, athletes who sustained a concussion and matched controls. Concussions were identified by a medical doctor using established criteria. Twelve male concussed and 12 control athletes took part in the study. Control participants were teammates who were chosen to match the concussed athletes with regard to their height, weight, education, and age. The beat-to-beat electrocardiogram intervals of the participants were measured at rest and during physical exertion (isometric hand grip contraction; IHGC), which was sustained for 3 minutes at 30% of the participants' maximum. Linear and nonlinear parameters of HRV were calculated. The ratio between low and high frequency (LF/HF) bands was calculated to assess the sympathovagal balance. During the IHGC, but not at rest, concussed athletes presented significantly lower power in HF bands, leading to a significantly higher LF/HF ratio (p ≤ 0.05). Thus, asymptomatic athletes still may exhibit modifications in cardiac autonomic modulation weeks to months following injury. These modifications may only become apparent during physical exertion. Monitoring HRV may aid diagnosis and provide insight about safe return to play.

Comparison of Neurocognitive Testing and the Measurement of Marinobufagenin in Mild Traumatic Brain Injury: A Preliminary Report

The evaluation of concussed athletes, including testing to determine if and when they may return to play, has become an important task of athletic trainers and team physicians. Currently, concussion protocols are in place, which depend largely upon assessments based upon neurocognitive testing (NCT). The authors have evaluated the use of a biomarker of brain trauma, marinobufagenin (MBG), and compared its application in concussed athletes with the performance of NTC. We found a disparity between these two testing procedures. In this communication, the findings of these comparative data are presented. We noted that athletes whose NCT evaluations had returned to baseline and who were allowed to again participate in play then showed a recurrence of elevated urinary MBG excretion. These observations raise concern as to the processes currently in effect with regard to the decision as to returning athletes to the full activity. They suggest a need for further evaluation.

Benefits of strict rest after acute concussion: a randomized controlled trial

OBJECTIVES

To determine if recommending strict rest improved concussion recovery and outcome after discharge from the pediatric emergency department (ED).

METHODS

Patients aged 11 to 22 years presenting to a pediatric ED within 24 hours of concussion were recruited. Participants underwent neurocognitive, balance, and symptom assessment in the ED and were randomized to strict rest for 5 days versus usual care (1-2 days rest, followed by stepwise return to activity). Patients completed a diary used to record physical and mental activity level, calculate energy exertion, and record daily postconcussive symptoms. Neurocognitive and balance assessments were performed at 3 and 10 days postinjury. Sample size calculations were powered to detect clinically meaningful differences in postconcussive symptom, neurocognitive, and balance scores between treatment groups. Linear mixed modeling was used to detect contributions of group assignment to individual recovery trajectory.

RESULTS

Ninety-nine patients were enrolled; 88 completed all study procedures (45 intervention, 43 control). Postdischarge, both groups reported a 20% decrease in energy exertion and physical activity levels. As expected, the intervention group reported less school and after-school attendance for days 2 to 5 postconcussion (3.8 vs 6.7 hours total, P < .05). There was no clinically significant difference in neurocognitive or balance outcomes. However, the intervention group reported more daily postconcussive symptoms (total symptom score over 10 days, 187.9 vs 131.9, P < .03) and slower symptom resolution.

CONCLUSIONS

Recommending strict rest for adolescents immediately after concussion offered no added benefit over the usual care. Adolescents' symptom reporting was influenced by recommending strict rest.

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.

Diffusion tensor imaging findings and postconcussion symptom reporting six weeks following mild traumatic brain injury

The purpose of this study is to examine the relation between the microstructural architecture of white matter, as measured by diffusion tensor imaging (DTI), and postconcussion symptom reporting 6-8 weeks following mild traumatic brain injury (MTBI). Participants were 108 patients prospectively recruited from a Level 1 Trauma Center (Vancouver, BC, Canada) following an orthopedic injury [i.e., 36 trauma controls (TCs)] or MTBI (n = 72). DTI of the whole brain was undertaken using a Phillips 3T scanner at 6-8 weeks postinjury. Participants also completed a 5 h neurocognitive test battery and a brief battery of self-report measures (e.g., depression, anxiety, and postconcussion symptoms). The MTBI sample was divided into two groups based on ICD-10 criteria for postconcussional syndrome (PCS): first, PCS-present (n = 20) and second, PCS-absent (n = 52). There were no significant differences across the three groups (i.e., TC, PCS-present, and PCS-absent) for any of the neurocognitive measures (p = .138-.810). For the self-report measures, the PCS-present group reported significantly more anxiety and depression symptoms compared with the PCS-absent and TC groups (p < .001, d = 1.63-1.89, very large effect sizes). For the DTI measures, there were no significant differences in fractional anisotropy, axial diffusivity, radial diffusivity, or mean diffusivity when comparing the PCS-present and PCS-absent groups. However, there were significant differences (p < .05) in MD and RD when comparing the PCS-present and TC groups. There were significant differences in white matter between TC subjects and the PCS-present MTBI group, but not the PCS-absent MTBI group. Within the MTBI group, white-matter changes were not a significant predictor of ICD-10 PCS.

Effects of Two Concussions on the Neuropsychological Functioning and Symptom Reporting of High School Athletes

To assess the effects of two sports-related concussions on neuropsychological functioning and symptom reporting, the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) was administered to 483 high school athletes. Three groups of athletes were determined based on the number of previous concussions: no concussion (n = 409), 1 concussion (n = 58), and 2 concussions (n = 16). The results showed that the three groups did not differ in terms of their ImPACT composite scores (Verbal Memory, Visual Memory, Reaction Time, and Processing Speed) and the Total Symptom Score. As there are only a few studies that have reported the sequelae of 2 concussions in high school athletes, it is premature to declare that a repeated concussion does not have persistent neurocognitive effects on high school athletes.

Advanced topics in neuropsychological assessment following sport-related concussion

OBJECTIVE

This study examined seven topics relating to neuropsychological assessment following sport-related concussion: (i) traditional vs. computerized tests; (ii) the value of baseline, pre-season testing; (iii) invalid baseline scores and poor effort; (iv) when to assess following injury; (v) the reliability of neuropsychological tests; (vi) reliable change methodology; and (vii) new methods for identifying cognitive impairment.

MAIN RESULTS

Baseline testing can be helpful for quantifying cognitive deficits following injury and for assessing recovery. At present, however, there is insufficient evidence to conclude that having baseline test results is clearly superior to not having baseline test results. Although invalid baseline test performance can be detected in some athletes, validity indicators cannot determine the extent to which the results were due to deliberately poor performance, confusion or misunderstanding regarding some aspect of the test, distractions in group testing environments or some combination of factors. When interpreting baseline and post-injury data, sophisticated psychometric methods (e.g. reliable change, multivariate base rates) are available to assist with more accurate identification of cognitive impairment and the serial monitoring of recovery.

CONCLUSIONS

The value of neuropsychological assessment in the management of sport-related concussion has a strong empirical foundation. Additional research is needed, however, to refine its use.

Baseline Neurocognitive Performance in Professional Lacrosse Athletes

Background:

Concussions have become a major public health concern for both youth and professional athletes. The long-term consequences of concussion can be debilitating or even life threatening. To reduce these concerns, baseline neurocognitive performance can aid decision making in postconcussion recovery and return to play for athletes sustaining concussions. To date, these data are not available for lacrosse athletes.

Purpose:

To present baseline neurocognitive performance for Major League Lacrosse (MLL) players and to determine differences between athletes with and without a history of concussion.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A retrospective review was conducted of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores from MLL players who completed baseline testing from June 2010 to June 2011. Inclusion required a valid baseline test and no history of concussion in the 3 months prior to testing. Means ± standard deviations were computed for all demographic variables and ImPACT composite scores including visual and verbal memory, reaction time, and visual motor processing speed. Independent-samples t tests were used to determine differences between athletes with and without a history of concussion.

Results:

Valid baseline ImPACT testing was available for 235 MLL athletes (mean age, 25.1 ± 3.0 years). Forty percent of MLL athletes (n = 94) reported a history of concussion, with 14% of those (n = 13) reporting a history of 3 or more previous concussions. There were no differences on any demographic variables between MLL athletes with and without a history of concussion. MLL athletes with a history of concussion had lower ImPACT composite scores than those without a history of concussion, although only the verbal memory composite was found to be statistically significant (MLL with concussion, 83.2 ± 10.8 vs MLL without concussion, 86.9 ± 9.5; P = .007).

Conclusion:

This study establishes baseline ImPACT scores for MLL and demonstrates that athletes with a history of concussion have poorer neurocognitive performance compared with MLL athletes without a history of concussion.

Clinical Relevance:

These data can serve as normative values for subsequent testing following concussion to assess neurocognitive recovery.