Mild traumatic brain injuries in early adolescent rugby players: Long-term neurocognitive and academic outcomes

Traumatic brain injury and long-term associations with work, divorce and academic achievement

OBJECTIVE

Traumatic brain injuries (TBI), irrespective of severity, may have long-term social implications. This study explores the relationships between TBI severity and outcomes related to work stability, divorce, and academic achievement.

METHODS

Using a Danish nationwide sample of persons with and without TBI, we employed case-control and longitudinal cohort designs. The case-control design utilized individuals aged 18 to 60 years and examined work stability. Each case, employed at time of TBI, was compared with 10 matched controls. The cohort design utilized individuals alive from 1980 to 2016 with and without TBI and assessed the likelihood of 1) divorce and 2) higher-level education. TBI exposures included concussion, skull fractures, or confirmed TBI.

RESULTS

TBI cases exhibited higher odds ratios (OR) for work instability at all follow-ups compared to controls. Increased TBI severity was associated with a higher risk of work instability at 2-year follow-up (concussion: OR = 1.83; skull fracture: OR = 2.22; confirmed TBI: OR = 4.55), and with a higher risk of not working at 10-year follow-up (confirmed TBI: OR = 2.82; concussion: OR = 1.63). The divorce incidence rate ratio (IRR) was elevated in individuals with TBI (males: IRR = 1.52; females: IRR = 1.48) compared to those without TBI. Individuals with childhood TBI had reduced chances of attaining high school degree or higher (males: IRR = 0.79; females: IRR = 0.85) compared to those without TBI.

CONCLUSION

TBI is associated with an increased long-term risk of social consequences, including work instability, divorce, and diminished chances of higher education, even in cases with concussion.

Variables associated with days of school missed following concussion: results from the Sport Concussion Outcomes in PEdiatrics (SCOPE) study

OBJECTIVE

To understand factors associated with missed academic time after concussion to improve support for patients. Our goal was to assess patient-specific predictors of total school time lost after pediatric/adolescent concussion.

STUDY DESIGN

We performed a prospective cohort study of children and adolescents (8-18 years of age) seen within 14 days of concussion from seven pediatric medical centers across the United States. We collected outcomes via the Concussion Learning Assessment & School Survey (CLASS) and constructed a multivariable predictive model evaluating patient factors associated with school time loss.

RESULTS

167 patients participated (mean age = 14.5 ± 2.2 years; 46% female). Patients were assessed initially at 5.0 ± 3.0 days post-injury and had a final follow-up assessment 24.5 ± 20.0 days post-concussion. Participants missed a median of 2 days of school (IQR = 0.5-4), and 21% reported their grades dropped after concussion. Higher initial symptom severity rating (β = 0.06, 95% CI = 0.03-0.08, p < 0.001) and perception of grades dropping after concussion (β = 1.37, 95% CI = 0.28-2.45, p = 0.01) were significantly associated with more days of school time missed after concussion. Those who reported their grades dropping reported missing significantly more school (mean = 5.0, SD = 4.7 days missed of school) than those who reported their grades did not drop (mean = 2.2, SD = 2.6 days missed of school; p < 0.001; Cohen's d = 0.87).

CONCLUSIONS

Children and adolescents reported missing a median of 2 days of school following concussion, and more missed school time after a concussion was associated with more severe concussion symptoms and perception of grades dropping. These findings may support recommendations for minimal delays in return-to-learn after concussion.

Sports-Related Concussion Affects Cognitive Function in Adolescents: A Systematic Review and Meta-analysis

BACKGROUND

Rates of sports-related concussion (SRC) are high in adolescents. Ambiguity exists regarding the effect of SRC on cognitive function in adolescents.

PURPOSE

To rigorously examine adolescents' cognitive function after SRC.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

Web of Science, Scopus, and PubMed were searched from database inception until September 2021. Studies were included if participants were adolescents aged 13 to 18 years, if the definition of SRC was fully consistent with the Berlin Consensus Statement on Concussion in Sport, if the study included a control group or in-group baseline test, and if the study reported cognitive outcomes (eg, visual memory, processing speed) that could be separately extracted.

RESULTS

A total of 47 studies were included in the systematic review, of which 31 were included in the meta-analysis, representing 8877 adolescents with SRC. Compared with individuals in the non-SRC group, individuals with SRC had worse performance in cognitive function and reported more symptoms not only in the acute phase but also in the prolonged phase (1-6 months after injury) (visual memory: d = -0.21, 95% CI, -0.37 to -0.05, P = .012; executive function: d = -0.56, 95% CI, -1.07 to -0.06, P = .028; and symptoms: d = 1.17, 95% CI, 0.13 to 2.22, P = .028). Lower scores in most of the outcomes of cognitive function were observed at <3 days and at 3 to 7 days, but higher scores for verbal memory (d = 0.10; 95% CI, 0.03 to 0.17; P = .008) and processing speed (d = 0.17; 95% CI, 0.10 to 0.24; P < .001) were observed at 7 to 14 days after SRC relative to baseline. The effects of SRC on cognitive function decreased over time (100% of the variance in reaction time, P < .001; 99.94% of the variance in verbal memory, P < .001; 99.88% of the variance in visual memory, P < .001; 39.84% of the variance in symptoms, P = .042) in control group studies. Study design, participant sex, measurement tools, and concussion history were found to be modulators of the relationship between cognitive function and SRC.

CONCLUSION

This study revealed that adolescent cognitive function is impaired by SRC even 1 to 6 months after injury. Results of this study point to the need for tools to measure cognitive function with multiple parallel versions that have demographically diversiform norms in adolescents. Effective prevention of SRC, appropriate treatment, and adequate evaluation of cognitive function before return to play are needed in adolescent SRC management. Moreover, caution is warranted when using the baseline-to-postconcussion paradigm in return-to-play decisions.

Association of concussion with high school academic standing: sex, school grade and race as stratifiers

INTRODUCTION

The purpose was to examine the association between concussion history and academic standing among high school students, and whether the association varies by sex, school grade and race/ethnicity.

METHODS

Data from the 2019 Youth Risk Behaviour Survey were used for our cross-sectional study. Exposure was self-reported history of concussions in the past 12 months. Outcome was self-reported academic standing in the past 12 months. Poisson regression was used to analyse the exposure-outcome association, and whether there were differences by our stratifying variables.

RESULTS

Having a history of concussion in the past 12 months was significantly associated with a higher risk of poor academic standing during the same period, and the association varied by race/ethnicity.

DISCUSSION

Youth with a history of concussion may be at risk for poorer academic standing, indicating to the importance of prevention. Future studies are needed to examine the interaction of race/ethnicity on the presented association.

Spinal cord and brain tissue impairments as long-term effects of rugby practice? An exploratory study based on T1 and ihMTsat measures

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Diffuse degeneration of spinal cord (higher T₁) is observed in retired rugby players.

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Demyelination of brain WM tracts (higher T₁ / lower ihMTsat values) is present in rugby players.

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Early aging in both brain and spinal cord tissues may be linked to the rugby practice.

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The aforementioned effects may suggest cumulative effects of long-term impacts on the tissues.

Rugby players are subject to multiple impacts to their head and neck that could have adverse neurological effects and put them at increased risk of neurodegeneration.

Previous studies demonstrated altered default mode network and diffusion metrics on brain, as well as more foraminal stenosis, disc protrusion and neck pain among players of contact sports as compared to healthy controls. However, the long-term effects of practice and repetitive impacts on brain and cervical spinal cord (cSC) of the rugby players have never been systematically investigated.

In this study, 15 retired professional and amateur rugby players (R) and 15 age-matched healthy controls (HC) (all males; mean age R: 46.8 ± 7.6; and HC: 48.6 ± 9.5) were recruited both to investigate cord impairments and further characterize brain structure damage. Medical questionnaires including modified Japanese Orthopedic Association scale (mJOA) and Neck Disability Index (NDI) were filled by all participants. A 3 T multi-parametric MR protocol including conventional qualitative techniques such as T₁-, T₂-, and T₂*-weighted sequences, as well as state-of-the art quantitative techniques including MP2RAGE T₁ mapping and 3D ihMTRAGE, was used on both brain and cSC. Normalized brain WM and GM volumes, spine Overall Stenosis Score, cord cross-sectional area and regional T₁ and ihMT metrics were derived from these acquisitions.

Rugby players showed significantly higher NDI scores, as well as a faster decline of normalized brain GM volume with age as compared to HC. Moreover, higher T₁ values on cSC suggestive of structural degeneration, together with higher T₁ and lower ihMTsat on brain WM suggestive of demyelination, were observed in retired rugby players as compared to age-matched controls, which may suggest cumulative effects of long-term impacts on the tissues. Metrics also suggest early aging and different aging processes on brain tissue in the players.

These preliminary observations provide new insights in the domain, which should now be further investigated on larger cohorts and multicentric longitudinal studies, and further correlated to the likelihood of neurodegenerative diseases and risk factors.

Critical Elements of Return to Learn for Students With Concussion: A Scoping Review

OBJECTIVE

To identify critical elements of return to learn (RTL) for students with concussion and examine the state of the peer-reviewed published literature through a scoping review.

METHODS

Three electronic databases were systematically searched, and reference lists screened for articles addressing components of RTL protocols and accommodations for students with concussion. In total, 100 articles met inclusion criteria, including 56 empirical studies and 44 expert articles.

RESULTS

Four key components to RTL protocols were identified: RTL teams, management approaches, outcome measurement, and accommodations. Both bodies of literature agree on the importance of RTL teams, but evidence for specific monitoring tools and management approaches is less robust. Accommodations have been better addressed by experts than empirical evaluation. Empirical studies are largely cross-sectional, and many are survey based. Just 24 include student perspectives. Publication of expert literature has declined in frequency, as empirical studies have become more common.

CONCLUSION

This scoping review describes the current landscape of RTL and provides guidance toward expanding the empirical literature to systematically determine best practices to serve students with concussion.

Concussion History and Balance Performance in Adolescent Rugby Union Players

BACKGROUND

Sports-related concussion is a worldwide problem. There is a concern that an initial concussion can cause prolonged subclinical disturbances to sensorimotor function that increase the risk of subsequent injury. The primary aim of this study was to examine whether a history of sports-related concussion has effects on static and dynamic balance performance in adolescent rugby players.

HYPOTHESIS

Dynamic balance would be worse in players with a history of concussion compared with those with no history of concussion.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Male adolescent rugby players aged 14 to 18 years from 5 schools were recruited before the start of the 2018-2019 playing season. Participants completed questionnaires and physical tests, including dynamic Y balance and single-leg static balance (eyes closed) tests, while performing single and dual tasks. Dynamic balance was assessed using inertial sensor instrumentation. Dependent variables were normalized reach distance and the sample entropy (SEn) of the 3 axes (x, y, and z).

RESULTS

Of the 195 participants, 100 reported a history of concussion. Those with a history of concussion demonstrated higher SEn in all directions, with highest values during anterior (standardized mean difference [SMD], 0.4; 95% CI, 0.0-0.7; P = .027) and posteromedial (SMD, 0.5; 95% CI, 0.2-0.9; P = .004) reach directions compared with those with no history. There was no difference between groups (concussion history vs control) in traditional Y balance reach distances in the anterior or posteromedial directions or single-leg static balance during both single- (P = .47) and dual-task (P = .67) conditions.

CONCLUSION

Adolescent rugby union athletes with a history of concussion had poorer dynamic balance during performance tasks compared with healthy controls. Static single-leg balance tests, either single or dual task, may not be sensitive enough to detect sensorimotor deficits in those with a history of concussion.

A Systematic Review of Cognitive Functioning After Traumatic Brain Injury in Individuals Aged 10-30 Years

Given the importance of the period of life from 10 to 30 years in terms of cognitive development and education, combined with the high incidence of traumatic brain injury (TBI) during this period, and limited consensus as to the pattern and degree of cognitive impairment post TBI during this period, we conducted a systematic review to investigate cognitive performance across a range of domains among individuals between the ages of 10 and 30 years who had sustained a TBI. We searched five databases and identified 799 unique records; 52 met our inclusion criteria. These studies reported cognitive function for intelligence, attention, memory, processing speed, and executive function. The majority of the studies reported significant effects, suggesting that TBI is associated with cognitive impairments in these domains. Nine of the studies used physiological tests (EEG and fMRI), the outcomes of which supported behaviorally demonstrated cognitive deficits. In the studies we reviewed, individuals aged 10-30 years who had experienced a TBI performed worse than healthy controls on cognitive function measures-specifically for attention, memory, processing speed, and executive function. In the studies that subjected the individuals with TBI to EEG and fMRI, atypical activation in associated brain regions was demonstrated while the individuals were undergoing cognitive tasks. However, caution should be taken when interpreting the overall results due to the high risk of bias across the majority of the studies. The broader implications of reduced cognitive performance after TBI across this age range are yet to be fully understood.

The relationships between rugby union, and health and well-being: a scoping review

OBJECTIVE

To scope the relationships between rugby union, and health and well-being.

DESIGN

Scoping review.

DATA SOURCES

Published and unpublished reports of any age, identified by searching electronic databases, platforms and reference lists.

METHODS

A three-step search strategy identified relevant published primary, secondary studies and grey literature, which were screened using a priori inclusion criteria. Data were extracted using a standardised tool, to form (1) a numerical analysis and (2) a thematic summary.

RESULTS AND DISCUSSION

6658 records were identified, and 198 studies met the inclusion criteria. All forms of rugby union can provide health-enhancing physical activity (PA). 'Non-contact' and wheelchair rugby in particular provide a wide range of physical and mental health and well-being benefits. The evidence is either mixed or unclear in relation to 'contact' rugby union and its effects on a range of physical health domains. Injury and concussion incidence rates are high for contact rugby union relative to other sports.

CONCLUSIONS

A wide range of stakeholders as well as existing and potential participants can use this information to make a more informed decision about participating in and promoting rugby union as a health-enhancing activity. Industry and policy-makers can use this review to inform policies and strategies that look to increase participation rates and use rugby union as a vehicle to contribute positively to population health. Further research understanding rugby union's contribution to PA as well as to muscle-strengthening and balance is indicated, as well as research examining more health and well-being outcomes across more diverse cohorts.

Academic Performance Following Sport-Related Concussions in Children and Adolescents: A Scoping Review

Sport-related concussions (SRC) are an increasingly common concern in young athletes, with long-term cognitive, physiological, behavioral, and psychological adverse outcomes. An estimated 1.1 million to 1.9 million SRCs occur per year in children <18 years old in the United States. The post-concussive state has demonstrated consequences in several domains, including athletics and academics, although much more research has been conducted on the former. The objective of this scoping review was to ascertain findings from published studies on the effects of SRCs on academic performance and quality of life of young student athletes. A total of 175 articles were screened within the PubMed and CINAHL databases, along with a Google search. Fourteen papers fulfilled the inclusion criteria and were analyzed in the review. Quantitative and qualitative data were collated and demonstrated the heterogeneity with which, post-concussion academic performance outcomes were measured; only 4 of the 14 studies utilized formal academic metrics such as changes in grade point average (GPA) or examination scores. While the results overall did show statistically significant implications on academic performance decline after SRC, it is clear that there remains a paucity of research determining the consequences of SRCs on academic performance in the school environment. Further research is needed to better understand how to implement accommodations in the student’s learning environment and guide return-to-learn protocols for student athletes following SRC.

Comparison of head impact measurements via an instrumented mouthguard and an anthropometric testing device

The purpose of this study was to determine and compare the efficacy of head impact measurements via an electronic sensor framework, embedded within a mouthguard, against an anthropometric testing device. Development of the former is in response to the growing issue of head impacts and concussion in rugby union. Testing was conducted in a vehicle safety laboratory using a standard impact protocol utilising the headforms of anthropometric testing devices. The headforms were subjected to controlled front and side impacts. For each impact, the linear acceleration and rotational velocity was measured over a 104-ms interval at a frequency of 1 kHz. The magnitude of peak linear acceleration and peak rotational velocity was determined from the measured time-series traces and statistically compared. The peak linear acceleration and rotational velocity had intraclass correlation coefficients of 0.95 and 0.99, respectively. The root-mean-square error between the measurement systems was 4.3 g with a standard deviation of 3.5 g for peak linear acceleration and 0.7 rad/s with a standard deviation of 0.4 rad/s for rotational velocity. Bland and Altman analysis indicated a systematic bias of 2.5 g and − 0.5 rad/s and limits of agreement (1.96 × standard deviation) of ± 13.1 g and ± 1.25 rad/s for the instrumented mouthguard. These results provide the basis on which the instrumented mouthguard can be further developed for deployment and application within professional rugby, with a view to accurately and reliably quantify head collision dynamics.

What they know and who they are telling: Concussion knowledge and disclosure behaviour in New Zealand adolescent rugby union players

The purpose of this study was to survey high school rugby players from a range of ethnic, geographic and socioeconomic backgrounds in New Zealand (NZ) to gain an understanding of concussion knowledge, awareness of NZ Rugby's (NZR) guidelines and attitudes towards reporting behaviours. Male and female high school rugby players (n= 416) from across NZ were surveyed. The findings indicated that 69% of players had sustained a suspected concussion, and 31% had received a medical diagnosis of concussion. 63% of players indicated they were aware of NZR's guidelines. Māori and Pasifika players were less likely to be aware of the guidelines compared to NZ European, Adjusted OR 0.5, p = 0.03. Guideline awareness was significantly higher for those from high decile schools when compared to low (Unadjusted OR 1.63, p = 0.04); however, when ethnicity and school locations were controlled for this became non-significant (Adjusted OR= 1.3, p=0.37). The coach was the key individual for the provision of concussion information and disclosure of symptoms for players. The findings of this study will inform the development and delivery of NZR's community concussion initiative and how these examined factors influence a high school player's concussion knowledge and reporting behaviour.

Discovering Oculometric Patterns to Detect Cognitive Performance Changes in Healthy Youth Football Athletes

In this paper, we focus on the application of oculometric patterns extracted from raw eye movements during a mental workload task to assess changes in cognitive performance in healthy youth athletes over the course of a typical sport season. Oculometric features pertaining to fixations and saccades were measured on 116 athletes in pre- and post-season testing. Participants were between 7 and 14 years of age at pre-season testing. Due to varied developmental rates, there were large interindividual performance differences during a mental workload task consisting of reading numbers. Based on different reading speeds, we classified three profiles (slow, moderate, and fast) and established their corresponding baselines for oculometric data. Within each profile, we describe changes in oculomotor function based on changes in cognitive performance during the season. To visualize these changes in multidimensional oculometric data, we also present a multidimensional visualization tool named DiViTo (diagnostic visualization tool). These experimental, computational informatics and visualization methodologies may serve to utilize oculometric information to detect changes in cognitive performance due to mild or severe cognitive impairment such as concussion/mild traumatic brain injury, as well as possibly other disorders such as attention deficit hyperactivity disorders, learning/reading disabilities, impairment of alertness, and neurocognitive function.

Traumatic Brain Injury Temporal Proteome Guides KCC2-Targeted Therapy

Advancing therapeutics for traumatic brain injury (TBI) remains a challenge, necessitating testable targets with interventions appropriately timed to intercede on evolving secondary insults. Neuroproteomics provides a global molecular approach to deduce the complex post-translational processes that underlie secondary events after TBI. Yet method advancement has outpaced approaches to interrogate neuroproteomic complexity, in particular when addressing the well-recognized temporal evolution of TBI pathobiology. Presented is a detailed account of the temporal neuroproteomic response to mild-moderate rat controlled cortical impact within perilesioned somatosensory neocortex across the first two weeks after injury. Further, this investigation assessed use of artificial neural network and functional enrichment analyses to discretize the temporal response across some 2047 significantly impacted proteins. Results were efficiently narrowed onto ion transporters with phenotypic relevance to abnormal GABAergic transmission and a delayed decline amenable to intervention under managed care conditions. The prototypical target potassium/chloride co-transporter 2 (KCC2 or SLC12A5) was investigated further with the KCC2-selective modulator CLP290. Guided by post-translational processing revealed one-day after insult to precede KCC2 protein loss a day after, CLP290 was highly effective at restoring up to 70% of lost KCC2 localization, which was significantly correlated with recovery of sham-level function in assessed somatosensory behavioral tasks. The timing of administration was important, with no significant improvement observed if given earlier, one-hour after insult, or later when KCC2 protein decline begins. Results portend importance for a detailed post-translational characterization when devising TBI treatments, and support the therapeutic promise of KCC2-targeted CLP290 intervention for positive functional recovery after brain injury.

Five-Year Trends in Marital Stability, Academic Achievement, and Socioeconomic Indicators After Concussion: A National Register Study

OBJECTIVE

To examine long-term trends in marital stability, academic achievement, income, and socioeconomic status in patients with concussion.

DESIGN AND SETTING

Danish national register-based cohort study with 5 years of follow-up.

PARTICIPANTS

A total of 23 549 hospital-admitted or emergency-treated patients between 18 and 60 years of age with concussion (International Classification of Diseases, Tenth Revision [ICD-10] diagnosis S06.0) and 22 228 matching controls.

MAIN MEASURES

Outcomes were the differences between patients with concussion and controls in the change from injury date to 5 years postinjury in the dichotomized outcomes-martial stability, academic achievement, income, and socioeconomic status.

RESULTS

Fewer patients had high education (19.43%) compared with controls (23.96%) and the adjusted odds ratio (OR) of high education beyond the difference in prevalence at baseline became even lower at 5 years of follow-up (OR: 0.93, 95% confidence interval [CI]: 0.90-0.95). Patients were to a lesser extent gainfully employed (67.05%) compared with controls (77.32%) and had lower odds of being gainfully employed (OR: 0.83, 95% CI: 0.79-0.88), self-employed, leaders, or managers (OR: 0.89, 95% CI: 0.84-0.95) at 5 years postinjury, beyond differences at baseline.

CONCLUSIONS

Academic achievement and socioeconomic status are affected by concussion. There is no evidence that marital stability and income are affected. Supporting interventions should be considered those at risk of persistent symptoms.

The Montreal Cognitive Assessment as a Cognitive Screening Tool in Athletes

Background: The Montreal Cognitive Assessment (MoCA) is a cognitive screening tool known to accurately measure mild cognitive impairment (MCI) in many different neurological populations. Objective: We aimed to determine whether a sport-related concussion (SRC) history and other concussion modifiers influence global cognitive function in high-performance athletes. Methods: A cross-sectional study of 326 varsity and national team athletes aged 18–36 years was completed at the University of Calgary Sports Medicine Clinic, Calgary, Alberta, Canada. Logistic regression analysis was used to examine the association between the total MoCA score, MoCA subscales, and number of previous SRC, adjusting for age, sex, sport participation (SP), and concussion modifiers. Results: Athletes with a history of three or more SRC were 5.36 times more likely to score less than 26/30 on the MoCA (the cutoff for MCI) compared to athletes with two or less SRC (p = 0.02). Males were 2.23 times more likely to have MCI than females (p = 0.0004). There was a significant relationship between the number of previous concussions and the MoCA subscales of attention (p = 0.05) and abstraction (p = 0.003). Age, SP, and concussion modifiers (migraine, depression, anxiety, and attention deficit and hyperactivity disorder) did not influence the relationship between MoCA and previous concussion history. Conclusion: In the appropriate clinical context, cognitive screening with the MoCA may benefit clinical care in athletes with multiple previous SRC, but should not replace a full neuropsychological assessment. Thus, further research is needed to compare the MoCA to full neuropsychological assessments in this population.

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.

Signs of cognitive dysfunction in adult players of club level rugby

The objective of this study was to investigate players of club level Rugby Union (hereafter rugby) over one rugby season, for signs of residual cognitive dysfunction due to repeated concussive events incurred during long-term participation in the sport. Adult male players of club level rugby, without a diagnosis of a concussion during the season ( n = 20), were compared with non-contact club level sports participants ( n = 22) of equivalent sex, age, education, and estimated IQ at pre-, mid-, and post-season intervals. Measures included the ImPACT Verbal Memory, Visual Memory, Visual Motor Speed and Reaction Time composites, and the Purdue Pegboard test. Statistical group comparisons revealed consistently poorer performance for rugby players compared with controls for ImPACT Visual Motor Speed and Reaction Time composites at all test intervals, and for the Purdue Pegboard tasks at the first two test intervals. Repeat measures comparisons across the three test intervals demonstrated differential learning patterns between groups on ImPACT Visual Memory, ImPACT Reaction Time, and Purdue Both tasks, suggestive of cognitive vulnerability in the rugby group. Overall, the results reveal deleterious cognitive performance in adult club level rugby players relative to equivalent non-contact sports controls. The finding serves to endorse indications from other studies that demonstrate persistent brain injury effects in association with long-term participation in a contact sport. Recommendations for further research and management of concussion in rugby players are discussed.

Concussion History and Cognitive Function in a Large Cohort of Adolescent Athletes

BACKGROUND

The incidence of reported concussions in the adolescent population is increasing, yet research on the effects of concussions in this population is minimal and inconclusive.

PURPOSE

To assess the association between concussion and performance on a cognitive test battery.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Using multivariate models, the authors assessed the association between concussion and performance on a cognitive test battery among 5616 high school and junior high school athletes. The researchers utilized a global cognitive score and scores for 5 domains: verbal memory, visual memory, visual motor, reaction time, and impulse control. Each cognitive score was converted to a z score with the mean and SD of the nonconcussed population. Results from each model were then interpreted as change in the standardized unit score. In the models, concussion was evaluated as ever having a concussion, number of concussions, time since last concussion, and age at first concussion.

RESULTS

Ever having a concussion was associated with a mean decrease of 0.11 standardized units (95% CI, -0.20 to -0.01) on the global cognitive score and lower scores in all cognitive domains. Each additional concussion was associated with lower scores on global cognitive function (effect estimate, -0.06; 95% CI, -0.11 to -0.02), verbal memory, visual memory, and impulse control. Concussion in early childhood was associated with lower global cognition (effect estimate, -0.05; 95% CI, -0.08 to -0.01), visual memory, and motor visual scores as compared with concussions in later childhood. The associations between time since last concussion and cognitive test scores were nonlinear, and on all tests, lower scores were observed even ≥1 year after the concussion.

CONCLUSION

On the basis of objective performance metrics for cognitive function, concussions had a more persistent effect on cognitive function than previously thought. The age at which an individual has his or her first concussion may be an important factor in determining long-lasting cognitive effects.

A Comparison of Cognitive Function in Former Rugby Union Players Compared with Former Non-Contact-Sport Players and the Impact of Concussion History

AIM

This study investigated differences in cognitive function between former rugby and non-contact-sport players, and assessed the association between concussion history and cognitive function.

METHODS

Overall, 366 former players (mean ± standard deviation [SD] age 43.3 ± 8.2 years) were recruited from October 2012 to April 2014. Engagement in sport, general health, sports injuries and concussion history, and demographic information were obtained from an online self-report questionnaire. Cognitive functioning was assessed using the online CNS Vital Signs neuropsychological test battery. Cohen's d effect size statistics were calculated for comparisons across player groups, concussion groups (one or more self-reported concussions versus no concussions) and between those groups with CNS Vital Signs age-matched norms (US norms). Individual differences within groups were represented as SDs.

RESULTS

The elite-rugby group (n = 103) performed worse on tests of complex attention, processing speed, executive functioning, and cognitive flexibility than the non-contact-sport group (n = 65), and worse than the community-rugby group (n = 193) on complex attention. The community-rugby group performed worse than the non-contact group on executive functioning and cognitive flexibility. Compared with US norms, all three former player groups performed worse on verbal memory and reaction time; rugby groups performed worse on processing speed, cognitive flexibility and executive functioning; and the community-rugby group performed worse on composite memory. The community-rugby group and non-contact-sport group performed slightly better than US norms on complex attention, as did the elite-rugby group for motor speed. All three player groups had greater individual differences than US norms on composite memory, verbal memory and reaction time. The elite-rugby group had greater individual differences on processing speed and complex attention, and the community-rugby group had greater individual differences on psychomotor speed and motor speed. The average number of concussions recalled per player was greater for elite rugby and community rugby than non-contact sport. Former players who recalled one or more concussions (elite rugby, 85 %; community rugby, 77 %; non-contact sport, 23 %) had worse scores on cognitive flexibility, executive functioning, and complex attention than players who did not recall experiencing a concussion.

CONCLUSIONS

Past participation in rugby or a history of concussion were associated with small to moderate neurocognitive deficits (as indicated by worse CNS Vital Signs scores) in athletes post retirement from competitive sport.

Influence of playing rugby on long-term brain health following retirement: a systematic review and narrative synthesis

Objectives

The aim of this review was to systematically investigate long-term brain health in retired rugby players.

Methods

Six databases were systematically searched from inception to January 2018 using Medical Subject Headings and keywords. Two reviewers independently screened studies for inclusion. Cross-sectional studies of living retired male or female rugby players in which at least one cognitive test was used as an outcome measure were included. Data extraction was performed using Strengthening the Reporting of Observational Studies in Epidemiology guidelines. Methodological quality was assessed independently by two reviewers using the Downs and Black methodological quality tool.

Results

This review yielded six studies with an overall methodological quality of 'moderate'. A total of 672 male retired rugby players (mean ages of 38-52 years) were included in this review. Three studies investigated neuropsychological functioning in retired rugby players in comparison with controls, with no significant evidence of decreased performance in the majority of tests when compared with controls. Five out of the six studies explored self-reported measures of cognition. Three studies compared retired rugby players to controls, one of which found significantly increased subjective cognitive complaints among retired rugby players. The other two studies found that persistent postconcussion symptoms were associated with a higher number of self-reported concussions. Two studies reported decreased fine motor control in retired rugby players in comparison with controls. Neurometabolites and electrophysiological changes were explored by two studies, with minimal and non-significant findings.

Conclusions

Overall findings are mixed. Methodological biases reduce the overall study quality and limited the conclusions that can be drawn. Findings of decreased fine motor control in retired athletes may be influenced by lack of controlling for evidence of upper limb musculoskeletal injuries. While some studies show evidence of reduced cognitive function among former athletes, the results are not significantly lower than population norms. Cognitive findings from this review are inconsistent within and across study cohorts and are biased towards positive findings when self-report methods were selected. Current evidence suggests that large gaps remain in the understanding of the cause-and-effect relationships between playing rugby and long-term brain health in retired players.

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.

Risks associated with significant head impact events in elite rugby union

PRIMARY OBJECTIVES

To conduct video and statistical analysis on Rugby Union play, focusing mainly on the tackle, to establish the player to player configurations for significant direct head impacts and non-direct head impacts.

RESEARCH DESIGN

Quantitative, observational cohort study.

METHODS AND PROCEDURES

Video analysis of 52 significant direct head impacts (31 Tackle, 10 Ruck, 7 Dive and 4 Ground) and 40 non-direct head impact tackles from 2014/15 International Rugby Union matches. Relative risk, 95% CI and p-values were calculated for a range of tackle variables.

MAIN OUTCOME AND RESULTS

Upper body tackles and lower body tackles accounted for 37% (19) and 23% (12) of cases, respectively, with the tackler as the head impacted player for 97% (30) of cases. The majority (81%) of tackle-related significant direct head impacts occurred in the second half of the game, with 63% of upper body tackle significant direct head impacts occurring in the final quarter. Tackler head placement and high speed tackles had statistical significance for causing tackle related significant direct head impacts as well as foot planting and difference in tackler and ball carrier mass for upper body tackles and ball carrier change in direction for lower body tackles.

CONCLUSION

Tackle variables that statistically increased the risk of significant direct head impact were identified, which can aid player protection strategies.

Accuracy of Self-report as a Method of Screening for Lifetime Occurrence of Traumatic Brain Injury Events that Resulted in Hospitalization

BACKGROUND

Traumatic brain injury (TBI) occurs frequently during child and early adulthood, and is associated with negative outcomes including increased risk of drug abuse, mental health disorders and criminal offending. Identification of previous TBI for at-risk populations in clinical settings often relies on self-report, despite little information regarding self-report accuracy. This study examines the accuracy of adult self-report of hospitalized TBI events and the factors that enhance recall.

METHODS

The Christchurch Health and Development Study is a birth cohort of 1265 children born in Christchurch, New Zealand, in 1977. A history of TBI events was prospectively gathered at each follow-up (yearly intervals 0-16, 18, 21, 25 years) using parental/self-report, verified using hospital records.

RESULTS

At 25 years, 1003 cohort members were available, with 59/101 of all hospitalized TBI events being recalled. Recall varied depending on the age at injury and injury severity, with 10/11 of moderate/severe TBI being recalled. Logistic regression analysis indicated that a model using recorded loss of consciousness, age at injury, and injury severity, could accurately classify whether or not TBI would be reported in over 74% of cases.

CONCLUSIONS

This research demonstrates that, even when individuals are carefully cued, many instances of TBI will not recalled in adulthood despite the injury having required a period of hospitalization. Therefore, screening for TBI may require a combination of self-report and review of hospital files to ensure that all cases are identified. (JINS, 2016, 22, 717-723).

RISUS study: Rugby Injury Surveillance in Ulster Schools

OBJECTIVE

To examine injury patterns in adolescent rugby players and determine factors associated with injury risk.

DESIGN

Prospective injury surveillance study.

SETTING

N=28 Grammar Schools in Ulster, Ireland (2014-2015 playing season).

PARTICIPANTS

825 adolescent rugby players, across in 28 school first XV rugby squads; mean age 16.9 years.

MAIN OUTCOME MEASURES

Injuries were classified by body part and diagnosis, and injury incidence using injuries per 1000 match hours of exposure. HRs for injury were calculated through Cox proportional hazard regression after correction for influential covariates.

RESULTS

A total of n=426 injuries were reported across the playing season. Over 50% of injuries occurred in the tackle situation or during collisions (270/426), with few reported during set plays. The 3 most common injury sites were head/face (n=102, 23.9%), clavicle/shoulder (n=65, 15.3%) and the knee (n=56, 13.1%). Sprain (n=133, 31.2%), concussion (n=81, 19%) and muscle injury (n=65, 15.3%) were the most common diagnoses. Injury incidence is calculated at 29.06 injuries per 1000 match hours. There were no catastrophic injuries. A large percentage of injuries (208/424) resulted in absence from play for more than 28 days. Concussion carried the most significant time out from play (n=33; 15.9%), followed by dislocations of the shoulder (n=22; 10.6%), knee sprains (n=19, 9.1%), ankle sprains (n=14, 6.7%), hand/finger/thumb (n=11; 5.3%). 36.8% of participants in the study (304/825) suffered at least one injury during the playing season. Multivariate models found higher risk of injury (adjusted HR (AHR); 95% CI) with: higher age (AHR 1.45; 1.14 to 1.83), heavier weight (AHR 1.32; 1.04 to 1.69), playing representative rugby (AHR 1.42; 1.06 to 1.90) and undertaking regular strength training (AHR 1.65; 1.11 to 2.46). Playing for a lower ranked team (AHR 0.67; 0.49 to 0.90) and wearing a mouthguard (AHR 0.70; 0.54 to 0.92) were associated with lower risk of injury.

CONCLUSIONS

There was a high incidence of severe injuries, with concussion, ankle and knee ligament injuries and upper limb fractures/dislocations causing greatest time loss. Players were compliant with current graduated return-to-play regulations following concussion. Physical stature and levels of competition were important risk factors and there was limited evidence for protective equipment.