Sports-related concussions: diagnosis, complications, and current management strategies

Sport-related concussion knowledge and attitudes of staff working in English elite women's football: a survey-based study

BACKGROUND

Sport-related concussion (SRC) remains an injury of concern in sport, including football(soccer). There has been little investigation into SRC knowledge and attitudes of support staff working in the professional setting.

METHODS

An amended version of the Rosenbaum Concussion Knowledge and Attitudes Survey(RoCKAS) was distributed online to coaching staff, and medical and performance staff, working at clubs in the English Football Association Women's SuperLeague (WSL) and Championship. Completion of the survey generated two scores: concussion knowledge index (CKI) and concussion attitudes index (CAI).

RESULTS

Sixty-three completed surveys were returned. Eighteen respondents were coaching staff, and 45 were medical and performance staff. The median CKI in medical and performance staff was significantly greater than in coaching staff. There was no significant difference in CAIbetween coaching staff and medical and performance staff. There was no correlation between CKI and CAI across all staff.

CONCLUSION

Medical and performance staff working in elite women's football have greater knowledge of SRC than coaching staff. However, this does not always translate into safe behaviours on the field. Education should continue to be mandated across the professional game amongst support staff in order to maximise player welfare and enhance injury outcomes, whilst also reinforcing present SRC guidance.

Osteopathic manipulative treatment for concussions and postconcussive syndrome in athletes: a literature review

CONTEXT

Concussions are the most common type of traumatic brain injury (TBI) and can often occur in athletes. These injuries have many deleterious acute symptoms and can lead to the development of postconcussive syndrome (PCS). Osteopathic manipulative treatment (OMT) is a treatment option that may benefit patients with concussions and PCS.

OBJECTIVES

The objective of this review is to determine whether OMT can improve symptoms associated with concussions and PCS in athletes.

METHODS

A comprehensive literature review was conducted between August 2021 and March 2022 by two authors (Z.K.L. and K.D.T.) who searched the literature utilizing PubMed, Google Scholar, and Cochrane Library. Articles reviewed included case reports, case studies, randomized control trials, meta-analyses, and peer-reviewed journal articles. Search terms included concussion, postconcussive symptoms, osteopathic manipulative medicine, and manipulation. To be included into this study, articles must have included OMT from an osteopathic physician or manipulative techniques by nonosteopathic providers for patients with a concussion or PCS, and the insulting injury must have occurred in an athletic setting. No disagreements occurred between authors about what studies to include. However, we were prepared to come to a unanimous decision through discussion among the authors. A narrative synthesis was performed. No other data analyses were conducted in this study.

RESULTS

Included in this review were nine articles including randomized control trials, retrospective review, case series, longitudinal, retrospective studies, and case reports. The literature shows the positive effects of OMT and manipulative techniques on symptom resolution after a concussion. However, most of the literature is qualitative rather than quantitative in nature, lacking in randomized control trials.

CONCLUSIONS

There is a scarcity of high-quality studies evaluating the effectiveness of OMT on concussions and PCS. More research is needed to understand the degree of benefit for this treatment option.

Loss of Consciousness and Righting Reflex Following Traumatic Brain Injury: Predictors of Post-Injury Symptom Development (A Narrative Review)

Identifying predictors for individuals vulnerable to the adverse effects of traumatic brain injury (TBI) remains an ongoing research pursuit. This is especially important for patients with mild TBI (mTBI), whose condition is often overlooked. TBI severity in humans is determined by several criteria, including the duration of loss of consciousness (LOC): LOC < 30 min for mTBI and LOC > 30 min for moderate-to-severe TBI. However, in experimental TBI models, there is no standard guideline for assessing the severity of TBI. One commonly used metric is the loss of righting reflex (LRR), a rodent analogue of LOC. However, LRR is highly variable across studies and rodents, making strict numeric cutoffs difficult to define. Instead, LRR may best be used as predictor of symptom development and severity. This review summarizes the current knowledge on the associations between LOC and outcomes after mTBI in humans and between LRR and outcomes after experimental TBI in rodents. In clinical literature, LOC following mTBI is associated with various adverse outcome measures, such as cognitive and memory deficits; psychiatric disorders; physical symptoms; and brain abnormalities associated with the aforementioned impairments. In preclinical studies, longer LRR following TBI is associated with greater motor and sensorimotor impairments; cognitive and memory impairments; peripheral and neuropathology; and physiologic abnormalities. Because of the similarities in associations, LRR in experimental TBI models may serve as a useful proxy for LOC to contribute to the ongoing development of evidence-based personalized treatment strategies for patients sustaining head trauma. Analysis of highly symptomatic rodents may shed light on the biological underpinnings of symptom development after rodent TBI, which may translate to therapeutic targets for mTBI in humans.

Numerical Simulation of Concussive-Generated Cortical Spreading Depolarization to Optimize DC-EEG Electrode Spacing for Noninvasive Visual Detection

BACKGROUND

Cortical spreading depolarization (SD) is a propagating depolarization wave of neurons and glial cells in the cerebral gray matter. SD occurs in all forms of severe acute brain injury, as documented by using invasive detection methods. Based on many experimental studies of mechanical brain deformation and concussion, the occurrence of SDs in human concussion has often been hypothesized. However, this hypothesis cannot be confirmed in humans, as SDs can only be detected with invasive detection methods that would require either a craniotomy or a burr hole to be performed on athletes. Typical electroencephalography electrodes, placed on the scalp, can help detect the possible presence of SD but have not been able to accurately and reliably identify SDs.

METHODS

To explore the possibility of a noninvasive method to resolve this hurdle, we developed a finite element numerical model that simulates scalp voltage changes that are induced by a brain surface SD. We then compared our simulation results with retrospectively evaluated data in patients with aneurysmal subarachnoid hemorrhage from Drenckhahn et al. (Brain 135:853, 2012).

RESULTS

The ratio of peak scalp to simulated peak cortical voltage, Vscalp/Vcortex, was 0.0735, whereas the ratio from the retrospectively evaluated data was 0.0316 (0.0221, 0.0527) (median [1st quartile, 3rd quartile], n = 161, p < 0.001, one sample Wilcoxon signed-rank test). These differing values provide validation because their differences can be attributed to differences in shape between concussive SDs and aneurysmal subarachnoid hemorrhage SDs, as well as the inherent limitations in human study voltage measurements. This simulated scalp surface potential was used to design a virtual scalp detection array. Error analysis and visual reconstruction showed that 1 cm is the optimal electrode spacing to visually identify the propagating scalp voltage from a cortical SD. Electrode spacings of 2 cm and above produce distorted images and high errors in the reconstructed image.

CONCLUSIONS

Our analysis suggests that concussive (and other) SDs can be detected from the scalp, which could confirm SD occurrence in human concussion, provide concussion diagnosis on the basis of an underlying physiological mechanism, and lead to noninvasive SD detection in the setting of severe acute brain injury.

Overview of Traumatic Brain Injury in American Football Athletes

OBJECTIVE

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

DATA SOURCES

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

RESULTS

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

CONCLUSION

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

The Novel Monoacylglycerol Lipase Inhibitor MJN110 Suppresses Neuroinflammation, Normalizes Synaptic Composition and Improves Behavioral Performance in the Repetitive Traumatic Brain Injury Mouse Model

Modulation of the endocannabinoid system has emerged as an effective approach for the treatment of many neurodegenerative and neuropsychological diseases. However, the underlying mechanisms are still uncertain. Using a repetitive mild traumatic brain injury (mTBI) mouse model, we found that there was an impairment in locomotor function and working memory within two weeks post-injury, and that treatment with MJN110, a novel inhibitor of the principal 2-arachidononyl glycerol (2-AG) hydrolytic enzyme monoacylglycerol lipase dose-dependently ameliorated those behavioral changes. Spatial learning and memory deficits examined by Morris water maze between three and four weeks post-TBI were also reversed in the drug treated animals. Administration of MJN110 selectively elevated the levels of 2-AG and reduced the production of arachidonic acid (AA) and prostaglandin E₂ (PGE₂) in the TBI mouse brain. The increased production of proinflammatory cytokines, accumulation of astrocytes and microglia in the TBI mouse ipsilateral cerebral cortex and hippocampus were significantly reduced by MJN110 treatment. Neuronal cell death was also attenuated in the drug treated animals. MJN110 treatment normalized the expression of the NMDA receptor subunits NR2A and NR2B, the AMPA receptor subunits GluR1 and GluR2, and the GABA_A receptor subunits α1, β2,3 and γ2, which were all reduced at 1, 2 and 4 weeks post-injury. The reduced inflammatory response and restored glutamate and GABA receptor expression likely contribute to the improved motor function, learning and memory in the MJN110 treated animals. The therapeutic effects of MJN110 were partially mediated by activation of CB1 and CB2 cannabinoid receptors and were eliminated when it was co-administered with DO34, a novel inhibitor of the 2-AG biosynthetic enzymes. Our results suggest that augmentation of the endogenous levels of 2-AG can be therapeutically useful in the treatment of TBI by suppressing neuroinflammation and maintaining the balance between excitatory and inhibitory neurotransmission.

Incidence of Injuries, Illness and Related Risk Factors in Cross-Country Marathon Mountain Biking Events: A Systematic Search and Review

Background

Cycling is a popular global sport and method of transportation and a significant contributor to admissions to hospital emergency units following an injury. Mountain biking events present additional challenges with remote venues and isolated courses, for which on-site medical care is often provided, for both injury and illness occurring during races. National health data may not represent these unique events, and specific data on incidence of injury and illness in mountain biking events are essential. Therefore, the aim of this study was to review the available injury and illness literature, reporting methods and risk factors in cross-country mountain biking.

Methods

Search engines PubMed, Scopus, CINAHL (EBSCOhost), Scopus, PEDro and the Cochrane Library were systematically searched, and a grey literature search was performed. Narrative analyses of the types, severity and area of injuries and illness type and severity were performed as pooling of data was impossible due to insufficient high-quality studies with the same injury and illness definitions.

Results

Seven studies comprising 28,021 participants were included for analysis. Four to 71% of participants sustained an injury in a cross-country mountain bike event. Injuries to the skin were the most common, followed by bony injuries and concussion. Five to 47% of cyclists reported the onset of gastrointestinal symptoms post-event. The prevalence of illness during events ranged from 0.5 to 23.0%.

Conclusion

The injury and illness definitions were varied and prevented clear comparisons between studies. Injury and illness present a concern in cross-country marathon mountain biking and should be investigated further to provide the true burden of these during race events.

Registration: This protocol has been registered with PROSPERO International prospective register of systematic reviews (No: CRD42019134586).

Diffusion Tensor Imaging in Sport-Related Concussion: A Systematic Review Using an a priori Quality Rating System

Diffusion tensor imaging (DTI) of brain white matter (WM) may be useful for characterizing the nature and degree of brain injury after sport-related concussion (SRC) and assist in establishing objective diagnostic and prognostic biomarkers. This study aimed to conduct a systematic review using an a priori quality rating strategy to determine the most consistent DTI-WM changes post-SRC. Articles published in English (until June 2020) were retrieved by standard research engine and gray literature searches (N = 4932), using PRISMA guidelines. Eligible studies were non-interventional naturalistic original studies that conducted DTI within 6 months of SRC in current athletes from all levels of play, types of sports, and sex. A total of 29 articles were included in the review, and after quality appraisal by two raters, data from 10 studies were extracted after being identified as high quality. High-quality studies showed widespread moderate-to-large WM differences when SRC samples were compared to controls during the acute to early chronic stage (days to weeks) post-SRC, including both increased and decreased fractional anisotropy and axial diffusivity and decreased mean diffusivity and radial diffusivity. WM differences remained stable in the chronic stage (2-6 months post-SRC). DTI metrics were commonly associated with SRC symptom severity, although standardized SRC diagnostics would improve future research. This indicates that microstructural recovery is often incomplete at return to play and may lag behind clinically assessed recovery measures. Future work should explore interindividual trajectories to improve understanding of the heterogeneous and dynamic WM patterns post-SRC.

Association of Concussion Symptoms With Testosterone Levels and Erectile Dysfunction in Former Professional US-Style Football Players

Question

Are professional US-style football players with a history of multiple concussion symptoms more likely to report indicators of low testosterone levels or erectile dysfunction (ED)?

Findings

In this cross-sectional study of 3409 former players, a monotonically increasing association was found between the number of concussion symptoms and the odds of reporting an indicator of low testosterone level and ED.

Meaning

Concussion symptoms among former football players were associated with low testosterone levels and ED indicators, suggesting that men with a history of head injury may benefit from discussions with their health care clinicians regarding these treatable outcomes.

Importance

Small studies suggest that head trauma in men may be associated with low testosterone levels and sexual dysfunction through mechanisms that likely include hypopituitarism secondary to ischemic injury and pituitary axonal tract damage. Athletes in contact sports may be at risk for pituitary insufficiencies or erectile dysfunction (ED) because of the high number of head traumas experienced during their careers. Whether multiple symptomatic concussive events are associated with later indicators of low testosterone levels and ED is unknown.

Objective

To explore the associations between concussion symptom history and participant-reported indicators of low testosterone levels and ED.

Design, Setting, and Participants

This cross-sectional study of former professional US-style football players was conducted in Boston, Massachusetts, from January 2015 to March 2017. Surveys on past football exposures, demographic factors, and current health conditions were sent via electronic and postal mail to participants within and outside of the United States. Analyses were conducted in Boston, Massachusetts; the data analysis began in March 2018 and additional analyses were performed through June 2019. Of the 13 720 male former players eligible to enroll who were contacted, 3506 (25.6%) responded.

Exposures

Concussion symptom score was calculated by summing the frequency with which participants reported 10 symptoms, such as loss of consciousness, disorientation, nausea, memory problems, and dizziness, at the time of football-related head injury.

Main Outcomes and Measures

Self-reported recommendations or prescriptions for low testosterone or ED medication served as indicators for testosterone insufficiency and ED.

Results

In 3409 former players (mean [SD] age, 52.5 [14.1] years), the prevalence of indicators of low testosterone levels and ED was 18.3% and 22.7%, respectively. The odds of reporting low testosterone levels or ED indicators were elevated for previously established risk factors (eg, diabetes, sleep apnea, and mood disorders). Models adjusted for demographic characteristics, football exposures, and current health factors showed a significant monotonically increasing association of concussion symptom score with the odds of reporting the low testosterone indicator (highest vs lowest quartile, odds ratio, 2.39; 95% CI, 1.79-3.19; P < .001). The ED indicator showed a similar association (highest quartile vs lowest, odds ratio, 1.72; 95% CI, 1.30-2.27; P < .001).

Conclusions and Relevance

Concussion symptoms at the time of injury among former football players were associated with current participant-reported low testosterone levels and ED indicators. These findings suggest that men with a history of head injury may benefit from discussions with their health care clinicians regarding testosterone deficiency and sexual dysfunction.

Blood Biomarkers of Sports-Related Concussion in Pediatric Athletes

OBJECTIVE

To examine changes in blood biomarkers, serum neurofilament light (Nf-L), and plasma tau, as well as the relationship between blood biomarkers and symptom reports, in athletes with a sports-related concussion.

DESIGN

Prospective cohort study.

SETTING

Private community-based concussion clinic.

PARTICIPANTS

Athletes aged 13 to 18 years old with a diagnosed sports-related concussion presenting to a concussion clinic within 7 days of injury and noninjured athletes with no history of concussion aged 13 to 23 years old.

ASSESSMENT AND MAIN OUTCOME MEASURES

Injured athletes provided a blood sample at the initial clinical evaluation and again at least 6 months after injury. Noninjured athletes provided a single blood sample. All participants completed symptom reports during each visit. Statistical comparisons of biomarker concentrations and symptom reports were conducted.

RESULTS

The mean rank for tau was significantly lower for concussed athletes compared with nonconcussed athletes. In contrast, the mean rank of Nf-L was higher for concussed athletes than for nonconcussed athletes, although the difference was nonsignificant. Plasma tau was significantly lower postinjury compared with 6 months after injury, whereas serum Nf-L was significantly higher postinjury. There was a weak but significant inverse relationship observed between tau and the number of symptoms reported, but no relationship was observed between Nf-L and the number of symptoms reported.

CONCLUSIONS

These data indicate that in the days following a sports-related concussion, the blood biomarkers tau and Nf-L display contrasting patterns of change but may not be related to self-reported symptom scores.

The role of diffusion tensor imaging in characterizing injury patterns on athletes with concussion and subconcussive injury: a systematic review

Traumatic brain injury (TBI) is a major public health problem. The majority of TBIs are in the form of mild TBI (also known as concussion) with sports-related concussion (SRC) receiving public attention in recent years.Here we have performed a systematic review of the literature on the use of Diffusion Tensor Imaging (DTI) on sports-related concussion and subconcussive injuries. Our review found different patterns of change in DTI parameters between concussed and subconcussed groups. The Fractional Anisotropy (FA) was either unchanged or increased for the concussion group, while the subconcussed group generally experienced a decrease in FA. A reverse pattern was observed for Mean Diffusivity (MD) - where the concussed group experienced a decrease in MD while the subconcussed group showed an increase in MD. However, in general, discrepancies were observed in the results reported in the literature - likely due to the huge variations in DTI acquisition parameters, and image processing and analysis methods used in these studies. This calls for more comprehensive and well-controlled studies in this field, including those that combine the advanced brain imaging with biomechancial modeling and kinematic sensors - to shed light on the underlying mechanisms behind the structural changes observed from the imaging studies.

Head impact exposures in women's collegiate rugby

Objectives: To describe the incidence, magnitude, and distribution of head impacts and track concussions sustained in a collegiate level women's rugby season. Methods: Data on head impact incidence and magnitude were collected via Smart Impact Monitors (SIM) (Triax Technologies, Inc., Norwalk, CT) within fitted headbands during practices and games of one competitive season. Magnitude data included peak linear acceleration (PLA) and peak rotational velocity (PRV) measurements and were reported as median [IQR]. Results: Players sustained 120 head impacts ≥15 g (18.1 g - 78.9 g) with 1199 total athlete exposures. In eight games, 67 head impacts were recorded with a mean rate of 0.40 ± 0.22 hits per-player per-match, median PLA of 32.2 g, and PRV of 13.5 rad^.sec^-1. There were 53 head impacts in 47 practices with a mean rate of 0.05 ± 0.04 hits per-player per-practice, median PLA of 29.8 g and PRV of 15.7 rad^.sec^-1. Four concussions were reported and monitored. Conclusion: The incidence and magnitude of head impacts in collegiate level women's rugby over one season of practices and games were fewer than those reported in other comparable studies. These findings give insight into the impact burden that female collegiate rugby athletes withstand throughout a competitive season.

Connections between intrinsically photosensitive retinal ganglion cells and TBI symptoms

The majority of patients with traumatic brain injury (TBI) are classified as having a mild TBI. Despite being categorized as mild, these individuals report ongoing and complex symptoms, which negatively affect their ability to complete activities of daily living and overall quality of life. Some of the major symptoms include anxiety, depression, sleep problems, headaches, light sensitivity, and difficulty reading. The root cause for these symptoms is under investigation by many in the field. Of interest, several of these symptoms such as headaches, ocular pain, light sensitivity, and sleep disturbances may overlap and share underlying circuitry influenced by the intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells are light sensing, but non-image forming, and they influence corneal function, pupillary constriction, and circadian rhythm. In this review, we discuss these symptoms and propose a role of the ipRGCs as at least one underlying and unifying cause for such symptoms.

Diagnosing mild traumatic brain injury using saliva RNA compared to cognitive and balance testing

BACKGROUND

Early, accurate diagnosis of mild traumatic brain injury (mTBI) can improve clinical outcomes for patients, but mTBI remains difficult to diagnose because of reliance on subjective symptom reports. An objective biomarker could increase diagnostic accuracy and improve clinical outcomes. The aim of this study was to assess the ability of salivary noncoding RNA (ncRNA) to serve as a diagnostic adjunct to current clinical tools. We hypothesized that saliva ncRNA levels would demonstrate comparable accuracy for identifying mTBI as measures of symptom burden, neurocognition, and balance.

METHODS

This case-control study involved 538 individuals. Participants included 251 individuals with mTBI, enrolled ≤14 days postinjury, from 11 clinical sites. Saliva samples (n = 679) were collected at five time points (≤3, 4-7, 8-14, 15-30, and 31-60 days post-mTBI). Levels of ncRNAs (microRNAs, small nucleolar RNAs, and piwi-interacting RNAs) were quantified within each sample using RNA sequencing. The first sample from each mTBI participant was compared to saliva samples from 287 controls. Samples were divided into testing (n = 430; mTBI = 201 and control = 239) and training sets (n = 108; mTBI = 50 and control = 58). The test set was used to identify ncRNA diagnostic candidates and create a diagnostic model. Model accuracy was assessed in the naïve test set.

RESULTS

A model utilizing seven ncRNA ratios, along with participant age and chronic headache status, differentiated mTBI and control participants with a cross-validated area under the curve (AUC) of .857 in the training set (95% CI, .816-.903) and .823 in the naïve test set. In a subset of participants (n = 321; mTBI = 176 and control = 145) assessed for symptom burden (Post-Concussion Symptom Scale), as well as neurocognition and balance (ClearEdge System), these clinical measures yielded cross-validated AUC of .835 (95% CI, .782-.880) and .853 (95% CI, .803-.899), respectively. A model employing symptom burden and four neurocognitive measures identified mTBI participants with similar AUC (.888; CI, .845-.925) as symptom burden and four ncRNAs (.932; 95% CI, .890-.965).

CONCLUSION

Salivary ncRNA levels represent a noninvasive, biologic measure that can aid objective, accurate diagnosis of mTBI.

Assessment of Long-Term Effects of Sports-Related Concussions: Biological Mechanisms and Exosomal Biomarkers

Concussion or mild traumatic brain injury (mTBI) in athletes can cause persistent symptoms, known as post-concussion syndrome (PCS), and repeated injuries may increase the long-term risk for an athlete to develop neurodegenerative diseases such as chronic traumatic encephalopathy (CTE), and Alzheimer's disease (AD). The Center for Disease Control estimates that up to 3.8 million sport-related mTBI are reported each year in the United States. Despite the magnitude of the phenomenon, there is a current lack of comprehensive prognostic indicators and research has shown that available monitoring tools are moderately sensitive to short-term concussion effects but less sensitive to long-term consequences. The overall aim of this review is to discuss novel, quantitative, and objective measurements that can predict long-term outcomes following repeated sports-related mTBIs. The specific objectives were (1) to provide an overview of the current clinical and biomechanical tools available to health practitioners to ensure recovery after mTBIs, (2) to synthesize potential biological mechanisms in animal models underlying the long-term adverse consequences of mTBIs, (3) to discuss the possible link between repeated mTBI and neurodegenerative diseases, and (4) to discuss the current knowledge about fluid biomarkers for mTBIs with a focus on novel exosomal biomarkers. The conclusions from this review are that current post-concussion clinical tests are not sufficiently sensitive to injury and do not accurately quantify post-concussion alterations associated with repeated mTBIs. In the current review, it is proposed that current practices should be amended to include a repeated symptom inventory, a cognitive assessment of executive function and impulse control, an instrumented assessment of balance, vestibulo-ocular assessments, and an improved panel of blood or exosome biomarkers.

Radiographic and neurobehavioral profile of sports-related concussion associated with scholastic wrestling: a case report

Sports-related concussions (SRCs) are typically characterized by transient neurologic deficits due to physiologic and metabolic brain injury. However, following an SRC, subsequent insults may lead to severe and permanent injury in the affected brain cells. We present the case of a 15-year-old female scholastic wrestler who developed acute encephalopathy, macroscopic white matter injury on imaging, and chronic behavioral changes from inadequate neuro-recovery after a documented SRC. We also compare her case with established SRC data, demonstrating that wrestling-related concussions and repetitive head impacts can produce similar degrees of diffuse neuroinflammation, myelinated axonopathy, blood-brain barrier disruption, and post-concussive symptoms.

Disparities in baseline neurocognitive testing for student concussion management in Massachusetts high schools

PURPOSE

There is evidence of socioeconomic disparities with respect to the implementation of student-sports concussion laws nationally. The purpose of this study was to examine school sociodemographic characteristics associated with the provision of computerised baseline neurocognitive testing (BNT) in Massachusetts (MA) high schools, and to assess whether the scope of testing is associated with the economic status of student populations in MA.

METHODS

A cross-sectional secondary analysis of surveys conducted with MA athletic directors (n=270) was employed to investigate school characteristics associated with the provision of BNT. Correlation and regression analyses were used to assess whether the scope of testing is associated with the economic status of student populations in MA.

RESULTS

The scope of BNT was independently associated with the economic disadvantage rate (EDR) of the student population (β=-0.02, p=0.01); whether or not the school employs an athletic trainer (AT) (β=0.43, p=0.03); and school size (β=-0.54, p=0.03). In a multivariable regression model, EDR was significantly associated with the scope of baseline testing, while controlling for AT and size (β=-0.01, p=0.03, adj-R2=0.1135).

CONCLUSION

Among public high schools in MA, disparities in the provision of BNT for students are associated with the economic characteristics of the student body. Schools that have a greater proportion of low-income students are less likely to provide comprehensive BNT. The clinical implications of not receiving BNT prior to concussion may include diminished quality of postconcussive care, which can have short-term and long-term social, health-related and educational impacts.

Sports-Injury Encephalopathy

Sports-related encephalopathies are a growing concern among athletes who have experienced head trauma. Anxiety is heightened for the public and especially among parents of children playing contact sports. The most common neuropsychological conditions are concussions and traumatic encephalopathies. Concussions result from brain traumas that can be asymptomatic, but more serious concussions can include loss of consciousness, neurological abnormalities, and/or posttraumatic amnesias. Repetitive concussions lead to persistent brain pathology, known as chronic traumatic encephalopathies. This gradually progressive neurodegenerative disease frequently presents with cognitive and neurological deficits, which can result in significant parkinsonian features and dementia. Imaging studies may be noncontributory; however, diffusion tensor imaging, magnetic resonance spectroscopy, and functional magnetic resonance imaging can detect changes indicative of these encephalopathies. Progressive neuronal degeneration with tau proteins are documented on pathological examination. Prevention, early diagnosis, and proper treatment are the recommended approach to these conditions.

Hypogonadism in Exercising Males: Dysfunction or Adaptive-Regulatory Adjustment?

For decades researchers have reported men who engaged in intensive exercise training can develop low resting testosterone levels, alterations in their hypothalamic-pituitary-gonadal (HPG) axis, and display hypogonadism. Recently there is renewed interest in this topic since the International Olympic Committee (IOC) Medical Commission coined the term "Relative Energy Deficiency in Sports" (RED-S) as clinical terminology to address both the female-male occurrences of reproductive system health disruptions associated with exercise. This IOC Commission action attempted to move beyond the sex-specific terminology of the "Female Athlete Triad" (Triad) and heighten awareness/realization that some athletic men do have reproductive related physiologic disturbances such as lowered sex hormone levels, HPG regulatory axis alterations, and low bone mineral density similar to Triad women. There are elements in the development and symptomology of exercise-related male hypogonadism that mirror closely that of women experiencing the Triad/RED-S, but evidence also exists that dissimilarities exist between the sexes on this issue. Our research group postulates that the inconsistency and differences in the male findings in relation to women with Triad/RED-S are not just due to sex dimorphism, but that there are varying forms of exercise-related reproductive disruptions existing in athletic men resulting in them displaying a relative hypogonadism condition. Specifically, such conditions in men may derive acutely and be associated with low energy availability (Triad/RED-S) or excessive training load (overtraining) and appear transient in nature, and resolve with appropriate clinical interventions. However, manifestations of a more chronic based hypogonadism that persists on a more permanent basis (years) exist and is termed the "Exercise Hypogonadal Male Condition." This article presents an up-to-date overview of the various types of acute and chronic relative hypogonadism found in athletic, exercising men and proposes mechanistic models of how these various forms of exercise relative hypogonadism develop.

A New Index of Coordinated Posterior and Anterior Evoked EEG to Detect Recall Under Sedation - A Pilot Study

EEG-based technologies may be limited in identifying recall under sedation (RUS). We developed a novel index, posteriorization/anteriorization (P/A) index, based on auditory evoked EEG signal and assessed whether it could differentiate between patients with or without RUS. Methods: EEG and BIS were sampled from 3 groups: 1. Patients undergoing sedation (n = 26); 2. Awake volunteers (n = 13, positive control for recall) 3. Patients undergoing general anesthesia (GA, n = 12, negative control for recall). In recovery, recall was assessed using the BRICE questionnaire. Of the 26 sedated patients, 12 experienced recall. Both The P/A index and BIS differentiated between patients with recall and no recall. However, BIS differentiation may have been sensitive to the main drug used for sedation (midazolam vs. propofol) and the P/A index did not show similar drug-based sensitivity. Furthermore, only BIS results were correlated with EMG. Conclusion: This pilot study provided support for the association between P/A index and recall after sedation. Further research is needed in integrating the index into clinical use: (1) it should be derived by an easy-to-use EEG system with a better signal-to-noise ratio; (2) its applicability to other drugs must be shown.

A novel clinical practice tool increases patients’ understanding of concussion care within an inter-disciplinary clinic

Background

Concussion patients who experience prolonged symptoms may benefit from evidence-based, physician-led, inter-disciplinary care. The success of this approach may depend on a patient’s understanding and adherence to a complex, multi-modal recovery process.

Objectives

We have developed a novel clinical care guide for post-injury concussion caretermed the “Treatment Passport,” intended to facilitate greater communication and understanding among patients, healthcare providers, family members, teachers, and coaches. This study aims to assess whether the Treatment Passport increases patients’ understanding of their concussion care in an inter-disciplinary setting.

Methods

Patients presenting with sports- or recreation-related concussions were randomly assigned to the intervention ( n = 15) or control ( n = 18) group. Subjects in the control group received physician-led, inter-disciplinary care, while subjects in the intervention group received the same care, but with the addition of the Treatment Passport. After four weeks of treatment, participants in both groups completed an 11-question survey to assess their understanding of inter-disciplinary concussion care.

Results

The median age of participants was 20 (range 10–63). Participants in the intervention group showed significant increases in their understanding of inter-disciplinary concussion care when compared to control group members. This was reflected in a 2.1–2.8-fold greater understanding of the cognitive, physical, and vestibular aspects of their care. In addition, 86.7% of control group participants indicated they believed that the Treatment Passport would have helped with their concussion recovery journey.

Conclusion

The Treatment Passport is a novel clinical tool that facilitates the delivery of standardized inter-disciplinary concussion care by increasing patient-caregiver communication and understanding.

Prior head injury but not sex or sports-participation affects expectations for post-injury rest and activity in simulated mild traumatic brain injury

Rest acutely followed by a gradual return to activity is commonly recommended for mild traumatic brain injury (TBI). However, the general public's rest and activity expectations for this injury are unknown, as are the individual factors that might affect them. 165 individuals completed an online survey. A series of between-groups comparisons of expectations for the week following a mild TBI was performed. The comparisons were between individuals with or without a prior mild TBI; sports-playing versus non-sports-playing individuals, and; females versus males. Expectations were elicited for 39 everyday behaviours referred to in mild TBI patient advice. Compared to a rating indicating 'no change' in the amount of pre-injury activity, "rest" was expected for 37 items (p's < .05). Expectations were not different based on participants' sex or sports-participation. However, for seven predominantly cognitive items such as studying, a prior injury increased rest expectations (p < .05; small-to-medium effects). The findings indicate that whilst the proposed activity restrictions are appropriate for some circumstances such as acutely postinjury, they have the potential to be overly strong. To address this potential, especially with first-ever injury, clinicians and sports officials should check their patient's postinjury rest and activity plans when providing active rest advice.

Trends in concussions at Ontario schools prior to and subsequent to the introduction of a concussion policy - an analysis of the Canadian hospitals injury reporting and prevention program from 2009 to 2016

BACKGROUND

Concussion is a preventable injury that can have long-term health consequences for children and youth. In Ontario, the Policy/Program Memorandum # 158 (PPM) was introduced by the Ministry of Education of Ontario in March 2014. The PPM's main purpose is to require each school board in the province to create and implement a concussion policy. The purpose of this paper is to examine trends in school-based concussions prior to and subsequent to the introduction of the PPM.

METHODS

This report examined emergency department (ED) visits in 5 Ontario hospitals that are part of the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP), and compared trends over time in diagnosed concussions, and suspected concussions identified as "other head injury" in children and youth aged 4-18.

RESULTS

From 2009 to 2016 study years, there were 21,094 suspected concussions, including 8934 diagnosed concussions in youth aged 4-18. The average number of diagnosed concussions in the 5 years before the PPM was 89 concussions/month, compared to approximately 117 concussions per month after; a 30% increase in the monthly rate of concussions presenting to the ED. The total number of concussion or head injury-related ED visits remained relatively unchanged but the proportion of diagnosed concussions rose from 31% in 2009 to 53% in 2016. The proportion of diagnosed concussions in females also increased from 38% in 2013 to 46% in 2016. The percent of all diagnosed concussions occurring at schools increased throughout the study reaching almost 50% in 2016 with most injuries taking place at the playground (24%), gymnasium (22%) or sports field (20%).

CONCLUSIONS

The introduction of the PPM may have contributed to a general increase in concussion awareness and an improvement in concussion identification at the school level in children and youth aged 4-18.

Clinical features and early detection of sport-related concussion

Aim

Athletes who suffer sport‐related concussions but continue playing have a high probability of experiencing more severe symptoms with any subsequent concussion. This study used data from the authors’ clinical department to retrospectively investigate the clinical characteristics of sport‐related concussion and factors associated with delays in examinations.

Methods

The study included 38 patients with sport‐related concussions who were treated at the authors’ hospital. The sports during which the injuries occurred, occasions of injury, factors affecting the time from injury until examination at hospital, and prognoses were evaluated retrospectively.

Results

Sport‐related concussions most frequently occurred in rugby and judo, where tackling, throwing, and other types of physical contact can result in impacts to the head region at high angular or linear velocity with acceleration. Some subjects showed consciousness disturbance and/or clear subjective symptoms immediately after the injury and were therefore examined at the hospital rapidly. However, other subjects who suffered amnesia or less obvious symptoms continued to play after the injury and had delayed examinations. In addition, there was a tendency for examinations to be delayed when an on‐site physician was present.

Conclusions

In contact sports where injury‐resulting events occur, such as impacts to the head at high angular or linear velocity with acceleration, athletes should be immediately withdrawn from play and evaluated for concussion, even if there are no obvious head injuries or symptoms. The immediate ascertainment of symptoms after physical contact would improve the rapid detection of sport‐related concussion.

The Mild Traumatic Brain Injury Rest and Activity Questionnaire (MTBI-RAQ): A Pilot Study

Objective: To develop a tool for assessing intentions to continue or change activities for recovery following mild traumatic brain injury (mTBI) and determine if they are dependent on injury context or activity type. Method: Adult volunteers with no (or no recent) history of mTBI were randomly allocated to one of two vignette conditions, each with a different injury context. The vignette described an mTBI due to a motor vehicle accident (MVA, n = 76) or sport (SPORT, n = 89). Volunteers reported their rest or activity plans for 39 behaviours comprising three behaviour types (cognitive, physical, and restful). Results: Compared to a cut-score representing no change, on average there was a significant (p <= .001) planned decrease in physical and cognitive behaviours (MVAphysicalt(53) = 7.373; SPORTphysicalt(41) = 9.281; MVAcognitivet(41) = 9.367; SPORTcognitivet(51) = −3.521) and a significant planned increase in restful behaviours, such as sleep (MVArestfult(72) = 10.006; SPORTrestfult(86) = 9.566). An overall within-group effect for behaviour-type was not identified and there was no effect of condition (MVA vs. SPORT). Conclusion: The acute rest and activity plans for a simulated mTBI are behaviour specific and not dependent on context. An expectation for blanket-rest was not was observed but rest was planned for specific behaviours. This tool could be used to guide discussions with mTBI patients about their recovery so that their plans align with advice, and it could aid further research into the relation between intended and actual rest and activity and the effect on eventual outcomes.

Concussion diagnoses among adults presenting to three Canadian emergency departments: Missed opportunities

OBJECTIVES

Patients with concussion commonly present to the emergency department (ED) for assessment. Misdiagnosis of concussion has been documented in children and likely impacts treatment and discharge instructions. This study aimed to examine diagnosis of concussion in a general adult population.

METHODS

Patients >17years old presenting meeting the World Health Organization's definition of concussion were recruited in one academic (Hospital 1) and two community (Hospitals 2 and 3) EDs in a Canadian city. A physician questionnaire and patient interviews documented recommendations given by emergency physicians. Bi-variable comparisons are reported using chi-square tests, t-tests or Mann-Whitney tests, as appropriate. Multivariate analyses were performed using logistic regression methods.

RESULTS

Overall, the study enrolled 250 patients. The median age was 35 (IQR: 23 to 49) and 52% were female. A variety of concussion causes were documented. Forty-one (16%) patients were not diagnosed with a concussion despite meeting criteria. Concussion diagnosis was less likely with a longer ED length of stay (OR=0.71; 95% CI: 0.60 to 0.83), presenting to the non-academic centers (Hospital 2: OR=0.21, 95% CI: 0.08 to 0.58; Hospital 3: OR=0.07, 95% CI: 0.02 to 0.24), or involvement in a motor vehicle collision (OR=0.11; 95% CI: 0.03 to 0.46).

CONCLUSION

One in six patients with concussion signs and symptoms were misdiagnosed in the ED. Misdiagnosis was related to injury mechanism, length of stay, and enrolment site. Closer examination of institutional factors is needed to identify effective strategies to promote accurate diagnosis of concussion.

Emergency Physician Training on Mild Traumatic Brain Injury: A Systematic Review

OBJECTIVES

Mild traumatic brain injury (mTBI) is the most common emergency department (ED) brain injury presentation worldwide. Despite its frequency, practice variation and care gaps exist among emergency physicians (EPs) in diagnosing and appropriately managing mTBI in the ED. The objective of this review was to identify mTBI-specific training undertaken to improve the detection and management of mTBIs by EPs and its impact on practice.

METHODS

A comprehensive search strategy utilized four bibliographic databases, the gray literature and the keywords concussion, mild traumatic brain injury, medical education, and continuing medical education (CME). To be included, studies were required to report on mTBI training received by practicing EPs at any point during their medical education or career. Studies examining clinical practice guidelines or use of diagnostic tools without active implementation or formal training were not included. Two reviewers screened unique citations for relevance and reviewed the full texts of relevant articles. Two independent researchers extracted data and assessed methodologic quality. At all stages, a third independent reviewer adjudicated discrepancies.

RESULTS

Overall, five studies were included from 409 unique results. None of the included studies were of high quality. Identified training on mTBI consisted of three training toolkits, conference presentations and academic journal articles, and pediatric fellowship training. Training primarily occurred as CME and focused on awareness of and management of mTBI; three studies reported physician practice changes, including increases in the use of evidence-based return-to-school and return-to-activity recommendations.

CONCLUSIONS

The few studies identified addressing mTBI training targeting EPs demonstrate the limited attention given to this issue. The current evidence-to-practice gap in mTBI management places patients at risk for suboptimal care in the ED, and existing mTBI knowledge translation, including education, requires optimization to effectively address the current gap in evidence-based practice for mTBI diagnosis and management in the ED.

Twitter and traumatic brain injury: A content and sentiment analysis of tweets pertaining to sport-related brain injury

Objectives:

Sport-related traumatic brain injuries are a significant public health burden, with hundreds of thousands sustained annually in North America. While sports offer numerous physical and social health benefits, traumatic brain injuries such as concussion can seriously impact a player’s life, athletic career, and sport enjoyment. The culture in many sports encourages winning at all costs, placing athletes at risk for traumatic brain injuries. As social media has become a central part of everyday life, the content of users’ messages often reflects the prevailing culture related to a particular event or health issue.

Methods:

We hypothesized that Twitter data might be useful for understanding public perceptions and misperceptions of sport-related traumatic brain injuries. We performed a content and sentiment analysis of 7483 Twitter^® tweets related to traumatic brain injuries in sports collected during June and July 2013.

Results:

We identified five major themes. Users tweeted about personal traumatic brain injuries experiences, reported traumatic brain injuries in professional athletes, shared research about sport-related concussions, and discussed policy and safety in injury prevention, such as helmet use. We identified mixed perceptions of and sentiment toward traumatic brain injuries in sports: both an understanding that brain injuries are serious and disregard for activities that might reduce the public burden of traumatic brain injuries were prevalent in our Twitter analysis.

Conclusion:

While the scientific and medical community considers a concussion a form of traumatic brain injuries, our study demonstrates a misunderstanding of this fact among the public. In our current digital age, social media can provide useful insight into the culture around a health issue, facilitating implementation of prevention and treatment strategies.

Fusion or Fission: The Destiny of Mitochondria In Traumatic Brain Injury of Different Severities

Mitochondrial dynamics are regulated by a complex system of proteins representing the mitochondrial quality control (MQC). MQC balances antagonistic forces of fusion and fission determining mitochondrial and cell fates. In several neurological disorders, dysfunctional mitochondria show significant changes in gene and protein expression of the MQC and contribute to the pathophysiological mechanisms of cell damage. In this study, we evaluated the main gene and protein expression involved in the MQC in rats receiving traumatic brain injury (TBI) of different severities. At 6, 24, 48 and 120 hours after mild TBI (mTBI) or severe TBI (sTBI), gene and protein expressions of fusion and fission were measured in brain tissue homogenates. Compared to intact brain controls, results showed that genes and proteins inducing fusion or fission were upregulated and downregulated, respectively, in mTBI, but downregulated and upregulated, respectively, in sTBI. In particular, OPA1, regulating inner membrane dynamics, cristae remodelling, oxidative phosphorylation, was post-translationally cleaved generating differential amounts of long and short OPA1 in mTBI and sTBI. Corroborated by data referring to citrate synthase, these results confirm the transitory (mTBI) or permanent (sTBI) mitochondrial dysfunction, enhancing MQC importance to maintain cell functions and indicating in OPA1 an attractive potential therapeutic target for TBI.

The effect of repetitive subconcussive collisions on brain integrity in collegiate football players over a single football season: A multi-modal neuroimaging study

The cumulative effect of repetitive subconcussive collisions on the structural and functional integrity of the brain remains largely unknown. Athletes in collision sports, like football, experience a large number of impacts across a single season of play. The majority of these impacts, however, are generally overlooked, and their long-term consequences remain poorly understood. This study sought to examine the effects of repetitive collisions across a single competitive season in NCAA Football Bowl Subdivision athletes using advanced neuroimaging approaches. Players were evaluated before and after the season using multiple MRI sequences, including T₁-weighted imaging, diffusion tensor imaging (DTI), arterial spin labeling (ASL), resting-state functional MRI (rs-fMRI), and susceptibility weighted imaging (SWI). While no significant differences were found between pre- and post-season for DTI metrics or cortical volumes, seed-based analysis of rs-fMRI revealed significant (p < 0.05) changes in functional connections to right isthmus of the cingulate cortex (ICC), left ICC, and left hippocampus. ASL data revealed significant (p < 0.05) increases in global cerebral blood flow (CBF), with a specific regional increase in right postcentral gyrus. SWI data revealed that 44% of the players exhibited outlier rates (p < 0.05) of regional decreases in SWI signal. Of key interest, athletes in whom changes in rs-fMRI, CBF and SWI were observed were more likely to have experienced high G impacts on a daily basis. These findings are indicative of potential pathophysiological changes in brain integrity arising from only a single season of participation in the NCAA Football Bowl Subdivision, even in the absence of clinical symptoms or a diagnosis of concussion. Whether these changes reflect compensatory adaptation to cumulative head impacts or more lasting alteration of brain integrity remains to be further explored.

The Impact of Traumatic Brain Injury on the Aging Brain

Traumatic brain injury (TBI) has come to the forefront of both the scientific and popular culture. Specifically, sports-related concussions or mild TBI (mTBI) has become the center of scientific scrutiny with a large amount of research focusing on the long-term sequela of this type of injury. As the populace continues to age, the impact of TBI on the aging brain will become clearer. Currently, reports have come to light that link TBI to neurodegenerative disorders such as Alzheimer's and Parkinson's diseases, as well as certain psychiatric diseases. Whether these associations are causations, however, is yet to be determined. Other long-term sequelae, such as chronic traumatic encephalopathy (CTE), appear to be associated with repetitive injuries. Going forward, as we gain better understanding of the pathophysiological process involved in TBI and subclinical head traumas, and individual traits that influence susceptibility to neurocognitive diseases, a clearer, more comprehensive understanding of the connection between brain injury and resultant disease processes in the aging brain will become evident.

Treatment of persistent post-concussion syndrome due to mild traumatic brain injury: current status and future directions

Persistent post-concussion syndrome caused by mild traumatic brain injury has become a major cause of morbidity and poor quality of life. Unlike the acute care of concussion, there is no consensus for treatment of chronic symptoms. Moreover, most of the pharmacologic and non-pharmacologic treatments have failed to demonstrate significant efficacy on both the clinical symptoms as well as the pathophysiologic cascade responsible for the permanent brain injury. This article reviews the pathophysiology of PCS, the diagnostic tools and criteria, the current available treatments including pharmacotherapy and different cognitive rehabilitation programs, and promising new treatment directions. A most promising new direction is the use of hyperbaric oxygen therapy, which targets the basic pathological processes responsible for post-concussion symptoms; it is discussed here in depth.