Concussions and their consequences: current diagnosis, management and prevention

SCAT Symptom Evolution in the Acute Concussion Phase: Findings From the NCAA-DoD CARE Consortium

The Sport Concussion Assessment Tool (SCAT) is the most widely used tool following sport-related concussion (SRC). Initial SCAT symptom burden is a strong predictor of recovery in collegiate athletes; however, it is unknown if symptom presentation varies within the acute (<48 hours) post-SRC phase. The purpose of this cohort study was to examine acute SRC symptom presentation among National Collegiate Athletic Association (NCAA) athletes. Concussed NCAA varsity athletes (n=1,780) from thirty universities across the United States that participated in the Concussion Assessment, Research, and Education (CARE) Consortium were included. Time of injury occurrence and SCAT administration data were recorded, from which time-to-SCAT (hours, continuous) was calculated. The main outcome was SCAT total symptom severity [(TSS), 0-126]. Multivariable negative binomial regression was used to examine the association between time (hours) since injury and TSS. Covariates included sex, previous concussion, sport contact level, amnesia/loss of consciousness, immediate reporting of injury, and injury situation. A random effect (person level) accounted for multiple assessments. TSS score ratios (SR) with associated 95% confidence intervals (CI) were provided. The SCAT was administered an average of 14 (25th-75th percentile: 1.2-24) hours post-SRC, and average TSS was 27.35±21.28 across all participants. Time-to-SCAT was associated with a 1% decrease in TSS after adjusting for covariate effects (SR: 0.99, 95% CI: 0.99-0.99, p<0.001). Overall, we observed a small, but significant decrease in TSS with each hour post-SRC. Assessing a concussed athlete once in the acute phase will likely provide a sufficient sense of their symptomatic well-being, as measures did not fluctuate dramatically. Future research should aim to examine how acute symptom evolution influences recovery metrics.

Critical gap in practice-lack of attention to falls and possible fall-related post-concussion symptoms in older adults and individuals with neurodegenerative disease

Falls in older adults and those with neurodegenerative disease (ND) are a current public health hazard and the primary cause of sustaining a mild traumatic brain injury (mTBI)/concussion. Little is known regarding how post-concussion symptoms present in older adults and patients with ND, even though they are the demographic at highest risk. A combination of under-reporting of falls and a lack of awareness regarding potential consequences of falls, results in the underdiagnosis of post-fall issues and concussions in this population. Our aim was to conduct a quality assessment survey to assess physician practice regarding falls and their general knowledge of concussion symptoms. We sent surveys through email to 1400 North American physicians, mostly those working at university affiliated hospitals, who specialized in seeing older adults and patients with ND. One hundred forty-one physicians completed the survey. 71.4% of all responding physicians either never inquired or inquired in less than 5% of their patients with ND or older adult patients, about history of falls. Over half of the physicians (51.8%) either never ask or do not consider it necessary to ask about concussion symptoms post-fall. The majority of physicians (92%) recognized that concussions can have lasting effects on patients, particularly on mood and demonstrated good knowledge of post-concussion symptoms by correctly identifying them. Additionally, more than 70% of responding physicians believed that patients with ND or older adults can fully recover from a concussion with the same probability as any other age group if treated. Only 50% of physicians felt confident in managing post-concussion symptoms themselves, 53.9% of physicians did not know of, or did not have nearby concussion clinics to refer patients to. The gaps in practice are clearly reflective of the gaps in the literature regarding falls and concussions in older adults and ND patients. There is a very low rate of physician inquiry about history of falls and concussion symptoms in older patients and those with NDs. Failure to recognize a concussion, can lead to missed opportunities for targeted interventions to address reversible symptoms. Additionally, the misattribution of post-concussion symptoms to disease progression in older patients or those with NDs may delay and hinder appropriate management.

What traditional neuropsychological assessment got wrong about mild traumatic brain injury. II: limitations in test development, research design, statistical and psychometric issues

PRIMARY OBJECTIVE

This is Part II of a four-part opinion review on traditional neuropsychological assessment methods and findings associated with mild traumatic brain injury (mTBI). This Part II review focuses on historical, psychometric and statistical issues involving traditional neuropsychological methods that have been used in neuropsychological outcome studies of mTBI, but demonstrates the critical limitations of traditional methods.

RESEARCH DESIGN

This is an opinion review.

METHODS AND PROCEDURES

Traditional neuropsychological tests are dated and lack specificity in evaluating such a heterogenous and complex injury as occurs with mTBI.

MAIN OUTCOME AND RESULTS

In this review, we demonstrate traditional neuropsychological methods were never developed as standalone measures for detecting subtle changes in neurocognitive or neurobehavioral functioning and likewise, never designed to address the multifaceted issues related to underlying mTBI neuropathology symptom burden from having sustained a concussive brain injury.

CONCLUSIONS

For neuropsychological assessment to continue to contribute to clinical practice and outcome literature involving mTBI, major innovative changes are needed that will likely require technological advances of novel assessment techniques more specifically directed to evaluating the mTBI patient. These will be discussed in Part IV.

Differences in Volatile Organic Compounds Between Concussed and Non-concussed Division I Athletes

Introduction Diagnosing a concussion is challenging because of complex and variable symptoms. Establishing a viable biomarker of injury may rely on physiologic measurements rather than symptomology. Volatile organic compounds (VOCs) such as breath acetone have been identified as potential physiological markers that can capture changes in the utilization of energy substrates post-concussion. Here, we aimed to explore whether differences in VOCs exist between concussed and non-concussed athletes at the initial and later stages of injury recovery. Methods Six (N=6) non-concussed athletes were enrolled as control participants prior to the competitive season. Control participants' breath acetone, heart rate, and anthropometric measures were obtained at rest and throughout a single exercise challenge by breathalyzer. Six (N=6) athletes diagnosed with concussion during the competitive season had breath acetone measured daily until cleared to return to activity or approximately four weeks following enrollment where they participated in an exit exercise challenge having breath acetone, heart rate, and anthropometric measures obtained. Comparisons were made between at-rest measures of concussed and non-concussed participants at multiple time points during the recovery period. Paired t-test comparisons with individuals serving as their own control were used to determine individual differences in recovery. Visual graphs were used to demonstrate differences in obtained measures amongst individuals and between groups during the exercise challenges. Results Results demonstrated statistically significant differences in breath acetone between concussed and control participants when the highest day measured during the first week of concussion was compared to the control participant's resting values (P=0.017). Additionally, when the concussed participants served as their own control and their highest measured day of the first week post-concussion was compared to values when cleared to return to activity or at 26 days post-concussion, there was a significant difference in breath acetone (P=0.028). Comparing breath acetone during exercise between non-concussed and cleared concussed participants or four weeks post-injury, demonstrated no significant differences throughout the challenge or at rest prior. Visual graph comparisons in a single participant before and after concussion suggest differences may appear following exercise during the recovery period. Discussion These results suggest VOCs, particularly breath acetone, have the potential to serve as diagnostic markers of concussion. However, longitudinal research within larger cohorts and with equipment able to expel VOCs other than acetone from measures are needed to make informed recommendations.

Gene Expression Alterations in Peripheral Blood Following Sport-Related Concussion in a Prospective Cohort of Collegiate Athletes: A Concussion Assessment, Research and Education (CARE) Consortium Study

BACKGROUND

Molecular-based approaches to understanding concussion pathophysiology provide complex biological information that can advance concussion research and identify potential diagnostic and/or prognostic biomarkers of injury.

OBJECTIVE

The aim of this study was to identify gene expression changes in peripheral blood that are initiated following concussion and are relevant to concussion response and recovery.

METHODS

We analyzed whole blood transcriptomes in a large cohort of concussed and control collegiate athletes who were participating in the multicenter prospective cohort Concussion Assessment, Research, and Education (CARE) Consortium study. Blood samples were collected from collegiate athletes at preseason (baseline), within 6 h of concussion injury, and at four additional prescribed time points spanning 24 h to 6 months post-injury. RNA sequencing was performed on samples from 230 concussed, 130 contact control, and 102 non-contact control athletes. Differential gene expression and deconvolution analysis were performed at each time point relative to baseline.

RESULTS

Cytokine and immune response signaling pathways were activated immediately after concussion, but at later time points these pathways appeared to be suppressed relative to the contact control group. We also found that the proportion of neutrophils increased and natural killer cells decreased in the blood following concussion.

CONCLUSIONS

Transcriptome signatures in the blood reflect the known pathophysiology of concussion and may be useful for defining the immediate biological response and the time course for recovery. In addition, the identified immune response pathways and changes in immune cell type proportions following a concussion may inform future treatment strategies.

Overview of Treatment Options for Mild Traumatic Brain Injury: A Literature Review

The incidence and prevalence of concussion, a type of mild traumatic brain injury (mTBI), have steadily increased among athletes, both students and professionals, across a wide variety of sports, including, but not limited to, swimming, tennis, football, and boxing. Recent data have demonstrated that sports are one of the leading causes of concussions among student athletes. While the exact mechanism of concussion onset has yet to be fully elucidated, data suggest that the pathophysiology involves rotational acceleration and deceleration of the brain, leading to axon tearing and disturbance in the metabolic cascade of glucose. Concussive events can have debilitating effects on an athlete, including chronic traumatic encephalopathy (gradual degeneration of brain tissue) that is related to personality changes, emotional disorders, and even dementia. Common symptoms associated with concussion include dizziness, nausea, vomiting, and headaches. The physical assessment consists of a combination of tools involving the mental status examination, vital signs, cervical spine exam, eye exam, and neurological testing. The use of osteopathic manipulative medicine (OMM), pharmacotherapy, hyperbaric oxygen therapy (HBOT), aerobic exercise, balance, and/or vestibular therapy are many common treatment approaches for concussion and post-concussion sequelae. This literature review aims to provide insight into concussions, the current treatment options available, and the new developments in concussions per the Amsterdam 2022 International Consensus Statement on Concussion in Sport published in 2023.

Concussions: A Review of Physiological Changes and Long-Term Sequelae

A concussion is a type of mild traumatic brain injury (mTBI). It is prevalent among athletes across a wide variety of sports. The exact mechanism of a concussion is unknown, but it is currently accepted that the acceleration and deceleration of the brain is the insult causing disturbances in activity. The most common symptoms of concussions include but are not limited to dizziness, nausea, vomiting, and headaches. With repetitive concussive injuries, athletes can experience permanent changes such as chronic traumatic encephalopathy (gradual degeneration of brain tissue), which can lead to personality changes and memory deficits. This literature review aims to provide insight into concussions and the evaluation of physiological changes and long-term sequelae. A comprehensive literature search was performed from April 2012 to April 2022 using PubMed/MEDLINE (Medical Literature Analysis and Retrieval System Online) and Embase databases. Nineteen articles were finally included in the literature review. The review shows that neuroimaging results demonstrated significant changes in the brain structure and function including alternations in the thalamus, hippocampus, corpus callosum, and the white matter, which can extend beyond the symptom amelioration. In addition, other approaches include brain metabolism, cerebral blood flow, and glucose utilization. Additional techniques include the evaluation of fatigue levels and the alterations in biomarkers, specifically IL-6. These approaches have demonstrated that consequences of concussions, including alternations in brain structure and function, can extend beyond an athlete's report of symptom resolution, and should be taken into consideration for return to play. The physiological changes present after a concussion have the potential to develop into long-term complications such as academic difficulty, cognitive decline, gut microbiome changes, gait changes, and increased risk of lower extremity injury. The findings in the literature review determine that is important to immediately address the symptoms of concussions to expedite treatment and prevent deleterious changes to the brain.

Decreased Concussion Incidence Following the Implementation of the Targeting Rules: An Updated Epidemiology of National Football League Concussions From 2017 to 2022

The incidence of concussions in football, and the ensuing media attention, has garnered scientific investigation, prompted technological advances in protective gear, and altered the rules of the game, including the National Football League's (NFL) "Targeting" rule, which began in 2018, but the impact of these changes is unclear. This study aims to describe the epidemiology of concussions that occurred in five NFL seasons from the 2017-2018 season through the 2021-2022 season and characterize positional differences in rate and games missed. There was a significant decrease (p = 0.02) in total concussions between the 2017-2018 season (102 concussions) and the remaining four seasons (average of 73.80 concussions per year), accounting for a 38% decrease. Offensive and defensive units had decreased concussion rates and average games missed per concussion. Defensive backs (10.46 per 1,000 athlete exposures (AEs)) and tight ends (10.69 per 1,000 AEs) had the highest concussion rates, and the defensive line had the highest average games missed per concussion at 3.97. The introduction of the "Targeting" rule and other rule changes in the NFL in 2018 correlated with a decrease in total concussions per year, total games missed due to concussion, and average games missed per concussion. Offense and defense experienced similar reductions in concussion incidence and severity. Overall, the updated epidemiology of NFL concussions suggests that the incidence of concussions has decreased; however, players continue to experience concussions that require them to miss multiple games.

Diffusion in the corpus callosum predicts persistence of clinical symptoms after mild traumatic brain injury, a multi-scanner study

Background

Mild traumatic brain injuries (mTBIs) comprise 80% of all TBI, but conventional MRI techniques are often insensitive to the subtle changes and injuries produced in a concussion. Diffusion tensor imaging (DTI) is one of the most sensitive MRI techniques for mTBI studies with outcome and symptom associations described. The corpus callosum (CC) is one of the most studied fiber tracts in TBI and mTBI, but the comprehensive post-mTBI symptom relationship has not fully been explored.

Methods

This is a retrospective observational study of how quantitative DTI data of the CC and its sub-regions may relate to clinical presentation of symptoms and timing of resolution of symptoms in patients diagnosed with uncomplicated mTBI. DTI and clinical data were obtained retrospectively from 446 (mean age 42 years, range 13-82) civilian patients. From patient medical charts, presentation of the following common post-concussive symptoms was noted: headache, balance issues, cognitive deficits, fatigue, anxiety, depression, and emotional lability. Also recorded was the time between injury and a visit to the physician when improvement or resolution of a particular symptom was reported. FA values from the total CC and 3 subregions of the CC (genu or anterior, mid body, and splenium or posterior) were obtained from hand tracing on the Olea Sphere v3.0 SP12 free-standing workstation. DTI data was obtained from 8 different 3T MRI scanners and harmonized via ComBat harmonization. The statistical models used to explore the association between regional Fractional Anisotropy (FA) values and symptom presentation and time to symptom resolution were logistic regression and interval-censored semi-parametric Cox proportional hazard models, respectively. Subgroups related to age and timing of first scan were also analyzed.

Results

Patients with the highest FA in the total CC (p = 0.01), anterior CC (p < 0.01), and mid-body CC (p = 0.03), but not the posterior CC (p = 0.91) recovered faster from post-concussive cognitive deficits. Patients with the highest FA in the posterior CC recovered faster from depression (p = 0.04) and emotional lability (p = 0.01). There was no evidence that FA in the CC or any of its sub-regions was associated with symptom presentation or with time to resolution of headache, balance issues, fatigue, or anxiety. Patients with mTBI under 40 had higher FA in the CC and the anterior and mid-body subregions (but not the posterior subregion: p = 1.00) compared to patients 40 or over (p ≤ 0.01). There was no evidence for differences in symptom presentation based on loss of consciousness (LOC) or sex (p ≥ 0.18).

Conclusion

This study suggests that FA of the CC has diagnostic and prognostic value for clinical assessment of mTBI in a large diverse civilian population, particularly in patients with cognitive symptoms.

Traumatic Brain Injury: Acupuncture Treatment

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. It is estimated that half of the people in the world will experience at least 1 episode of TBI during their lifetimes. While the primary injury to the brain parenchyma is usually irreversible, the secondary effects, which involve cellular dysfunction, derangement of blood flow, and blood-brain barrier changes in ionic flux and elevated levels of free radicals are potentially amenable to treatment. At present, there are no neuroprotective agents in mainstream medicine to interrupt these secondary processes and improve the patient's neurologic outcome. Acupuncture holds promise to fill this gap and scientific evidence to that effect is presented. Sports-related brain injury is discussed in detail.

Online youth concussion resources for Canadian teachers and school staff: A systematic search strategy

INTRODUCTION

Teachers and school staff (i.e., principals, coaches, trainers, educational assistants, guidance counselors, school healthcare professionals, etc.) are well positioned to support students' return-to-school post-concussion. Teachers and school staff may access concussion resources online as they are readily available; however, their quality and accuracy are unknown.

OBJECTIVE

To identify accurate online concussion resources suitable for Canadian teachers and school staff.

METHODS

A five-phased systematic search strategy was conducted: 1) initial identification of resources; 2) consultation of pediatric concussion experts; 3) inclusion and exclusion criteria; 4) content review; and, 5) material evaluation.

RESULTS

A total of 837 resources were identified initially and 40 resources were included in the final list. Across all resources, 310 (37%) resources were excluded as they were not designed primarily for teachers and school staff. Thirty-four (43%) of 80 resources reviewed for content accuracy were excluded. Among resources reviewed for readability, usability and suitability, six (13%) were excluded.

CONCLUSIONS

The 40 resources identified in this study can enable teachers and school staff to educate themselves about concussion and how to optimally support a student's return-to-school post-concussion.

Preliminary Observations of Personalized Repetitive Magnetic Stimulation (PrTMS) Guided by EEG Spectra for Concussion

There are no FDA-approved treatments for the chronic sequelae of concussion. Repetitive magnetic transcranial stimulation (rTMS) has been explored as a therapy but outcomes have been inconsistent. To address this we developed a personalized rTMS (PrTMS) protocol involving continual rTMS stimulus frequency adjustment and progressive activation of multiple cortical sites, guided by spectral electroencephalogram (EEG)-based analyses and psychological questionnaires. We acquired pilot clinical data for 185 symptomatic brain concussion patients who underwent the PrTMS protocol over an approximate 6 week period. The PrTMS protocol used a proprietary EEG spectral frequency algorithm to define an initial stimulation frequency based on an anteriorly graded projection of the measured occipital alpha center peak, which was then used to interpolate and adjust regional stimulation frequency according to weekly EEG spectral acquisitions. PrTMS improved concussion indices and normalized the cortical alpha band center frequency and peak EEG amplitude. This potentially reflected changed neurotransmitter, cognitive, and perceptual status. PrTMS may be a promising treatment choice for patients with persistent concussion symptoms. This clinical observational study was limited in that there was no control group and a number of variables were not recorded, such as time since injury and levels of depression. While the present observations are indeed preliminary and cursory, they may suggest further prospective research on PrTMS in concussion, and exploration of the spectral EEG as a concussion biomarker, with the ultimate goals of confirmation and determining optimal PrTMS treatment parameters.

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.

Delivering concussion education to pre-service teachers through the SCHOOLFirst website: Evaluating usability and satisfaction

BACKGROUND

Return-to-school processes indicate 'when' to initiate activities and 'what' activities should be accomplished, but are missing 'how' to implement the process. The SCHOOLFirst website provides the 'how' through building concussion knowledge, creating a supportive culture and defining roles. Due to the involvement of pre-service teachers in schools during training and imminent transition to becoming teachers, it is important that pre-service teachers are trained in concussion and can optimally support current and future students.

OBJECTIVE

To determine: 1) pre-service teachers' knowledge and confidence surrounding the return-to-school process before and after using the SCHOOLFirst website; 2) the usability, intended use and satisfaction of the SCHOOLFirst website from the perspective of pre-service teachers.

METHODS

Thirty pre-service teachers completed the demographic survey, knowledge and confidence survey, System Usability Scale, and satisfaction and intended use survey after participating in a workshop.

RESULTS

Significant increases in concussion knowledge (Z = -4.093, p <  0.001) and confidence in helping students return-to-school (Z = -4.620, p <  0.001) were measured after using the SCHOOLFirst website. Participants were satisfied with the SCHOOLFirst website (93.4%) and intend to use it in the future when supporting a student post-concussion (96.4%).

CONCLUSION

The SCHOOLFirst website is a valuable tool for pre-service teachers to support students' return-to-school post-concussion.

Epidemiological analysis of pediatric baseball and softball concussions in United States emergency departments

PURPOSE

To evaluate the epidemiology of concussions in pediatric baseball and softball players. We hypothesized that head-to-ball injuries would be the most common cause of concussions.

METHODS

The National Electronic Injury Surveillance System (NEISS) database was used to gather data. Concussions occurring during baseball and softball participation in pediatric patients (4-17 years old) from 2012 to 2021 was gathered. Concussion mechanisms were grouped into 5 categories: head-to-player, head-to-ball, head-to-surface (ground, walls, railings), head-to-bat, and unknown. Linear regression models were used to assess changes in yearly concussion rates over the study period. Results from these models were reported using parameter estimates and the estimated Pearson correlation coefficient.

RESULTS

A weighted total of 54,978 baseball and softball related concussion injuries were analyzed. The average weighted age of our cohort at the time of injury was 13.1 years, with 54.1% (n = 29,761) of concussions occurring in males. The national estimated incidence of concussion injuries decreased non-significantly over the study period (slope estimate = -311 concussions/year, r = -0.625, p-value = 0.054). The majority of weighted national estimate concussions were due to head-to-ball injuries (n = 34,650; 63.0%), followed by head-to-player (n = 8501; 15.5%), head-to-surface (n = 5347; 9.7%), and head-to-bat (n = 5089; 9.3%). On sub-analysis, individuals were grouped into 3 age brackets: 4-8, 9-13, and 14-17 years. The most common mechanism of concussions in children of all ages was head-to-ball. The incidence of head-to-player and head-to-surface injuries increased throughout each age group, while head-to-bat decreased.

CONCLUSION

The incidence of concussions in pediatric baseball and softball athletes has been decreasing non-significantly over our 10-year study period. The most common mechanism of concussions in our study was head-to-ball injuries.

Epidemiological analysis of concussions in youth ice hockey players: A national emergency room database study

PURPOSE

To evaluate the epidemiology of concussions in youth ice hockey players.

METHODS

The National Electronic Injury Surveillance System (NEISS) database was used to gather data. Concussions occurring during ice hockey participation in youth patients (4-21 years old) from 2012 to 2021 was gathered. Concussion mechanisms were grouped into 7 categories: head-to-player, head-to-puck, head-to-ice, head-to-board/glass, head-to-stick, head-to-goal post, and unknown. Hospitalization rates were also tabulated. Linear regression models were used to assess changes in yearly concussion and hospitalization rates over the study period. Results from these models were reported using parameter estimates [with 95% confidence intervals (CI)] and the estimated Pearson correlation coefficient. Additionally, logistic regression was used to model the risk of hospitalization across the different cause categories.

RESULTS

A total of 819 ice hockey related concussions were analyzed between 2012 and 2021. The average age of our cohort was 13.4 years, with 89.3% (n = 731) of concussions occurring in males. The incidence of head-to-ice, head-to-board/glass, head-to-player, and head-to-puck concussion mechanisms decreased significantly over the study period (slope estimate = -2.1 concussions/year [CI: (-3.9, -0.2)], r = -0.675, p = 0.032), (slope estimate = -2.7 concussions/year [CI: (-4.3, -1.2)], r = -0.816, p = 0.004), (slope estimate = -2.2 concussions/year [CI: (-3.4, -1.0)], r = -0.832, p = 0.003), and (slope estimate = -0.4 concussions/year [CI: (-0.62, -0.09)], r = -0.768, p = 0.016), respectively. Majority of patients were discharged from the emergency department (ED) to their home, as only 20 people (2.4%) were hospitalized over our study period. The majority of concussions were due to head-to-ice (n = 285, 34.8%), followed by head-to-board/glass (n = 217, 26.5%) and head-to-player (n = 207, 25.3%). The most common cause for hospitalizations due to concussions was head-to-board/glass (n = 7, 35%), followed by head-to-player (n = 6, 30%) and head-to-ice (n = 5, 25%).

CONCLUSION

The most common mechanism of youth ice hockey concussions was head-to-ice in our 10-year study period, while head-to-board/glass was the most common cause of hospitalizations. IRB: This project did not require review by the institutional review board.

Clinical gait characteristics in the early post-concussion phase: A systematic review

BACKGROUND

Understanding gait alterations immediately post-concussion can improve identification, management and prognosis of concussion.

OBJECTIVE

To identify and define gait characteristics immediately post-concussion.

METHOD

A review of electronic databases was conducted using terms gait alteration AND mTBI OR concussion. 172 reports were identified. After restricting to English and human studies, 158 remained. Reports were screened to include studies assessing quantifiable gait change post-concussion. 12 studies were included.

DISCUSSION

Multiple gait features are altered post-impact: stability, step length, walking speed and postural control. There is evidence that postural measures in gait initiation and termination may identify more subtle deficits. There is paucity of data evaluating the impact of concussion on gait function acutely and the authors identified no studies examining immediate changes.

CONCLUSION

Acutely post-concussion, various gait alterations are seen and correlate with degree of deficit and prognosis. Slowed gait, instability and postural control are several features. Dynamic gait and postural assessments identify more subtle gait alterations. Given the absence in literature, high quality prospective studies examining immediate gait alterations post-concussion would contribute to improved assessment, management and prognostication. Given difficulty in participant recruitment, technological and standardised gait assessments should be used to assess force of impact and immediate gait alteration.

Regional variances depict a unique glial-specific inflammatory response following closed-head injury

Mild traumatic brain injuries (mTBI) constitute a significant health concern with clinical symptoms ranging from headaches to cognitive deficits. Despite the myriad of symptoms commonly reported following this injury, there is still a lack of knowledge on the various pathophysiological changes that occur. Preclinical studies are at the forefront of discovery delineating the changes that occur within this heterogeneous injury, with the emergence of translational models such as closed-head impact models allowing for further exploration of this injury mechanism. In the current study, male rats were subjected to a closed-head controlled cortical impact (cCCI), producing a concussion (mTBI). The pathological effects of this injury were then evaluated using immunoflourescence seven days following. The results exhibited a unique glial-specific inflammatory response, with both the ipsilateral and contralateral sides of the cortex and hippocampus showing pathological changes following impact. Overall these findings are consistent with glial changes reported following concussions and may contribute to subsequent symptoms.

Head Injuries in Rock Climbing: A Scoping Review

Rock climbing was recognized as a sport at the 2020 Tokyo Olympics. Despite its increasing participation, there is no knowledge synthesis of head injuries (HIs), defined as any injury to the head, associated with climbing, making it challenging for clinicians to provide evidence-based care. Our aim was to synthesize HI literature within rock climbing and identify knowledge gaps. Six databases (Medline, Embase, Sports Medicine & Education Index, SPORTDiscus, CINAHL, and Cochrane) were searched. Two reviewers screened 345 studies and 31 studies were selected for data abstraction. We found the quality of individual studies mainly "fair" to "good." Both HI and traumatic brain injury (TBI) had inconsistent definitions and categorization. The HIs represented between 0 to 36% of reported climbing injuries. Between 11 to 100% of HIs were TBIs, defined as an HI with permanent or temporary neurological sequelae. The most common causes of HIs were outdoor falls and falling objects. Climbing-specific factors associated with the causes were infrequently examined in the literature. Data sources of safety practices were incomplete. Overall, there was a lack of literature examining HIs, mechanisms of injury, and safety practices associated with climbing. To improve the tracking of HIs in climbing, we suggest the use of consistent reporting standards and the creation of a climbing injury surveillance system.

Misdiagnosis of Pediatric Concussions in the Emergency Department: A Retrospective Study

OBJECTIVE

We aimed to determine the rate and predictors of correctly diagnosed concussions in the pediatric emergency department and to describe the characteristics, presentation, and management of concussions in children presenting for minor head injury.

METHODS

We included 186 patients aged 5 to 18 years presenting within 24 hours of minor head injuries and met our diagnostic criteria for concussion. We compared patients correctly diagnosed with a concussion with those who were not. Our main outcome was the rate and predictors of misdiagnoses.

RESULTS

Of the patients, 5.4% were correctly diagnosed. Amnesia was the only variable associated with correct diagnoses (40.0% vs 10.2%, P = 0.02). The most common mechanism of injury was fall (8.4%); the most frequent symptoms were nausea/vomiting (42.5%), and 48.4% had a brain computed tomography scan done.

CONCLUSIONS

The high rate of concussion misdiagnosis puts into question the usability of current concussion guidelines, their accuracy, and barriers to translation into clinical practice.

A deep learning-based approach to diagnose mild traumatic brain injury using audio classification

Mild traumatic brain injury (mTBI or concussion) is receiving increased attention due to the incidence in contact sports and limitations with subjective (pen and paper) diagnostic approaches. If an mTBI is undiagnosed and the athlete prematurely returns to play, it can result in serious short-term and/or long-term health complications. This demonstrates the importance of providing more reliable mTBI diagnostic tools to mitigate misdiagnosis. Accordingly, there is a need to develop reliable and efficient objective approaches with computationally robust diagnostic methods. Here in this pilot study, we propose the extraction of Mel Frequency Cepstral Coefficient (MFCC) features from audio recordings of speech that were collected from athletes engaging in rugby union who were diagnosed with an mTBI or not. These features were trained on our novel particle swarm optimised (PSO) bidirectional long short-term memory attention (Bi-LSTM-A) deep learning model. Little-to-no overfitting occurred during the training process, indicating strong reliability of the approach regarding the current test dataset classification results and future test data. Sensitivity and specificity to distinguish those with an mTBI were 94.7% and 86.2%, respectively, with an AUROC score of 0.904. This indicates a strong potential for the deep learning approach, with future improvements in classification results relying on more participant data and further innovations to the Bi-LSTM-A model to fully establish this approach as a pragmatic mTBI diagnostic tool.

Assessing Cognitive Behavioral Therapy for Insomnia to Improve Sleep Outcomes in Individuals With a Concussion: Protocol for a Delayed Randomized Controlled Trial

BACKGROUND

Sleep disturbances post concussion have been associated with more frequent and severe concussion symptoms and may contribute to poorer recovery. Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment for insomnia; however, it remains unclear if this treatment method is effective in improving sleep outcomes and reducing concomitant postconcussion symptoms.

OBJECTIVE

The hypotheses for this study are that (1) CBT-I will improve sleep outcomes and (2) CBT-I will improve concomitant postconcussion symptoms.

METHODS

In total, 40 individuals who are within ≥4 weeks of postconcussion injury and have insomnia symptoms will be enrolled in this randomized controlled trial. Participants will be randomized into either a group that starts a 6-week CBT-I program immediately after baseline or a waitlist control group that starts CBT-I following a 6-week waiting period. All participants will be reassessed 6, 12, and 18 weeks after baseline. Standardized assessments measuring sleep outcomes, postconcussion symptoms, and mood will be used. Linear regression and t tests will be used for statistical analyses.

RESULTS

Enrollment of 40 participants was completed July 2022, data collection will be completed in November 2022, and publication of main findings is anticipated in May 2023. It is anticipated that participants experience reduced insomnia symptoms and postconcussion symptoms following CBT-I and these improvements will be retained for at least 12 weeks. Additionally, we expect to observe a positive correlation between sleep and postconcussion symptom improvement.

CONCLUSIONS

Successful completion of this pilot study will allow for a better understanding of the treatment of insomnia and postconcussion symptoms in individuals following a concussion.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04885205; https://clinicaltrials.gov/ct2/show/NCT04885205.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/38608.

A non-invasive biomechanical model of mild TBI in larval zebrafish

A mild traumatic brain injury is a neurological dysfunction caused by biomechanical forces transmitted to the brain in physical impacts. The current understanding of the neuropathological cascade resulting in the manifested clinical signs and symptoms is limited due to the absence of sensitive brain imaging methods. Zebrafish are established models for the reproduction and study of neurobiological pathologies. However, all available models mostly recreate moderate-to-severe focal injuries in adult zebrafish. The present work has induced a mild brain trauma in larval zebrafish through a non-invasive biomechanical approach. A custom-made apparatus with a commercially available motor was employed to expose larvae to rapidly decelerating linear movements. The neurophysiological changes following concussion were assessed through behavioural quantifications of startle reflex locomotor distance and habituation metrics. Here we show that the injury was followed, within five minutes, by a transient anxiety state and CNS dysfunction manifested by increased startle responsivity with impaired startle habituation, putatively mirroring the human clinical sign of hypersensitivity to noise. Within a day after the injury, chronic effects arose, as evidenced by an overall reduced responsivity to sensory stimulation (lower amplitude and distance travelled along successive stimuli), reflecting the human post-concussive symptomatology. This study represents a step forward towards the establishment of a parsimonious (simple, less ethically concerning, yet sensitive) animal model of mild TBI. Our behavioural findings mimic aspects of acute and chronic effects of human concussion, which warrant further study at molecular, cellular and circuit levels. While our model opens wide avenues for studying the underlying cellular and molecular pathomechanisms, it also enables high-throughput testing of therapeutic interventions to accelerate post-concussive recovery.

Effect of the COVID-19 Pandemic on Sports-Related Injuries Evaluated in US Emergency Departments

Background:

Organized athletics are undergoing a gradual resumption after a prolonged hiatus in 2020 because of the coronavirus disease 2019 (COVID-19) pandemic.

Purpose/Hypothesis:

The purpose of this study was to evaluate the effect of the 2020 COVID-19 period on emergency department (ED) visits for sports-related injuries in the United States. It was hypothesized that such visits decreased in response to the pandemic conditions.

Study Design:

Descriptive epidemiology study.

Methods:

A selection of sports (baseball, basketball, softball, soccer, American football, weightlifting, track and field, martial arts, boxing, golf, personal fitness, cycling, tennis, and ice hockey) were classified as being an organized team, organized individual, or nonorganized sport. The National Electronic Injury Surveillance System database was then queried for ED visits for sports-related injuries between January 1, 2018, and December 31, 2020, and we compared weighted national injury estimates and injury characteristics from athletes presenting to EDs in 2018 and 2019 versus those from the 2020 COVID-19 pandemic period and between March 1 and May 31, 2020 (government-imposed lockdown period). Bivariate comparisons between variables were conducted using chi-square analysis, with strength of association assessed using odds ratios.

Results:

The 164,151 unweighted cases obtained from the query resulted in a weighted national estimate of 5,664,795 sports-related injuries during the study period. Overall, there was a 34.6% decrease in sports-related ED visits in 2020 compared with the yearly average between 2018 and 2019 (baseline). The number of ED visits in 2020 decreased by 53.9% versus baseline for injuries incurred by participation in an organized team sport and by 34.9% for injuries incurred by participation in an organized individual sport. The number of ED visits during the 2020 lockdown period decreased by 76.9% versus baseline for injuries incurred by participation in an organized team sport and by 65.8% for injuries incurred by participation in an organized individual sport. Injuries sustained while participating in a nonorganized sport remained relatively unaffected and decreased by only 8.1% in 2020.

Conclusion:

ED visits in the United States for injuries sustained while participating in an organized team or individual sport underwent a decrease after the beginning of the COVID-19 pandemic in 2020, especially during the lockdown period.

Diffusion and functional MRI findings and their relationship to behaviour in postconcussion syndrome: a scoping review

Postconcussion syndrome (PCS) is a term attributed to the constellation of symptoms that fail to recover after a concussion. PCS is associated with a variety of symptoms such as headaches, concentration deficits, fatigue, depression and anxiety that have an enormous impact on patients' lives. There is currently no diagnostic biomarker for PCS. There have been attempts at identifying structural and functional brain changes in patients with PCS, using diffusion tensor imaging (DTI) and functional MRI (fMRI), respectively, and relate them to specific PCS symptoms. In this scoping review, we appraised, synthesised and summarised all empirical studies that (1) investigated structural or functional brain changes in PCS using DTI or fMRI, respectively, and (2) assessed behavioural alterations in patients with PCS. We performed a literature search in MEDLINE (Ovid), Embase (Ovid) and PsycINFO (Ovid) for primary research articles published up to February 2020. We identified 8306 articles and included 45 articles that investigated the relationship between DTI and fMRI parameters and behavioural changes in patients with PCS: 20 diffusion, 20 fMRI studies and 5 papers with both modalities. Most frequently studied structures were the corpus callosum, superior longitudinal fasciculus in diffusion and the dorsolateral prefrontal cortex and default mode network in the fMRI literature. Although some white matter and fMRI changes were correlated with cognitive or neuropsychiatric symptoms, there were no consistent, converging findings on the relationship between neuroimaging abnormalities and behavioural changes which could be largely due to the complex and heterogeneous presentation of PCS. Furthermore, the heterogeneity of symptoms in PCS may preclude discovery of one biomarker for all patients. Further research should take advantage of multimodal neuroimaging to better understand the brain-behaviour relationship, with a focus on individual differences rather than on group comparisons.

Improving Outcomes for Work-Related Concussions: A Mental Health Screening and Brief Therapy Model

OBJECTIVE

This study assessed the efficacy of a neurocognitive screening evaluation and brief therapy model to improve RTW outcomes for workers who experienced mild head injuries.

METHODS

Patients referred were evaluated using a neurocognitive and psychological screening battery. Work-focused cognitive behavioral therapy was provided when appropriate, addressing the role of negative emotional adjustment and functional sleep disturbance in prolonging recovery.

RESULTS

Average time to RTW was 7 weeks post-evaluation, despite workers being off an average of 10 months between injury and referral dates. Overall, 99% were released to full-duty work without restrictions or accommodations.

CONCLUSIONS

This study demonstrates the favorable outcomes achieved via a structured, clinically driven program for workers who experience head-involved injuries, validating previous research on the importance of recognizing the role of psychological factors in prolonging concussion recovery.

Evidence of altered interhemispheric communication after pediatric concussion

OBJECTIVES: To investigate neurophysiological alterations within the typical symptomatic period after concussion (1-month) and throughout recovery (6-months) in adolescents; and (2) to examine relationships between neurophysiological and upper limb kinematic outcomes.METHODS: 18 adolescents with concussion were compared to 17 healthy controls. Transcranial magnetic stimulation (TMS) was used to assess neurophysiological differences between groups including: short- and long-interval intracortical inhibition, intracortical facilitation, short- and long-latency afferent inhibition, afferent facilitation, and transcallosal inhibition (TCI). Behavioral measures of upper limb kinematics were assessed with a robotic device.RESULTS: Mixed model analysis of neurophysiological data identified two key findings. First, participants with concussion demonstrated delayed onset of interhemispheric inhibition, as indexed by TCI, compared to healthy controls. Second, our exploratory analysis indicated that the magnitude of TCI onset delay in adolescents with concussion was related to upper limb kinematics.CONCLUSIONS: Our findings indicate that concussion in adolescence alters interhemispheric communication. We note relationships between neurophysiological and kinematic data, suggesting an affinity for individuals with less concussion-related physiological change to improve their motor behavior over time. These data serve as an important step in future development of assessments (neurobiological and clinical) and interventions for concussion.

Exploring the Severity of Craniomaxillofacial Injuries From Horseback Riding

PURPOSE

The purpose of our study is to assess the severity of craniomaxillofacial injuries from horseback-riding accidents.

MATERIALS AND METHODS

This is a 20-year retrospective cross-sectional study of the National Electronic Injury Surveillance System. Injuries from the activity of horseback-riding were included if they occurred in the craniomaxillofacial complex. Study predictors were derived from both patient and injury characteristics. The study outcome was the presence or absence (probability) of hospital admission from the emergency department. A multiple logistic regression model was created to model the odds of admission using all significant univariate predictors.

RESULTS

The final sample consisted of 6730 patients. The decrease in horseback riding injuries from 2000 to 2019 was significant (P = 0.042).The mean age of the sample was 27.80 years (range: 2-91 years). Gender-wise, females composed the majority of injured horseback riders (71.9%). Over two-thirds of the sample consisted of White patients (68.1%). Over three-fourths of the injuries occurred in the head (80.9%), rendering it the most frequently injured region of the craniomaxillofacial complex. The most common primary diagnoses were internal organ injury (40.2%). On univariate analysis, the admission rates were significantly associated with gender (P < 0.01), age group (P < 0.01), body part injured (P < 0.01), diagnosis (P < 0.01), location of injury (P < 0.01) and mechanism of injury (P < 0.05). Relative to young adults, children (odds ratio [OR], 1.579; 95% OR confidence interval [CI] [1.31, 1.91]; P < 0.01), adults (OR, 1.857; 95% OR CI [1.55, 2.22]; P < 0.01), and seniors (OR, 3.738; 95% OR CI [2.73, 5.12]; P < 0.01) were each independently associated with an increased odds of admission. Relative to the mouth, the head had 4.8 odds of admission (P < 0.01) and the face had 2.5 odds of admission (P < 0.01). Relative to contusions/abrasion, concussions (OR, 3.542; 95% OR CI [2.28, 5.49]; P < 0.01) and internal organ injuries (OR, 9.020; 95% OR CI [5.90, 13.79]; P < 0.01), lacerations (OR, 1.946; 95% OR CI [1.17, 3.24]; P < 0.05), and fractures (OR, 32.068; 95% OR CI [20.53, 50.09]; P < 0.01) were each independently associated with increased odds of admission relative to contusions. Direct trauma from a horse (OR, 1.422; 95% OR CI [1.06, 1.91]; P < 0.05) was associated with independently increased odds of admission relative to other injuries. Injuries that took place in a farm (OR, 1.617; 95% OR CI [1.25, 2.09]; P < 0.01) and a street (OR, 2.735; 95% OR CI [1.83, 4.09]; P < 0.01) were each independently associated with increased odds of admission. Finally, relative to females, males (OR, 1.374; 95% OR CI [1.20, 1.57]; P < 0.01) were independently associated with increased odds of admission.

CONCLUSIONS

Many variables contribute to the chance of hospital admission from horseback riding. Fractures seem to be the leading risk factor for hospital admission, therefore, future study may look into how to reduce the incidence of fractures through the employment of more protective equipment than helmets for horseback riders.

Sleep quality in the chronic stage of concussion is associated with poorer recovery: A systematic review

Background

Recovery from a concussion varies based on a multitude of factors. One such factor is sleep disturbances. In our prior review, it was observed that in the acute phase, sleep disturbances are predictive of poor outcomes following a concussion. The literature gap remains on how sleep in the chronic phase of recovery affects outcomes.

Objective

To examine the association between sleep quality during the chronic stage of concussion and post-concussion outcomes. Literature Survey: Literature searches were performed during 1 July to 1 August 2019 in selected databases along with searching grey literature. Out of the 733 results, 702 references were reviewed after duplicate removal.

Methods

Three reviewers independently reviewed and consented on abstracts meeting eligibility criteria ( n = 35). The full-text articles were assessed independently by two reviewers. Consensus was achieved, leaving four articles. Relevant data from each study was extracted using a standard data-extraction table. Quality appraisal was conducted to assess potential bias and the quality of articles.

Results

One study included children (18–60 months) and three studies included adolescents and/or adults (ranging 12–35 years). The association between sleep and cognition (two studies), physical activity (one study), and emotion symptoms (one study) was examined. Sleep quality was associated with decreased cognition and emotional symptoms, but not with meeting physical activity guidelines six months post-concussion injury.

Conclusions

The heterogeneity in age of participants and outcomes across studies and limited number of included studies made interpretations difficult. Future studies may consider if addressing sleep quality following concussion will improve outcomes.

Engaging target users to appraise and refine clinical practice guidelines in pediatric concussion: An integrated knowledge translation approach

Background

Clinical practice guidelines are systematically developed statements that assist clinicians in making evidence informed decisions regarding patient care. Within pediatric concussion, the Ontario Neurotrauma Foundation released the Guidelines for Diagnosing and Managing Pediatric Concussion in 2014. The purpose of this study was to evaluate the 2014 guidelines using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) evaluation tool, in addition to a brief knowledge translation survey, and to utilize the collected feedback from end users to inform improvements to support an updated version. An integrated knowledge translation approach was employed using clinical experts as guideline appraisers.

Methods

A purposive sample of researchers, physicians, allied health professionals, policy makers, educators and knowledge translation experts involved in updating the guidelines (N = 31) completed the AGREE II Likert scale survey regarding the 2014 guideline, and provided written justifications for their ratings. Domain and item AGREE II scaled scores were reported stratified by demographic factors, and written justifications were synthesized using content analysis to determine areas of improvement for the 2014 guideline.

Results

Appraisers scored the editorial independence (88.9%) and scope and purpose (80.8%) domains the highest, indicating high quality. The guidelines scored the lowest in the applicability domain (69.3%). Participants with less than 10 years of experience in their respective disciplines, as well as physicians and allied health professionals consistently provided higher ratings across domains compared to other professions.

Conclusions

The process of evaluating the 2014 guideline resulted in these important outcomes: (1) identified areas of the guideline that may have affected the lack of previous clinical uptake while abiding by a clinical practice guideline development framework; (2) shared and informed decision making regarding content and format of the revised clinical practice guideline; and (3) targeted content, clinical questions and dissemination strategies, which are key to clinical uptake.

Long-Term Impact of Mild Traumatic Brain Injuries on Multiple Functional Outcomes and Epigenetics: A Pilot Study with College Students

People who suffer a mild traumatic brain injury (mTBI) have heterogeneous symptoms and disease trajectories, which make it difficult to precisely assess long-term complications. This pilot study assessed and compared deficits in cognitive, psychosocial, visual functions, and balance performance between college students with and without histories of mTBI. Global DNA methylation ratio (5-mC%) in blood was also compared as a peripheral epigenetic marker. Twenty-five volunteers participated, including 14 healthy controls (64.3% females; mean age of 22.0) and 11 mTBI cases (27.3% females; mean age of 28.7 years) who self-reported mTBI history (63.6% multiple; 2.5 ± 1.29 injuries) with 7.1 years on average elapsed following the last injury. Every participant was assessed for cognitive (executive function, memory, and processing speed), psychological (depression, anxiety, and sleep disturbances), and visual function (by King–Devick and binocular accommodative tests); force-plate postural balance performance; and blood 5-mC% levels. Students with mTBI showed poorer episodic memory, severe anxiety, and higher blood 5-mC% ratio, compared to controls (all p’s < 0.05), which were still significant after adjusting for age. No differences were detected in sleep problems (after adjusting for age), visual function, and postural balance. These findings identified changes in multiple functions and peripheral epigenetics long after mTBI.

Delayed Symptom Onset Following Pediatric Sport-Related Concussion

Objective: (1) To examine the prevalence of delayed symptom onset (DSO) among pediatric sport-related concussion (SRC) patients as well as the effect of symptom onset on initial symptom severity, length of recovery, and development of delayed recovery; (2) to evaluate the impact of symptom onset on sideline management.

Methods: We conducted a prospective study of pediatric SRC patients (<20 years of age) evaluated at a multi-disciplinary concussion program. Patients underwent initial medical assessment by a single neurosurgeon and a structured interview by a research assistant. Patients were classified as experiencing early symptom onset (symptom onset <15 min from the time of the suspected injury; ESO) or DSO (≥15 min from the time of the suspected injury).

Results: A total of 144 SRC patients (61.1% male; mean age 14.6 years, SD 1.8) evaluated a median of 5.0 days (IQR 4.0, 9.0) post-injury were included in the study. Among these patients, 120 (83.3%) reported experiencing ESO while 24 (16.7%) experienced DSO following injury. Among those that experienced DSO the median length of time from the suspected injury to symptom onset was 60.0 min (IQR 20.0, 720.0). No significant differences were observed in symptom severity at initial medical assessment (median Post-Concussion Symptom Scale score 20.0 vs. 18.0, p = 0.35), length of physician-document clinical recovery (median 22.0 vs. 24.0 days; p = 0.46) or the proportion of those who developed delayed physician-documented clinical recovery (34.4 vs. 42.1%, p = 0.52) among patients with ESO or DSO. Patients who reported experiencing ESO were significantly more likely to be immediately removed from play at the time of their suspected injury compared to those who experienced DSO (71.6% vs. 29.2%; p < 0.0001).

Conclusions: This study suggests that an important proportion of children and adolescents who sustain an acute SRC experience DSO. DSO is associated with lower rates of immediate removal from play at the time of suspected injury. Secondary study findings highlight the need for improved sport stakeholder concussion education and standardized concussion protocols that mandate the immediate and permanent removal of all youth with a suspected concussion until they undergo medical assessment.

Bicycling-related concussions leading to postconcussion syndrome in adults

Background

Concussions among adult bicyclists are common, but little is known about the long-term effects of the consequences of these concussions such as postconcussion syndrome (PCS) including its occurrence, clinical features and recovery potential. Indeed, our study is the first to examine PCS due to bicycling in any age group.

Objectives

We examined patient demographics, concussion mechanisms and persistent symptoms as factors leading to PCS in adults and the potential for recovery.

Methods

We conducted a retrospective chart review of 28 patients age 18 or older who sustained a concussion while bicycling and were referred to the Canadian Concussion Centre for management of PCS.

Results

Eighteen patients (64.3%) fell from their bicycles due to loss of control, attempts to avoid a crash or collision with an object. Eight patients (28.6%) were struck by a motor vehicle, and two patients (7.1%) were injured by collision with another bicycle. The mean duration of PCS was 23.7 months and at the time of the last follow-up, 23 (82.1%) patients had failed to recover completely. Patients with one or more previous concussions had a significantly longer duration of PCS (p=0.042). Bicycling concussions resulted in a greater mean duration of PCS (23.7 months) than a comparison group of patients with PCS due to collision sports (16.1 months) (p=0.07).

Conclusion

Adults who sustain bicycling-related concussions and develop PCS often have long-lasting symptoms; greater attention should be given to prevention strategies such as improved bicycling infrastructure and safer bicycling practices to reduce concussions in adult bicyclists.

Effect of a Concussion on Anterior Cruciate Ligament Injury Risk in a General Population

BACKGROUND

Recent studies indicate concussion increases risk of musculoskeletal injury in specific groups of patients. The purpose of this study was to determine the odds of anterior cruciate ligament (ACL) injury after concussion in a population-based cohort.

METHODS

International Classification of Diseases, 9th and 10th Revision (ICD-9, ICD-10) codes relevant to the diagnosis and treatment of a concussion and ACL tear were utilized to search the Rochester Epidemiology Project (REP) between 2000 and 2017. A total of 1653 unique patients with acute, isolated ACL tears were identified. Medical records for cases were reviewed to confirm ACL tear diagnosis and to determine history of concussion within 3 years prior to the ACL injury. Cases were matched by age, sex, and REP availability date to patients without an ACL tear (1:3 match), resulting in 4959 controls. The medical records of the matched control patients were reviewed to determine history of concussion.

RESULTS

39 patients with a concussion suffered an ACL injury up to 3 years after the concussion. The rate of prior concussion was higher in ACL-injured cases (2.4%) compared to matched controls with no ACL injury (1.5%). This corresponds to an odds ratio of 1.6 (95% CI 1.1-2.4; p = 0.015).

CONCLUSIONS

Although activity level could not be assessed, there are increased odds of ACL injury after concussion in a general population. Based on the evidence of increased odds of musculoskeletal injury after concussion, standard clinical assessments should consider concussion symptom resolution as well as assessment of neuromuscular factors associated with risk of injuries.

A Nonliquid Crystal Display Screen Computer for Treatment of Photosensitivity and Computer Screen Intolerance in Post-Concussion Syndrome

Liquid crystal display (LCD) screens refresh at a rate of 60 times per second, which can be perceived by concussed individuals who have photosensitivity, leading to computer intolerance. A non-LCD computer screen that refreshes at a much lower rate could relieve this photosensitivity and computer screen intolerance in patients with post-concussion syndrome (PCS). Twenty-nine patients with PCS, computer intolerance, and photosensitivity performed a reading task for a maximum of 30 min, with an LCD computer or a non-LCD device, and were given a comprehension test after completion of the reading task. The Sport Concussion Assessment Tool 3 was administered before and after each reading task. Symptom scores, amount of time spent reading, and performance on the comprehension tests were compared between the two devices. Patients also completed a self-report questionnaire of their subjective experience. The LCD screen computer produced significantly greater symptom exacerbation (median difference = 5, W = 315, p < 0.01) and a greater number of symptoms (median difference = 1, W = 148, p < 0.01) than the non-LCD screens. The non-LCD screen resulted in a longer symptom-free reading time (median = 48 sec, W = 147, p < 0.01), but not a greater number of words read (median = 281, W = 148, p = 0.098). Females were more likely to have greater symptom exacerbation with the LCD screen (U = 14.0, p < 0.01). No significant difference was found in performance on the comprehension test. Subjective reports showed that the non-LCD experience was more favorable, and most patients stated they would recommend this device for other patients with PCS. This study is the first to show the clinical utility of non-LCD screen computers in the management of photosensitivity and computer screen intolerance in patients with PCS. The non-LCD screen computer has the potential to facilitate return-to-work or return-to-school in concussed individuals.

Recommendations for the Emergency Department Prevention of Sport-Related Concussion

Sport-related concussion refers to the subset of concussive injuries occurring during sport activities. Similar to concussion from nonsport mechanisms, sport-related concussion is associated with significant morbidity, including migrainous headaches, disruption in normal daily activities, and long-term depression and cognitive deficits. Unlike nonsport concussions, sport-related concussion may be uniquely amenable to prevention efforts to mitigate these problems. The emergency department (ED) visit for sport-related concussion represents an opportunity to reduce morbidity by timely diagnosis and management using best practices, and through education and counseling to prevent a subsequent sport-related concussion. This article provides recommendations to reduce sport-related concussion disability through primary, secondary, and tertiary preventive strategies enacted during the ED visit. Although many recommendations have a solid evidence base, several research gaps remain. The overarching goal of improving sport-related concussion outcome through enactment of ED-based prevention strategies needs to be explicitly studied.

Prevention of Concussion

Concussion is a common pediatric problem, and the best point of intervention would be to prevent a concussion from occurring. Unfortunately, information in this area has inconsistent support for the various methods that have been attempted. In infants, concussions are typically related to safety hazards in the environment and attempts to make the environment safer have resulted in decreased injuries over time. Toddlers also face environmental hazards that are slightly different in light of their increased mobility. School-aged children and adolescents primarily sustain concussions in the course of participation in organized contact sports. Although much research has been devoted to protective equipment, there is not a clearly effective piece of equipment that prevents concussions. Some effect has been demonstrated with changes in rules and policy that limit or eliminate certain kinds of dangerous contact. Research is still being performed to adequately evaluate methods that are already being used, as well as to find new methods in the future that may help protect today's children from concussions.

An Evidence-Based Care Model for Workers With Concussion

OBJECTIVE

To evaluate the impact of an evidence-based assessment program for people with workers' compensation claims for concussion on healthcare utilization and duration of lost time from work.

SETTING

An assessment program for people with a work-related concussion was introduced to provide physician assessment focused on education and appropriate triage.

PARTICIPANTS

A total of 3865 people with accepted workers' compensation claims for concussion with dates of injury between January 1, 2014, and February 28, 2017.

DESIGN

A quasiexperimental pre-/poststudy of healthcare utilization (measured by healthcare costs) and duration of time off work (measured by loss of earnings benefits) in a cohort of people with workers' compensation claims for concussion in the period prior to and following introduction of a new assessment program. Administrative data were retrospectively analyzed to compare outcomes in patients from the preassessment program implementation period to those in the postimplementation period.

RESULTS

The assessment program resulted in reduced healthcare utilization reflected by a 14.4% (95% confidence interval, -28.7% to -0.8%) decrease in healthcare costs. The greatest decrease in healthcare costs was for assessment services (-27.9%) followed by diagnostic services (-25.7%). There was no significant difference in time off work as measured by loss-of-earnings benefits.

CONCLUSION

A care model for people with a work-related concussion involving an evidence-based assessment by a single physician focused on patient education resulted in significantly decreased healthcare utilization without increasing duration of time off work.

Primary care management of concussion in Canada

Concussion has emerged as an important public health issue affecting thousands of Canadians annually. Health care providers including paediatricians, family and emergency medicine physicians, nurses, and nurse practitioners are commonly tasked with the responsibility of providing primary care to patients with acute concussion and those with persistent post-concussion symptoms. In July 2017, Parachute, in collaboration with the Public Health Agency of Canada and Sport Canada released the Canadian Guideline on Concussion in Sport that outlines a standardized and evidence-based approach to the recognition, diagnosis, and management of youth and adults with suspected concussion. In this report, we provide a brief overview of the important roles of primary care providers in the medical assessment, management, and prevention of concussion as outlined in this national best practice guideline.

Research on the changes in balance motion behavior and learning, as well as memory abilities of rats with multiple cerebral concussion-induced chronic traumatic encephalopathy and the underlying mechanism

To study the effects of multiple cerebral concussion (MCC)-induced chronic traumatic encephalopathy on balance motion behavior learning and memory abilities of rats and its possible mechanism. 4MCC rat models were established by means of striking the head (4MCC group, n=15), while normal Sprague-Dawley (SD) rats were used as controls (C group, n=15). At 2 weeks after injury, balance beam (BB) test, beam walking (BW) test and Morris water maze (MWM) test were performed, respectively. The metabolites in brain tissues of rats, the number of glial fibrillary acidic protein (GFAP)-positive cells and apoptotic cells in brain slices of rats, and the expression levels of phosphorylated tau (p-tau) and Aβ_1-40 proteins were detected. The score of rats in 4MCC group was significantly lower than that in C group (p<0.01). The escape latencies of rats in 4MCC group on the 4th-7th days during training and the time reaching the platform were significantly longer (p<0.05), but the residence time in the target quadrant was obviously shorter (p<0.01). Naphthalene acetic acid (NAA) and creatinine (Cr) values in septal coronal section in 4MCC group were significantly lower, but choline (Cho) and myo-inositol (MI) values were obviously higher (p<0.01). The number of GFAP-positive cells in the hippocampal and septal areas in 4MCC group were significantly larger (p<0.01). In the hippocampal and septal areas of 4MCC group, the number of apoptotic cells was obviously larger (p<0.01), and the expression levels of p-tau and Aβ_1-40 proteins were significantly higher (p<0.01). Thus, MCC-induced chronic traumatic encephalopathy can increase the expressions of p-tau and Aβ_1-40 proteins in the hippocampal and septal areas, leading to damage of hippocampal and septal neurons and increasing the number of astrocytes in the hippocampal and septal areas, ultimately damaging the balance motion behavior and learning, as well as memory abilities of rats.

Rates of concussions and minor head injuries in Quebec, 2003 and 2016, in children under 18 years old, and comparisons with Ontario's rates of mild traumatic brain injuries

OBJECTIVES

Increases of mild traumatic brain injuries in children have been reported in the USA and Ontario over the past decade. The main objective of this study is to calculate the pediatric rates of mild traumatic brain injury in Quebec, and our second objective is to compare them with those in Ontario.

METHODS

Analysts from the Régie de l'Assurance Maladie du Québec (RAMQ, Quebec Health Insurance Board) compiled tables, by age and sex, of all medical services for mild traumatic brain injuries (concussions and minor head injuries) between 2003 and 2016. Quebec's population rates were calculated and yearly graphs were plotted by age and sex.

RESULTS

In Quebec, there were statistically significant increases in rates of mild traumatic brain injury (concussion and minor head injury) in older children: a 2.0-fold increase for those aged 13-17 years, and 1.4-fold increase for those aged 9-12 years. When only considering concussions, girls (13-17 years) had more concussions than boys in 2015 and 2016. The increase in the rates of concussion was significantly higher in Ontario than in Quebec: 4.4- vs. 2.2-fold increase.

CONCLUSIONS

The recent increase in rates of mild traumatic brain injuries reported in the scientific literature has also been observed in Quebec. The fact that the rate of visits for mild traumatic brain injury, per person, remained the same from 2003 to 2016 suggests that the increase was not the result of parents seeking more medical services, but that more of them consulted when their child injured his/her head.

Exploring concussion awareness in hockey with a First Nations community in Canada

OBJECTIVE

The purpose of this pilot study was twofold: (1) to begin to understand concussion in youth hockey in a First Nations community in Canada and (2) to determine the impact of a novel concussion education workshop.

DESIGN

A one-group quasiexperimental time series study was undertaken.

SAMPLE

A total of 41 participants consented, with 71% (n = 29) completing data collection at all three study time points.

MEASUREMENT AND INTERVENTIONS

Two nurses one from the First Nations community and one from the tertiary care center collaborated to develop and deliver the intervention on concussion specifically general, hockey and symptom knowledge. The primary outcome was Total Knowledge Score (TKS), whereby correct responses to a self-reported questionnaire were summed and then converted to a percentage.

RESULTS

The TKS were similar across study time points; preworkshop 71.7%, postworkshop 71.8%, and 6-month follow-up 72%.

CONCLUSIONS

Nurses worked collaboratively with cultural experts from a First Nations community to integrate Indigenous ways of knowing into concussion awareness and safety for First Nations youth playing hockey.

Knowledge, Attitudes and Concussion Information Sources Among First Nations in Ontario

OBJECTIVE

Hockey is a popular sport played by many First Nation youth. Concussion frequently goes unrecognized and unreported in youth hockey. Unintentional injuries among Indigenous youth occur at rates three to four times the national Canadian average. The study sought to examine knowledge, attitudes and sources of concussion information among First Nations people attending a provincial hockey tournament.

METHODS

A cross-sectional survey was undertaken. The survey by Mzazik et al. were modified to use in this study. Participants included youth (6-18 years) hockey players (n=75), parents (n=248) and coaches (n=68). The main outcome measure was total knowledge index (TKI) which consisted of the sum of correct responses to 15 multiple choice questions. Additional data gathered included demographics, concussion history, attitudes toward concussion and sources of information. Descriptive statistics included proportion comparisons. Variables were tested using χ 2 and analysis of variance.

RESULTS

Overall TKI scores (out of a total of 15) were low; players (5.9±2.8), parents (7.5±2.6) and coaches (7.9±2.6). Participants with higher knowledge scores reported more appreciation of the seriousness of concussion. Sources of information about concussion differed by study group, suggesting the need for multiple knowledge translation strategies to reach youth, parents and coaches.

CONCLUSIONS

Future initiatives are urgently needed to improve education and prevention of concussion in First Nations youth hockey. Collaborating and engaging with communities can help to ensure an Indigenous lens for culturally safe interventions.

Is Concussion a Risk Factor for Epilepsy?

Background: Epidemiologic studies have suggested that concussion, or mild traumatic brain injury (mTBI), is associated with a twofold or greater increase in relative risk for the development of post-traumatic epilepsy. To assess the clinical validity of these findings, we analyzed the incidence of epilepsy in a large cohort of post-concussion patients in whom concussion was strictly defined according to international guidelines. Methods: A retrospective cohort study of 330 consecutive post-concussion patients followed by a single concussion specialist. Exclusion criteria: abnormal brain CT/MRI, Glasgow Coma Scale<13 more than 1-hour post-injury, hospitalization >48 hours. Independent variable: concussion. Outcome measure: epilepsy incidence (dependent variable). Results: The mean number of concussions/patient was 3.3 (±2.5), mean age at first clinic visit 28 years (±14.7), and mean follow-up after first concussion 7.6 years (±10.8). Eight patients were identified whose medical records included mention of seizures or convulsions or epilepsy. Upon review by an epileptologist none met criteria for a definite diagnosis of epilepsy: four had episodic symptoms incompatible with epileptic seizures (e.g., multifocal paraesthesiae, multimodality hallucinations, classic migraine) and normal EEG/MRI investigations; four had syncopal (n=2) or concussive (n=2) convulsions. Compared with annual incidence (0.5/1000 individuals) in the general population, there was no difference in this post-concussion cohort (p=0.49). Conclusion: In this large cohort of post-concussion patients we found no increased incidence of epilepsy. For at least the first 5-10 years post-injury, concussion/mTBI should not be considered a significant risk factor for epilepsy. In patients with epilepsy and a past history of concussion, the epilepsy should not be presumed to be post-traumatic.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

CNS Injury: Posttranslational Modification of the Tau Protein as a Biomarker

The ideal biomarker for central nervous system (CNS) trauma in patients would be a molecular marker specific for injured nervous tissue that would provide a consistent and reliable assessment of the presence and severity of injury and the prognosis for recovery. One candidate biomarker is the protein tau, a microtubule-associated protein abundant in the axonal compartment of CNS neurons. Following axonal injury, tau becomes modified primarily by hyperphosphorylation of its various amino acid residues and cleavage into smaller fragments. These posttrauma products can leak into the cerebrospinal fluid or bloodstream and become candidate biomarkers of CNS injury. This review examines the primary molecular changes that tau undergoes following traumatic brain injury and spinal cord injury, and reviews the current literature in traumatic CNS biomarker research with a focus on the potential for hyperphosphorylated and cleaved tau as sensitive biomarkers of injury.