Increasing Incidence of Concussion: True Epidemic or Better Recognition?

Return to work in persons with persistent postconcussion symptoms: a survey study examining the perspectives of employees and managers

OBJECTIVE

To examine challenges in return to work (RTW) for persons with persistent postconcussion symptoms (PPCS) experienced by the affected employees and their managers.

METHODS

A survey of employees (S-E) and two surveys of managers (S-M1, S-M2) executed 4 months apart to capture the time perspective. Inclusion: Adults aged 18-66 with PPCS > 4 weeks, employed at the time of mTBI who returned to work within the previous year. Managers involved in their RTW process.

OUTCOME MEASURES

Work status, working hours, work functioning (Work Role Functioning Questionnaire, WRFQ), work productivity.

RESULTS

Ninety-two employees and 66 managers were recruited. Three-fourths of the employees had returned to work but only one-third worked under similar conditions. Weekly working hours decreased from 36,3 hours (SD = 10,5) before mTBI to 17,6 hours (SD = 9,7). Employees had difficulties with tasks 43% of time (WRFQ). They needed more breaks, struggled with multitasking and work speed. About 65.9% experienced affected work productivity. Managers reported lack of knowledge and difficulties assessing the number of working hours and suitable tasks.

CONCLUSIONS

Most employees returned to work but only a minority worked under similar conditions as before mTBI. Employees and managers struggled to estimate workload. The affected employees and their workplaces need a long-term RTW support.

Posttraumatic stress symptoms in recovery from concussion

BACKGROUND

Previous literature suggests that lingering concussion symptoms may be influenced by psychological factors. The relationship of posttraumatic stress symptoms (PTSS) during recovery with pre-existing/injury related factors and concussion symptomology is not fully understood. Identification of factors contributing to symptoms of posttraumatic stress may provide guidance to improve treatment following concussion.

METHOD

This study included 287 participants (Male 40.42%, n = 116; Female 59.58%, n = 171) aged 13-75 years diagnosed with a recent concussion at one of the North Texas Concussion Registry (ConTex) specialty concussion clinic sites. Preinjury emotional history, injury related factors, and emotional state at time of initial evaluation were analyzed as predictors of post-traumatic stress symptoms (PCL-5) during recovery.

RESULTS

Sixty-one percent of participants endorsed at least one PTSS. Correlations were found between initial Sport Concussion Assessment Tool 5Ⓡ (SCAT5) total emotional symptom severity and screening measures for anxiety (GAD-7; r = .453, p < .001) and depression (PHQ-8; r = .550, p < .001) symptom scores. Of the measures from the initial visit included in the multiple regression model predicting severity of PTSS at follow-up (R2 = 0.554, β < .001), three measures predicted PTSS severity: initial SCAT5 total emotional symptom severity (β = 0.565, p < .001), PHQ-8 score (β =.166, p = .009), and GAD-7 score (β = 0.119, p = .044).

CONCLUSIONS

Symptoms of anxiety and depression along with specific SCAT5 emotional symptoms present at the time of initial evaluation may serve to predict overall level of PTSS and increased risk for PTSS during recovery. PTSS may be another dimension of response to injury and concussion recovery, with a large percentage of individuals endorsing at least one PTSS. Clinicians can utilize brief assessments such as the SCAT5 at the time of initial clinical evaluation to identify those at risk for PTSS following concussion.

Feasibility of superimposed supine cycling and lower body negative pressure as an effective means of prolonging exercise tolerance in individuals experiencing persisting post-concussive symptoms: Preliminary results

To examine the feasibility, utility and safety of superimposed lower body negative pressure (LBNP) and tilt during supine cycling in individuals suffering from persisting post-concussive symptoms (PPCS). Eleven individuals aged 17-31 (6 females/5 males) participated in two randomized separate visits, 1 week apart. A ramp-incremental test was performed during both visits until volitional failure. Visits included no pressure (control) or LBNP at -40 Torr (experimental) with head-up tilt at 15 degrees (females) or 30 degrees (males). Transcranial Doppler ultrasound was utilized to quantify middle cerebral artery velocity (MCAv), while symptom reports were filled out before and 0, 10, and 60 min post-exertion. Ratings of exertion and overall condition followed similar trends for participants across both tests. The relative increase in MCAv was blunted during the experimental condition (8%) compared to control (24%), while a greater heart rate (17 beats/min) was achieved during the LBNP condition (P = 0.047). Symptom severity at the 0 and 10 min post-exertion time points displayed negligible-to-small effect sizes between conditions (Wilcoxon's r < 0.11). Symptom reporting was lower at the 60 min post-exertion time point with these displaying a moderate effect size (Wilcoxon's r = 0.31). The combination of LBNP and tilt during supine cycling did not change the participants' subjective interpretation of the exertional test but attenuated the hyperpnia-induced vasodilatory MCAv response, while also enabling participants to achieve a higher heart rate during exercise and reduced symptoms 1 h later. As this protocol is safe and feasible, further research is warranted in this area for developing PPCS treatment options. HIGHLIGHTS: What is the central question of this study? What are the feasibility, safety and utility of combining head-up tilt with lower body negative pressure during supine cycling for blunting the increase in cerebral blood velocity seen during moderate-intensity exercise in individuals experiencing persisting post-concussion symptoms? What is the main finding and its importance? Although no differences were found in symptoms between conditions within the first 10 min following exertion, symptom severity scores showed a clinically meaningful reduction 60 min following the experimental condition compared to the non-experimental control condition.

Social Norms and Concussion Disclosure Behavior: Clarification of Terms and Measurement Recommendations

Nondisclosed sport-related concussion symptoms pose a significant risk to athletes' health and well-being. Many researchers have focused on understanding the factors affecting athletes' concussion disclosure behaviors. One of the most robust predictors of the likelihood that an athlete will disclose concussion symptoms to their coaches, athletic trainers, parents, or peers is what researchers term social norms. The extant literature regarding social norms influencing concussion disclosure behaviors is inconsistent on how the construct should be defined, conceptualized, or measured, often failing to distinguish between descriptive and injunctive social norms and their sources (direct and indirect). In this technical note, we provide an overview of these critical distinctions, their importance in assessments, and examples from the literature in which scholars have correctly operationalized these constructs in athletic populations. We conclude with a brief set of suggestions for researchers seeking to measure social norms in future research.

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.

A Cross-Sectional Investigation of Trait Mindfulness, Concussion Symptom Severity, and Quality of Life in Adults with Persisting Symptoms Postconcussion

Individual differences in mindfulness may impact quality of life after concussion. In a cross-sectional analysis, the moderating effect of mindfulness was tested on the association between symptom severity and quality of life in adults with persisting postconcussion symptoms (N = 85). Mindfulness and symptom severity were independently associated with quality of life; however, mindfulness did not moderate this association. "Nonreactivity" was independently associated with quality of life; however, it was not a significant moderator. Taking a nonreactive stance, or allowing experiences to come and go without effort to change them, may be relevant to quality-of-life outcomes after concussion.

The Concussion, Exercise, and Brain Networks (ConExNet) study: a cohort study aimed at understanding the effects of sub-maximal aerobic exercise on resting state functional brain activity in pediatric concussion

BACKGROUND

Recent scientific evidence has challenged the traditional "rest-is-best" approach for concussion management. It is now thought that "exercise-is-medicine" for concussion, owing to dozens of studies which demonstrate that sub-maximal, graded aerobic exercise can reduce symptom burden and time to symptom resolution. However, the primary neuropathology of concussion is altered functional brain activity. To date, no studies have examined the effects of sub-maximal aerobic exercise on resting state functional brain activity in pediatric concussion. In addition, although exercise is now more widely prescribed following concussion, its cardiopulmonary response is not yet well understood in this population. Our study has two main goals. The first is to understand whether there are exercise-induced resting state functional brain activity differences in children with concussion vs. healthy controls. The second is to profile the physiological response to exercise and understand whether it differs between groups.

METHODS

We will perform a single-center, controlled, prospective cohort study of pediatric concussion at a large, urban children's hospital and academic center. Children with sport-related concussion (aged 12-17 years) will be recruited within 4-weeks of injury by our clinical study team members. Key inclusion criteria include: medical clearance to exercise, no prior concussion or neurological history, and no implants that would preclude MRI. Age- and sex-matched healthy controls will be required to meet the same inclusion criteria and will be recruited through the community. The study will be performed over two visits separated by 24-48 h. Visit 1 involves exercise testing (following the current clinical standard for concussion) and breath-by-breath gas collection using a metabolic cart. Visit 2 involves two functional MRI (fMRI) scans interspersed by 10-minutes of treadmill walking at an intensity calibrated to Visit 1 findings. To address sub-objectives, all participants will be asked to self-report symptoms daily and wear a waist-worn tri-axial accelerometer for 28-days after Visit 2.

DISCUSSION

Our study will advance the growing exercise-concussion field by helping us understand whether exercise impacts outcomes beyond symptoms in pediatric concussion. We will also be able to profile the cardiopulmonary response to exercise, which may allow for further understanding (and eventual optimization) of exercise in concussion management.

TRIAL REGISTRATION

Not applicable.

Efficacy of restitutive interventions for oculomotor deficits in adults with mild traumatic brain injury: a systematic review and meta-analysis

BACKGROUND

Mild traumatic brain injury (mTBI) can cause persistent symptoms suggestive of oculomotor deficits. This research synthesized evidence on restitutive interventions for reducing oculomotor deficits in adults with mTBI to understand if these interventions have clinical utility for improving recovery.

METHODS

Medline, EMBASE, CINHAL, PsychInfo, and Scopus, databases were searched for experimental studies published in English. We rated risk of bias (RoB) using recommended tools, and the certainty of the evidence according to GRADE guidelines. We conducted meta-analyses for similar outcomes reported in at least two studies.

RESULTS

Out of 5,328 citations, 12 studies (seven case series and five crossover design), with a combined sample size of 354 participants; (43% males) met the inclusion criteria and were analyzed. The analysis revealed a trend toward improvement of oculomotor deficits and visual tasks in response to restitutive intervention. None of the studies addressed sex or gender effects. All studies had high RoB, suggesting low certainty in the reported results.

DISCUSSION

Restitutive interventions may be beneficial for adults with oculomotor deficits after mTBI, however overall certainty of the evidence remains low. Future efforts must include enhancing attention to study methodology and reporting, sex and gender analyses, and reaching a consensus on outcome measures.

PROSPERO REGISTRATION NUMBER

CRD42022352276.

Elevated Autoantibodies to the GluA1 Subunit of the AMPA Receptor in Blood Indicate Risk of Cognitive Impairment in Contact Sports Athletes, Irrespective of Concussion

To address the need for objective tests of concussion in athletes, we conducted a prospective clinical study in National Collegiate Athletic Association athletes of the relationship between neurocognitive performance and blood levels of the GluA1 subunit of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor peptides and autoantibodies to GluA1. Specifically, we compared 44 contact sport athletes to 16 noncontact sport athletes, with Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), as well as blood sample collection, before the start of the season and at the end of the season. Contact sport athletes exhibited significantly elevated serum GluA1 autoantibodies at the end of season, compared with preseason levels, irrespective of whether they sustained a concussion. Noncontact sport athletes showed no change in serum GluA1 autoantibodies, and neither group showed differences in GluA1 peptides. Amongst contact-sport athletes, the 'high GluA1 autoantibody group' (≥4 ng/mL) displayed impaired reaction time, a measure of cognitive impairment, while the 'low GluA1 autoantibody group' (<4 ng/mL) displayed normal reaction time. Our results reveal that contact sport athletes are at risk for developing cognitive impairment even without sustaining a diagnosed concussion and that serum GluA1 autoantibodies provide a blood-based biomarker of this risk. This could guide future studies on the differing susceptibility to cognitive impairment in contact sport athletes and facilitate efficient allocation of resources to contact sport athletes identified as having increased risk of developing cognitive impairment.

Assessment of post-concussion emotional symptom load using PCSS and PROMIS instruments in pediatric patients

OBJECTIVES

The purpose of this study is to evaluate the utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety and depressive symptom domains in conjunction with the Post-Concussion Symptom Scale (PCSS)for identifying pediatric patients with emotional symptoms following a concussion, and to identify predictors of higher emotional symptom loads.

METHODS

We recruited English-speaking patients aged 8-17 years presenting to a tertiary-care concussion clinic from 2014 to 2018 (n = 458). Demographics and clinical data including PCSS, injury date, previous history of anxiety/depression, and Vestibular/Ocular-Motor Screen (VOMS) were collected from patients' electronic medical records. Participants completed surveys in the PROMISTM Pediatric Item Bank v1.1-Anxiety and Depressive Symptoms domains at their initial clinic visit. Multivariable linear regression identified predictors of higher emotional symptom loads.

RESULTS

Overall, 425 (92.8%) reported ≥1 emotional symptom on either PROMIS or PCSS. Predictors of higher emotional symptom loads were abnormal VOMS, female sex, history of anxiety or depression, and longer time since injury.

CONCLUSION

Our results suggest that adding PROMIS anxiety and depressive symptom surveys to pediatric concussion evaluations may identify more children with emotional symptoms, allowing clinicians to better direct post-concussion treatment and incorporate psychological support for patients if necessary. Future studies should examine whether earlier identification of emotional symptoms with these tools facilitates recovery and improves short- and/or long-term psychological outcomes in pediatric concussion.

Cause of Concussion With Persisting Symptoms Is Associated With Long-Term Recovery and Symptom Type, Duration, and Number in a Longitudinal Cohort of 600 Patients

It is important for patients and clinicians to know the potential for recovery from concussion as soon as possible after injury, especially in patients who do not recover completely in the first month and have concussion with persisting concussion symptoms (C+PCS). We assessed the association between the causes of concussion and recovery from C+PCS in a consecutive retrospective and prospective cohort of 600 patients referred to the Canadian Concussion Center (CCC) at Toronto Western Hospital. Data were obtained from clinical records and follow-up questionnaires and not from a standardized database. A novel method was used to assess long-term recovery, and multi-variable Cox proportional hazards models were used to assess relationships between cause of concussion and time to recovery. We examined the subsequent recovery of patients who had not recovered after at least one month from the time of concussion. Patients were grouped into the following four causes: sports and recreation (S&R, n = 312, 52%); motor vehicle collisions (MVC, n = 103, 17%); falls (n = 100, 17%); and being struck by an object including violence (SBOV, n = 85, 14%). The MVC group had the highest percentage of females (75.7%), the oldest participants (median: 40.0 [interquartile range (IQR):30.5-49.0] years), the most symptoms (median:11.0 [IQR:8.5-15.0]), and the longest symptom duration (median: 28.0 [IQR:12.0-56.00] months). In contrast, the S&R group had the highest percentage of males (58.1%), the youngest participants (median:20.0 [IQR:17.0-30.0] years), the best recovery outcome, and shortest symptom duration (median:22.0 [IQR:8.0-49.5] months). Significant differences among the four causes included age (p < 0.001), sex (p < 0.001), number of previous concussions (p < 0.001), history of psychiatric disorders (p = 0.002), and migraine (p = 0.001). Recovery from concussion was categorized into three groups: (1) Complete Recovery occurred in only 60 (10%) patients with median time 8.0 (IQR:3.5-18.0) months and included 42 S&R, 7 MVC, 8 falls, and 3 SBOV; (2) Incomplete Recovery occurred in 408 (68.0%) patients with persisting median symptom time of 5.0 (IQR:2.0-12.0) months; and (3) Unknown Recovery occurred in 132 (22.0%) patients and was because of lack of follow-up. In summary, the cause of C+PCS was associated with the type, number, and duration of symptoms and time required for recovery, although all causes of C+PCS produced prolonged symptoms in a large percentage of patients, which emphasizes the importance of concussions as a public health concern necessitating improved prevention and treatment strategies.

Functional Neurological Disorder Presenting After Concussion: A Retrospective Case Series

OBJECTIVE

Although a majority of individuals recover from a concussion within weeks of the index injury, a substantial minority of patients report persistent postconcussion symptoms. Some of these symptoms may reflect a diagnosis of functional neurological disorder (FND). The authors evaluated the relationship between persistent postconcussion symptoms and FND symptoms.

METHODS

In this retrospective chart review, the authors characterized demographic and clinical information from 50 patients with a confirmed diagnosis of FND whose functional neurological symptoms started after a concussion.

RESULTS

Patients who developed FND after a concussion had high rates of baseline risk factors for both persistent postconcussion symptoms and FND. After the concussive event, functional neurological symptoms presented abruptly or developed insidiously over time. Functional neurological symptoms ranged widely and included gait symptoms, seizures, speech and language symptoms, weakness, sensory symptoms, tremors, and vision and oculomotor symptoms.

CONCLUSIONS

Functional neurological symptoms can arise after a concussion. FND should be considered in the differential diagnosis of individuals presenting with neurological symptoms beginning after a concussion. By failing to recognize functional symptoms, clinicians may inadvertently reinforce negative health-related beliefs regarding a patient's injured brain.

The Postconcussion Syndrome and Posttraumatic Headaches in Civilians, Soldiers, and Athletes

Posttraumatic headaches are one of the most common and controversial secondary headache types. After a mild traumatic brain, an estimated 11% to 82% of people develop a postconcussion syndrome, which has been controversial for more than 160 years. Headache is estimated as present in 30% to 90% of patients after a mild head injury. Most headaches are tension-type-like or migraine-like. Headaches in civilians, soldiers, athletes, and postcraniotomy are reviewed. The treatments are the same as for the primary headaches. Persistent posttraumatic headaches can continue for many years.

Early Blood-Brain Barrier Impairment as a Pathological Hallmark in a Novel Model of Closed-Head Concussive Brain Injury (CBI) in Mice

Concussion, caused by a rotational acceleration/deceleration injury mild enough to avoid structural brain damage, is insufficiently captured in recent preclinical models, hampering the relation of pathophysiological findings on the cellular level to functional and behavioral deficits. We here describe a novel model of unrestrained, single vs. repetitive concussive brain injury (CBI) in male C56Bl/6j mice. Longitudinal behavioral assessments were conducted for up to seven days afterward, alongside the evaluation of structural cerebral integrity by in vivo magnetic resonance imaging (MRI, 9.4 T), and validated ex vivo by histology. Blood-brain barrier (BBB) integrity was analyzed by means of fluorescent dextran- as well as immunoglobulin G (IgG) extravasation, and neuroinflammatory processes were characterized both in vivo by positron emission tomography (PET) using [18F]DPA-714 and ex vivo using immunohistochemistry. While a single CBI resulted in a defined, subacute neuropsychiatric phenotype, longitudinal cognitive testing revealed a marked decrease in spatial cognition, most pronounced in mice subjected to CBI at high frequency (every 48 h). Functional deficits were correlated to a parallel disruption of the BBB, (R2 = 0.29, p < 0.01), even detectable by a significant increase in hippocampal uptake of [18F]DPA-714, which was not due to activation of microglia, as confirmed immunohistochemically. Featuring a mild but widespread disruption of the BBB without evidence of macroscopic damage, this model induces a characteristic neuro-psychiatric phenotype that correlates to the degree of BBB disruption. Based on these findings, the BBB may function as both a biomarker of CBI severity and as a potential treatment target to improve recovery from concussion.

Reduced influence of perceptual context in mild traumatic brain injury is not an illusion

Perceptual grouping is impaired following mild traumatic brain injury (mTBI). This may affect visual size perception, a process influenced by perceptual grouping abilities. We conducted two experiments to evaluate visual size perception in people with self-reported history of mTBI, using two different size-contrast illusions: the Ebbinghaus Illusion (Experiment 1) and the Müller-Lyer illusion (Experiment 2). In Experiment 1, individuals with mTBI and healthy controls were asked to compare the size of two target circles that were either the same size or different sizes. The target circles appeared by themselves (no-context condition), or were surrounded by smaller or larger circles (context condition). Similar levels of accuracy were evident between the groups in the no-context condition. However, size judgements by mTBI participants were more accurate in the context condition, suggesting that they processed the target circles separately from the surrounding circles. In Experiment 2, individuals with mTBI and healthy controls judged the length of parallel lines that appeared with arrowheads (context condition) or without arrowheads (no context condition). Consistent with Experiment 1, size judgements by mTBI participants were more accurate than size judgements by control participants in the context condition. These findings suggest that mTBI influences size perception by impairing perceptual grouping of visual stimuli in near proximity.

Conservative Management of Acute Sports-Related Concussions: A Narrative Review

This review explores the application of the conservative management model for pain to sports-related concussions (SRCs), framing concussions as a distinct form of pain syndrome with a pathophysiological foundation in central sensitization. Drawing parallels with proven pain management models, we underscore the significance of a proactive approach to concussion management. Recognizing concussions as a pain syndrome allows for the tailoring of interventions in alignment with conservative principles. This review first covers the epidemiology and controversies surrounding prolonged concussion recovery and persistent post-concussion symptoms (PPCS). Next, the pathophysiology of concussions is presented within the central sensitization framework, emphasizing the need for early intervention to mitigate the neuroplastic changes that lead to heightened pain sensitivity. Five components of the central sensitization process specific to concussion injuries are highlighted as targets for conservative interventions in the acute period: peripheral sensitization, cerebral metabolic dysfunction, neuroinflammation, glymphatic system dysfunction, and pain catastrophizing. These proactive interventions are emphasized as pivotal in accelerating concussion recovery and reducing the risk of prolonged symptoms and PPCS, in line with the philosophy of conservative management.

CONNECTing Concussion Care with Research Across Ontario

Common data elements (CDEs) for concussion, as established by international bodies, are not being widely used in Ontario, resulting in significant variability in the data being assessed and collected across clinics. CDEs support standardization of care as well as large-scale data sharing for high impact research. A collaborative network - Concussion Ontario Network: Neuroinformatics to Enhance Clinical care and Translation (CONNECT) - comprised of health care professionals, researchers, members from advocacy groups, and patients was formed to establish and implement CDEs for concussion care and research. While the seeds have been planted and initial effectiveness demonstrated, future challenges exist.

Labour market attachment dynamics in patients with concussion: a Danish nationwide register-based cohort study

BACKGROUND

Concussion may lead to persisting post-concussive symptoms affecting work ability and employment. This study examined the transitions between labour market states an individual can experience after the acute phase of concussion. The aim was to describe the incidence of favourable and adverse transitions between different labour market states (e.g., employment, sick leave) in relation to socioeconomic and health characteristics in individuals with concussion relative to matched controls.

METHODS

This Danish nationwide register-based cohort study extracted 18-60-year-old individuals between 2003-2007 with concussion from the Danish National Patient Register (ICD-10 S06.0). Controls were matched on age, sex, and municipality. Patients and controls were followed for 5 years starting three months after injury. Exclusion criteria were neurological injuries and unavailability to the labour market in the inclusion period (2003-2007) and 5-years before injury (1998-2002). Labour market states were defined from transfer income data in the Danish Register for Evaluation of Marginalization. Incidence rates of transitions between these labour market states were analysed in multistate models. Transitions were bundled in favourable and adverse transitions between labour market states and the difference in incidence rates between individuals with concussion relative to matched controls were assessed with hazard ratios from Cox regression models.

RESULTS

Persons with concussion (n = 15.580) had a lower incidence of favourable transitions (HR 0.88, CI 0.86-0.90) and a higher incidence of adverse transitions (HR 1.30, CI 1.27-1.35), relative to matched controls (n = 16.377). The effect of concussion differed depending on health and socioeconomic characteristics. Notably, individuals between 30-39 years (HR 0.83, CI 0.79-0.87), individuals with high-income (200.000-300.000 DKK) (HR 0.83, CI 0.80-0.87), and wage earners with management experience (HR 0.60, CI 0.44-0.81) had a markedly lower incidence of favourable transitions compared to controls. Additionally, individuals with high income also had a higher incidence of adverse transitions (HR 1.46, CI 1.34-1.58) compared to controls.

CONCLUSIONS

Concussion was associated with enhanced risk of adverse transitions between labour market states and lower occurrence of favourable transitions, indicating work disability, potentially due to persistent post-concussive symptoms. Some age groups, individuals with high income, and employees with management experience may be more affected.

Injury Incidence, Outcomes, and Return to Competition Times after Sports-Related Concussions during One Professional Ice Hockey Season: A Prospective Cohort Study

OBJECTIVE

The objective of this study was to analyze the incidence and characteristics of sports-related concussions (SRCs) for a professional ice hockey team during one regular season in the International Central European Hockey League.

BACKGROUND

Repeated concussions are a common cause of long periods of absence in team contact sports, with a wide range of potential short- and long-term consequences for the affected athlete. Questions mainly regarding early diagnosis and ideal follow-up treatment remain unanswered, especially regarding the timing of return to sports (RTS).

METHOD

A prospective data analysis for a professional ice hockey team during a regular season was conducted. Firstly, concussions per 1000 athlete exposure (AE) and average time loss due to SRC were calculated. Secondly, the data from ImPACT Applications were analyzed for those players who were diagnosed with an SRC.

RESULTS

Five SRCs were evaluated during the regular season, which resulted in 1.35 concussions/1000 AEs, a maximum of 17 missed games, and a median of three games per SRC. The average symptom count was 9.6, with the most common symptoms being headache, sensitivity to light, and dizziness.

CONCLUSIONS

SRCs sustained in professional ice hockey are a common in-competition injury, while practices play a subsidiary role. The duration of RTS is highly individual and can be associated with symptoms lasting days to months.

Specialist healthcare services for concussion/mild traumatic brain injury in England: a consensus statement using modified Delphi methodology

OBJECTIVE

To establish a consensus on the structure and process of healthcare services for patients with concussion in England to facilitate better healthcare quality and patient outcome.

DESIGN

This consensus study followed the modified Delphi methodology with five phases: participant identification, item development, two rounds of voting and a meeting to finalise the consensus statements. The predefined threshold for agreement was set at ≥70%.

SETTING

Specialist outpatient services.

PARTICIPANTS

Members of the UK Head Injury Network were invited to participate. The network consists of clinical specialists in head injury practising in emergency medicine, neurology, neuropsychology, neurosurgery, paediatric medicine, rehabilitation medicine and sports and exercise medicine in England.

PRIMARY OUTCOME MEASURE

A consensus statement on the structure and process of specialist outpatient care for patients with concussion in England.

RESULTS

55 items were voted on in the first round. 29 items were removed following the first voting round and 3 items were removed following the second voting round. Items were modified where appropriate. A final 18 statements reached consensus covering 3 main topics in specialist healthcare services for concussion; care pathway to structured follow-up, prognosis and measures of recovery, and provision of outpatient clinics.

CONCLUSIONS

This work presents statements on how the healthcare services for patients with concussion in England could be redesigned to meet their health needs. Future work will seek to implement these into the clinical pathway.

Racial differences in concussion diagnosis and mechanism of injury among adults presenting to emergency departments across the United States

OBJECTIVES

The purpose of this study was to examine the association between race and concussion diagnosis as well as the association between race and mechanism of injury (MOI) for concussion diagnoses in adult patients (>19 years old) visiting the emergency department (ED).

METHODS

A retrospective analysis of patient visits to the ED for concussion between 2010 and 2018, using the National Hospital Ambulatory Medical Care Survey, was conducted. Outcome measures included concussion diagnosis and MOI. Multivariable and multinomial logistic regression analyses were conducted to assess associations between race and outcome variables. The results were weighted to reflect population estimates with a significance set at p < 0.05.

RESULTS

Overall, 714 patient visits for concussions were identified, representing an estimated 4.3 million visits nationwide. Black adults had lower odds of receiving a concussion diagnosis [p < 0.05, Odds Ratio (OR), 0.54; 95% Confidence Interval (CI), 0.38-0.76] compared to White adults in the ED. There were no significant differences in MOI for a concussion diagnosis by race.

CONCLUSION

Racial differences were found in the ED for concussion diagnosis. Disparities in concussion diagnosis for Black or other minoritized racial groups could have significant repercussions that may prolong recovery or lead to long-term morbidity.

Hippocampal interneuronal dysfunction and hyperexcitability in a porcine model of concussion

Cognitive impairment is a common symptom following mild traumatic brain injury (mTBI or concussion) and can persist for years in some individuals. Hippocampal slice preparations following closed-head, rotational acceleration injury in swine have previously demonstrated reduced axonal function and hippocampal circuitry disruption. However, electrophysiological changes in hippocampal neurons and their subtypes in a large animal mTBI model have not been examined. Using in vivo electrophysiology techniques, we examined laminar oscillatory field potentials and single unit activity in the hippocampal network 7 days post-injury in anesthetized minipigs. Concussion altered the electrophysiological properties of pyramidal cells and interneurons differently in area CA1. While the firing rate, spike width and amplitude of CA1 interneurons were significantly decreased post-mTBI, these parameters were unchanged in CA1 pyramidal neurons. In addition, CA1 pyramidal neurons in TBI animals were less entrained to hippocampal gamma (40-80 Hz) oscillations. Stimulation of the Schaffer collaterals also revealed hyperexcitability across the CA1 lamina post-mTBI. Computational simulations suggest that reported changes in interneuronal physiology may be due to alterations in voltage-gated sodium channels. These data demonstrate that a single concussion can lead to significant neuronal and circuit level changes in the hippocampus, which may contribute to cognitive dysfunction following mTBI.

Characterizing the profiles of patients with acute concussion versus prolonged post-concussion symptoms in Ontario

Identifying vulnerability factors for developing persisting concussion symptoms is imperative for determining which patients may require specialized treatment. Using cross-sectional questionnaire data from an Ontario-wide observational concussion study, we compared patients with acute concussion (≤ 14 days) and prolonged post-concussion symptoms (PPCS) (≥ 90 days) on four factors of interest: sex, history of mental health disorders, history of headaches/migraines, and past concussions. Differences in profile between the two groups were also explored. 110 patients with acute concussion and 96 patients with PPCS were included in our study. The groups did not differ on the four factors of interest. Interestingly, both groups had greater proportions of females (acute concussion: 61.1% F; PPCS: 66.3% F). Patient profiles, however, differed wherein patients with PPCS were significantly older, more symptomatic, more likely to have been injured in a transportation-related incident, and more likely to live outside a Metropolitan city. These novel risk factors for persisting concussion symptoms require replication and highlight the need to re-evaluate previously identified risk factors as more and more concussions occur in non-athletes and different risk factors may be at play.

Rehabilitation interventions for oculomotor deficits in adults with mild traumatic brain injury: a systematic review protocol

INTRODUCTION

Mild traumatic brain injury (mTBI) is the most common form of TBI with many individuals suffering from symptoms suggestive of deficits in oculomotor function. Although the symptoms are often experienced transiently, almost 50% of individuals will experience persistent symptoms. Oculomotor deficits can last months after injury and decrease function and the ability to participate in work, school and sport. To date, rehabilitation interventions targeting oculomotor deficits in mTBI have been reported on in several studies with varying study designs; however, the effectiveness of these interventions on measures of oculomotor function has not been established. The purpose of this paper is to present a protocol for a systematic review that aims to examine the effectiveness of rehabilitation interventions for improving function in adults with oculomotor deficits after mTBI.

METHODS AND ANALYSIS

Systematic searches in Medline Ovid, EMBASE, PsycINFO, CINAHL and Scopus will be conducted to identify experimental studies published in English from each databases inception date to present, involving adult patients with mTBI and oculomotor deficits. Citations will be saved and managed in EndNote V.20. Two independent reviewers will identify eligible studies and perform data abstraction. Any discrepancies will be solved by discussion, and a third reviewer will be consulted if necessary. A meta-analysis will be conducted for outcomes reported in two or more studies. The Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol guidelines will be followed for reporting.

ETHICS AND DISSEMINATION

This study does not involve primary data collection; therefore, formal ethical approval by an institutional review board is not required. Final results will be disseminated through open-access peer-reviewed publications. Abstracts will be presented at suitable national and international conferences or workshops. Furthermore, important information will be shared with clinical authorities, clinicians and at affiliated research institution-based websites and relevant servers.

PROSPERO REGISTRATION NUMBER

CRD42022352276.

Risk of impaired school performance in children hospitalized with concussion: a population-based matched cohort study

Aim

To examine the impact of concussion on objective measures of school performance.

Materials & methods

Population-based matched cohort study using linked health and education records of young people aged ≤18 years hospitalized with concussion in New South Wales, Australia, during 2005-2018, and matched comparisons not hospitalized with any injury.

Results

Young people with concussion had higher risk of not achieving the national minimum standards for literacy and numeracy assessments, ranging from 30% for numeracy to 43% for spelling, and not completing high school, ranging from 29% for year 10 to 77% for year 12, compared with matched peers.

Conclusion

Young people hospitalized with concussion have impaired school performance compared with uninjured matched peers.

Examining the interdisciplinary approach for treatment of persistent post-concussion symptoms in adults: a systematic review

BACKGROUND

The objective of this review is to examine the evidence for the interdisciplinary approach in treatment of persistent post-concussion symptoms in adults.

METHODS

This systematic literature search was undertaken according to the Preferred Reporting Items for Systematic and Meta-Analysis (PRISMA) guidelines. Five electronic databases were searched: CINAHL, Informit, ProQuest, PubMed and Scopus. After screening and quality assessment, the review included six studies published in English and peer-reviewed journals, between 2011 and 2021 to return contemporary evidence.

RESULTS

The results revealed that there was significant variation between measures used and the timing of the pre- and post-treatment assessment. The studies found an interdisciplinary approach to be beneficial, however, the challenges of inherent heterogeneity, lack of clarity for definitions and diagnosis, and mixed results were apparent. The interdisciplinary interventions applied in all identified studies were found to reduce post-concussion symptoms across the symptom subtypes: headache/migraine, vestibular, cognitive, ocular motor and anxiety/mood.

CONCLUSIONS

The results demonstrated evidence for a reduction in persistent post-concussion symptoms following interdisciplinary intervention. This evidence will inform health services, clinicians, sports administrators and researchers with regard to concussion clinic and rehabilitation team design and service delivery.

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.

The Toronto Concussion Study: a prospective investigation of characteristics in a cohort of adults from the general population seeking care following acute concussion, 2016-2020

Purpose

There is limited research regarding the characteristics of those from the general population who seek care following acute concussion.

Methods

To address this gap, a large cohort of 473 adults diagnosed with an acute concussion (female participants = 287; male participants = 186) was followed using objective measures prospectively over 16 weeks beginning at a mean of 5.1 days post-injury.

Results

Falls were the most common mechanism of injury (MOI) (n = 137, 29.0%), followed by sports-related recreation (n = 119, 25.2%). Male participants were more likely to be injured playing recreational sports or in a violence-related incident; female participants were more likely to be injured by falling. Post-traumatic amnesia (PTA) was reported by 80 participants (16.9 %), and loss of consciousness (LOC) was reported by 110 (23.3%). In total, 54 participants (11.4%) reported both PTA and LOC. Male participants had significantly higher rates of PTA and LOC after their injury compared to their female counterparts. Higher initial symptom burden was associated with a longer duration of recovery for both male and female participants. Female participants had more symptoms and higher severity of symptoms at presentation compared to male participants. Female participants were identified to have a longer recovery duration, with a mean survival time of 6.50 weeks compared to 5.45 weeks in male participants (p < 0.0001). A relatively high proportion of female and male participants in this study reported premorbid diagnoses of depression and anxiety compared to general population characteristics.

Conclusion

Although premorbid diagnoses of depression and/or anxiety were associated with higher symptom burden at the initial visit, the duration of symptoms was not directly associated with a pre-injury history of psychological/psychiatric disturbance. This cohort of adults, from the general population, seeking care for their acute concussion attained clinical and functional recovery over a period of 4-12 weeks.

Pilot study protocol of a randomized controlled trial for the potential effects of creatine monohydrate on persistent post-concussive symptoms

Background

Mild traumatic brain injury or concussion is a global public concern, with an estimated annual incidence between 48 million and 96 million worldwide. It is a socioeconomical problem, and almost one-third of individuals with concussion suffer from severe persistent post-concussive symptoms (PPCS), with an increased risk of unemployment or terminating their studies. To date, no single treatment is available with guaranteed success. Creatine monohydrate (CrM) has shown potential as a treatment for post-concussive symptoms, having a positive impact on cognitive function, chronic fatigue, depression, and anxiety. The aim of this study is to examine the effect of CrM on PPCS assessed using the Rivermead Post-Concussion Symptoms Questionnaire (RPQ).

Methods

The study is designed as a double-blinded randomised controlled trial. Study participants are found through neurological outpatient clinics in Denmark or through social media. They will be between 25 and 35 years of age, will have suffered from PPCS for 6-12 months prior to inclusion, and will have no comorbidities. The participants will be randomly allocated to either an intervention group (INT), placebo group (PLA), or control group (CG). Baseline data will be collected immediately after inclusion, and the study period will be 7 weeks. Follow-up data will be collected 1 week after the end of the study period. The primary outcome of the study is changes in RPQ score. Changes in weight and training status will be adjusted for as potential confounders.

Ethics and dissemination

This protocol is approved by the National Committee on Health Research (97508) and by the Danish Data Protection Agency 11.651. The investigators intend to submit their study findings for publication in peer-reviewed journals and disseminate the findings via presentation at academic meetings/conferences.Clinical Trial registration: NCT05562232, registered September 30, 2022.

Occupational Therapy Practice Guidelines for Adults With Traumatic Brain Injury

IMPORTANCE

Occupational therapy practitioners are uniquely qualified to address the occupational needs of people with traumatic brain injury (TBI) and their caregivers to maximize participation, health, and well-being.

OBJECTIVE

These Practice Guidelines are informed by systematic reviews of the effectiveness of interventions that address impairments and skills to improve the occupational performance of people with TBI, as well as interventions for caregivers of people with TBI. The purpose of these guidelines is to summarize the current evidence available to assist clinicians' clinical decision-making in providing interventions for people with TBI and their caregivers.

METHOD

We reviewed six systematic reviews and synthesized the results into clinical recommendations to be used in occupational therapy clinical practice.

RESULTS

Sixty-two articles served as the basis for the clinical recommendations.

CONCLUSIONS AND RECOMMENDATIONS

Strong to moderate evidence supports multimodal sensory stimulation, unimodal auditory stimulation, physical activity, virtual reality, cognitive interventions, vision therapy, goal-focused interventions, individual and group training and education, and caregiver supports. Occupational therapy practitioners should incorporate these interventions into individual and group sessions to maximize recovery and promote occupational participation. Additional interventions are also available, based on emerging evidence and expert opinion, including prevention approaches, complexity of injury, and the use of occupation-based performance assessments. What This Article Adds: These Practice Guidelines provide a summary of evidence in clinical recommendations tables supporting occupational therapy interventions that address impairments resulting from and skills to improve occupational performance after TBI. The guidelines also include case study examples and evidence graphics for practitioners to use to support clinical reasoning when selecting interventions that address the goals of the person with TBI and their caregiver's needs.

Clinical recovery from concussion-return to school and sport: a systematic review and meta-analysis

OBJECTIVE

To define the time frames, measures used and modifying factors influencing recovery, return to school/learn (RTL) and return to sport (RTS) after sport-related concussion (SRC).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

8 databases searched through 22 March 2022.

ELIGIBILITY CRITERIA

Studies with diagnosed/suspected SRC and interventions facilitating RTL/RTS or investigating the time and modifying factors for clinical recovery. Outcomes included days until symptom free, days until RTL and days until RTS. We documented study design, population, methodology and results. Risk of bias was evaluated using a modified Scottish Intercollegiate Guidelines Network tool.

RESULTS

278 studies were included (80.6% cohort studies and 92.8% from North America). 7.9% were considered high-quality studies, while 23.0% were considered high risk of bias and inadmissible. The mean days until symptom free was 14.0 days (95% CI: 12.7, 15.4; I²=98.0%). The mean days until RTL was 8.3 (95% CI: 5.6, 11.1; I²=99.3%), with 93% of athletes having a full RTL by 10 days without new academic support. The mean days until RTS was 19.8 days (95% CI: 18.8, 20.7; I²=99.3%), with high heterogeneity between studies. Several measures define and track recovery, with initial symptom burden remaining the strongest predictor of longer days until RTS. Continuing to play and delayed access to healthcare providers were associated with longer recovery. Premorbid and postmorbid factors (eg, depression/anxiety, migraine history) may modify recovery time frames. Though point estimates suggest that female sex or younger age cohorts take longer to recover, the heterogeneity of study designs, outcomes and overlap in CIs with male sex or older age cohorts suggests that all have similar recovery patterns.

CONCLUSION

Most athletes have full RTL by 10 days but take twice as long for an RTS.

PROSPERO REGISTRATION NUMBER

CRD42020159928.

Update on Pediatric Mild Traumatic Brain Injury in Rural and Underserved Regions: A Global Perspective

BACKGROUND

Mild traumatic brain injury (MTBI) causes morbidity and disability worldwide. Pediatric patients are uniquely vulnerable due to developmental and psychosocial factors. Reduced healthcare access in rural/underserved communities impair management and outcome. A knowledge update relevant to current gaps in care is critically needed to develop targeted solutions.

METHODS

The National Library of Medicine PubMed database was queried using comprehensive search terms (("mild traumatic brain injury" or "concussion") and ("rural" or "low-income" or "underserved") and ("pediatric" or "child/children")) in the title, abstract, and Medical Subject Headings through December 2022. Fifteen articles on rural/underserved pediatric MTBI/concussion not covered in prior reviews were examined and organized into four topical categories: epidemiology, care practices, socioeconomic factors, and telehealth.

RESULTS

Incidences are higher for Individuals in rural regions, minorities, and those aged 0-4 years compared to their counterparts, and are increasing over time. Rural healthcare utilization rates generally exceed urban rates, and favor emergency departments (vs. primary care) for initial injury assessment. Management guidelines require customization to resource-constrained settings for implementation and adoption. Decreased community recognition of the seriousness of injury is a consensus challenge to care provision by clinicians. Low parental education and income were correlated with decreased MTBI knowledge and worse outcome. Telehealth protocols for triage/consultation and rehabilitation were feasible in improving care delivery to rural and remote settings.

CONCLUSIONS

Pediatric MTBI/concussion patients in rural/underserved regions experience increased risks of injury, geographic and financial healthcare barriers, and poorer outcomes. Globally, under-reporting of injury has hindered epidemiological understanding. Ongoing MTBI education should be implemented for rural caregivers, schools, and low-income populations to improve community awareness. Telehealth can improve care delivery across acuity settings, and warrants judicious inclusion in triage and treatment protocols.

'If in Doubt, Sit Them Out': How Long to Return to Elite Cycling Competition following a Sports-Related Concussion (SRC)?

INTRODUCTION

A concussion or sports-related concussion (SRC) is a traumatic brain injury induced by biomechanical forces. After a SRC diagnosis is made, a concussed individual must undergo a period away from competition while they return to their baseline level of functioning. The Union Cycliste Internationale (UCI) currently recommend a minimum of 6 days restriction from competitive cycling following a SRC but there is a growing feeling amongst those involved in brain injury research that this period is too short. Therefore, how much time should cyclists be removed from competitive sporting action following a SRC?

AIMS

To review the time out of competition following the diagnosis of a SRC for elite cyclists within British Cycling (BC).

METHODS

All medical records for elite cyclists within BC were audited for diagnoses of "concussion" or "sports-related concussions" from January 2017 until September 2022. The days out of competition following the concussion until ready to compete again (that is, returned to full training) was then calculated. All diagnoses and management of SRC were undertaken by the medical team at BC and in-keeping with current international guidelines.

RESULTS

Between January 2017 and September 2022, there were 88 concussions diagnosed, 54 being males and 8 in para-athletes. The median duration for time out of competition for all concussions was 16 days. There was no statistical difference between males (median 15.5 days) and females (median 17.5 days) for time out of competition (p-value 0.25). The median duration out of competition following a concussion for able-bodied athletes was 16 (80 athletes) compared to 51 days (8 athletes) in para-cyclists, which was not statistically different (p-value 0.39).

CONCLUSIONS

This is the first study to report SRC concussion recovery times in elite cycling, including para-athletes. Between January 2017 and September 2022, there were 88 concussions diagnosed at BC and the median duration for time out of competition for all concussions was 16 days. There was no statistically significant difference in recovery times between male and females and para- and able-bodied athletes. This data should be used to help establish minimum withdrawal times post-SRC for elite cycling participation and we call on the UCI to review this data when establishing SRC protocols for cycling, with further research required in para-cyclists.

Hierarchical clustering of prolonged post-concussive symptoms after 12 months: symptom-centric analysis and association with functional impairments

BACKGROUND

Following a concussion, approximately 15% of individuals experience persistent symptoms that can lead to functional deficits. However, underlying symptom-clusters that persist beyond 12 months have not been adequately characterized, and their relevance to functional deficits are unclear. The aim of this study was to characterize the underlying clusters of prolonged post-concussive symptoms lasting more than 12 months, and to investigate their association with functional impairments.

METHODS

Although hierarchical clustering is ideally suited in evaluating subjective symptom severities, it has not been applied to the Rivermead Post-Concussion Questionnaire (RPQ). The RPQ and functional impairments questions were administered via a smartphone application to 445 individuals who self-reported prolonged post-concussive symptoms. Symptom-clusters were obtained using agglomerative hierarchical clustering, and their association with functional deficits were investigated with sensitivity analyses, and corrected for multiple comparisons.

RESULTS

Five symptom-clusters were identified: headache-related, sensitivity to light and sound, cognitive, mood-related, and sleep-fatigue. Individuals with more severe RPQ symptoms were more likely to report functional deficits (p < 0.0001). Whereas the headache and sensitivity clusters were associated with at most one impairment, at-least-mild sleeping difficulties and fatigue were associated with four, and moderate-to-severe cognitive difficulties with five (all p < 0.01).

CONCLUSIONS

Symptom-clusters may be clinically useful for functional outcome stratification for targeted rehabilitation therapies. Further studies are required to replicate these findings in other cohorts and questionnaires, and to ascertain the effects of symptomatic intervention on functional outcomes.

Findings from a Randomized Controlled Trial of SMART: An EHealth Intervention for Mild Traumatic Brain Injury

OBJECTIVE

The aim of this study was to examine the efficacy of the SMART (Self-Management After Recent Traumatic brain injury) program and potential moderators.

METHODS

Parallel randomized controlled trial (ClinicalTrials.gov Identifier: NCT03498495) was conducted. Eligibility criteria included treatment for mild traumatic brain injury in the emergency department and age 11-18 years. Participants were assigned equally to SMART (n = 35) or usual care (UC; n = 36). SMART included symptom monitoring and online modules supporting the return to activities and symptom management. Coping and quality of life (QoL) (primary outcomes) and post-concussive symptoms (secondary outcome) were assessed at baseline and weekly for 4 weeks.

RESULTS

Groups did not differ in coping, QoL, or return to pre-injury symptom levels at any time point. Problem-focused engagement (PFE) moderated group differences over time (p = .02). At high PFE, UC participants reported lower QoL at time 1 (effect size [ES] = 0.60); SMART participants did not report a decline at any point. At low PFE, SMART participants reported declining QoL from pre-injury to time 1 (ES = 0.68), whereas UC participants reported an increase from time 1 to 3 (ES = 0.56). PFE also moderated group differences on the Health and Behavior Inventory (HBI) cognitive (p = .02) and somatic symptom scales (p = .05). At high PFE, SMART participants reported a more rapid return to pre-injury levels than UC participants (p = .05). Resilience also moderated group differences in QoL and HBI cognitive recovery.

CONCLUSION

Effectiveness of the SMART app varied based on preinjury coping styles and resilience, underscoring the potential need to tailor treatments to individual characteristics.

Changes in sport-related concussion and traumatic brain injury in New Zealand during the first two years of the COVID-19 pandemic

OBJECTIVES

To quantify changes in sport-related concussion and traumatic brain injury claims in New Zealand during the first two years of the COVID-19 pandemic (i.e., 2020 and 2021).

DESIGN

Population-based cohort study.

METHODS

This study included all new sport-related concussion and traumatic brain injury claims that were registered with the Accident Compensation Corporation in New Zealand during 1 January 2010 to 31 December 2021. Annual sport-related concussion and traumatic brain injury claim rates per 100,000 population from 2010 to 2019 were used to fit autoregressive integrated moving average models, from which forecast estimates with 95 % prediction intervals for 2020 and 2021 were derived and compared against corresponding observed values to obtain estimates of absolute and relative forecast errors.

RESULTS

Sport-related concussion and traumatic brain injury claim rates were 30 % and 10 % lower than forecasted in 2020 and 2021, respectively, equating to an estimated total of 2410 fewer sport-related concussion and traumatic brain injury claims during the two-year period.

CONCLUSIONS

There was a large reduction in sport-related concussion and traumatic brain injury claims in New Zealand during the first two years of the COVID-19 pandemic. These findings highlight the need for future epidemiological studies examining temporal trends of sport-related concussion and traumatic brain injury to account for the impact of the COVID-19 pandemic.

Current Use and Future Considerations for Concussion Telemedicine Healthcare in Canada

OBJECTIVE

To examine the use of telemedicine among Canadian concussion providers and clinics before and after the COVID-19 pandemic onset and identify barriers and facilitators for future use.

METHODS

Ninety-nine concussion clinics and healthcare providers across Canada that offered one or more clinical concussion-related service were identified using standardized online searches and approached to complete a cross-sectional online survey.

RESULTS

Thirty clinics or providers completed the survey and two completed subsections of the survey (response rate of 32.3%). Only 28.1% of respondents indicated that they used telemedicine to provide care prior to the COVID-19 pandemic. Providers most commonly using telemedicine prior to the pandemic were occupational therapists and physicians, while the most commonly used services were in-person videoconferencing and eConsultation. Most respondents (87%) indicated their clinic's use of telemedicine changed following the onset of the COVID-19 pandemic including new use of in-person video-conferencing, telephone calls, and eConsultation. Ninety-three percent indicated that they would consider using telemedicine to provide care to their concussion patients once the pandemic was over. Barriers needed to be overcome to facilitate use or greater use of telemedicine-based services were the inability to conduct a complete physical examination, lack of appropriate reimbursement, lack of start-up, and maintenance funding and medico-legal risk.

CONCLUSION

Telemedicine was used by a minority of Canadian concussion clinics and providers prior to the COVID-19 pandemic but was rapidly adopted by many facilities. This study provides important insight into the factors that must be considered to optimize use of telemedicine in concussion care in the future.

Sex-specific differences in resting-state functional brain activity in pediatric concussion

Pediatric concussion has a rising incidence and can lead to long-term symptoms in nearly 30% of children. Resting state functional magnetic resonance imaging (rs-fMRI) disturbances are a common pathological feature of pediatric concussion, though no studies have explicitly examined sex-differences with respect to this outcome, precluding a sex-specific understanding of the functional neuropathology of pediatric concussion. Therefore, we performed a secondary data analysis of rs-fMRI data collected on children with concussion (n = 29) recruited from in a pediatric hospital setting, with greater than 12:1 matched control data accessed from the open-source ABIDE-II database. Seed-based and region of interest (ROI) analyses were used to examine sex-based rs-fMRI differences; threshold-free cluster enhancement (TFCE) and a family-wise error (FWE) corrected p-values were used to identify significantly different clusters. In comparing females with concussion to healthy females, groupwise differences were observed irrespective of seed selected. Notably, we observed (in order of largest effect) hypo-connectivity between the anterior cingulate cortex of the salience network and the thalamus and precuneus (TFCE = 1473.5, p-FWE < 0.001) and the cingulate gyrus (TFCE = 769.3, p-FWE = 0.009), and the seed (posterior cingulate cortex (PCC)) of the default mode network and the paracingulate gyrus (TFCE = 1275.7, p-FWE  < 0.001), occipital pole right (TFCE = 1045.0, p-FWE = 0.001), and sub-callosal cortex (TFCE = 844.9, p-FWE = 0.005). Hyper-connectivity was observed between the salience network seed and the cerebellum (TFCE = 1719.3, p-FWE < 0.001) and the PCC and the thalamus (TFCE = 1198.3, p-FWE < 0.001), cuneal cortex (1070.9, p-FWE = 0.001), and lateral occipital cortex left (TFCE = 832.8, p-FWE = 0.006). ROI analyses showed 10 and 5 significant clusters of hypo- and hyper-connectivity in females, respectively. Only one cluster of difference was found between males with concussion and healthy males on seed-based analyses, and 3 clusters on ROI analyses. There are alterations in rs-fMRI in females with concussion at one-month post-injury that are minimally present in males, which provides further evidence that recovery timelines in pediatric concussion may differ by sex.

Return to work following mild traumatic brain injury: Psychological and cognitive factors in a litigating sample in the post acute stage of recovery

The purpose of this study was to investigate return to work (RTW) rates following a single uncomplicated mild Traumatic Brain Injury (mTBI) in the post-acute stage in the context of active litigation. More specifically, we sought to determine what psychological and/or cognitive factors predict a RTW after mTBI. Archival data were obtained from a random sample of litigating patients (n = 125; 54% female; mean age: 42.96 (SD = 12.74) who were referred to a private practice for a neuropsychological examination regarding their disability status following a single uncomplicated mTBI. A hierarchical regression analysis was used to assess the predictive value of emotional symptoms and cognition with respect to RTW status. Approximately 50% of the sample did not RTW. Attentional deficits (rs = -0.248) and depressive symptoms (rs = 0.248) were significantly associated with RTW. A hierarchical regression analysis found that depressive symptoms (p < .05) were associated with RTW outcomes. These findings suggest that individuals with increased depressive symptoms are more likely to demonstrate poor RTW outcomes in the post-acute stages of mTBI. These results are of interest to clinicians as they underscore the importance of screening and early intervention for depressive symptoms following a single uncomplicated mTBI in the post-acute stages in litigating samples.

Efficacy of aerobic exercise following concussion: a narrative review

Concussion is a type of mild traumatic brain injury which results in symptoms within the physical, cognitive, emotional, and sleep domains. Historically, guidelines established by expert opinion have recommended rest during the initial stages of recovery following a concussion until symptom resolution. However, recent recommendations have shifted to advise an initial period of 24-48 h of rest immediately following concussion with the gradual introduction of light-to-moderate intensity aerobic exercise thereafter. Given the relatively recent transition in recommendations, the aim of this review is to provide an overview of the current literature on the efficacy of aerobic exercise following concussion. The current literature is limited to studies assessing the impact of standardized aerobic exercise following concussion. Upon review, literature suggests participating in aerobic exercise below the point of symptom exacerbation is safe in both the acute and chronic post-concussion symptom stages of recovery and does not delay time to medical clearance. Future large-scale randomized controlled trials assessing the impact of aerobic exercise and differences between males and females would help support the current evidence suggesting aerobic exercise could improve time to recovery following concussion and identify any sex differences in response. As well, future studies with the purpose of identifying optimal aerobic exercise volume and intensity in the treatment of concussion could improve the specificity of the current guidelines.

The importance of screening for functional neurological disorders in patients with persistent post-concussion symptoms

BACKGROUND

Functional neurological disorder (FND) may commonly co-occur with persistent symptoms following a psychological trauma or physical injury such as concussion.

OBJECTIVE

To explore the occurrence of FND in a population with persistent post-concussion symptoms (PPCS) and the associations between FND and depression as well as anxiety in participants with PPCS.

METHODS

Sixty-three individuals with PPCS presenting to a specialized brain injury clinic completed the following questionnaires: screening for somatoform disorder conversion disorder subscale (SOM-CD), Rivermead post-concussion symptom questionnaire (RPQ), patient health questionnaire-9 (PHQ-9), and generalized anxiety disorder questionnaire- 7 (GAD-7). Both multiple linear regression and logistic regression were conducted to evaluate the relationship between questionnaires and adjust for covariates.

RESULTS

We found that total RPQ score (βˆ= 0.27; 95% CI = [0.16, 0.38]), GAD-7 score (βˆ= 0.71; 95% CI = [0.50, 0.92]) and PHQ-9 score (βˆ= 0.54; 95% CI = [0.32, 0.76]) were positively associated with SOM-CD score individually, after consideration of other covariates. Participants meeting the criteria for severe FND symptoms were 4.87 times more likely to have high PPCS symptom burden (95% CI = [1.57, 22.84]), 8.95 times more likely to have severe anxiety (95% CI = [3.31, 35.03]) and 4.11 times more likely to have severe depression symptom burden (95% CI = [1.77, 11.53]).

CONCLUSION

The findings of this study indicate an association between FND and post-concussion symptoms as well as an association between FND and symptoms of depression and anxiety in patients with PPCS. Patients with PPCS should be screened for FND to provide a more targeted treatment approach that includes somatic-focused interventions.

Follow-up visits after a concussion in the pediatric population: An integrative review

BACKGROUND

Concussions are a significant health issue for children and youth. After a concussion diagnosis, follow-up visits with a health care provider are important for reassessment, continued management, and further education.

OBJECTIVE

This review aimed to synthesize and analyse the current state of the literature on follow-up visits of children with a concussive injury and examine the factors associated with follow-up visits.

METHODS

An integrative review was conducted based on Whittemore and Knafl's framework. Databases searched included PubMed, MEDLINE, CINAHL, PsycINFO, and Google Scholar.

RESULTS

Twenty-four articles were reviewed. We identified follow-up visit rates, timing to a first follow-up visit, and factors associated with follow-up visits as common themes. Follow-up visit rates ranged widely, from 13.2 to 99.5%, but time to the first follow-up visit was only reported in eight studies. Three types of factors were associated with attending a follow-up visit: injury-related factors, individual factors, and health service factors.

CONCLUSION

Concussed children and youth have varying rates of follow-up care after an initial concussion diagnosis, with little known about the timing of this visit. Diverse factors are associated with the first follow-up visit. Further research on follow-up visits after a concussion in this population is warranted.

Concussion Public Policy in Elementary and High Schools in Ontario, Canada: A Cross-Sectional Survey to Examine Implementation Compliance, Barriers, and Facilitators

BACKGROUND

Concussion public policies have been developed to address the burden of concussions. The aim of the present study was to examine implementation compliance, barriers, and facilitators of Canada's first concussion public policy, Ontario's Policy/Program Memorandum 158: School Board Policies on Concussion (PPM158).

METHODS

An electronic survey was sent to 515 randomly selected elementary and high school principals across specific geographic, language, and publicly funded school types in Ontario. Data were analyzed using both qualitative and quantitative methods.

RESULTS

One hundred and thirty-five principals responded to the survey (26%). Concussion education was provided to teachers in 81% of schools, to students in 83%, and coaches in 79%. Additionally, 89% reported having a return-to-learn protocol in place and 90% reported having a return-to-play protocol. Implementation barriers included difficulties in providing concussion education to parents (42%), obtaining notes from physicians, and maintaining the volume of documentation. Eighty-seven percent of respondents believed that PPM158 improves student well-being.

CONCLUSIONS

Identified implementation barriers and facilitators can inform concussion policy practices to improve student well-being. We recommend: (1) an appointed concussion policy lead at each school, (2) electronic documentation, (3) determining the optimal education format to improve parent/guardian education, (4) fostering relationships between schools and health care professionals, and (5) student concussion education in every grade in Ontario schools.

Identification of Clinical Measures to Use in a Virtual Concussion Assessment: Protocol for a Mixed Methods Study

BACKGROUND

Workplace concussions can have a significant impact on workers. The impact of concussion symptoms, combined with challenges associated with clinical environments that are loud, bright, and busy, create barriers to conducting effective in-person assessments. Although the opportunity for remote care in rural communities has long been recognized, the COVID-19 pandemic has catalyzed the transition to virtual assessments and care into the mainstream. With this rapid shift, many clinicians have been completing remote assessments. However, the approaches and measures used in these assessments have not yet been standardized. Furthermore, the psychometric properties of the assessments when completed remotely using videoconference have not yet been documented.

OBJECTIVE

Through this mixed methods study, we aim to (1) identify the concussion assessment measures clinicians are currently using in person and are most relevant to the following 5 physical domains: neurological examination (ie, cranial nerve, coordination, motor, and sensory skills), cervical spine, vestibular, oculomotor, and effort assessment; (2) document the psychometric properties of the measures identified; (3) identify measures that appear feasible in a virtual context; and (4) identify practical and technical barriers or challenges, facilitators, and benefits to conducting or engaging in virtual concussion assessments.

METHODS

This study will follow a sequential mixed methods design using a survey and Delphi approach, working groups with expert clinicians, and focus groups with experienced clinicians and people living with concussions. Our target sample sizes are 50 clinicians for the Delphi surveys, 4 clinician-participants for the working group, and 5-7 participants for each focus group (roughly 6-10 total groups being planned with at least two groups consisting of people living with concussions). The results from this study will inform the decision regarding the measures that should be included in a virtual assessment tool kit to be tested in a future planned prospective evaluation study.

RESULTS

The study is expected to be completed by January 2023.

CONCLUSIONS

This mixed methods study will document the clinical measures that are currently used in person and will identify those that are most relevant to assessing the physical domains impacted by concussions. Potential feasibility of using these measures in a virtual context will be explored.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/40446.

Validity of algorithms for identifying mild traumatic brain injury in the French national emergency department database OSCOUR: a retrospective multicentre validation study protocol

INTRODUCTION

The French emergency department (ED) surveillance network OSCOUR transmits data on ED visits to Santé publique France (the national public health agency). As these data are collected daily and are almost exhaustive at a national level, it would seem relevant to use them for national epidemiological surveillance of mild traumatic brain injury (mTBI). This article presents the protocol of a planned study to validate algorithms for identifying mTBI in the OSCOUR database. Algorithms to be tested will be based on International Classification of Diseases (ICD)-10 codes.

METHODS AND ANALYSIS

We will perform a multicentre validation study of algorithms for identifying mTBI in OSCOUR. Different combinations of ICD-10 codes will be used to identify cases of mTBI in the OSCOUR database. A random sample of mTBI cases and non-cases will be selected from four EDs. Medical charts will serve as the reference standard to validate the algorithms. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the different algorithms, as well as their 95% CIs, will be calculated and compared.

ETHICS AND DISSEMINATION

The ethics committee of the French National Data Protection Authority (CNIL) approved this study (n° 921152, 1 August 2021). Results will be submitted to national and international peer-reviewed journals and presented at conferences dedicated to trauma and to methodologies for the construction and validation of algorithms.

School performance in youth after a concussion

Objective

This study aimed to identify school problems and levels of cognitive activity in youths aged 5-18 years with a concussion during the recovery stages of return to school (RTS).

Study Design

In a prospective cohort, participants completed in-person assessments at three time points: First Visit Post-injury, Symptom Resolution Visit, and Follow-Up Visit. These time points varied based on the participants' recovery progress. The post-concussion symptom scale (PCSS) and a cognitive activity scale were completed every 2 days until symptom resolution was achieved. Participants and their parents completed a school questionnaire detailing how their concussion had impacted their school learning/performance and their level of concern about their injury as well as the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT).

Results

Sixty-three percent (N = 44/70) of participants returned to school by the First Visit Post-injury (average 7.7 days following injury), and of these, 50% (N = 22) were experiencing school problems. Sixty-five participants (out of 70) returned to school at the Follow-Up Visit, and of these, 18% reported school problems. There was a significant difference in the school problems reported by parents and youth. At the First Visit Post-injury, the youth reported more problems (p = 0.02), and the In-Person Symptom Resolution Visit with parents reported more problems (p = 0.01). The cognitive activity score increased, while the PCSS score decreased from RTS Stage 1 to Stage 5.

Conclusions

This study identified that 50% of youth experienced school problems at the First Visit Post-injury, whereas only 18% reported school problems at the Follow-Up Visit. There is a significant difference in the perception of school problems reported by youth and their parents at different stages of recovery. The amount and complexity of cognitive activity increased with decreasing symptoms and increasing RTS stage. Findings can guide youth with a concussion and their parents in supporting a cautious return to school with accommodations. Healthcare providers and researchers can use this knowledge to better support youth in their return to school and understand the importance of gathering information from youth and their parents to gain the best insight into recovery.

R2Play development: Fostering user-driven technology that supports return-to-play decision-making following pediatric concussion

Objective

To design a multi-domain return-to-play assessment system (R2Play) for youth athletes with concussion.

Methods

The R2Play system was developed using an overarching user-centered approach, the Design Thinking Framework, and research activities included: 1) structured brainstorming within our research team, 2) interviews with clinician and youth sports coaches, 3) building a testable prototype, and 4) interface testing through cognitive walkthroughs with clinician partners.

Results

Clinician and coach participants provided feedback on the R2Play concept, which was integrated into the design process and provided future directions for research. Examples of feedback-driven design choices included reducing assessment time, increasing ecological validity by adding in background noise, and developing youth-friendly graphical results screens. Following refinement based on stakeholder feedback, the R2Play system was outlined in detail and a testable prototype was developed. It is made up of two parts: a clinician tablet, and a series of tablet "buttons" that display numbers and letters. Youth athletes run between the buttons to connect a "trail" in ascending alphanumeric order, 1-A-2-B, etc. Their performance across a series of levels of increasing difficulty is logged on the clinician tablet. Initial testing with five clinicians showed the system's interface to have excellent usability with a score of 81% (SD = 8.02) on the System Usability Scale.

Conclusion

Through this research, a prototype of the R2Play system was innovated and evaluated by clinician and coach stakeholders. Initial usability was excellent and directions for future iterations were highlighted. Outcomes suggest the potential benefits of using technologies to assist in complex clinical assessment, as well as utilizing a user-centered approach to design.

Traumatic brain injury: progress and challenges in prevention, clinical care, and research

Traumatic brain injury (TBI) has the highest incidence of all common neurological disorders, and poses a substantial public health burden. TBI is increasingly documented not only as an acute condition but also as a chronic disease with long-term consequences, including an increased risk of late-onset neurodegeneration. The first Lancet Neurology Commission on TBI, published in 2017, called for a concerted effort to tackle the global health problem posed by TBI. Since then, funding agencies have supported research both in high-income countries (HICs) and in low-income and middle-income countries (LMICs). In November 2020, the World Health Assembly, the decision-making body of WHO, passed resolution WHA73.10 for global actions on epilepsy and other neurological disorders, and WHO launched the Decade for Action on Road Safety plan in 2021. New knowledge has been generated by large observational studies, including those conducted under the umbrella of the International Traumatic Brain Injury Research (InTBIR) initiative, established as a collaboration of funding agencies in 2011. InTBIR has also provided a huge stimulus to collaborative research in TBI and has facilitated participation of global partners. The return on investment has been high, but many needs of patients with TBI remain unaddressed. This update to the 2017 Commission presents advances and discusses persisting and new challenges in prevention, clinical care, and research.

In LMICs, the occurrence of TBI is driven by road traffic incidents, often involving vulnerable road users such as motorcyclists and pedestrians. In HICs, most TBI is caused by falls, particularly in older people (aged ≥65 years), who often have comorbidities. Risk factors such as frailty and alcohol misuse provide opportunities for targeted prevention actions. Little evidence exists to inform treatment of older patients, who have been commonly excluded from past clinical trials—consequently, appropriate evidence is urgently required. Although increasing age is associated with worse outcomes from TBI, age should not dictate limitations in therapy. However, patients injured by low-energy falls (who are mostly older people) are about 50% less likely to receive critical care or emergency interventions, compared with those injured by high-energy mechanisms, such as road traffic incidents.

Mild TBI, defined as a Glasgow Coma sum score of 13–15, comprises most of the TBI cases (over 90%) presenting to hospital. Around 50% of adult patients with mild TBI presenting to hospital do not recover to pre-TBI levels of health by 6 months after their injury. Fewer than 10% of patients discharged after presenting to an emergency department for TBI in Europe currently receive follow-up. Structured follow-up after mild TBI should be considered good practice, and urgent research is needed to identify which patients with mild TBI are at risk for incomplete recovery.

The selection of patients for CT is an important triage decision in mild TBI since it allows early identification of lesions that can trigger hospital admission or life-saving surgery. Current decision making for deciding on CT is inefficient, with 90–95% of scanned patients showing no intracranial injury but being subjected to radiation risks. InTBIR studies have shown that measurement of blood-based biomarkers adds value to previously proposed clinical decision rules, holding the potential to improve efficiency while reducing radiation exposure. Increased concentrations of biomarkers in the blood of patients with a normal presentation CT scan suggest structural brain damage, which is seen on MR scanning in up to 30% of patients with mild TBI. Advanced MRI, including diffusion tensor imaging and volumetric analyses, can identify additional injuries not detectable by visual inspection of standard clinical MR images. Thus, the absence of CT abnormalities does not exclude structural damage—an observation relevant to litigation procedures, to management of mild TBI, and when CT scans are insufficient to explain the severity of the clinical condition.

Although blood-based protein biomarkers have been shown to have important roles in the evaluation of TBI, most available assays are for research use only. To date, there is only one vendor of such assays with regulatory clearance in Europe and the USA with an indication to rule out the need for CT imaging for patients with suspected TBI. Regulatory clearance is provided for a combination of biomarkers, although evidence is accumulating that a single biomarker can perform as well as a combination. Additional biomarkers and more clinical-use platforms are on the horizon, but cross-platform harmonisation of results is needed. Health-care efficiency would benefit from diversity in providers.

In the intensive care setting, automated analysis of blood pressure and intracranial pressure with calculation of derived parameters can help individualise management of TBI. Interest in the identification of subgroups of patients who might benefit more from some specific therapeutic approaches than others represents a welcome shift towards precision medicine. Comparative-effectiveness research to identify best practice has delivered on expectations for providing evidence in support of best practices, both in adult and paediatric patients with TBI.

Progress has also been made in improving outcome assessment after TBI. Key instruments have been translated into up to 20 languages and linguistically validated, and are now internationally available for clinical and research use. TBI affects multiple domains of functioning, and outcomes are affected by personal characteristics and life-course events, consistent with a multifactorial bio-psycho-socio-ecological model of TBI, as presented in the US National Academies of Sciences, Engineering, and Medicine (NASEM) 2022 report. Multidimensional assessment is desirable and might be best based on measurement of global functional impairment. More work is required to develop and implement recommendations for multidimensional assessment. Prediction of outcome is relevant to patients and their families, and can facilitate the benchmarking of quality of care. InTBIR studies have identified new building blocks (eg, blood biomarkers and quantitative CT analysis) to refine existing prognostic models. Further improvement in prognostication could come from MRI, genetics, and the integration of dynamic changes in patient status after presentation.

Neurotrauma researchers traditionally seek translation of their research findings through publications, clinical guidelines, and industry collaborations. However, to effectively impact clinical care and outcome, interactions are also needed with research funders, regulators, and policy makers, and partnership with patient organisations. Such interactions are increasingly taking place, with exemplars including interactions with the All Party Parliamentary Group on Acquired Brain Injury in the UK, the production of the NASEM report in the USA, and interactions with the US Food and Drug Administration. More interactions should be encouraged, and future discussions with regulators should include debates around consent from patients with acute mental incapacity and data sharing. Data sharing is strongly advocated by funding agencies. From January 2023, the US National Institutes of Health will require upload of research data into public repositories, but the EU requires data controllers to safeguard data security and privacy regulation. The tension between open data-sharing and adherence to privacy regulation could be resolved by cross-dataset analyses on federated platforms, with the data remaining at their original safe location. Tools already exist for conventional statistical analyses on federated platforms, however federated machine learning requires further development. Support for further development of federated platforms, and neuroinformatics more generally, should be a priority.

This update to the 2017 Commission presents new insights and challenges across a range of topics around TBI: epidemiology and prevention (section 1 ); system of care (section 2 ); clinical management (section 3 ); characterisation of TBI (section 4 ); outcome assessment (section 5 ); prognosis (Section 6 ); and new directions for acquiring and implementing evidence (section 7 ). Table 1 summarises key messages from this Commission and proposes recommendations for the way forward to advance research and clinical management of TBI.