Concussion Guidelines Step 2: Evidence for Subtype Classification

Team-based rehabilitation after mild traumatic brain injury - description of the clinical pathway

PURPOSE

Describe clinical practice, inter-disciplinary clinical pathway and core principles of care within a mild traumatic brain injury (mTBI) rehabilitation team.

METHODS

An observational study examined inter-disciplinary practice, nested within an observational trial investigating team-based mTBI rehabilitation. Data were collected to describe clinical service over 12 months. Activity data quantified clinical sessions per participant, mode of service delivery and content of sessions using custom-designed codes. The clinical team gathered narrative data to confirm the inter-disciplinary clinical pathway and individual discipline practice.

RESULTS

168 participants entered the rehabilitation program during the 12 months. A single Allied Health Screening Assessment identified patient priorities. Occupational Therapy (OT) and Physiotherapy (PT) provided the majority of clinical sessions; the team also comprised Social Work, Rehabilitation Medicine, Speech Pathology and Clinical Psychology. Telehealth was the most common service delivery mode (54%). Median session numbers per participant ranged 1-4 for all disciplines; mean/maximum occasions of service were highest for PT (6.9/44) and OT (6.8/39).

CONCLUSION

A small proportion of participants received much higher number of sessions, consistent with intractable issues after mTBI. High attendance rates indicate the predominantly telehealth-delivered model was feasible. The clinical approach included early prioritizing of discipline input and follow-up after discharge.

Heads up on concussion: Aboriginal and Torres Strait Islander peoples' knowledge and understanding of mild traumatic brain injury

ISSUE ADDRESSED

Concussion awareness and knowledge among Aboriginal and Torres Strait Islander peoples residing in Perth, Western Australia and factors preventing presentation at a health service for assessment after such an injury.

METHODS

Qualitative study with participants aged between 18 and 65 years. Recruitment was by Facebook advertising and snowball sampling. A semi-structured topic yarning guide was used to guide conversations through 1:1, multi-person or group yarns. Yarns were audio-recorded, transcribed and thematically analysed.

RESULTS

Twenty-four participants were recruited. A good knowledge of modes of concussion injury was identified in these participants. However, they identified difficulty differentiating this injury from other injuries or medical conditions. Multiple factors contributed to a reluctance to seek assessment and further management of a potential concussion. Multiple strategies to enhance education and presentation for assessment were suggested by participants.

CONCLUSIONS

Aboriginal and Torres Strait Islander-owned and led concussion education is the first step in enhancing understanding of this condition. Education must be coupled with improvements in the cultural safety of healthcare services, as without this, patients will continue to fail to present for assessment and management. SO WHAT?: It is recommended that concussion education focuses on the differentiation of concussion as a diagnosis from other injuries. Information regarding where and when to seek medical assessment is recommended, and this must be in a culturally safe environment. Typical recovery and potential sequelae must be explored, in programs led and devised by Aboriginal and Torres Strait Islander peoples engaged with the community for which the education is proposed.

Relationships between vestibular issues, noise sensitivity, anxiety and prolonged recovery from mild traumatic brain injury among adults: a scoping review

BACKGROUND

We investigated the extent of literature and findings on relationships between vestibular issues, noise sensitivity (NS), and anxiety. We were interested in how relationships among these factors impacted adults' recovery three months or more after mild traumatic brain injury (mTBI).

METHODS

We conducted a scoping review to evaluate the extent of evidence linking relationships between vestibular issues, NS and anxiety with recovery after mTBI. Data relating to study characteristics and key findings were extracted and used to inform a critical narrative synthesis of findings.

RESULTS

After screening and full-text review, we included two studies. Both studies considered the combination of vestibular issues, NS and anxiety and mTBI recovery. Vestibular issues, NS and anxiety were all significantly associated with one another and their presence was the strongest indicator that symptoms would extend beyond three-months after mTBI.

CONCLUSION

Few studies have focused on the relationships that vestibular issues, NS and anxiety have with one another and recovery after mTBI. Given the apparent strong relationships between these factors and prolonged recovery, we highlight this as an area warranting further investigation.

Clinical Trajectories of Comorbidity Associated With Military-Sustained Mild Traumatic Brain Injury: Pre- and Post-Injury

BACKGROUND AND OBJECTIVE

In the US military, traumatic brain injury (TBI) is of distinct importance, at home and in the deployed setting, and is considered a "signature injury of the wars in Afghanistan and Iraq." Since 2000, an estimated 468 424 service members (SMs) have been diagnosed with at least one TBI. We examined the clinical trajectories of a group of 18 comorbidities before and after a military-sustained mild TBI (mTBI).

METHODS

Without making assumptions on causality, a group of 18 conditions often co-occurring with mTBI were identified through literature review and TBI subject matter workgroup consensus. Using data from Military Health System Data Repository, we identified SMs whose first lifetime military mTBI occurred between October 1, 2016, and October 30, 2019. Correlation analyses were used to determine the linear relationship between comorbidities prior to and after mTBI diagnosis. Changes in the period prevalence of comorbidities was calculated.

RESULTS

We identified 42 018 SMs with a first lifetime military mTBI, of which 77.6% had at least one comorbidity. Identified SMs were mostly young (46.1% ages 18-24 years), male (81.4%), and White (64.1%). Up to 180 days prior to an mTBI, the most frequently identified conditions were sleep-related conditions (21.7%), headaches (19.4%), posttraumatic stress disorders (PTSDs) (17.8%), anxiety disorders (11.3%), and cervicogenic disorders (eg, cervicalgia) (10.9%). In the period following mTBI diagnosis, the prevalence of diagnosed conditions increased, especially for visual disturbances (327.2%), cognitive conditions (313.9%), vestibular conditions (192.6%), those related to headache (152.2%), and hearing (72.9%). Sleep-related conditions showed moderate positive correlation with a group of co-occurring conditions, led by cognitive conditions (ϕc = 0.50), anxiety disorders (ϕc = 0.42), PTSDs (ϕc =0.43), and headaches and related conditions (ϕc = 0.38).

CONCLUSION

Results indicate that caring for SMs with mild TBI requires a holistic approach, one that considers the complex nature of SM conditions, prior to sustaining their mTBI, as well as after injury. We found a complex correlation of conditions that suggest SMs with mTBI are undergoing a multifaceted experience, one that may require the development of a targeted multidimensional clinical practice recommendation and practice.

Serum calcitonin gene-related peptide in patients with persistent post-concussion symptoms, including headache: a cohort study

BACKGROUND

Calcitonin gene-related peptide (CGRP) plays an important role in migraine pathophysiology, and post-traumatic headache (PTH) frequently presents with migraine-like features. Despite several clinical similarities, few studies have explored CGRP in PTH and concussion. This study investigates serum CGRP levels in patients with persistent post-concussion symptoms (PPCS), including PTH.

METHODS

This cohort study was based on serum samples from individuals aged 18-30 years with PPCS who participated in a previously published randomized controlled trial of a non-pharmacological intervention. The primary outcome was serum CGRP concentrations, determined at baseline before randomization and at follow-up 7 months later, using an enzyme-linked immunosorbent assay (ELISA). CGRP levels at baseline were compared with healthy anonymous blood donors in the same age group.

RESULTS

Baseline serum samples were collected from 86 participants with PPCS. The participants were most often female (78%) and migraine-like headache was the most frequent headache phenotype (74%). Serum CGRP levels were higher in participants with PPCS than in 120 healthy individuals (median: 158.5 pg/mL vs. 76.3 pg/mL, p = 0.050). A stratified analysis revealed that females with PPCS had a fivefold higher median than healthy females (166.3 pg/mL vs. 32.1 pg/mL, p = 0.0006), while no differences were observed in males (p = 0.83). At follow-up, CGRP levels decreased with a median change of  - 1.3 pg/mL (95% confidence interval:  - 17.6-0, p = 0.024).

DISCUSSION

Elevated serum levels of CGRP in patients with PPCS and a decrease over time suggest an involvement of CGRP in PTH/PPCS. If confirmed in other studies, it could pave the way for CGRP-targeted therapies, which could have clinical significance.

Cognitive, Sleep-Arousal, Physical, and Affective Domain Scores on the Post-Concussion Symptom Scale: Added Utility in Detecting Symptom Elevations among Student-Athletes with a Remote History of Concussion

OBJECTIVE

The evaluation of self-reported symptoms is a standard component of concussion assessment and management. Clinicians typically evaluate a total symptom severity score rather than scores corresponding to specific symptom domains (i.e., cognitive, sleep-arousal, physical, and affective symptoms). This study examined (i) whether elevations in specific symptom domains would be missed when interpreting only the total symptom severity score and (ii) if a single symptom domain elevation was more common than having elevated symptoms across multiple domains.

METHOD

Adolescent student-athletes (N = 1,008) with concussion history (i.e., ≥6 months since last concussion) completed the Post-Concussion Symptom Scale (PCSS). The PCSS total score and cognitive, sleep-arousal, physical, and affective domain scores were calculated. To determine if symptoms were elevated, scores were compared to normative data matched on gender and pre-existing conditions, with scores considered elevated if they were ≥84th percentile. The frequency of total and domain score elevations were calculated and stratified by gender and number of prior concussions (i.e., 1 or ≥2 prior concussions).

RESULTS

Overall, 26% of student-athletes had an elevated symptom domain score without being elevated on the total score. The most common symptom presentation was to have a single elevated symptom domain (21%), followed by two (11%), three (8%), or four elevated domains (6%).

CONCLUSIONS

Interpreting PCSS symptom domains may be beneficial in detecting student-athletes with elevated symptoms following a remote concussion. Roughly a quarter of student-athletes have domain-specific symptom elevations that would be missed by interpreting the total score alone.

Dose-Response Effect of Mental Health Diagnoses on Concussion Recovery in Children and Adolescents

BACKGROUND

Pre-existing mental health diagnoses may contribute to greater emotional symptom burden and prolonged recovery after concussion.

HYPOTHESIS

Youth with pre-existing mental health diagnoses will have greater emotional symptom burden, greater risk for delayed return to exercise, and more prolonged recovery from concussion than those without those diagnoses.

STUDY DESIGN

Prospective cohort.

LEVEL OF EVIDENCE

Level 3.

METHODS

A prospective registry of youth concussion was examined for differences in emotional symptom burden after injury to develop a predictive risk model for prolonged recovery. The impact of individual and total number of pre-existing mental health diagnoses (0, 1, 2, and 3+) was assessed, and multivariable logistic regression was performed to identify factors associated with prolonged recovery.

RESULTS

Among a cohort of 3105 youth with concussion, those with a history of mental health diagnoses, in a dose-response fashion, had greater postinjury emotional symptom burden (7 emotional symptoms vs 4; P < 0.01), visio-vestibular dysfunction (65% abnormal vs 56% abnormal; P < 0.01), later return to symptom-limited exercise (23 vs 21 days; P < 0.01), and overall longer concussion recovery (38 days, interquartile range [IQR] 18, 80) versus 25 days (IQR 13, 54; P < 0.01). Boys with prolonged recovery after concussion had greater emotional symptom burden than girls (5 emotional symptoms vs 3; P < 0.01).

CONCLUSION

Pre-existing mental health diagnoses are associated with greater postinjury emotional symptom burden and longer concussion recovery in a dose-response fashion. Visiovestibular deficits and delayed return to exercise are also associated with pre-existing mental health diagnoses and prolonged recovery. Boys with prolonged recovery from concussion experience greater emotional symptom burden than girls.

CLINICAL RELEVANCE

Addressing pre-existing mental health diagnoses is essential to concussion management. Boys with prolonged recovery from concussion may particularly benefit from interventions to address their higher emotional symptom burden. Interventions, including a home visio-vestibular exercise program and symptom-limited exercise, may contribute to improving time to concussion recovery.

Symptoms Associated With Exercise Intolerance and Resting Heart Rate Following Mild Traumatic Brain Injury

OBJECTIVES

People may experience a myriad of symptoms after mild traumatic brain injury (mTBI), but the relationship between symptoms and objective assessments is poorly characterized. This study sought to investigate the association between symptoms, resting heart rate (HR), and exercise tolerance in individuals following mTBI, with a secondary aim to examine the relationship between symptom-based clinical profiles and recovery.

METHODS

Prospective observational study of adults aged 18 to 65 years who had sustained mTBI within the previous 7 days. Symptoms were assessed using the Post-Concussion Symptom Scale, HR was measured at rest, and exercise tolerance was assessed using the Buffalo Concussion Bike Test. Symptom burden and symptom-based clinical profiles were examined with respect to exercise tolerance and resting HR.

RESULTS

Data from 32 participants were assessed (mean age 36.5 ± 12.6 years, 41% female, 5.7 ± 1.1 days since injury). Symptom burden (number of symptoms and symptom severity) was significantly associated with exercise intolerance (P = .002 and P = .025, respectively). Physiological and vestibular-ocular clinical profile composite groups were associated with exercise tolerance (P = .001 and P = .014, respectively), with individuals who were exercise intolerant having a higher mean number of symptoms in each profile than those who were exercise tolerant. Mood-related and autonomic clinical profiles were associated with a higher resting HR (>80 bpm) (P = .048 and P = .028, respectively), suggesting altered autonomic response for participants with symptoms relating to this profile. After adjusting for age and mechanism of injury (sports- or non-sports-related), having a higher mood-related clinical profile was associated with persisting symptoms at 3 months postinjury (adjusted odds ratio = 2.08; 95% CI, 1.11-3.90; P = .013).

CONCLUSION

Symptom-based clinical profiles, in conjunction with objective measures such as resting HR and exercise tolerance, are important components of clinical care for those having sustained mTBI. These results provide preliminary support for the concept that specific symptoms are indicative of autonomic dysfunction following mTBI.

An Exploratory Analysis of Physical Examination Subtypes in Pediatric Athletes With Concussion

OBJECTIVE

Pediatric athletes with concussion present with a variety of impairments on clinical assessment and require individualized treatment. The Buffalo Concussion Physical Examination is a brief, pertinent clinical assessment for individuals with concussion. The purpose of this study was to identify physical examination subtypes in pediatric athletes with concussion within 2 weeks of injury that are relevant to diagnosis and treatment.

DESIGN

Secondary analysis of a published cohort study and clinician consensus.

SETTING

Three university-affiliated sports medicine centers.

PARTICIPANTS

Two hundred seventy children (14.9 ± 1.9 years).

INDEPENDENT VARIABLES

Orthostatic intolerance, horizontal and vertical saccades, smooth pursuits, vestibulo-ocular reflex, near-point convergence, complex tandem gait, neck range of motion, neck tenderness, and neck spasm.

MAIN OUTCOME MEASURES

Correlations between independent variables were calculated, and network graphs were made. k-means and hierarchical clustering were used to identify clusters of impairments. Optimal number of clusters was assessed. Results were reviewed by experienced clinicians and consensus was reached on proposed subtypes.

RESULTS

Physical examination clusters overlapped with each other, and no optimal number of clusters was identified. Clinician consensus suggested 3 possible subtypes: (1) visio-vestibular (horizontal and vertical saccades, smooth pursuits, and vestibulo-ocular reflex), (2) cervicogenic (neck range of motion and spasm), and (3) autonomic/balance (orthostatic intolerance and complex tandem gait).

CONCLUSIONS

Although we identified 3 physical examination subtypes, it seemed that physical examination findings alone are not enough to define subtypes that are both statistically supported and clinically relevant, likely because they do not include symptoms, assessment of mood or cognitive problems, or graded exertion testing.

Identification of Concussion Subtypes Based on Intrinsic Brain Activity

Importance

The identification of brain activity-based concussion subtypes at time of injury has the potential to advance the understanding of concussion pathophysiology and to optimize treatment planning and outcomes.

Objective

To investigate the presence of intrinsic brain activity-based concussion subtypes, defined as distinct resting state quantitative electroencephalography (qEEG) profiles, at the time of injury.

Design, Setting, and Participants

In this retrospective, multicenter (9 US universities and high schools and 4 US clinical sites) cohort study, participants aged 13 to 70 years with mild head injuries were included in longitudinal cohort studies from 2017 to 2022. Patients had a clinical diagnosis of concussion and were restrained from activity by site guidelines for more than 5 days, with an initial Glasgow Coma Scale score of 14 to 15. Participants were excluded for known neurological disease or history of traumatic brain injury within the last year. Patients were assessed with 2 minutes of artifact-free EEG acquired from frontal and frontotemporal regions within 120 hours of head injury. Data analysis was performed from July 2021 to June 2023.

Main Outcomes and Measures

Quantitative features characterizing the EEG signal were extracted from a 1- to 2-minute artifact-free EEG data for each participant, within 120 hours of injury. Symptom inventories and days to return to activity were also acquired.

Results

From the 771 participants (mean [SD] age, 20.16 [5.75] years; 432 male [56.03%]), 600 were randomly selected for cluster analysis according to 471 qEEG features. Participants and features were simultaneously grouped into 5 disjoint subtypes by a bootstrapped coclustering algorithm with an overall agreement of 98.87% over 100 restarts. Subtypes were characterized by distinctive profiles of qEEG measure sets, including power, connectivity, and complexity, and were validated in the independent test set. Subtype membership showed a statistically significant association with time to return to activity.

Conclusions and Relevance

In this cohort study, distinct subtypes based on resting state qEEG activity were identified within the concussed population at the time of injury. The existence of such physiological subtypes supports different underlying pathophysiology and could aid in personalized prognosis and optimization of care path.

A Common Data Element-Based Adjudication Process for mTBI Clinical Profiles: A Targeted Multidomain Clinical Trial Preliminary Study

INTRODUCTION

The primary purpose of this study was to examine the prevalence and percent agreement of clinician-identified mild traumatic brain injury (mTBI) clinical profiles and cutoff scores for selected Federal Interagency Traumatic Brain Injury Research common data elements (CDEs). A secondary purpose was to investigate the predictive value of established CDE assessments in determining clinical profiles in adults with mTBI.

MATERIALS AND METHODS

Seventy-one (23 males; 48 females) participants (M = 29.00, SD = 7.60, range 18-48 years) within 1-5 months (M = 24.20, SD = 25.30, range 8-154 days) of mTBI completed a clinical interview/exam and a multidomain assessment conducted by a licensed clinician with specialized training in concussion, and this information was used to identify mTBI clinical profile(s). A researcher administered CDE assessments to all participants, and scores exceeding CDE cutoffs were used to identify an mTBI clinical profile. The clinician- and CDE-identified clinical profiles were submitted to a multidisciplinary team for adjudication. The prevalence and percent agreement between clinician- and CDE-identified clinical profiles was documented, and a series of logistic regressions with adjusted odds ratios were performed to identify which CDE assessments best predicted clinician-identified mTBI clinical profiles.

RESULTS

Migraine/headache, vestibular, and anxiety/mood mTBI clinical profiles exhibited the highest prevalence and overall percent agreement among CDE and clinician approaches. Participants exceeding cutoff scores for the Global Severity Index and Headache Impact Test-6 assessments were 3.90 and 8.81 times more likely to have anxiety/mood and migraine/headache profiles, respectively. The Vestibular/Ocular Motor Screening vestibular items and the Pittsburgh Sleep Quality Index total score were predictive of clinician-identified vestibular and sleep profiles, respectively.

CONCLUSIONS

The CDEs from migraine/headache, vestibular, and anxiety/mood domains, and to a lesser extent the sleep modifier, may be clinically useful for identifying patients with these profiles following mTBI. However, CDEs for cognitive and ocular may have more limited clinical value for identifying mTBI profiles.

Visuo-vestibular and cognitive connections of the vestibular neuromatrix are conserved across age and injury populations

BACKGROUND AND PURPOSE

Given the prevalence of vestibular dysfunction in pediatric concussion, there is a need to better understand pathophysiological disruptions within vestibular and associated cognitive, affective, and sensory-integrative networks. Although current research leverages established intrinsic connectivity networks, these are nonspecific for vestibular function, suggesting that a pathologically guided approach is warranted. The purpose of this study was to evaluate the generalizability of the previously identified "vestibular neuromatrix" in adults with and without postconcussive vestibular dysfunction to young athletes aged 14-17.

METHODS

This retrospective study leveraged resting-state functional MRI data from two sites. Site A included adults with diagnosed postconcussive vestibular impairment and healthy adult controls and Site B consisted of young athletes with preseason, postconcussion, and postseason time points (prospective longitudinal data). Adjacency matrices were generated from preprocessed resting-state data from each sample and assessed for overlap and network structure in MATLAB.

RESULTS

Analyses indicated the presence of a conserved "core" network of vestibular regions as well as areas subserving visual, spatial, and attentional processing. Other vestibular connections were also conserved across samples but were not linked to the "core" subnetwork by regions of interest included in this study.

CONCLUSIONS

Our results suggest that connections between central vestibular, visuospatial, and known intrinsic connectivity networks are conserved across adult and pediatric participants with and without concussion, evincing the significance of this expanded, vestibular-associated network. Our findings thus support this network as a workable model for investigation in future studies of dysfunction in young athlete populations.

Vestibular perceptual testing from lab to clinic: a review

Not all dizziness presents as vertigo, suggesting other perceptual symptoms for individuals with vestibular disease. These non-specific perceptual complaints of dizziness have led to a recent resurgence in literature examining vestibular perceptual testing with the aim to enhance clinical diagnostics and therapeutics. Recent evidence supports incorporating rehabilitation methods to retrain vestibular perception. This review describes the current field of vestibular perceptual testing from scientific laboratory techniques that may not be clinic friendly to some low-tech options that may be more clinic friendly. Limitations are highlighted suggesting directions for additional research.

Improving outcome after paediatric concussion: challenges and possibilities

The term concussion has permeated mainstream media and household vocabulary mainly due to awareness regarding the risks of concussion in professional contact sports, yet it occurs across a variety of settings and ages. Concussion is prevalent in infants, preschoolers, children, and adolescents, and is a common presentation or reason for referral to primary care providers, emergency departments, and specialised trauma clinics. Its broad range of symptoms and sequelae vary according to multiple individual, environmental, and clinical factors and can lead to health and economic burden. More than 20 years of research into risk factors and consequences of paediatric concussion has revealed as many questions as answers, and scientific work and clinical cases continue to expose its complexity and heterogeneity. In this Review, we present empirical evidence for improving outcome after paediatric concussion. We consider work pertaining to both sports and other injury mechanisms to provide a perspective that should be viewed as complementary to publications focused specifically on sports concussion. Contemporary challenges in prevention, diagnosis, prognosis, and intervention are discussed alongside pathways and future directions for improving outcome.

Association Between Symptom Cluster Endorsement at Initiation of a Graduated Return-to-Activity Protocol and Time to Return to Unrestricted Activity After Concussion in United States Service Academy Cadets

BACKGROUND

The endorsement of symptoms upon initiation of a graduated return-to-activity (GRTA) protocol has been associated with prolonged protocols. It is unclear whether there are specific symptom clusters affecting protocol durations.

PURPOSE

To describe the endorsement of specific concussion symptom clusters at GRTA protocol initiation and examine the association between symptom cluster endorsement and GRTA protocol duration.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

This study was conducted among cadets enrolled at 3 US service academies. Participants completed an evaluation upon GRTA protocol initiation. Participants endorsing symptoms were binarized based on 6 symptom clusters (cognitive, emotional, insomnia, physical, sensitivity, and ungrouped). The primary outcome of interest was GRTA protocol duration based on symptom cluster endorsement severity. Prevalence rates were calculated to describe symptom cluster endorsement. Kaplan-Meier survival estimates and univariate and multivariable Cox proportional hazards regression models were calculated for all 6 symptom clusters to estimate GRTA protocol duration while controlling for significant covariates.

RESULTS

Data from 961 concussed participants were analyzed. Of these, 636 participants were asymptomatic upon GRTA protocol initiation. Among the 325 symptomatic participants, the physical symptom cluster (80%) was most endorsed, followed by the cognitive (29%), insomnia (23%), ungrouped (19%), sensitivity (15%), and emotional (9%) clusters. Univariate results revealed a significant association between endorsing cognitive (hazard ratio [HR], 0.79; p = .001), physical (HR, 0.84; p < .001), insomnia (HR, 0.83; p = .013), sensitivity (HR, 0.70; p < .001), and ungrouped (HR, 0.75; p = .005) symptom clusters and GRTA protocol duration. Endorsing physical (HR, 0.84; p < .001) and sensitivity (HR, 0.81; p = .036) clusters maintained a significant association with GRTA protocol duration in the multivariable models.

CONCLUSION

Participants endorsing physical or sensitivity symptom clusters displayed GRTA protocols prolonged by 16% to 19% compared with participants not endorsing that respective cluster after controlling for significant covariates.

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.

Adolescents With More Oculomotor and Vestibular Signs of Sport-Related Concussion Benefit from Aerobic Exercise: An Exploratory Analysis

Abstract Early targeted heart rate (HR) aerobic exercise has been shown to reduce the duration of recovery from sport-related concussion (SRC) as well as the incidence of persistent post-concussive symptoms (PPCS). It is not known, however, if more severe oculomotor and vestibular presentations of SRC benefit from a prescription of aerobic exercise. The current study is an exploratory analysis of two published randomized controlled trials that compared aerobic exercise within 10 days of injury with a placebo-like stretching intervention. Combining the two studies yielded a larger sample size to stratify severity of concussion based on the number of abnormal physical examination signs present at the initial office evaluation, which were confirmed with self-reported symptoms and recovery outcomes. The most discriminant cut-off was between those who had ≤3 oculomotor and vestibular signs and those who had >3 signs. Aerobic exercise (hazard ratio = 0.621 [0.412, 0.936], p = 0.023) reduced recovery times even when controlling for site (hazard ratio = 0.461 [0.303, 0.701], p < 0.001), severity (hazard ratio = 0.528 [0.325, 0.858], p = 0.010) and the interaction term of intervention and severity (hazard ratio = 0.972 [0.495, 1.909], p = 0.935). Adolescents who presented with >3 signs and were assigned to the placebo-like stretching group had a PPCS incidence of 38%, which was the highest of all subgroups (aerobic exercise and ≤3 findings: 8%; stretching and ≤3 findings: 11%; aerobic exercise and >3 findings: 21%). This exploratory study provides pilot evidence that prescribed sub-symptom threshold aerobic exercise treatment early after SRC may be effective for adolescents with more oculomotor and vestibular physical examination signs and should be validated in future adequately powered trials.

Investigating the Student in Returning to Learn After Concussion: A Systematic Review and Meta-Analysis

PURPOSE

Examine concussion effects on academic outcomes, including student perspectives.

METHODS

This study included a systematic review and meta-analysis examining post-concussion school attendance, academic performance, perceptions of academic difficulty, and accommodations for students in elementary through college settings. The analysis considered pre- and post-injury factors, along with injury factors that contribute to post-concussion academic outcomes.

RESULTS

The systematic review showed that students with concussion miss more school days and perceive higher levels of academic difficulty, but results about academic performance varied. Meta-analysis yielded small concussion effects on school absence and academic performance and moderate effects on perceptions of academic difficulty. Female sex, older age, history of migraine, prior concussions, severe or persistent symptoms, vestibular-ocular motor, and cognitive disruptions are risk factors, but these moderators were not identified in the meta-analysis due to lack of effect sizes.

IMPLICATIONS FOR SCHOOL HEALTH POLICY, PRACTICE, AND EQUITY

This study confirmed negative concussion effects on academic absences, performance, and perceptions of academic difficulty. Identified contributing factors will guide future practices to support students returning to learn after concussion.

CONCLUSIONS

Negative impacts to academics from concussion may be amplified by complicating factors. Future investigations are needed to confirm risk factors and mitigating effects of early identification and post-injury supports.

Targeted multidomain intervention for complex mTBI: protocol for a multisite randomized controlled trial in military-age civilians

Background

Mild traumatic brain injury (mTBI) affects ~18,000 military personnel each year, and although most will recover in 3-4 weeks, many experience persisting symptoms and impairment lasting months or longer. Current standard of care for U.S. military personnel with complex mTBI involves initial (<48 h) prescribed rest, followed by behavioral (e.g., physical activity, sleep regulation, stress reduction, hydration, nutrition), and symptom-guided management. There is growing agreement that mTBI involves different clinical profiles or subtypes that require a comprehensive multidomain evaluation and adjudication process, as well as a targeted approach to treatment. However, there is a lack of research examining the effectiveness of this approach to assessing and treating mTBI. This multisite randomized controlled trial (RCT) will determine the effectiveness of a targeted multidomain (T-MD) intervention (anxiety/mood, cognitive, migraine, ocular, vestibular; and sleep, autonomic) compared to usual care (behavioral management) in military-aged civilians with complex mTBI.

Methods

This study employs a single-blinded, two-group repeated measures design. The RCT will enroll up to 250 military-aged civilians (18-49 yrs) with a diagnosed complex mTBI within 8 days to 6 months of injury from two concussion specialty clinics. The two study arms are a T-MD intervention and a usual care, behavioral management control group. All participants will complete a comprehensive, multidomain clinical evaluation at their first clinical visit. Information gathered from this evaluation will be used to adjudicate mTBI clinical profiles. Participants will then be randomized to either the 4-week T-MD or control arm. The T-MD group will receive targeted interventions that correspond to the patient's clinical profile (s) and the control group will receive behavioral management strategies. Primary outcomes for this study are changes from enrollment to post-intervention on the Neurobehavioral Symptom Inventory (NSI), Patient Global Impression of Change (PGIC), and functional near-infrared spectroscopy (fNIRS). Time to return to activity (RTA), and healthcare utilization costs will also be assessed.

Discussion

Study findings may inform a more effective approach to treat complex mTBI in military personnel and civilians, reduce morbidity, and accelerate safe return-to-duty/activity.

Ethics and dissemination

The study is approved by the University of Pittsburgh Institutional Review board and registered at clinicaltrials.gov. Dissemination plans include peer-reviewed publications and presentations at professional meetings.

Clinical Trial Registration

www.clinicaltrials.gov, identifier: NCT04549532.

What tests and measures accurately diagnose persisting post-concussive symptoms in children, adolescents and adults following sport-related concussion? A systematic review

OBJECTIVE

To determine what tests and measures accurately diagnose persisting post-concussive symptoms (PPCS) in children, adolescents and adults following sport-related concussion (SRC).

DESIGN

A systematic literature review.

DATA SOURCES

MEDLINE, Embase, PsycINFO, Cochrane Central Register of Controlled Trials, CINAHL and SPORTDiscus through March 2022.

ELIGIBILITY CRITERIA

Original, empirical, peer-reviewed findings (cohort studies, case-control studies, cross-sectional studies and case series) published in English and focused on SRC. Studies needed to compare individuals with PPCS to a comparison group or their own baseline prior to concussion, on tests or measures potentially affected by concussion or associated with PPCS.

RESULTS

Of 3298 records screened, 26 articles were included in the qualitative synthesis, including 1016 participants with concussion and 531 in comparison groups; 7 studies involved adults, 8 involved children and adolescents and 11 spanned both age groups. No studies focused on diagnostic accuracy. Studies were heterogeneous in participant characteristics, definitions of concussion and PPCS, timing of assessment and the tests and measures examined. Some studies found differences between individuals with PPCS and comparison groups or their own pre-injury assessments, but definitive conclusions were not possible because most studies had small convenience samples, cross-sectional designs and were rated high risk of bias.

CONCLUSION

The diagnosis of PPCS continues to rely on symptom report, preferably using standardised symptom rating scales. The existing research does not indicate that any other specific tool or measure has satisfactory accuracy for clinical diagnosis. Future research drawing on prospective, longitudinal cohort studies could help inform clinical practice.

Heterogeneity of persisting symptoms after sport-related concussion (SRC): exploring symptom subtypes and patient subgroups

This study aimed to explore the heterogeneity of persisting symptoms after sport-related concussion (SRC). We examined the structure of symptom subtypes within 163 patients with SRC (M = 16.7 weeks post-injury). Subsequently, we investigated the existence of subgroups of patients based on comparable configuration of co-occurring symptom subtypes. To explore factors that may contribute to the emergence of SRC patient subgroups, subgroups were compared on pre-injury (i.e., demographics and medical history), personality (Severity Indices of Personality Problems Short Form) and SRC characteristics (i.e., history of prior concussions, loss of consciousness and post-traumatic amnesia). To investigate the relevance of SRC subgrouping for clinical outcome, subgroups were compared on symptom severity (Sport Concussion Assessment Tool 5). The results provide empirical evidence for the existence of symptom subtypes, characterized as a: neurocognitive, fatigue, emotional, migraine and vestibular-ocular symptom subtype in patients with persisting SRC. Study results also showed evidence for the existence of SRC subgroups of patients with a comparable configuration of co-occurring prevailing symptom subtypes, including a neurocognitive-migraine, fatigue, migraine-emotional and neurocognitive-emotional subgroup. The subgroups differed on pre-injury, personality and SRC characteristics, suggesting that these factors may contribute to the emergence of specific SRC patient subgroups. The subgroups also differed in the severity of persisting symptoms, highlighting the clinical relevance of SRC subgrouping. These results support the idea that patient subgroups with persisting SRC with a comparable pattern of co-occurring symptom subtypes exists, which may require targeted prognosis, clinical management and treatment to optimize recovery.

Multicentre evaluation of anxiety and mood among collegiate student athletes with concussion

Objectives

Mental health problems are a premorbid and postinjury concern among college student athletes. Clinical phenotypes of anxiety and mood disruption are prevalent following mild traumatic brain injury, including concussion, a common sports injury. This work examined whether concussed student athletes with a history of mental health problems and higher symptoms of anxiety and mood disruption at baseline were more likely to have higher postinjury reports of mood and anxiety as well as prolonged resolution of postconcussive symptoms to near-baseline measures.

Methods

This was a retrospective cohort study of a multi-institutional database of standardised baseline and postinjury assessments among college student athletes. Anxiety/mood evaluation data among varsity college athletes from four institutions over 1 year were measured and compared at baseline and postconcussion recovery using descriptive statistics and multilevel/mixed-effects analysis.

Results

Data from 2248 student athletes were analysed, with 40.6% reporting at least one symptom of anxiety and/or mood disruption at baseline. Of the 150 distinct concussions, 94.7% reported symptoms of anxiety/mood disruption during recovery (recovery time=0-96 days). Higher anxiety/mood scores at baseline were significantly associated with higher scores following concussion (p<0.001). Recovery trajectories of anxiety/mood scores showed different patterns by sex and prolonged recovery.

Conclusion

Symptoms of anxiety and mood disruption are common at baseline among college student athletes. These students are at higher risk for symptomatology following injury, representing a screening cohort that may benefit from early counselling. Almost all student athletes will experience symptoms of anxiety and/or mood disruption following concussion.

Clusters of conditions among US service members diagnosed with mild TBI from 2017 through 2019

Background

Many US Military Service Members (SMs) newly diagnosed with mild Traumatic Brain Injury (mTBI) may exhibit a range of symptoms and comorbidities, making for a complex patient profile that challenges clinicians and healthcare administrators. This study used clustering techniques to determine if conditions co-occurred as clusters among those newly injured with mTBI and up to one year post-injury.

Methods

We measured the co-occurrence of 41 conditions among SMs diagnosed with mTBI within the acute phase, one or three months post-mTBI diagnosis, and chronic phase, one year post-mTBI diagnosis. Conditions were identified from the literature, clinical subject matter experts, and mTBI care guidelines. The presence of conditions were based on medical encounters recorded within the military health care data system. Through a two-step approach, we identified clusters. Principal component analysis (PCA) determined the optimal number of clusters, and hierarchical cluster analyses (HCA) identified the composition of clusters. Further, we explored how the composition of these clusters changed over time.

Results

Of the 42,018 SMs with mTBI, 23,478 (55.9%) had at least one condition of interest one-month post-injury, 26,831 (63.9%) three months post-injury, and 29,860 (71.1%) one year post injury. Across these three periods, six clusters were identified. One cluster included vision, cognitive, ear, and sleep disorders that occurred one month, three months, and one year post-injury. Another subgroup included psychological conditions such as anxiety, depression, PTSD, and other emotional symptoms that co-occurred in the acute and chronic phases post-injury. Nausea and vomiting symptoms clustered with cervicogenic symptoms one month post-injury, but later shifted to other clusters. Vestibular disorders clustered with sleep disorders and headache disorders one-month post-injury and included numbness and neuropathic pain one year post-injury. Substance abuse symptoms, alcohol disorders, and suicidal attempt clustered one year post-injury in a fifth cluster. Speech disorders co-occurred with headache disorders one month and one year post-injury to form a sixth cluster.

Conclusion

PCA and HCA identified six distinct subgroups among newly diagnosed mTBI patients during the acute and chronic phases post-injury. These subgroups may help clinicians better understand the complex profile of SMs newly diagnosed with mTBI.

The effects of augmenting traditional rehabilitation with audio biofeedback in people with persistent imbalance following mild traumatic brain injury

Complaints of non-resolving imbalance are common in individuals with chronic mild traumatic brain injury (mTBI). Vestibular rehabilitation therapy may be beneficial for this population. Additionally, wearable sensors can enable biofeedback, specifically audio biofeedback (ABF), and aid in retraining balance control mechanisms in people with balance impairments. In this study, we described the effectiveness of vestibular rehabilitation therapy with and without ABF to improve balance in people with chronic mTBI. Participants (n = 31; females = 22; mean age = 40.9 ± 11 y) with chronic (>3 months) mTBI symptoms of self-reported imbalance were randomized into vestibular rehabilitation with ABF (n = 16) or without ABF (n = 15). The intervention was a standard vestibular rehabilitation, with or without ABF, for 45 min biweekly for 6 weeks. The ABF intervention involved a smartphone that provided auditory feedback when postural sway was outside of predetermined equilibrium parameters. Participant's completed the Post-Concussion Symptom Scale (PCSS). Balance was assessed with the sensory organization test (SOT) and the Central Sensorimotor Integration test which measured sensory weighting, motor activation, and time delay with sway evoked by surface and/or visual surround tilts. Effect sizes (Hedge's G) were calculated on the change between pre-and post-rehabilitation scores. Both groups demonstrated similar medium effect-sized decreases in PCSS and large increases in SOT composite scores after rehabilitation. Effect sizes were minimal for increasing sensory weighting for both groups. The with ABF group showed a trend of larger effect sizes in increasing motor activation (with ABF = 0.75, without ABF = 0.22) and in decreasing time delay (with ABF = −0.77, without ABF = −0.52) relative to the without ABF group. Current clinical practice focuses primarily on sensory weighting. However, the evaluation and utilization of motor activation factors in vestibular rehabilitation, potentially with ABF, may provide a more complete assessment of recovery and improve outcomes.

Implementation and Adoption of Telerehabilitation for Treating Mild Traumatic Brain Injury

BACKGROUND AND PURPOSE

Multimodal physical therapy for mild traumatic brain injury (mTBI) has been shown to improve recovery. Due to the coronavirus disease-2019 (COVID-19) pandemic, a clinical trial assessing the timing of multimodal intervention was adapted for telerehabilitation. This pilot study explored feasibility and adoption of an in-person rehabilitation program for subacute mTBI delivered through telerehabilitation.

METHODS

Fifty-six in-person participants-9 males; mean (SD) age 34.3 (12.2); 67 (31) days post-injury-and 17 telerehabilitation participants-8 males; age 38.3 (12.7); 61 (37) days post-injury-with subacute mTBI (between 2 and 12 weeks from injury) were enrolled. Intervention included 8, 60-minute visits over 6 weeks and included subcategories that targeted cervical spine, cardiovascular, static balance, and dynamic balance impairments. Telerehabilitation was modified to be safely performed at home with minimal equipment. Outcome measures included feasibility (the number that withdrew from the study, session attendance, home exercise program adherence, adverse events, telerehabilitation satisfaction, and progression of exercises performed), and changes in mTBI symptoms pre- and post-rehabilitation were estimated with Hedges' g effect sizes.

RESULTS

In-person and telerehabilitation had a similar study withdrawal rate (13% vs 12%), high session attendance (92% vs 97%), and no adverse events. The telerehabilitation group found the program easy to use (4.2/5), were satisfied with care (4.7/5), and thought it helped recovery (4.7/5). The telerehabilitation intervention was adapted by removing manual therapy and cardiovascular portions and decreasing dynamic balance exercises compared with the in-person group. The in-person group had a large effect size (-0.94) in decreases in symptoms following rehabilitation, while the telerehabilitation group had a moderate effect size (-0.73).

DISCUSSION AND CONCLUSIONS

Telerehabilitation may be feasible for subacute mTBI. Limited ability to address cervical spine, cardiovascular, and dynamic balance domains along with underdosage of exercise progression may explain group differences in symptom resolution.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A392 ).

Post-Concussion Symptoms Rule: Derivation and Validation of a Clinical Decision Rule for Early Prediction of Persistent Symptoms after a Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) is a common problem. Depending on diagnostic criteria, 13 to 62% of those patients develop persistent post-concussion symptoms (PPCS). The main objective of this prospective multi-center study is to derive and validate a clinical decision rule (CDR) for the early prediction of PPCS. Patients aged ≥14 years were included if they presented to one of our seven participating emergency departments (EDs) within 24 h of an mTBI. Clinical data were collected in the ED, and symptom evolution was assessed at 7, 30 and 90 days post-injury using the Rivermead Post-Concussion Questionnaire (RPQ). The primary outcome was PPCS at 90 days after mTBI. A predictive model called the Post-Concussion Symptoms Rule (PoCS Rule) was developed using the methodological standards for CDR. Of the 1083 analyzed patients (471 and 612 for the derivation and validation cohorts, respectively), 15.6% had PPCS. The final model included the following factors assessed in the ED: age, sex, history of prior TBI or mental health disorder, headache in ED, cervical sprain and hemorrhage on computed tomography. The 7-day follow-up identified additional risk factors: headaches, sleep disturbance, fatigue, sensitivity to light, and RPQ ≥21. The PoCS Rule had a sensitivity of 91.4% and 89.6%, a specificity of 53.8% and 44.7% and a negative predictive value of 97.2% and 95.8% in the derivation and validation cohorts, respectively. The PoCS Rule will help emergency physicians quickly stratify the risk of PPCS in mTBI patients and better plan post-discharge resources.

Investigating the diagnostic accuracy of a paper-and-pencil and a computerized cognitive test battery for pediatric mild traumatic brain injury

OBJECTIVE

This study assessed classification accuracy of paper-and-pencil and computerized cognitive batteries at subacute (SA; 1-11 days) and early chronic (EC; ∼4 months) phases of pediatric mild traumatic brain injury (pmTBI). Two statistical approaches focused on single-subject performance (individual task scores, total impairments) were used to maximize clinical utility.

METHOD

Two hundred thirty-five pmTBI and 169 healthy controls (HC) participants aged 8-18 were enrolled, with a subset (190 pmTBI; 160 HC) returning for the EC visit. The paper-and-pencil battery included several neuropsychological tests selected from recommended common data elements, whereas computerized testing was performed with the Cogstate Brief Battery. Hierarchical logistic regressions (base model: Parental education and premorbid reading abilities; full model: Base model and cognitive testing variables) were used to examine sensitivity/specificity, with diagnosis as the dependent variable.

RESULTS

Number Sequencing and Cogstate One-Card Learning accuracy significantly predicted SA diagnosis (full model accuracy = 71.6%-71.7%, sensitivity = 80.6%-80.8%, specificity = 59.1%-59.6%), while only immediate recall was significant at EC visit (accuracy = 68.5%, sensitivity = 74.6%, specificity = 61.5%). Other measures (Letter Fluency, Cogstate Detection, and One-Card Learning accuracy) demonstrated higher proportions of impairment for pmTBI subacutely (pmTBI: 11.5%-19.8%; HC: 3.7%-6.1%) but did not improve classification accuracy. Evidence of multiple impairments across the entire testing battery significantly predicted diagnosis at both visits (full model accuracy = 66.2%-68.6%, sensitivity = 71.2%-78.9%, specificity = 54.3%-61.5%).

CONCLUSIONS

Current results suggest similar modest diagnostic accuracy for computerized and paper-and-pencil batteries across multiple pmTBI phases. Moreover, findings suggest the total number of impairments may be more clinically useful than any single test or cognitive domain in terms of diagnostic accuracy at both assessment points. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Exploring Vestibular Ocular Motor Screening in Adults With Persistent Complaints After Mild Traumatic Brain Injury

OBJECTIVE

The purpose of this study was to (1) explore differences in vestibular ocular motor screening (VOMS) symptoms between healthy adults and adults with persistent symptoms after mild traumatic brain injury (mTBI), and (2) explore the relationships between VOMS symptoms and other measures (self-reported vestibular symptoms, clinical measures of balance and gait, and higher-level motor ability tasks).

SETTING

Research laboratory setting.

PARTICIPANTS

Fifty-three persons with persistent symptoms (>3 weeks) following mTBI and 57 healthy controls were recruited. Eligibility for participation included being 18 to 50 years of age and free of medical conditions that may affect balance, with the exception of recent mTBI for the mTBI group.

DESIGN

Cross-sectional.

MAIN MEASURES

The primary outcomes were the VOMS symptom scores and near point of convergence (NPC) distance. Secondary outcomes included the Dizziness Handicap Inventory (DHI) total and subdomain scores, sway area, Functional Gait Analysis total score, gait speed, and modified Illinois Agility Task completion time, and Revised High-Level Mobility Assessment Tool total score.

RESULTS

The mTBI group reported more VOMS symptoms ( z range, -7.28 to -7.89) and a further NPC ( t = -4.16) than healthy controls (all P s < .001). DHI self-reported symptoms (total and all subdomain scores) were strongly associated with the VOMS symptom scores (rho range, 0.53-0.68; all P s < .001). No significant relationships existed between VOMS symptoms and other measures.

CONCLUSION

Significant group differences support the relevance of the VOMS for mTBI in an age-diverse sample with persistent symptoms. Furthermore, strong association with DHI symptoms supports the ability of the VOMS to capture vestibular complaints in this population.

Pathway of care for visual and vestibular rehabilitation after mild traumatic brain injury: a critical review

PRIMARY OBJECTIVE

To review the pathway to care for treatment and management of patients receiving visual and vestibular rehabilitation after mild traumatic brain injury (mTBI).

METHODS & PROCEDURES

English scientific peer-reviewed articles from PubMed, CINAHL, Embase, and PsycINFO between 2000 and 2020 were first screened by title and abstract, then those selected underwent full-text review and analysis.

MAIN OUTCOMES & RESULTS

The database search yielded 1640 results and after title and abstract review, 75 articles were selected for full-text screening, from which 8 were included in the qualitative synthesis. Current evidence includes a limited number of retrospective cohort studies and case studies.

CONCLUSIONS

Many patients with visual and vestibular deficits following mTBI do not receive rehabilitation services until months following their injury as there is no standardized pathway to care for patients for visual and vestibular rehabilitation. Barriers to establishing a standardized pathway are the lack of natural history data for visual and vestibular function following mTBI and the lack of randomized clinical trials establishing the efficacy of rehabilitation in patients following mTBI.

A window into eye movement dysfunction following mTBI: A scoping review of magnetic resonance imaging and eye tracking findings

Mild traumatic brain injury (mTBI), commonly known as concussion, is a complex neurobehavioral phenomenon affecting six in 1000 people globally each year. Symptoms last between days and years as microstructural damage to axons and neurometabolic changes result in brain network disruption. There is no clinically available objective biomarker to diagnose the severity of injury or monitor recovery. However, emerging evidence suggests eye movement dysfunction (e.g., saccades and smooth pursuits) in patients with mTBI. Patients with a higher symptom burden and prolonged recovery time following injury may show higher degrees of eye movement dysfunction. Likewise, recent advances in magnetic resonance imaging (MRI) have revealed both white matter tract damage and functional network alterations in mTBI patients, which involve areas responsible for the ocular motor control. This scoping review is presented in three sections: Section 1 explores the anatomical control of eye movements to aid the reader with interpreting the discussion in subsequent sections. Section 2 examines the relationship between abnormal MRI findings and eye tracking after mTBI based on the available evidence. Finally, Section 3 communicates gaps in our knowledge about MRI and eye tracking, which should be addressed in order to substantiate this emerging field.

Characteristics of concussion subtypes from a multidomain assessment

OBJECTIVE

The aim of this study was to analyze the best combination of clinical variables associated with concussion subtypes using a multidomain assessment comprising medical history; symptoms; and cognitive, ocular, and vestibular impairment in a cohort of patients presenting to a concussion specialty clinic.

METHODS

Adolescent patients (n = 293) completed demographics and medical history, Concussion Clinical Profiles Screening, Immediate Post-Concussion Assessment and Cognitive Testing, and vestibular ocular motor screening at their first visit (mean 7.6 ± 7.8 days postinjury) to a concussion specialty clinic. Each participant was adjudicated to have one or more subtype (anxiety/mood, cognitive, migraine, ocular, and vestibular) by a healthcare professional based on previously published criteria. A series of backward, stepwise logistic regressions were used to identify significant predictors of concussion subtypes, and predictive probabilities from the logistic regression models were entered into area under the receiver operating characteristic curve (AUC) models.

RESULTS

Each of 5 logistic regression models predicting primary subtypes accounted for 28%-50% of the variance (R2 = 0.28-0.50, p < 0.001) and included 2-8 significant predictors per model. Each of the models significantly differentiated the primary subtype from all other subtypes (AUC = 0.76-0.94, p < 0.001).

CONCLUSIONS

These findings suggest that each concussion subtype can be identified using specific outcomes from a multidomain assessment. Clinicians can employ such an approach to better identify and monitor recovery from subtypes as well as guide interventions.

Ambulatory Assessment in Concussion Clinical Care and Rehabilitation

Concussion is a mild traumatic brain injury that is characterized by a wide range of physical, emotional, and cognitive symptoms as well as neurocognitive, vestibular, and ocular impairments that can negatively affect daily functioning and quality of life. Clinical consensus statements recommend a targeted, clinical profile-based approach for management and treatment. This approach requires that clinicians utilize information obtained via a clinical interview and a multi-domain assessment battery to identify clinical profile(s) (e.g., vestibular, mood/anxiety, ocular, migraine, cognitive fatigue) and prescribe a corresponding treatment/rehabilitation program. Despite this comprehensive approach, the clinical picture can be limited by the accuracy and specificity of patient reports (which often conflate timing and severity of symptomology), as well as frequency and duration of exposure to symptom exacerbating environments (e.g., busy hallways, sitting in the back seat of a car). Given that modern rehabilitation programs leverage the natural environment as a tool to promote recovery (e.g., expose-recover approach), accurate characterization of the patient clinical profile is essential to improving recovery outcomes. Ambulatory assessment methodology could greatly benefit concussion clinical care by providing a window into the symptoms and impairments experienced by patients over the course of their daily lives. Moreover, by evaluating the timing, onset, and severity of symptoms and impairments in response to changes in a patient's natural environment, ambulatory assessments can provide clinicians with a tool to confirm clinical profiles and gauge effectiveness of the rehabilitation program. In this perspective report, we review the motivations for utilizing ambulatory assessment methodology in concussion clinical care and report on data from a pilot project utilizing smart phone-based, ambulatory assessments to capture patient reports of symptom severity, environmental exposures, and performance-based assessments of cognition for 7 days following their initial evaluation.

Temporal Differences in Concussion Symptom Factors in Adolescents following Sports-Related Concussion

OBJECTIVE

To evaluate temporal differences in concussion symptoms up to 30 days following a sports-related concussion.

STUDY DESIGN

Adolescent and young adult athletes (n = 782) were separated based on time since injury at presentation as Early (0-7 days; n = 321, age: 15.4 ± 1.9 years, 51.7% female), Middle (8-14 days; n = 281, age: 15.8 ± 2.2 years, 54.8% female), and Late (15-30 days; n = 180, age: 15.6 ± 1.8 years, 52.8% female). All participants completed the 22-item Post-Concussion Symptom Scale at first visit. A confirmatory factor analysis was completed separately for each time since injury cohort using a 4-component model reported previously.

RESULTS

The confirmatory factor analysis model fit was acceptable for Early, Middle, and Late (using cognitive-migraine-fatigue, affective, sleep, and somatic factors). Both affective (change = 0.30; P = .01; Cohen d = 0.30) and sleep (change = 0.51; P ≤ .001; Cohen d = 0.47) factors were significantly greater in the Late group compared with the Early, but not Middle, groups. The previously reported 4-factor symptom model, including cognitive-migraine-fatigue, affective, somatic, and sleep factors, was appropriate for adolescents up to 30 days' postinjury. However, adolescents who presented between 15 and 30 days' postinjury reported greater affective and sleep symptoms than those who presented within 1 week.

CONCLUSIONS

Clinicians should consider these temporal differences when evaluating concussion symptoms in adolescents, as greater affective and sleep symptoms can be predictive of prolonged recovery/persistent complications.

The Neuropsychiatric Approach to the Assessment of Patients in Neurology

Neuropsychiatry is a clinical neuroscience specialty focused on the evaluation and treatment of patients who present with symptoms at the intersection of neurology and psychiatry. Neuropsychiatrists assess and manage the cognitive, affective, behavioral, and perceptual manifestations of disorders of the central nervous system. Although fellowship training in behavioral neurology-neuropsychiatry exists in the United States and several other countries internationally, the need for neuropsychiatric expertise greatly outweighs the number of specialists in practice or training. This article serves as a primer for both neurologists and psychiatrists seeking to improve or refresh their knowledge of the neuropsychiatric assessment, including detailing aspects of the history-taking, physical exam, psychometric testing, and associated diagnostic work-up. In doing so, we urge the next generation of neurologists and psychiatrists to take on both the opportunity and challenge to work at the intersection of both clinical neuroscience specialties using an integrated neuropsychiatric perspective.

Cognitive-Communication Complaints and Referrals for Speech-Language Pathology Services Following Concussion

PURPOSE

Speech-language pathologists are increasingly being recognized as key members of concussion management teams. This study investigates whether self-report of communication problems postconcussion may be useful in identifying clients who could benefit from speech-language pathology services.

METHOD

Participants included 41 adolescents and adults from an outpatient specialty concussion clinic. All completed the La Trobe Communication Questionnaire (LCQ) at admission, and 23 repeated this measure at discharge. Participants were prospectively enrolled, with chart reviews providing demographic, injury, and medical factors. The analysis considered (a) communication complaints and resolution over time, including comparison to two previously published LCQ studies of typical adults and adults with and without traumatic brain injury (TBI); (b) the relationship between communication complaints, participant factors, and common concussion assessments; and (c) factors related to speech-language pathology service referral for rehabilitation.

RESULTS

At first visit, 12 of 41 participants (29%) reported communication problems, although 19 (46%) reported difficulty with greater than half of LCQ items. At a group level, compared to published reference data of both people with chronic mixed severity TBI and controls, participants in this study reported more problems at first visit with communication overall, as well as greater difficulty with the LCQ Initiation/Conversation Flow subscale. Partner Sensitivity subscale scores at first visit were also greater than published control data. LCQ subscale scores of Initiation/Conversation Flow and Partner Sensitivity decreased from first visit to last visit, demonstrating resolution over time. Only concussion symptom scales and not demographic, injury, or cognitive screenings were related to LCQ scores. The same two LCQ subscales, Initiation/Conversation Flow and Partner Sensitivity, predicted referral for speech-language pathology services, along with symptom scales and being injured due to motor vehicle crash.

DISCUSSION

A subset of people recovering from concussion report experiencing communication problems. Reporting of particular communication problems was related to referral for speech-language pathology rehabilitation services and may be useful in directing care after concussion.

Concussion Management Guidelines Neglect Auditory Symptoms

Tinnitus, noise sensitivity, and hearing difficulties are commonly reported secondary to head injury. These auditory deficits have been shown to negatively impact daily functioning, and yet, often go unnoticed by health care professionals. The purpose of this editorial is to explain why it is essential for clinical practice guidelines that address the management of patients who have experienced a head injury to incorporate assessment and rehabilitation of auditory symptoms.

Traumatic Brain Injury in Children: Glial fibrillary Acidic Protein and Clinical Outcomes

OBJECTIVES

Glial fibrillary acidic protein (GFAP) is a neuronal protein released after traumatic brain injury (TBI) and detectable in serum samples. GFAP correlates with symptom severity in adults and may be a marker of brain injury in children with milder symptoms or preverbal children.

METHODS

GFAP was examined in children with severe TBI (initial Glasgow Coma Scale score <8), with mild TBI (Glasgow Coma Scale score 14/15), and at 0 to 4 and at 10 to 14 days after TBI and was compared with healthy age-matched controls. Mechanism, time points from injury, and symptoms were recorded.

RESULTS

The study enrolled 208 children including 110 with TBI (n = 104 mild, 6 severe) and controls (n = 98). GFAP was higher in mild TBI than in controls and highest in the severe TBI cohort, with a maximum value at 6 hours from injury. Vomiting was significantly associated with higher GFAP levels, but no association was found with amnesia, loss of consciousness, and the Sports Concussion Assessment Tool. Children reporting >1-point changes from their preinjury functioning on the Post-Concussive Symptom Inventory had higher initial GFAP but not total Post-Concussive Symptom Inventory score changes.

CONCLUSIONS

GFAP identifies children with TBI, even at the milder end of the spectrum, and is strongly associated with postinjury vomiting. It may be a useful marker of pediatric TBI; however, sampling is time critical.

Neuropsychiatric Treatment for Mild Traumatic Brain Injury: Nonpharmacological Approaches

Postconcussive symptoms following mild traumatic brain injury (mTBI)/concussion are common, disabling, and challenging to manage. Patients can experience a range of symptoms (e.g., mood disturbance, headaches, insomnia, vestibular symptoms, and cognitive dysfunction), and neuropsychiatric management relies heavily on nonpharmacological and multidisciplinary approaches. This article presents an overview of current nonpharmacological strategies for postconcussive symptoms including psychoeducation; psychotherapy; vestibular, visual, and physical therapies; cognitive rehabilitation; as well as more novel approaches, such as neuromodulation. Ultimately, treatment and management of mTBI should begin early with appropriate psychoeducation/counseling, and be tailored based on core symptoms and individual goals.

Behavioral and Cognitive Aspects of Concussion

PURPOSE OF REVIEW

This review provides the reader with an overview of concussion and mild traumatic brain injury (TBI). Key aspects of the pathophysiology, signs, and symptoms, treatment and rehabilitation, and recovery from concussion/mild TBI are reviewed with an emphasis on the variety of factors that may contribute to cognitive concerns following injury.

RECENT FINDINGS

Concussion remains a clinical diagnosis based on symptoms that occur in the immediate aftermath of an applied force and in the hours, days, and weeks thereafter. Although advances have been made in advanced diagnostics, including neuroimaging and fluid biomarkers in hopes of developing objective indicators of injury, such markers currently lack sufficient specificity to be used in clinical diagnostics. The symptoms of concussion are heterogeneous and may be seen to form subtypes, each of which suggests a targeted rehabilitation by the interdisciplinary team. Although the majority of patients with concussion recover within the first 30 to 90 days after injury, some have persistent disabling symptoms. The concept of postconcussion syndrome, implying a chronic syndrome of injury-specific symptoms, is replaced by a broader concept of persistent symptoms after concussion. This concept emphasizes the fact that most persistent symptoms have their basis in complex somatic, cognitive, psychiatric, and psychosocial factors related to risk and resilience. This framework leads to the important conclusion that concussion is a treatable injury from which nearly all patients can be expected to recover.

SUMMARY

Concussion/mild TBI is a significant public health problem in civilian, military, and organized athletic settings. Recent advances have led to a better understanding of underlying pathophysiology and symptom presentation and efficacious treatment and rehabilitation of the resulting symptoms. An interdisciplinary team is well-positioned to provide problem-oriented, integrated care to facilitate recovery and to advance the evidence base supporting effective practice in diagnosis, treatment, and prevention.

Evolution and Impact of the Brain Trauma Foundation Guidelines

The Brain Trauma Foundation (BTF) Guidelines for the Management of Severe Head Injury were the first clinical practice guidelines published by any surgical specialty. These guidelines have earned a reputation for rigor and have been widely adopted around the world. Implementation of these guidelines has been associated with a 50% reduction in mortality and reduced costs of patient care. Over their 25-yr history the traumatic brain injury (TBI) guidelines have been expanded, refined, and made increasingly more rigorous in conjunction with new clinical evidence and evolving methodologic standards. Here, we discuss the history and accomplishments of BTF guidelines for TBI as well as their limitations. We also discuss planned changes to future TBI guidelines intended to increase their utility and positive impact in an evolving medical landscape. Perhaps the greatest limitation of TBI guidelines now is the lack of high-quality clinical research as well as novel diagnostics and treatments with which to generate substantially new recommendations.

Machine Learning for Subtyping Concussion Using a Clustering Approach

Background: Concussion subtypes are typically organized into commonly affected symptom areas or a combination of affected systems, an approach that may be flawed by bias in conceptualization or the inherent limitations of interdisciplinary expertise.

Objective: The purpose of this study was to determine whether a bottom-up, unsupervised, machine learning approach, could more accurately support concussion subtyping.

Methods: Initial patient intake data as well as objective outcome measures including, the Patient-Reported Outcomes Measurement Information System (PROMIS), Dizziness Handicap Inventory (DHI), Pain Catastrophizing Scale (PCS), and Immediate Post-Concussion Assessment and Cognitive Testing Tool (ImPACT) were retrospectively extracted from the Advance Concussion Clinic's database. A correlation matrix and principal component analysis (PCA) were used to reduce the dimensionality of the dataset. Sklearn's agglomerative clustering algorithm was then applied, and the optimal number of clusters within the patient database were generated. Between-group comparisons among the formed clusters were performed using a Mann-Whitney U test.

Results: Two hundred seventy-five patients within the clinics database were analyzed. Five distinct clusters emerged from the data when maximizing the Silhouette score (0.36) and minimizing the Davies-Bouldin score (0.83). Concussion subtypes derived demonstrated clinically distinct profiles, with statistically significant differences (p < 0.05) between all five clusters.

Conclusion: This machine learning approach enabled the identification and characterization of five distinct concussion subtypes, which were best understood according to levels of complexity, ranging from Extremely Complex to Minimally Complex. Understanding concussion in terms of Complexity with the utilization of artificial intelligence, could provide a more accurate concussion classification or subtype approach; one that better reflects the true heterogeneity and complex system disruptions associated with mild traumatic brain injury.

Youth Concussion Management Practices Among Athletic Trainers: A Vignette-Based Survey

CONTEXT

Recovery protocols for treatment of sports concussion have received widespread adoption across the country. While stages of recovery and treatment are relatively clearly defined, there remains variability in implementation of specific recommendations, particularly regarding activities that constitute rest during stages calling for limitations on activity participation. Specific recommendations being employed by practitioners have not been previously assessed. In an aim to document current concussion management practices in the field, athletic trainers were surveyed regarding how activities that may constitute rest are utilized and defined.

DESIGN

The study was based on a cross-sectional vignette-based survey.

METHODS

The sample used was a geographically representative convenience sample of United States-based high school athletic trainers. E-mails were sent to 2146 potential survey respondents yielding a final sample of 226 athletic trainers. Data were gathered for questions concerning recommendations for follow-up care and rest based on provided vignettes, factors considered when developing recommendations, and differences in recommendations associated with varying symptom presentations. The percentage of practitioners that would utilize each potential recommendation was used to characterize results.

RESULTS

Participants demonstrated consensus on the importance of physical and cognitive rest as well as school accommodations (all greater than 97% endorsement). Greater variability was present for recommendations regarding pain medication for headache, repeating baseline cognitive testing, and engaging in subsymptom threshold activities. Recommendations for attending but not participating in games and practice yielded conflicting information.

CONCLUSIONS

Responses indicated general consensus regarding factors considered when making recommendations. There was also consensus regarding general recommendations for activity limitation following recovery with almost all participants strongly recommending cognitive and physical rest, in accordance with consensus guidelines. However, substantial differences were found for specific activities that should be limited or encouraged following youth concussion. Further research concerning the relationship between community and social interaction and clinical outcomes after concussion is warranted.

Vestibular performance in high-level soccer and ice hockey players: Sport-specific norm values and implications

OBJECTIVES

Quantitative vestibular testing in athletes after sports-related concussion (SRC) has become more popular due to accompanying injuries of the peripheral-vestibular organs that require targeted treatment. Sports-specific normative values are currently not available. Taking into account potential adaptational mechanisms, we obtained sports-specific, age- and peak-head-velocity-corrected normative values of peripheral-vestibular function and postural-stability in football (soccer, FB) and ice-hockey (IH) players.

DESIGN

Retrospective single-center case-control study.

METHOD

Pre-seasonal angular vestibulo-ocular reflex (aVOR) gains and cumulative-saccadic-amplitudes were obtained using the video-head-impulse test and performance in the balance-error-scoring-system (BESS) was recorded and compared in high-level FB-players (n = 510, 197 females) and IH-players (n = 210, males only) (age-range = 13-39y) and in healthy normals (n = 49, 22 females). Statistical analysis was performed using a generalized linear model.

RESULTS

aVOR-gain values were significantly higher for FB-players than for IH-players (1.07 ± 0.21 vs. 0.98 ± 0.13, p < 0.001) and controls (1.07 ± 0.21 vs. 0.97 ± 0.17, p < 0.001). Significant age-related changes in aVOR-gains were only observed for the anterior and posterior canals in the IH-players. Cumulative-saccadic-amplitudes were clearly below established cut-off values (0.73°/trial). BESS scores were significantly higher in IH-players than in FB-players (15.4 ± 5.1 vs. 11.2 ± 4.9, p < 0.001).

CONCLUSIONS

The significantly better performance of the FB players in the vertical aVOR-gains and the BESS compared to the IH-players could be related to sports-specific differences influencing visuo-vestibular and balance performance. Therefore, we recommend using the established normative aVOR-gain values for high-level FB-players, whereas in IH obtaining individual pre-seasonal (baseline) aVOR-gain values is proposed. Further studies should add sports-specific normative aVOR-gain values for IH and other sports.

Neurobehavior and Mild Traumatic Brain Injury

Neurobehavioral sequelae after mild traumatic brain injury are multifactorial, often necessitating a multidisciplinary approach. Neurobehavioral sequelae generally resolve within 3 months; when more persistent, a search for contributing factors beyond a brain injury should be done. To accomplish this, a systematic and comprehensive evaluation is recommended to place the complaint in context of the patient's premorbid state. The treatment of neurobehavioral sequelae cannot be accomplished without a clear understanding of the underlying cause, and the treatment must be placed within a patient's social and functional framework. Normalizing the experience through education of patients and their families facilitates recovery.

Review of wearable technologies and machine learning methodologies for systematic detection of mild traumatic brain injuries

Mild traumatic brain injuries (mTBIs) are the most common type of brain injury. Timely diagnosis of mTBI is crucial in making 'go/no-go' decision in order to prevent repeated injury, avoid strenuous activities which may prolong recovery, and assure capabilities of high-level performance of the subject. If undiagnosed, mTBI may lead to various short- and long-term abnormalities, which include, but are not limited to impaired cognitive function, fatigue, depression, irritability, and headaches. Existing screening and diagnostic tools to detect acute andearly-stagemTBIs have insufficient sensitivity and specificity. This results in uncertainty in clinical decision-making regarding diagnosis and returning to activity or requiring further medical treatment. Therefore, it is important to identify relevant physiological biomarkers that can be integrated into a mutually complementary set and provide a combination of data modalities for improved on-site diagnostic sensitivity of mTBI. In recent years, the processing power, signal fidelity, and the number of recording channels and modalities of wearable healthcare devices have improved tremendously and generated an enormous amount of data. During the same period, there have been incredible advances in machine learning tools and data processing methodologies. These achievements are enabling clinicians and engineers to develop and implement multiparametric high-precision diagnostic tools for mTBI. In this review, we first assess clinical challenges in the diagnosis of acute mTBI, and then consider recording modalities and hardware implementation of various sensing technologies used to assess physiological biomarkers that may be related to mTBI. Finally, we discuss the state of the art in machine learning-based detection of mTBI and consider how a more diverse list of quantitative physiological biomarker features may improve current data-driven approaches in providing mTBI patients timely diagnosis and treatment.

Severity of Ongoing Post-Concussive Symptoms as a Predictor of Cognitive Performance Following a Pediatric Mild Traumatic Brain Injury

OBJECTIVE

This study aimed to examine the predictors of cognitive performance in patients with pediatric mild traumatic brain injury (pmTBI) and to determine whether group differences in cognitive performance on a computerized test battery could be observed between pmTBI patients and healthy controls (HC) in the sub-acute (SA) and the early chronic (EC) phases of injury.

METHOD

203 pmTBI patients recruited from emergency settings and 159 age- and sex-matched HC aged 8-18 rated their ongoing post-concussive symptoms (PCS) on the Post-Concussion Symptom Inventory and completed the Cogstate brief battery in the SA (1-11 days) phase of injury. A subset (156 pmTBI patients; 144 HC) completed testing in the EC (~4 months) phase.

RESULTS

Within the SA phase, a group difference was only observed for the visual learning task (One-Card Learning), with pmTBI patients being less accurate relative to HC. Follow-up analyses indicated higher ongoing PCS and higher 5P clinical risk scores were significant predictors of lower One-Card Learning accuracy within SA phase, while premorbid variables (estimates of intellectual functioning, parental education, and presence of learning disabilities or attention-deficit/hyperactivity disorder) were not.

CONCLUSIONS

The absence of group differences at EC phase is supportive of cognitive recovery by 4 months post-injury. While the severity of ongoing PCS and the 5P score were better overall predictors of cognitive performance on the Cogstate at SA relative to premorbid variables, the full regression model explained only 4.1% of the variance, highlighting the need for future work on predictors of cognitive outcomes.

Mild Traumatic Brain Injury in Children

Mild traumatic brain injury accounts for an estimated 4.8 million cases of pediatric traumatic brain injuries worldwide every year. In the United States, 70% of mild traumatic brain injury cases are due to sports and recreational injuries. Early diagnosis, especially in active children, is critical to preventing recurrent injuries. Management is guided by graded protocols for returning to school and activity. Ninety percent of children recover within 1 month of injury. Promising research has shown that early referral to specialty concussion care and multidisciplinary treatment with physical and occupational therapy may shorten recovery time and improve neurologic outcomes.

Evolving Science to Inform Emerging Concussion Practices

Purpose This article describes two concussion models built on the current state of science that help illustrate the complicated interactions among the multiple factors that drive concussion symptoms. Consideration of these models remind practitioners, including speech-language pathologists, to attend to factors that increase the risk of patients developing prolonged symptoms, as well as attend to symptoms that result from various interactions and may differentially respond to specific treatments. In particular, the models encourage personalized or precision medicine and the implementation of targeted, coordinated therapies.