Consensus statement on concussion in sport: the 3rd International Conference on Concussion in Sport held in Zurich, November 2008

Concussion in University Level Sport: Knowledge and Awareness of Athletes and Coaches

Using a cross-sectional survey concussion knowledge was evaluated among forty university-level athletes (n = 20, rugby union players; n = 20, Gaelic football players) and eight experienced team coaches (n = 2, rugby union; n = 2, Gaelic football; n = 1, soccer; n = 1, hockey; n = 1, netball; n = 1, basketball). Levels of knowledge of concussion were high across all participants. Coaches had higher knowledge scores for almost all areas; however, there was evidence of important gaps even in this group. Knowledge was not sufficient in identifying concussion, and when it is safe to return to play following a concussion. Impaired knowledge of how to recognise a concussion, and misunderstanding the need for rest and rehabilitation before return to play presents a hazard to health from second impact and more catastrophic brain injury. We discuss reasons for these guideline misconceptions, and suggest that attitude issues on the significance of concussion may underlie a willingness to want to play with a concussion. This suggests the current education on sport-related concussion needs to be expanded for the appropriate management of university-level contact sports.

The First Decade of Web-Based Sports Injury Surveillance (2004-2005 Through 2013-2014): Methods of the National Collegiate Athletic Association Injury Surveillance Program and High School Reporting Information Online

OBJECTIVE: 

To describe the methods of the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) and High School Reporting Information Online (HS RIO) system as a complement to the sport-specific manuscripts that will follow.

BACKGROUND: 

The NCAA-ISP and HS RIO collect injury and exposure data from samples of collegiate and high school sports programs, respectively. The NCAA-ISP, which the NCAA has maintained since 1982, was relaunched as a Web-based platform at the beginning of the 2004-2005 academic year. In 2005, the HS RIO was introduced to capture data on high school athletes and modeled after the NCAA-ISP. Relevant data are shared with the NCAA and high school sport and policy committees to develop evidence-based rules and programs that help protect the health and safety of student-athletes.

DESCRIPTION: 

The NCAA-ISP and HS RIO monitor participation in school-sanctioned competitions and practices that occur from the first preseason practice to the final postseason contest for more than 25 sports. For this series of publications in the Journal of Athletic Training, injury information on 13 sports at the collegiate level during the 2004-2005 through 2013-2014 academic years and the high school level during the 2005-2006 through 2013-2014 academic years was evaluated.

CONCLUSIONS: 

Athletic trainers have been a vital source of data collection over the past decade to help produce the largest datasets of collegiate and high school sports injuries. Such data have helped various sport and policy committees advance protocols that aim to increase sports safety. This series of publications will aid by continuing to provide data to stakeholders in the sports community.

Stability of MRI metrics in the advanced research core of the NCAA-DoD concussion assessment, research and education (CARE) consortium

The NCAA-DoD Concussion Assessment, Research, and Education (CARE) consortium is performing a large-scale, comprehensive study of sport related concussions in college student-athletes and military service academy cadets. The CARE "Advanced Research Core" (ARC), is focused on executing a cutting-edge investigative protocol on a subset of the overall CARE athlete population. Here, we present the details of the CARE ARC MRI acquisition and processing protocol along with preliminary analyzes of within-subject, between-site, and between-subject stability across a variety of MRI biomarkers. Two experimental datasets were utilized for this analysis. First, two "human phantom" subjects were imaged multiple times at each of the four CARE ARC imaging sites, which utilize equipment from two imaging vendors. Additionally, a control cohort of healthy athletes participating in non-contact sports were enrolled in the study at each CARE ARC site and imaged at four time points. Multiple morphological image contrasts were acquired in each MRI exam; along with quantitative diffusion, functional, perfusion, and relaxometry imaging metrics. As expected, the imaging markers were found to have varying levels of stability throughout the brain. Importantly, between-subject variance was generally found to be greater than within-subject and between-site variance. These results lend support to the expectation that cross-site and cross-vendor advanced quantitative MRI metrics can be utilized to improve analytic power in assessing sensitive neurological variations; such as those effects hypothesized to occur in sports-related-concussion. This stability analysis provides a crucial foundation for further work utilizing this expansive dataset, which will ultimately be freely available through the Federal Interagency Traumatic Brain Injury Research Informatics System.

Quantitative Susceptibility Mapping after Sports-Related Concussion

BACKGROUND AND PURPOSE

Quantitative susceptibility mapping using MR imaging can assess changes in brain tissue structure and composition. This report presents preliminary results demonstrating changes in tissue magnetic susceptibility after sports-related concussion.

MATERIALS AND METHODS

Longitudinal quantitative susceptibility mapping metrics were produced from imaging data acquired from cohorts of concussed and control football athletes. One hundred thirty-six quantitative susceptibility mapping datasets were analyzed across 3 separate visits (24 hours after injury, 8 days postinjury, and 6 months postinjury). Longitudinal quantitative susceptibility mapping group analyses were performed on stability-thresholded brain tissue compartments and selected subregions. Clinical concussion metrics were also measured longitudinally in both cohorts and compared with the measured quantitative susceptibility mapping.

RESULTS

Statistically significant increases in white matter susceptibility were identified in the concussed athlete group during the acute (24 hour) and subacute (day 8) period. These effects were most prominent at the 8-day visit but recovered and showed no significant difference from controls at the 6-month visit. The subcortical gray matter showed no statistically significant group differences. Observed susceptibility changes after concussion appeared to outlast self-reported clinical recovery metrics at a group level. At an individual subject level, susceptibility increases within the white matter showed statistically significant correlations with return-to-play durations.

CONCLUSIONS

The results of this preliminary investigation suggest that sports-related concussion can induce physiologic changes to brain tissue that can be detected using MR imaging-based magnetic susceptibility estimates. In group analyses, the observed tissue changes appear to persist beyond those detected on clinical outcome assessments and were associated with return-to-play duration after sports-related concussion.

The Effects of Sex Differences and Hormonal Contraception on Outcomes after Collegiate Sports-Related Concussion

There is conflicting evidence regarding whether females are more adversely affected after concussion than males. Further, recent research suggests that hormonal contraceptive (HC) use may affect symptom severity and duration post-concussion. The objective of this study was to examine the effects of sex and HC use on outcomes following concussion among collegiate varsity athletes. We hypothesized that females would have longer length of recovery (LOR), and that peak symptom severity would be associated with longer LOR in both males and females. Among females, we hypothesized that non-HC users would have longer LOR and higher peak symptom severity than HC users. Ninety collegiate student-athletes were included in this study (40 males, 50 females; 24 HC users, 25 non-HC users). Demographic, injury, and recovery information was abstracted via retrospective record review. LOR was defined as days between injury and clearance for full return to play by team physician. Peak symptom severity score (Sport Concussion Assessment Tool [SCAT] 2 or 3) was used in analyses. Study results revealed that males had shorter LOR than females (F[1, 86] = 5.021, p < 0.05, d = 0.49), but had comparable symptom severity scores. Symptom severity was strongly related to LOR for males (r = 0.513, p < 0.01) but not females (r = -0.003, p > 0.05). Among females, non-HC users demonstrated higher symptom severity than HC users (F[1,47] = 5.142, p < 0.05, d = 0.70). No significant differences between female HC users and non-HC users on LOR were observed. This study provides evidence for differential concussion outcomes between male and female collegiate athletes and between HC users and nonusers among females.

Intracranial pressure changes after mild traumatic brain injury: a systematic review

OBJECTIVE

Intracranial pressure (ICP) after mild traumatic brain injury (mTBI) is poorly studied due to lack of sensitive non-invasive methods. The purpose of this review was to summarize the existing knowledge of changes in ICP after mTBI. Literature selection: PubMed, Embase, CINAHL, and Scopus were searched by three reviewers independently up to December 2016.

INCLUSION CRITERIA

animal and human studies measuring ICP and brain oedema after an mTBI.

EXCLUSION CRITERIA

moderate and severe forms of traumatic brain injury, repeat samples, and studies that measured ICP at the time of impact but not after. Study quality was assessed using Downs and Black criteria.

RESULTS

Of 1067 papers, 9 studies were included. In human studies, one provided direct evidence on increased, one provided indirect evidence of increased, and two provided indirect evidence of decreased ICP. In animal studies, three studies provided direct evidence of increased, one provided indirect evidence of increased, and one provided indirect evidence of no change in ICP.

CONCLUSION

The existing research suggests that there may be increased ICP after mTBI and animal studies suggest an elevation for days which returns to baseline, which corresponds with functional and symptomatic recovery. Future human studies using sensitive indirect methods to measure ICP longitudinally after mTBI are needed.

Plasma metabolomic biomarkers accurately classify acute mild traumatic brain injury from controls

Past and recent attempts at devising objective biomarkers for traumatic brain injury (TBI) in both blood and cerebrospinal fluid have focused on abundance measures of time-dependent proteins. Similar independent determinants would be most welcome in diagnosing the most common form of TBI, mild TBI (mTBI), which remains difficult to define and confirm based solely on clinical criteria. There are currently no consensus diagnostic measures that objectively define individuals as having sustained an acute mTBI. Plasma metabolomic analyses have recently evolved to offer an alternative to proteomic analyses, offering an orthogonal diagnostic measure to what is currently available. The purpose of this study was to determine whether a developed set of metabolomic biomarkers is able to objectively classify college athletes sustaining mTBI from non-injured teammates, within 6 hours of trauma and whether such a biomarker panel could be effectively applied to an independent cohort of TBI and control subjects.

A 6-metabolite panel was developed from biomarkers that had their identities confirmed using tandem mass spectrometry (MS/MS) in our Athlete cohort. These biomarkers were defined at ≤6 hours following mTBI and objectively classified mTBI athletes from teammate controls, and provided similar classification of these groups at the 2, 3, and 7 days post-mTBI. The same 6-metabolite panel, when applied to a separate, independent cohort provided statistically similar results despite major differences between the two cohorts. Our confirmed plasma biomarker panel objectively classifies acute mTBI cases from controls within 6 hours of injury in our two independent cohorts. While encouraged by our initial results, we expect future studies to expand on these initial observations.

Acute Cognitive and Physical Rest May Not Improve Concussion Recovery Time

OBJECTIVE

To evaluate the effectiveness of an acute period of cognitive and physical rest on concussion.

PARTICIPANTS

Fifty consecutive patients with a diagnosis of concussions.

DESIGN

Participants were evaluated before (n = 25) and after (n = 25) a policy change that incorporated cognitive and physical rest. Patients in the rest group were withheld from activities, including classes, for the remainder of the injury day and the following day, whereas patients in the no-rest group were not provided any postinjury accommodations.

MAIN MEASURES

Patients were evaluated on a graded symptom checklist, Balance Error Scoring System, Standard Assessment of Concussion, and computerized neuropsychological tests. The number of days until each test achieved baseline values was compared between groups with independent-samples t test.

RESULTS

The no-rest group achieved asymptomatic status sooner than the rest group (5.2 ± 2.9 days and 3.9 ± 1.9 days, respectively; P = .047). There were no differences between groups for time to baseline values on the Balance Error Scoring System, Standard Assessment of Concussion, computerized neuropsychological tests, or time to clinical recovery.

CONCLUSION

A prescribed day of cognitive and physical rest was not effective in reducing postconcussion recovery time. These results agree with a previous study and suggest that light activity postconcussion may not be deleterious to the concussion recovery process.

Using concurrent gait and cognitive assessments to identify impairments after concussion: a narrative review

Understanding how a concussion affects an individual is oftentimes difficult for clinicians due to the varying symptom profiles reported by the patient and the multifaceted and heterogeneous nature of the injury. Accordingly, the interpretation of postconcussion performance can be challenging, because many different testing paradigms have been reported as potentially useful in the literature. Among the types of tests clinicians use to understand how concussion affects an individual, both gait and neurocognitive evaluations have demonstrated utility. Our purpose is to describe how combined gait and cognitive (i.e., dual task), as well as single-task gait and computerized neurocognitive examinations can assist clinical decision-making.

Structural imaging of mild traumatic brain injury may not be enough: overview of functional and metabolic imaging of mild traumatic brain injury

A majority of patients with traumatic brain injury (TBI) present as mild injury with no findings on conventional clinical imaging methods. Due to this difficulty of imaging assessment on mild TBI patients, there has been much emphasis on the development of diffusion imaging modalities such as diffusion tensor imaging (DTI). However, basic science research in TBI shows that many of the functional and metabolic abnormalities in TBI may be present even in the absence of structural damage. Moreover, structural damage may be present at a microscopic and molecular level that is not detectable by structural imaging modality. The use of functional and metabolic imaging modalities can provide information on pathological changes in mild TBI patients that may not be detected by structural imaging. Although there are various differences in protocols of positron emission tomography (PET), single photon emission computed tomography (SPECT), functional magnetic resonance imaging (fMRI), electroencephalography (EEG), and magnetoencephalography (MEG) methods, these may be important modalities to be used in conjunction with structural imaging in the future in order to detect and understand the pathophysiology of mild TBI. In this review, studies of mild TBI patients using these modalities that detect functional and metabolic state of the brain are discussed. Each modality's advantages and disadvantages are compared, and potential future applications of using combined modalities are explored.

What do coaches want to know about sports-related concussion? A needs assessment study

PURPOSE

This study aims to identify the concussion-related training and education needs of Gaelic Athletic Association (GAA) coaches in Ireland, as well as the preferred method of concussion education delivery.

METHODS

We used a self-report questionnaire to collect data from a convenience sample of 108 GAA coaches in Ireland. Data were captured on (1) informational needs and desires, (2) preferred methods of delivery, and (3) concussion practices and procedures. Questionnaires were completed electronically from June 3rd-September 29th, 2015.

RESULTS

Coaches indicated that they were most interested in receiving information about the (1) signs and symptoms of concussion, (2) assessment of concussion, and (3) return-to-play guidelines. Over two-thirds of participants indicated that in-person training would be the most effective mode of delivery of concussion education for this population. Additionally, only 10% coaches reported that before the start of the season they talked to their athletes about concussion management and safety, and this was more common among coaches who reported being formally educated about concussion.

CONCLUSION

Our findings reveal a disconnect between the concussion education needs and the education that is currently provided to GAA coaches, in terms of content and delivery modality. Our results suggest a need for a multifaceted approach to concussion education, tailored to the needs and learning preferences of the target population.

Comparison of Neurocognitive Performance in Contact and Noncontact Nonconcussed High School Athletes Across a Two-Year Interval

Investigating short-term effects of subconcussive impacts on neurocognitive functioning, we employed a repeated measures multivariate model and regression-based measure to examine neurocognitive changes in 771 contact and noncontact high school athletes over a two-year period. Results reveal significant changes in Visual Motor Speed for both groups over a two-year period, with small effect sizes. According to regression-based measures, differences in contact sport athletes' expected Time 2 performances were significant for Visual Motor Speed, also with minimal effects. Results do not conclusively implicate subconcussive hits as the offending factor in differences observed, with gender and sport-type possibly contributing to the small effects.

GAIT DEFICITS UNDER DUAL - TASK CONDITIONS IN THE CONCUSSED ADOLESCENT AND YOUNG ATHLETE POPULATION: A SYSTEMATIC REVIEW

BACKGROUND

There are no current sport concussion assessments that capture the effects of dual-task conditions on gait. Multiple studies have evaluated changes, but none have comprehensively examined literature related to the adolescent and young adult population.Purpose: The purpose of this systematic review is to synthesize documented changes in gait under dual-task conditions in adolescents and young adults after sustaining a concussion.Study Design: Systematic Review.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was consulted to guide this systematic review. Six databases were searched: Cinahl, ProQuest, PubMed, Scopus, SPORTdiscus, and Web of Science. Concussion, gait, and dual-task, along with their synonymous terms were the search terms used. Inclusion criteria consisted of adolescent and young adult age groups, acute concussion, dual-tasking, and matched controls. Quality assessment was performed using The Joanna Briggs Institute Critical Appraisal Checklist for Case Control Studies.

RESULTS

Ten full-text articles were selected for inclusion. Concussed individuals demonstrated longer stride times with shorter stride lengths, increased mediolateral displacement with corresponding increases in sagittal and frontal plane peak velocity, and decreased sagittal plane Center of Mass (COM) and Center of Pressure (COP) displacement. The majority of included studies demonstrated moderate to large effect sizes in these gait characteristics.

CONCLUSION

Concussed individuals demonstrated decreased gait stability while ambulating with a dual-task condition. Though statistically significant differences between concussed individuals and matched controls lasted only 72 hours, concussed individuals demonstrated continued improvements in gait for up to two months post-injury, which has the potential to affect an athlete's ability to perform. Further research is needed to determine if a gait examination with a dual-task condition is a realistic, reliable, and valid measure to be included in return to sport testing.

LEVEL OF EVIDENCE

2a.

Self-reported history of seizure and baseline neurocognitive test performance in student-athletes: an initial investigation

OBJECTIVES

Baseline neurocognitive assessment data can be critical in return to play (RTP) decision-making following a sport-related concussion (SRC). The literature indicates that many modifying factors of SRC have been studied empirically; however, there has been little investigation into the effect of a self-reported history of seizure(s) on baseline neurocognitive test data. The objective of this investigation was to determine whether a self-reported history of seizure(s) is associated with differences in baseline Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) performance.

METHODS

A retrospective analysis of 18,245 adolescent and young adult athletes' ImPACT scores was performed. After application of inclusion and exclusion criteria, 7,391 participants were dichotomized into groups based on the presence or absence of a self-reported history of seizure. Participants reporting a history of seizure (n = 60) were matched on multiple variables in a 1:3 ratio with controls (n = 180) without a history of self-reported seizure. Baseline ImPACT composite scores were then compared between groups using either a 2-tailed t-test or a Mann-Whitney U-Test.

RESULTS

A significant between-group difference was observed in ImPACT visual motor speed composite scores (35.28 vs. 37.64, p = 0.029, Hedge's g = 0.327), with the group self-reporting a history of seizure performing at inferior average scores. No significant between-group differences were detected in verbal memory, visual memory, reaction time, impulse control, or total symptom scores.

CONCLUSION

Athletes with a history of self-reported seizure scored significantly lower on ImPACT visual motor speed compared to matched controls. As a solitary finding with a small effect size, the clinical significance of this difference is unclear. Apart from the decrease in visual-motor speed, this preliminary analysis suggests that athletes with a history of seizure might not have significantly different neurocognitive baseline test scores when compared with matched controls. Further empirical investigation is warranted to determine if a history of seizure is a modifying factor for SRC.

Sport-Related Concussions: Symptom Recurrence After Return to Exercise

Background:

Current guidelines dictate a gradual exercise progression after a concussion; however, it is unclear what proportion of athletes experience a recurrence of symptoms once they are symptom free at rest. Estimating the proportion of athletes and predictors of symptom recurrence would help shape return-to-play protocols.

Purpose:

To determine the proportion and associated risk factors of athletes who have a recurrence of concussion symptoms with exercise after being symptom free at rest.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

Between October 1, 2009 and July 31, 2011, we studied patients from a sport concussion clinic located within a tertiary care regional children’s hospital. Patients were queried at every visit using a standardized questionnaire. Our main outcome variable was recurrence of symptoms with exercise after being symptom free at rest at some point in their recovery. Cofactors included age, sex, loss of consciousness with injury, prior concussion (diagnosed and undiagnosed), Post-Concussion Symptom Scale (PCSS) score, time until clinical presentation, and duration of symptoms.

Results:

Of the 217 patients included, 25 (12%) experienced a return of symptoms. Losing consciousness at the time of injury and a longer duration between injury and clinical presentation were associated with a decreased risk of symptoms recurring with exercise. Conversely, athletes who had sustained previously undiagnosed concussions and had suffered a longer duration of symptoms at rest were at an increased risk of symptom recurrence with exercise.

Conclusion:

Relatively few athletes who are symptom free at rest after a concussion will have a recurrence of symptoms when they resume exercise. The risk of symptoms recurring with exercise may be greater among those athletes who sustained previously undiagnosed concussions and had a longer period of symptoms at rest. The early identification of athletes who may be at risk of symptom recurrence will help mold treatment guidelines and exercise progression protocols.

Neurometabolic indicators of mitochondrial dysfunction in repetitive mild traumatic brain injury

Mild traumatic brain injury (mTBI) is a significant national health concern and there is growing evidence that repetitive mTBI (rmTBI) can cause long-term change in brain structure and function. The mitochondrion has been suggested to be involved in the mechanism of TBI. There are noninvasive methods of determining mitochondrial dysfunction through biomarkers and spectroscopy. Mitochondrial dysfunction has been implicated in a variety of neurological consequences secondary to rmTBI through activation of caspases and calpains. The purpose of this review is to examine the mechanism of mitochondrial dysfunction in rmTBI and its downstream effects on neuronal cell death, axonal injury and blood–brain barrier compromise.

CranioSacral Therapy and Visceral Manipulation: A New Treatment Intervention for Concussion Recovery

Background: Military service members and veterans face health issues related to traumatic brain injury (TBI), especially during combat, use of heavy equipment, and exposures to environmental hazards and explosives. There were 400,000 TBIs reported in deployed U.S. troops in 2012. Athletes are also subject to TBI. Studies have indicated that some manual therapies could be helpful for treating patients who have post-concussive syndrome.

Objective: This case series report describes the effects of CranioSacral Therapy (CST), Visceral Manipulation (VM), and Neural Manipulation (NM) modalities for treating patients who have post-concussion syndrome. The goal of this study was to evaluate these effects on immobility, pain intensity, quality of life, sleep disorders, and cognition in these patients.

Materials and Methods: This single-blinded case series was conducted at the Upledger Institute, in West Palm Beach, FL. The patients were 11 male retired professional football players from the National Football League and the Canadian Football League who had been medically diagnosed with post-concussion syndrome. Each participant received a morning and afternoon 2-hour session of these three specific manual therapies, which were capable of accessing and addressing the structural, vascular, and neurologic tissues of the cranium and brain—as well addressing far-reaching ramifications throughout the body following trauma. The main outcome measures were scores on the: Impact Neurocognitive Test; Dynavision^tm Test; Short Form–36 Quality of Life Survey, Headache Impact Test, Dizziness Handicap Inventory; a numeric pain rating scale; orthopedic range of motion tests (ROM); and vestibular testing. Hours of sleep were also checked. These outcome measures were registered at baseline, after treatment, and after a 3-month follow up.

Results: Statistically significant differences were seen with a decrease in overall pain rating scale scores (P = 0.0448), and cervicogenic pain levels decreased (P = 0.0486). There were statistically significant increases in Dynavision Average Reaction Time (P = 0.0332), Memory Test (P = 0.0156) scores, and cervical ROM scores (P = 0.0377). Hours of sleep averaged 2 hours on the first day of treatment and increased to 4.0 hours at the end of treatment and were continuing to increase, as noted at a 3-month evaluation.

Conclusions: Ten sessions of specific CST/VM/NM therapy resulted in statistically greater improvements in pain intensity, ROM, memory, cognition, and sleep in concussed patients.

Blood-Based Biomarkers for the Identification of Sports-Related Concussion

Sports-related concussions (SRCs) are common among athletes in the United States. Most athletes who sustain an SRC recover within 7 to 10 days; however, many athletes who sustain the injury do not recover as expected and experience prolonged, persistent symptoms. In this document, the authors provide an overview of the empirical evidence related to the use of blood-based brain biomarkers in the athlete population for diagnosis of SRCs, prognosis of recovery and return to play guidelines, and indications of neurodegeneration. The authors also provide a summary of research challenges, gaps in the literature, and future directions for research.

Rapid sideline performance meets outpatient clinic: Results from a multidisciplinary concussion center registry

OBJECTIVE

This study investigated the utility of sideline concussion tests, including components of the Sports Concussion Assessment Tool, 3rd Edition (SCAT3) and the King-Devick (K-D), a vision-based test of rapid number naming, in an outpatient, multidisciplinary concussion center treating patients with both sports-related and non-sports related concussions. The ability of these tests to predict clinical outcomes based on the scores at the initial visit was evaluated.

METHODS

Scores for components of the SCAT3 and the K-D were fit into regression models accounting for age, gender, and sport/non-sport etiology in order to predict clinical outcome measures including total number of visits to the concussion center, whether the patient reached a SCAT3 symptom severity score≤7, and the total types of referrals each patient received over their course. Patient characteristics, differences between those with sport and non-sport etiologies, and correlations between the tests were also analyzed.

RESULTS

Among 426 patients with concussion, SCAT3 total symptom score and symptom severity score at the initial visit predicted each of the clinical outcome variables. K-D score at the initial visit predicted the total number of visits and the total number of referrals. Those with sports-related concussions were younger, had less severely-affected test scores, had fewer visits and types of referrals, and were more likely to have clinical resolution of their concussion and to reach a symptom severity score≤7.

CONCLUSIONS

This large-scale study of concussion patients supports the use of sideline concussion tests as part of outpatient concussion assessment, especially the total symptom and symptom severity score portions of the SCAT3 and the K-D. Women in this cohort had higher total symptom and symptom severity scores compared to men. Our data also suggest that those with non-sports-related concussions have longer lasting symptoms than those with sports-related concussions, and that these two groups should perhaps be regarded separately when assessing outcomes and needs in a multidisciplinary setting.

Utility of Serum Biomarkers in the Diagnosis and Stratification of Mild Traumatic Brain Injury

OBJECTIVE

The objective was to compare test characteristics of a single serum concentration of glial fibrillary acidic protein (GFAP), S-100β, and ubiquitin carboxyl terminal hydrolase L1 (UCH-L1), obtained within 6 hours of head injury, to diagnose mild traumatic brain injury (mTBI) in head-injured subjects.

METHODS

Adults aged 18 to 80 years who presented to one of seven EDs with a blunt closed head injury underwent head CT within 4 hours of injury and had blood drawn for biomarker analysis within 6 hours of injury were eligible. Subjects were considered to have mTBI if they had an initial Glasgow Coma Scale (GCS) > 13 and met one or more of the following criteria: loss of consciousness (LOC), posttraumatic amnesia, or confusion. Subjects with mTBI and an abnormal head computed tomography (CT) scan were categorized as complicated mTBI; those with a normal head CT were categorized as uncomplicated mTBI; and subjects with a GCS = 15, no LOC, no posttraumatic amnesia, and no confusion were considered to not have a mTBI. Biomarker concentration measurements for GFAP and UCH-L1 were performed using an enzyme-linked immunosorbent assay. S-100β concentration was determined using an electrochemiluminescence immunoassay. Median biomarker concentration for each group was compared using the Kruskal-Wallis test. Logistic regression was used to determine area under the receiver operating curve (AUC) for each of the three biomarkers. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and negative and positive likelihood ratios (LRs) for the three biomarkers to differentiate between complicated mTBI, uncomplicated mTBI, and no mTBI were calculated.

RESULTS

A total of 247 subjects were enrolled and had adequate clinical and biomarker information for analysis. A total of 188 met criteria for mTBI, with 34 (18.1%) having an acute abnormality on CT (complicated mTBI). The mean (±SD) age of the study population was 45.8 (±17.3) years, and 59.9% were male. Median serum concentrations for all biomarkers were significantly different between groups, lowest in the no mTBI group, and progressively increasing in the uncomplicated and complicated mTBI groups (p < 0.0001). All three biomarkers were significant classifiers of mTBI versus no mTBI, with the following AUCs: GFAP, 0.70; S-100β, 0.69; and UCH-L1, 0.65 (p = 0.17). Sensitivity for mTBI was highest for S-100β (96.5%). NPVs ranged from 31% for UCH-L1 to 35% for GFAP. PPVs ranged from 75.5% for S-100β to 96.5% for GFAP. Negative LR ranged from 0.59 for GFAP to 0.71 for UCH-L1, with positive LR ranging from 1.0 for both UCH-L1 and S-100β to 8.7 for GFAP.

CONCLUSION

A single serum concentration of GFAP, UCH-L1, or S-100β within 6 hours of head injury may be useful in identifying and stratifying the severity of brain injury in emergency department patients with head trauma, but cannot reliably exclude a diagnosis of concussion. A positive GFAP was associated with the presence of concussion.

Concussion in pediatric surgical patients scheduled for time-sensitive surgical procedures

Background

Each year in the United States approximately three million individuals sustain sport or recreation-related concussion which may occur in the setting of orthopedic trauma requiring surgical intervention under general anesthesia. The effects of surgery and general anesthesia on brain recovery are currently unknown. The objective of this study was to determine the prevalence of recent sport concussion, recognized or not, in a preoperative, pediatric, surgical population.

Methods

The study involved administering a questionnaire to all eligible, consented patients in one of the following settings: Preoperative Clinic, Day Surgery Unit, Trauma Clinic, or inpatient floor. The questionnaire was designed to determine the occurrence and symptoms of a concussion. This study was conducted at an urban 395-bed comprehensive center for pediatric health, between May 2014 and April 2015. Inclusion criteria for study were age 5–21 years, presentation for surgical repair of orthopedic traumatic injury or nasal fracture, and precipitating injurious event occurring within four weeks of surgery.

Results

The prevalence of concussion in the setting of orthopedic trauma, either known or unknown at the time of presentation for surgery was 6%. The interval between surgery and injury was between three and 13 days. Prior education for recognition of concussion was present in 66% of patients.

Conclusions

The impact of surgery with general anesthesia in pediatric patients with a recent concussion is unknown. No changes in post-op disposition were noted in this patient population. However, our findings support the need to measure neurocognitive function before and after administration of operative procedures in a larger population with a recent concussion compared with controls.

Prevalence of head injury and medically diagnosed concussion in junior-level community-based Australian Rules Football

AIM

For junior-level Australian Rules Football there is a paucity of head injury and concussion surveillance data; thus, the primary aim was to document head injury and concussion incidence in participants aged 9-17 years with a secondary aim to identify the mechanism-of-injury.

METHODS

A prospective cohort study in which a designated representative for each of the 41 teams recorded on a weekly basis the number of head injuries suspected of being a concussion, diagnosed concussions and the mechanism-of-injury during competition games over the course of a 12-game season. For analysis three groups were formed - number of Player-Seasons, Athlete-Exposures, head injury and concussion incidence per 1000 Athlete-Exposures - and were calculated. Narrative data was categorised.

RESULTS

There was 13 reported head injuries resulting in seven concussions in the sample population (n = 976). The incidence rates for head injury and concussion were 1.1 (95% confidence interval: 0.5-1.7) and 0.59 (95% confidence interval: 0.2-1.0) per 1000 Athlete-Exposures. There were four head injuries resulting in two concussions in the 12-13-year-old group and nine head injuries and five concussions in the 14-17-year-old group. Two categories emerged for mechanism-of-injury: player-to-surface and player-to-player, with 9 of the 13 head injuries resulting from player-to-player contact.

CONCLUSIONS

The incidence rates were similar in the two older groups and lower in comparison with American football and rugby. The data collected have advanced our knowledge of head injury incidence and established baseline data which to compare in future years and may assist in development of preventative measures.

Acute plasma tau relates to prolonged return to play after concussion

Objective:

To determine whether tau changes after sport-related concussion (SRC) relate to return to play (RTP).

Methods:

Collegiate athletes underwent preseason plasma sampling and cognitive testing and were followed. After a SRC (n = 46), athletes and controls (n = 37) had sampling at 6 hours, and at 24 hours, 72 hours, and 7 days after SRC. A sample of 21 nonathlete controls were compared at baseline. SRC athletes were grouped by long (>10 days, n = 23) and short (≤10 days, n = 18) RTP. Total tau was measured using an ultrasensitive immunoassay.

Results:

Both SRC and athlete controls had significantly higher mean tau at baseline compared to nonathlete healthy controls (F_101,3 = 19.644, p < 0.01). Compared to SRC athletes with short RTP, those with long RTP had higher tau concentrations overall, after controlling for sex (F_39,1 = 3.59, p = 0.022), compared to long RTP athletes, at 6 (p < 0.01), 24 (p < 0.01), and 72 hours (p = 0.02). Receiver operator characteristic analyses showed that higher plasma tau 6 hours post-SRC was a significant predictor of RTP >10 days (area under the curve 0.81; 95% confidence interval 0.62–0.97, p = 0.01).

Conclusions:

Elevated plasma tau concentration within 6 hours following a SRC was related to having a prolonged RTP, suggesting that tau levels may help inform RTP.

Lower Extremity Stiffness Changes after Concussion in Collegiate Football Players

PURPOSE

Recent research indicates that a concussion increases the risk of musculoskeletal injury. Neuromuscular changes after concussion might contribute to the increased risk of injury. Many studies have examined gait postconcussion, but few studies have examined more demanding tasks. This study compared changes in stiffness across the lower extremity, a measure of neuromuscular function, during a jump-landing task in athletes with a concussion (CONC) to uninjured athletes (UNINJ).

METHODS

Division I football players (13 CONC and 26 UNINJ) were tested pre- and postseason. A motion capture system recorded subjects jumping on one limb from a 25.4-cm step onto a force plate. Hip, knee, and ankle joint stiffness were calculated from initial contact to peak joint flexion using the regression line slopes of the joint moment versus the joint angle plots. Leg stiffness was (peak vertical ground reaction force [PVGRF]/lower extremity vertical displacement) from initial contact to peak vertical ground reaction force. All stiffness values were normalized to body weight. Values from both limbs were averaged. General linear models compared group (CONC, UNINJ) differences in the changes of pre- and postseason stiffness values.

RESULTS

Average time from concussion to postseason testing was 49.9 d. The CONC group showed an increase in hip stiffness (P = 0.03), a decrease in knee (P = 0.03) and leg stiffness (P = 0.03), but no change in ankle stiffness (P = 0.65) from pre- to postseason.

CONCLUSION

Lower extremity stiffness is altered after concussion, which could contribute to an increased risk of lower extremity injury. These data provide further evidence of altered neuromuscular function after concussion.

Academic Outcomes in High-School Students after a Concussion: A Retrospective Population-Based Analysis

BACKGROUND

Many concussion symptoms, such as headaches, vision problems, or difficulty remembering or concentrating may deleteriously affect school functioning. Our objective was to determine if academic performance was lower in the academic calendar year that students sustain a concussion compared to the previous year when they did not sustain a concussion.

METHODS

Using Manitoba Health and Manitoba Education data, we conducted a population-based, controlled before-after study from 2005-2006 to 2010-2011 academic years. Grade 9-12 students with an ICD9/10 code for concussion were matched to non-concussed controls. Overall changes in grade point average (GPA) were compared for the academic year prior to the concussion to the academic year the concussion occurred (or could have occurred among non-concussed matched students).

RESULTS

Overall, 8240 students (1709 concussed, 6531 non-concussed students) were included. Both concussed and non-concussed students exhibited a lower overall GPA from one year to the next. Having sustained a concussion resulted in a -0.90% (95% CI: -1.88, 0.08) reduction in GPA. Over the same period, non-concussed matched students' GPA reduced by -0.57% (95% CI: -1.32, 0.19). Students who sustained a concussion during high school were just as likely to graduate within four years as their non-concussed peers (ORadj: 0.84; 95% CI: 0.73, 1.02).

CONCLUSIONS

We found that, at a population level, a concussion had minimal long-term effects on academic performance during high school. While academic accommodations and Return-to-Learn programs are an important component of pediatric concussion management, research is needed to identify risk factors for poor academic performance after a concussion and who should receive these programs.

Combat-Acquired Traumatic Brain Injury, Posttraumatic Stress Disorder, and Their Relative Associations With Postdeployment Binge Drinking

OBJECTIVE

To examine whether experiencing a traumatic brain injury (TBI) on a recent combat deployment was associated with postdeployment binge drinking, independent of posttraumatic stress disorder (PTSD).

METHODS

Using the 2008 Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel, an anonymous survey completed by 28 546 personnel, the study sample included 6824 personnel who had a combat deployment in the past year. Path analysis was used to examine whether PTSD accounted for the total association between TBI and binge drinking.

MAIN MEASURES

The dependent variable, binge drinking days, was an ordinal measure capturing the number of times personnel drank 5+ drinks on one occasion (4+ for women) in the past month. Traumatic brain injury level captured the severity of TBI after a combat injury event exposure: TBI-AC (altered consciousness only), TBI-LOC of 20 or less (loss of consciousness up to 20 minutes), and TBI-LOC of more than 20 (loss of consciousness >20 minutes). A PTSD-positive screen relied on the standard diagnostic cutoff of 50+ on the PTSD Checklist-Civilian.

RESULTS

The final path model found that while the direct effect of TBI (0.097) on binge drinking was smaller than that of PTSD (0.156), both were significant. Almost 70% of the total effect of TBI on binge drinking was from the direct effect; only 30% represented the indirect effect through PTSD.

CONCLUSION

Further research is needed to replicate these findings and to understand the underlying mechanisms that explain the relationship between TBI and increased postdeployment drinking.

Depression as a Modifying Factor in Sport-Related Concussion: A Critical Review of the Literature

Since its third iteration in 2008, the international Concussion in Sport Group (CISG) has delineated several 'modifying factors' that have the potential to influence the management of sport-related concussions (SRC). One of these factors is co- and pre-morbidities, which includes migraines, mental health disorders, attention-deficit hyperactive disorder (ADHD), learning disability, and sleep disorders. Mental health disorders, and in particular, depression, have received some attention in the management of SRC and in this review we summarize the empirical evidence for its inclusion as a modifying factor. This review is divided into three main bodies of findings: (1) the incidence and prevalence of depression and depressive symptoms in non-concussed and concussed athletes, with comparison made to the general population; (2) managing the post-concussion athlete and accounting for premorbid depressive symptoms; and (3) depression as a long-term effect of repetitive head trauma. Overall, it has been reported that certain subpopulations of athletes have similar or even higher rates of depressive symptoms when compared to the general population. The challenge of accounting for these baseline-depressive symptoms while managing the post-concussive athlete is stressed. And lastly, the prevalence of depression and its relationship to concussion in later-life is discussed.

Implication of Socio-Demographics on Cognitive-Related Symptoms in Sports Concussion Among Children

Background

Sports-related concussion remains a public health challenge due to its morbidity and mortality. One of the consequences of concussion is cognitive impairment (CI) and cognitive-related symptoms (CRS) which determine, to some extent, physical and behavioral functioning of children who sustain concussion. Despite the high prevalence of CI and CRS associated with concussion, the risk factors are not fully understood. We aimed to characterize CRS and to examine its relationship with race, ethnicity, age, insurance, and sex in a pediatric population.

Methods

A retrospective cohort (case-only) design was used to assess CRS prevalence and its relationship with race and sex using a pediatric hospital’s electronic medical records. A consecutive sample was used with 1429 cases between 2007 and 2014. Study characteristics were examined using chi-square and log binomial regression for hypothesis-specific testing.

Results

Of the 1429 cases, 872 (61.0 %) were boys and 557 (39.0 %) were girls. The racial distribution indicated 1146 (80.2 %) Whites, 170 (11.9 %) Blacks/African Americans, and 113 (7.9 %) others. The prevalence of CRS was 78.0 %. Whereas boys had sustained more concussions, girls were more likely to present with CRS; prevalence risk ratio = 1.07, 95 % CI 1.01–1.13, p = 0.02. The crude analysis indicated no racial disparities in CRS prevalence, but the multivariable analysis did, comparing White to Black/African American children; adjusted prevalence risk ratio (aPRR) = 1.77, 99 % CI 1.02–3.08, p = 0.008.

Conclusions

Racial disparities exist in CRS among children with sports-related concussion, and Black/African American children are more likely, relative to Whites, to suffer CRS. Due to uncertainty in causal inference, we caution the interpretation and application of these data in risk-adapted concussion prevention.

Long-term Stability and Reliability of Baseline Cognitive Assessments in High School Athletes Using ImPACT at 1-, 2-, and 3-year Test-Retest Intervals

OBJECTIVE

The ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) neurocognitive testing battery is a widely used tool used for the assessment and management of sports-related concussion. Research on the stability of ImPACT in high school athletes at a 1- and 2-year intervals have been inconsistent, requiring further investigation. We documented 1-, 2-, and 3-year test-retest reliability of repeated ImPACT baseline assessments in a sample of high school athletes, using multiple statistical methods for examining stability.

METHODS

A total of 1,510 high school athletes completed baseline cognitive testing using online ImPACT test battery at three time periods of approximately 1- (N = 250), 2- (N = 1146), and 3-year (N = 114) intervals. No participant sustained a concussion between assessments.

RESULTS

Intraclass correlation coefficients (ICCs) ranged in composite scores from 0.36 to 0.90 and showed little change as intervals between assessments increased. Reliable change indices and regression-based measures (RBMs) examining the test-retest stability demonstrated a lack of significant change in composite scores across the various time intervals, with very few cases (0%-6%) falling outside of 95% confidence intervals.

CONCLUSION

The results suggest ImPACT composites scores remain considerably stability across 1-, 2-, and 3-year test-retest intervals in high school athletes, when considering both ICCs and RBM. Annually ascertaining baseline scores continues to be optimal for ensuring accurate and individualized management of injury for concussed athletes. For instances in which more recent baselines are not available (1-2 years), clinicians should seek to utilize more conservative range estimates in determining the presence of clinically meaningful change in cognitive performance.

Diffusion Tensor Imaging of TBI: Potentials and Challenges

Neuroimaging plays a critical role in the setting in traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is an advanced magnetic resonance imaging technique that is capable of providing rich information on the brain's neuroanatomic connectome. The purpose of this article is to systematically review the role of DTI and advanced diffusion techniques in the setting of TBI, including diffusion kurtosis imaging (DKI), neurite orientation dispersion and density imaging, diffusion spectrum imaging, and q-ball imaging. We discuss clinical applications of DTI and review the DTI literature as it pertains to TBI. Despite the continued advancements in DTI and related diffusion techniques over the past 20 years, DTI techniques are sensitive for TBI at the group level only and there is insufficient evidence that DTI plays a role at the individual level. We conclude by discussing future directions in DTI research in TBI including the role of machine learning in the pattern classification of TBI.

Genome-Wide Changes in Peripheral Gene Expression following Sports-Related Concussion

We conducted a prospective study to identify genome-wide changes in peripheral gene expression before and after sports-related concussion (SRC). A total of 253 collegiate contact athletes underwent collection of peripheral blood mononuclear cells (PBMCs) before the sport season (baseline). Sixteen athletes who subsequently developed an SRC, along with 16 non-concussed teammate controls, underwent repeat collection of PBMCs within 6 h of injury (acutely). Concussed athletes underwent additional sample collection at 7 days post-injury (sub-acutely). Messenger RNA (mRNA) expression at baseline was compared with mRNA expression acutely and sub-acutely post-SRC. To estimate the contribution of physical exertion to gene changes, baseline samples from athletes who subsequently developed an SRC were compared with samples from uninjured teammate controls collected at the acute time-point. Clinical outcome was determined by changes in post-concussive symptoms, postural stability, and cognition from baseline to the sub-acute time-point. SRC athletes had significant changes in mRNA expression at both the acute and sub-acute time-points. There were no significant expression changes among controls. Acute transcriptional changes centered on interleukins 6 and 12, toll-like receptor 4, and NF-κB. Sub-acute gene expression changes centered on NF-κB, follicle stimulating hormone, chorionic gonadotropin, and protein kinase catalytic subunit. All SRC athletes were clinically back to baseline by Day 7. In conclusion, acute post-SRC transcriptional changes reflect regulation of the innate immune response and the transition to adaptive immunity. By 7 days, transcriptional activity is centered on regulating the hypothalamic-pituitary-adrenal axis. Future efforts to compare expressional changes in fully recovered athletes with those who do not recover from SRC could suggest putative targets for therapeutic intervention.

Predictors of delayed recovery following pediatric sports-related concussion: a case-control study

OBJECT Pediatric sports-related concussions are a growing public health concern. The factors that determine injury severity and time to recovery following these concussions are poorly understood. Previous studies suggest that initial symptom severity and diagnosis of attention deficit hyperactivity disorder (ADHD) are predictors of prolonged recovery (> 28 days) after pediatric sports-related concussions. Further analysis of baseline patient characteristics may allow for a more accurate prediction of which patients are at risk for delayed recovery after a sports-related concussion. METHODS The authors performed a single-center retrospective case-control study involving patients cared for at the multidisciplinary Concussion Clinic at Children's of Alabama between August 2011 and January 2013. Patient demographic data, medical history, sport concussion assessment tool 2 (SCAT2) and symptom severity scores, injury characteristics, and patient balance assessments were analyzed for each outcome group. The control group consisted of patients whose symptoms resolved within 28 days. The case group included patients whose symptoms persisted for more than 28 days. The presence or absence of the SCAT2 assessment had a modifying effect on the risk for delayed recovery; therefore, stratum-specific analyses were conducted for patients with recorded SCAT2 scores and for patients without SCAT2 scores. Unadjusted ORs and adjusted ORs (aORs) for an association of delayed recovery outcome with specific risk factors were calculated with logistic regression analysis. RESULTS A total of 294 patients met the inclusion criteria of the study. The case and control groups did not statistically significantly differ in age (p = 0.7). For the patients who had received SCAT2 assessments, a previous history of concussion (aOR 3.67, 95% CI 1.51-8.95), presenting SCAT2 score < 80 (aOR 5.58, 95% CI 2.61-11.93), and female sex (aOR 3.48, 95% CI 1.43-8.49) were all associated with a higher risk for postconcussive symptoms lasting more than 28 days. For patients without SCAT2 scores, female sex and reporting a history of ADHD significantly increased the odds of prolonged recovery (aOR 4.41, 95% CI 1.93-10.07 and aOR 3.87, 95% CI 1.13-13.24, respectively). Concussions resulting from playing a nonhelmet sport were also associated with a higher risk for prolonged symptoms in patients with and without SCAT2 scores (OR 2.59, 95% CI 1.28-5.26 and OR 2.17, 95% CI 0.99-7.73, respectively). Amnesia, balance abnormalities, and a history of migraines were not associated with symptoms lasting longer than 28 days. CONCLUSIONS This case-control study suggests candidate risk factors for predicting prolonged recovery following sports-related concussion. Large prospective cohort studies of youth athletes examined and treated with standardized protocols will be needed to definitively establish these associations and confirm which children are at highest risk for delayed recovery.

The Prevalence of Depression and Concussions in a Sample of Active North American Semi-Professional and Professional Football Players

BACKGROUND

Concussive events frequently occur in high impact sports such as North American football. The long term effects of concussive events on physical and psychological wellbeing are the focus of ongoing research. The purpose of this study was to determine if concussive events increase the incidence of depression in active semi-professional and professional North American football players.

METHODS

An anonymous online survey was sent to 200 players to collect the following self-reported data: position played, years played, number of concussions sustained and subsequent depressive symptoms using the Center for Epidemiologic Studies Depression (CESD-R) scale. An independent T-test was used to determine differences in the number of concussive events in those with CESD-R scores <16 vs. ≥16, where scores ≥16 are indicative of a depressed state. Likewise, an independent T-test was used to compare CESD-R scores between players with ≥3 concussions vs. ≤2.

RESULTS

Individuals with a CESD-R score ≥16, sustained a significantly greater number of concussions (3.8 vs. 1.6) than those who scored <16 (p < 0.001). Further analysis also revealed significantly higher CESD-R scores in players who had sustained ≥3 concussions (24.0 vs. 15.6) than those with ≤2 (p < 0.05).

CONCLUSION

Within the parameters of this study, players that were classified as depressed had sustained significantly more concussions compared to those who were not classified as depressed. Further, multiple concussive events (≥3) appears to increase symptoms of depression.

Neurosensory Symptom Complexes after Acute Mild Traumatic Brain Injury

Mild Traumatic Brain Injury (mTBI) is a prominent public health issue. To date, subjective symptom complaints primarily dictate diagnostic and treatment approaches. As such, the description and qualification of these symptoms in the mTBI patient population is of great value. This manuscript describes the symptoms of mTBI patients as compared to controls in a larger study designed to examine the use of vestibular testing to diagnose mTBI. Five symptom clusters were identified: Post-Traumatic Headache/Migraine, Nausea, Emotional/Affective, Fatigue/Malaise, and Dizziness/Mild Cognitive Impairment. Our analysis indicates that individuals with mTBI have headache, dizziness, and cognitive dysfunction far out of proportion to those without mTBI. In addition, sleep disorders and emotional issues were significantly more common amongst mTBI patients than non-injured individuals. A simple set of questions inquiring about dizziness, headache, and cognitive issues may provide diagnostic accuracy. The consideration of other symptoms may be critical for providing prognostic value and treatment for best short-term outcomes or prevention of long-term complications.

Initial symptom burden predicts duration of symptoms after concussion

OBJECTIVES

To determine which variables predict prolonged (>28 days) duration of symptoms after a concussion.

DESIGN

We conducted a prospective cohort study of adult (>18yo) patients cared for in a specialty concussion clinic.

METHODS

Symptoms were assessed using the Post-Concussion Symptom Scale (PCSS) developed at the 3rd International Conference on Concussion in Sports. Possible predictors including age, sex, loss of consciousness, amnesia, history of prior concussion, prior treatment for headaches, history of migraines, and family history of concussions, were measured by self-report. We recorded a PCSS score at each clinical visit and defined time to symptom resolution as the number of days between the date of injury and date of last symptoms.

RESULTS

Of 64 adult patients included in the study, 53.3% were male; 20.3% reported experiencing a loss of consciousness at the time of injury while 23.4% reported amnesia. Patients ranged in age from 18 to 27 years (mean 21±2 years). Most concussions (92.2%) occurred during sports. The mean initial PCSS score for those suffering symptoms for longer than 28 days was significantly higher than those who symptoms resolved within 28 days (42.5 vs. 19.2, p<0.01). Of all potential predictor variables, only the initial PCSS score was independently associated with the odds of symptoms lasting longer than 28 days (aOR 1.037; 95% CI 1.011, 1.063).

CONCLUSIONS

Among adult patients with concussions, those with a higher symptom burden after injury have an increased odds of suffering from prolonged symptoms. Other potential predictor variables are not associated with the risk of prolonged recovery.

University Football Players, Postural Stability, and Concussions

Concussion in football athletes is certainly more prevalent and has potentially serious outcomes. With current concerns and increasing return-to-play issues, additional assessment focus is needed. Division 1 college football athletes, from 18 to 20.9 years (n = 177; age, 19.7 ± 1.2 years; height, 182.3 ± 4.5 cm; weight, 97.3 ± 10.6 kg), before fall practice, over a period of 3 years, underwent baseline postural stability testing (sensory organization test [SOT], NeuroCom). Individuals, who were diagnosed with a concussion (headache, dizziness, fatigue, confusion, or loss of consciousness) during practice or actual competition (n = 15; age, 18.9 ± 0.9 years; height, 181.8 ± 2.5 cm; weight, 86.6 ± 3.6 kg), underwent serial evaluation after injury and 24 hours after concussion. As soon as the player was considered asymptomatic, the test was completed on the first and 14th day. A control group of noninjured male athletes (n = 15; age, 19.1 ± 0.4 years; height, 178.2 ± 3.2 cm; weight, 78.6 ± 2.1 kg) were tested for the same time frame. This particular study was only one part of the total evaluation conducted for the concussed athlete's return to play. Results indicated that the concussion group had a statistically significant (p = 0.037) change from their baseline SOT score and the control group (p = 0.025). This change remained significant until day 14 of posttesting. These data indicate that the SOT, when available, may be a positive additional assessment of concussed college-aged football players. Professionals, when dealing with concussion in competitive sports, do need to continue to work together, but awareness of SOT assessments may also contribute to the return-to-play decisions.

Concussion-Management Practice Patterns of National Collegiate Athletic Association Division II and III Athletic Trainers: How the Other Half Lives

CONTEXT

The National Collegiate Athletic Association (NCAA) has published concussion-management practice guidelines consistent with recent position and consensus statements. Whereas NCAA Division I athletic trainers appear highly compliant, little is known about the concussion-management practice patterns of athletic trainers at smaller institutions where staffing and resources may be limited.

OBJECTIVE

To descriptively define the concussion-management practice patterns of NCAA Division II and III athletic trainers.

DESIGN

Cross-sectional study.

SETTING

Web-based questionnaire.

PATIENTS OR OTHER PARTICIPANTS

A total of 755 respondents (response rate = 40.2%) from NCAA Division II and Division III institutions.

MAIN OUTCOME MEASURE(S)

The primary outcome measures were the rate of multifaceted concussion-assessment techniques, defined as 3 or more assessments; the specific practice patterns of each assessment battery; and tests used during a clinical examination.

RESULTS

Most respondents indicated using a multifaceted assessment during acute assessment (Division II = 76.9%, n = 473; Division III = 76.0%, n = 467) and determination of recovery (Division II = 65.0%, n = 194; Division III = 63.1%, n = 288) but not at baseline (Division II = 43.1%, n = 122; Division III = 41.0%, n = 176). Typically, when a postconcussion assessment was initiated, testing occurred daily until baseline values were achieved, and most respondents (80.6% [244/278]) reported using a graded exercise protocol before return to participation.

CONCLUSIONS

We found limited use of the multifaceted assessment battery at baseline but higher rates at both acute assessment and return-to-participation time points. A primary reason cited for not using test-battery components was a lack of staffing or funding for the assessments. We observed limited use of neuropsychologists to interpret neuropsychological testing. Otherwise, most respondents reported concussion-management protocols consistent with recommendations, including a high level of use of objective measures and incorporation of a progressive return-to-participation protocol.

A Balanced Protocol for Return to School for Children and Youth Following Concussive Injury

BACKGROUND

Few protocols exist for returning children/youth to school after concussion. Childhood concussion can significantly affect school performance, which is vital to social development, academic learning, and preparation for future roles. The goal of this knowledge translation research was to develop evidence based materials to inform physicians about pediatric concussion.

METHODS

The Return to School (RTS) concussion protocol was developed following the National Institute for Health and Care Excellence procedures.

RESULTS

Based on a scoping review, and stakeholder opinions, an RTS protocol was developed for children/youth. This unique protocol focuses on school adaptation in 4 main areas: (a) timetable/attendance, (b) curriculum, (c) environmental modifications, and (d) activity modifications.

CONCLUSION

A balance of cognitive rest and timely return to school need to be considered for returning any student to school after a concussion. Implementation of these new recommendations may be an important tool in prevention of prolonged absence from school and academic failure while supporting brain recovery.

Biomechanics of head impacts associated with diagnosed concussion in female collegiate ice hockey players

Epidemiological evidence suggests that female athletes may be at a greater risk of concussion than their male counterparts. The purpose of this study was to examine the biomechanics of head impacts associated with diagnosed concussions in a cohort of female collegiate ice hockey players. Instrumented helmets were worn by 58 female ice hockey players from 2 NCAA programs over a three year period. Kinematic measures of single impacts associated with diagnosed concussion and head impact exposure on days with and without diagnosed concussion were evaluated. Nine concussions were diagnosed. Head impact exposure was greater in frequency and magnitude on days of diagnosed concussions than on days without diagnosed concussion for individual athletes. Peak linear accelerations of head impacts associated with diagnosed concussion in this study are substantially lower than those previously reported in male athletes, while peak rotational accelerations are comparable. Further research is warranted to determine the extent to which female athletes' biomechanical tolerance to concussion injuries differs from males.

The King-Devick test for sideline concussion screening in collegiate football

PURPOSE

Sports-related concussion has received increasing attention as a result of neurologic sequelae seen among athletes, highlighting the need for a validated, rapid screening tool. The King-Devick (K-D) test requires vision, eye movements, language function and attention in order to perform and has been proposed as a promising tool for assessment of concussion. We investigated the K-D test as a sideline screening tool in a collegiate cohort to determine the effect of concussion.

METHODS

Athletes (n=127, mean age 19.6±1.2 years) from the Wheaton College football and men's and women's basketball teams underwent baseline K-D testing at pre-season physicals for the 2012-2013 season. K-D testing was administered immediately on the sidelines for football players with suspected head injury during regular games and changes compared to baseline were determined. Post-season testing was also performed to compare non-concussed athletes' test performance.

RESULTS

Concussed athletes (n=11) displayed sideline K-D scores that were significantly higher (worse) than baseline (36.5±5.6s vs. 31.3±4.5s, p<0.005, Wilcoxon signed-rank test). Post-season testing demonstrated improvement of scores and was consistent with known learning effects (35.1±5.2s vs. 34.4±5.0s, p<0.05, Wilcoxon signed-rank test). Test-retest reliability was analyzed between baseline and post-season administrations of the K-D test resulting in high levels of test-retest reliability (intraclass correlation coefficient (ICC)=0.95 [95% Confidence Interval 0.85-1.05]).

CONCLUSIONS

The data show worsening of K-D test scores following concussion further supporting utility of the K-D test as an objective, reliable and effective sideline visual screening tool to help identify athletes with concussion.

Sleep disturbance and neurocognitive function during the recovery from a sport-related concussion in adolescents

BACKGROUND

Sleep disturbances are a hallmark sign after a sport-related concussion (SRC). Poor sleep has been shown to adversely affect baseline neurocognitive test scores, but it is not comprehensively understood how neurocognitive function is affected by disrupted sleep during recovery from a concussion.

PURPOSE

To identify the correlation between adolescent athletes' neurocognitive function and their self-reported sleep quantity and sleep disturbance symptoms during recovery from SRC.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Immediate Post-Concussion Assessment and Cognition Testing (ImPACT) data were retrospectively collected for 545 adolescent athletes treated for SRC at a sports medicine concussion clinic. Patients were stratified into groups based on 2 criteria: self-reported sleep duration and self-reported sleep disturbance symptoms during postinjury ImPACT testing. Sleep duration was classified as short (<7 hours), intermediate (7-9 hours), and long (>9 hours). Sleep disturbance symptoms were self-reported as part of the Post-Concussion Symptom Scale (PCSS) as either sleeping less than normal, sleeping more than normal, or having trouble falling asleep. One-way analyses of variance were conducted to examine the effects that sleep duration as well as self-reported sleep disturbance symptoms had on composite scores. A total of 1067 ImPACT tests were analyzed: test 1, 545; test 2, 380; and test 3, 142.

RESULTS

Sleeping fewer than 7 hours the night before testing correlated with higher PCSS scores (P < .001), whereas sleeping longer than 9 hours correlated with worse visual memory (P = .01), visual motor speed (P <.001), and reaction time (P = .04) composite scores. With regard to self-reported sleep disturbance symptoms, patients demonstrated worse composite scores during ImPACT testing when they self-reported sleeping more than normal (ImPACT test 1: verbal memory, P < .001; visual motor speed, P = .05; reaction time, P = .01; ImPACT test 2: verbal memory, P < .001; visual memory, P < .001; visual motor speed, P < .001; reaction time, P = .01). Adolescent patients recovering from SRC demonstrated higher (worse) PCSS scores (P < .001) when they sensed that their sleep had been disrupted.

CONCLUSION

Adolescent patients who perceive that their sleep is somehow disrupted after SRC may report a greater number of concussion symptoms during their recovery. In addition, the study results suggest that sleeping more than normal may identify an individual who continues to be actively recovering from concussion, given the correlation between lower neurocognitive function and this self-reported symptom.

Agreement between athlete-recalled and clinically documented concussion histories in former collegiate athletes

BACKGROUND

Athlete-recalled and clinically documented concussion histories have been used in research on former athletes, but both have limitations. Comparisons of these 2 types of concussion histories are needed to improve the accuracy of estimates of concussion history for future research and clinical care.

PURPOSE

To estimate the agreement between athlete-recalled and clinically documented concussion histories during college and to explore reasons for differences.

STUDY

Cohort study (diagnosis); Level of evidence, 3.

METHODS

Athlete-recalled concussion histories were provided by a convenience sample of 130 former collegiate athletes using an online questionnaire, and they were individually linked to previously collected clinical data that tracked medically diagnosed concussions at the host institution from 1996 to 2012. The intraclass correlation coefficient (ICC2,1) was used to assess agreement between athlete-recalled and clinically documented concussion histories. Descriptive analyses were performed to assess reasons for disagreement.

RESULTS

Agreement between athlete-recalled and clinically documented concussion histories was low (ICC2,1 = 0.21; 95% confidence interval, 0.05-0.37), but it was higher for women (ICC2,1 = 0.65; 95% confidence interval, 0.44-0.79) and for athletes playing more recently (2005-2012; ICC2,1 = 0.39; 95% confidence interval, 0.01-0.67). Of the 53 athletes who self-reported college sports-related concussions, 40% believed that they sustained impacts that should have been diagnosed as concussions but were undetected, and 21% admitted nondisclosure of suspected concussions. Common reasons for nondisclosure included the following: did not think injury was serious enough (91%), did not know it was a concussion (73%), and did not want to leave the game/practice (73%).

CONCLUSION

Given the low agreement between athlete-recalled and clinically documented concussion histories, methodologic research is needed to improve the quality of tools used to assess concussion histories in former athletes.