Consensus statement on concussion in sport--the 4th International Conference on Concussion in Sport held in Zurich, November 2012

Association between concussion education and concussion knowledge, beliefs and behaviours among youth ice hockey parents and coaches: a cross-sectional study

OBJECTIVES

To examine the association between self-reported exposure to concussion education and knowledge, beliefs and self-reported behaviour among parents and coaches of youth ice hockey players.

DESIGN

Cross-sectional.

SETTING

Community ice hockey teams from Calgary and Edmonton, Alberta, Canada.

PARTICIPANTS

Parents and coaches of ice hockey players (ages 11-17, all divisions of play).

PRIMARY AND SECONDARY OUTCOME MEASURES

Participants completed a questionnaire developed and validated to measure concussion knowledge, beliefs and concussion management behaviour (ie, coaches removing athletes from play; parents taking children with suspected concussions to physicians) consistent with the Health Action Process Approach (HAPA). The questionnaire examined specific HAPA constructs (ie, risk perception, outcome expectancies, action self-efficacy, intention, action planning, maintenance self-efficacy, recovery self-efficacy) relevant to concussion management behaviour.

RESULTS

Participants included 786 parents (31.8% with coaching experience) and 10 non-parent coaches. Of the participants, 649 (82.6%) previously received concussion education. Based on a multivariable regression analysis adjusting for coaching experience, previous history of a child sustaining one or more concussions, first aid experience and cluster by team, exposure to concussion education was associated with a mean score difference of 1.36 (95% CI 0.68 to 2.03), p<0.0001, in the knowledge score. Exposure to concussion education was not significantly associated with any of the HAPA constructs based on Wilcoxon rank-sum tests.

CONCLUSION

Exposure to concussion education may be associated with small overall differences in concussion knowledge but may not be associated with significant differences in beliefs or intended behaviours related to concussion management among youth hockey parents and coaches.When providing education or recommendations for concussion education sources to coaches and parents, educational strategies grounded in behavioural change theory that specifically target the motivators of behavioural change should be considered.

Anesthesia and the brain after concussion

PURPOSE OF REVIEW

To provide an overview of acute and chronic repeated concussion. We address epidemiology, pathophysiology, anesthetic utilization, and provide some broad-based care recommendations.

RECENT FINDINGS

Acute concussion is associated with altered cerebral hemodynamics. These aberrations can persist despite resolution of signs and symptoms. Multiple repeated concussions can cause chronic traumatic encephalopathy, a disorder associated with pathologic findings similar to some organic dementias. Anesthetic utilization is common following concussion, especially soon after injury, a time when the brain may be most vulnerable to secondary injury.

SUMMARY

Brain physiology may be abnormal following concussion and these abnormalities may persist despite resolutions of clinical manifestations. Those with recent concussion or chronic repeated concussion may be susceptible to secondary injury in the perioperative period. Clinicians should suspect concussion in any patient with recent trauma and strive to maintain cerebral homeostasis in the perianesthetic period.

The effect of diagnostic terminology on cognitive, emotional, and post-concussive sequelae following mild brain injury

Objective: We sought to determine whether the diagnostic terms 'mild traumatic brain injury (mTBI)' and 'concussion' result in differences in perceived cognitive, emotional, and post-concussive sequelae.Method: A total of 81 healthy university students (79% female; 69% of Asian descent) were randomly assigned to one of two conditions: mTBI (n = 41), or concussion (n = 40), and were instructed to simulate on a battery of cognitive (Neuropsychological Assessment Battery - Screening Module), emotional (Beck Anxiety Inventory, Beck Depression Inventory-II), and post-concussive (Rivermead Postconcussive Symptoms Questionnaire) measures.Results: There were no significant group differences between expected cognitive, emotional, or post-concussive consequences. However, both groups received poorer scores than the normative data.Conclusions: These results suggest that diagnostic terminology does not appear to influence anticipated recovery following mild brain injury. However, the presentation of information about the injury itself may impact recovery outcomes. This study provides preliminary support for the potential negative effects that may arise as a result of providing participants with non-evidence based information about mild brain injuries.

Using the Integrated Behavioral Model to Determine Sport-Related Concussion Reporting Intentions Among Collegiate Athletes

PURPOSE

A significant proportion of sport-related concussions goes unreported among adolescents, which can result in irreversible brain damage. It is critical to identify and intervene on factors that significantly impact concussion reporting.

METHODS

This study tests factors associated with collegiate athletes' intentions to (1) self-report concussion symptoms; (2) report another athlete's concussion symptoms; and (3) encourage others to report. Drawing on the Integrated Behavioral Model, predictors at the athlete level included perceived norms (bystander descriptive norms, injunctive norms, and subjective norms), attitudes (positive and negative expectancies about reporting and playing through a concussion and concussion reporting attitudes), personal agency (self-efficacy to recognize symptoms and communicate), and perceived coach communication. At the team level, coaches' self-reported communication was also included. Athletes (N = 1,858) and coaches (N = 254) at 16 colleges and universities completed Web-based surveys in 2016. Multilevel modeling accounted for the nesting of athletes within athletic team.

RESULTS

Bystander descriptive norms, positive reporting expectancies, concussion reporting attitudes, self-efficacy to communicate about a concussion, and athletes' perceptions of their coach's communication were positively associated with all three outcomes. By contrast, subjective norms were only positively associated with intentions to self-report and bystander reporting intentions, negative reporting expectancies were only associated with intentions to self-report, and positive and negative expectancies for playing through a concussion were only associated with intentions to self-report and bystander encouragement.

CONCLUSIONS

In sum, multiple factors within the Integrated Behavioral Model predict reporting intentions and underscore the complexity of athletes' concussion reporting behaviors and offer guidance for the development of prevention strategies.

A Review of Smartphone Applications for Persons With Traumatic Brain Injury: What Is Available and What Is the Evidence?

OBJECTIVES

To map the number and type of smartphone applications available for persons with traumatic brain injury (TBI), evaluate validity of app content, and investigate evidence for any claims made.

METHODS

We searched iTunes and Google Play and also completed a web search. The purpose of each app and any claims were extracted, and a search for best available evidence was performed.

RESULTS

Seventy apps met our inclusion criteria (35 related to assessment, 11 to education, 9 to treatment/management, 8 to impact sensors, and 7 to symptom tracking). To the best of our knowledge, no empirical research has been published to demonstrate that the use of any particular TBI-related app leads to clinically meaningful benefits compared with not using the app. Other problems include potential biases in self-report leading to possible app misuse, lack of references for app content, and inappropriate marketing to laypersons not trained to interpret the findings of tools validated for use by healthcare professionals.

CONCLUSIONS

The current evidence for benefit from using TBI-related apps is minimal. More collaborative research is needed among clinicians, scientists, and app developers to determine whether, and how, apps may be helpful to individuals at risk for or following TBI.

Delayed Symptom Onset Following Pediatric Sport-Related Concussion

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

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

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

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

Noncredible effort on the Nonverbal-Medical Symptom Validity Test (NV-MSVT): Impact on cognitive performance in pediatric mild traumatic brain injury

This study examined failure rates on the Nonverbal-Medical Symptom Validity Test (NV-MSVT) and its impact on cognitive performance in a sample of youths with mild traumatic brain injury (mTBI). Participants were 184 children and adolescents who presented to a multidisciplinary concussion clinic for a targeted neuropsychological evaluation. Performance Validity Tests (PVTs) were a part of the standard battery, including the NV-MSVT. Twenty-eight participants (15.2%) failed the NV-MSVT, none of whom displayed a genuine memory impairment profile (GMIP). Participants who failed the NV-MSVT performed significantly worse than those who passed the NV-MSVT on measures of IQ, memory, and immediate attention/working memory. There was no significant difference between groups on processing speed, sustained attention, cognitive flexibility, or sight word reading level. Aside from a slight difference in age, NV-MSVT failure was not impacted by demographic variables (sex, race), premorbid risk factors (pre-injury ADHD, learning disabilities, psychiatric diagnoses or treatment, developmental delays, or prior special education), injury-related variables (time since injury, positive neuroimaging findings, post-traumatic amnesia, number of prior mTBIs, etc.) or post-mTBI anxiety/depression. That said, participants who failed NV-MSVT endorsed significantly more severe postconcussive symptoms. These findings support the use of the NV-MSVT in neuropsychological evaluation of children and adolescents with mTBI.

Exploring the association between recent concussion, subconcussive impacts and depressive symptoms in male Australian Football players

Objectives

To explore the association between depressive symptoms and recent head-related trauma (diagnosed concussion, subconcussive impacts) in semiprofessional male Australian Football (AF) players.

Methods

Sixty-nine semiprofessional male players from a West Australian Football League (WAFL) club participated in the study (M_age=21.81, SD=2.91 years). Depressive symptoms were measured using the Centre for Epidemiological Studies Depression Scale. Injuries and potential confounding variables (eg, pre-existing mental health condition; alcohol or drug hangovers; experiencing a stressful event) were self-reported anonymously using the WAFL Injury Report Survey. Both tools were administered every 2-weeks over the first 22-weeks of the WAFL season. Controlling for potential confounding variables and other injuries, a repeated measures generalised estimating equations model assessed the risk of clinically relevant depressive symptoms occurring, when diagnosed concussion or subconcussive impacts were experienced.

Results

A total of 10 concussions and 183 subconcussive impacts were reported. Players who experienced a concussion were almost nine times more likely to experience clinically relevant depressive symptoms (OR 8.88, 95% CI 2.65 to 29.77, p<0.001). Although elevated, depressive symptoms following subconcussive impacts were not statistically significant (OR 1.13, 95% CI 0.67 to 1.92, p=0.641).

Conclusion

These findings indicate that semiprofessional AF athletes may be at risk of experiencing depressive symptoms after concussion. Severity (concussion vs subconcussive impacts) and dose (number of impacts) appear to have an important relationship with depressive symptom outcomes in this cohort and should be considered for further research and management of player welfare.

Less Than Half of Patients Recover Within 2 Weeks of Injury After a Sports-Related Mild Traumatic Brain Injury: A 2-Year Prospective Study

OBJECTIVE

To describe clinical recovery time and factors that might impact on recovery after a sports-related mild traumatic brain injury (SR-mTBI; concussion).

DESIGN

Prospective cohort study (level IV evidence).

SETTING

New Zealand Sports Concussion Clinic.

PARTICIPANTS

Eight hundred twenty-two patients presenting within 14 days of a SR-mTBI/concussion over a 2-year period.

MAIN OUTCOME MEASURES

Clinical recovery measured as number of days after injury.

INTERVENTIONS METHODS

Participants were assessed and managed using a standardized protocol consisting of relative rest followed by controlled cognitive and physical loading. A reassessment was performed 14 days after injury with initiation of an active rehabilitation program consisting of a subsymptom threshold exercise program ± cervicovestibular rehabilitation (if required) for participants who remained symptomatic. Participants were then assessed every 2 weeks until clinical recovery.

RESULTS

A total of 594 participants were eligible for analysis (mean age 20.2 ± 8.7 years, 77% males) and were grouped into 3 age cohorts: children (≤12 years), adolescents (13-18 years), and adults (≥19 years). Forty-five percent of participants showed clinical recovery within 14 days of injury, 77% by 4 weeks after injury, and 96% by 8 weeks after injury. There was no significant difference in recovery time between age groups. Prolonged recovery was more common in females (P = 0.001), participants with "concussion modifiers" (P = 0.001), and with increased time between injury and the initial appointment (P = 0.003).

CONCLUSIONS

This study challenges current perceptions that most people with a SR-mTBI (concussion) recover within 10 to 14 days and that age is a determinant of recovery rate. Active rehabilitation results in high recovery rates after SR-mTBI.

ImPACT Normative Data of Ethnically Diverse Adolescent Athletes

OBJECTIVE

The aim of this research was to develop preliminary norms for the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) administered to a large sample of adolescent athletes from diverse ethnic backgrounds.

DESIGN

A retrospective records review.

SETTING

Middle and high school athletic departments.

PARTICIPANTS

A total of 5741 male and female adolescent athletes in Hawaii, aged 13 to 18 years, in grades 9 to 12 were included in the study.

INDEPENDENT VARIABLES

Age, sex, ethnicity, and sport.

MAIN OUTCOME MEASURES

ImPACT Composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time, and Impulse Control) and Total Symptom score from baseline testing.

RESULTS

The results indicated statistically significant differences between age and sex groups, as well as between ethnic and sport groups.

CONCLUSIONS

The findings support the continued use of stratified norms for age and sex for ethnically diverse adolescent athletes. Comparisons of ethnic and sport groups deserve further investigation. When baseline scores are not available for postconcussion comparison, present observations tentatively support the cautious use of standard ImPACT norms with ethnically diverse athletes.

Student-athlete concussion disclosure and coach communication within collegiate athletics

Background

Between 1.6 and 3.8 million sports- and recreation-related concussions occur in the United States annually. Reports indicate that a significant number of athletes who have experienced symptoms of a potential sport-related concussion did not disclose their symptoms.

Aims

The purpose of this study was to investigate the impact of coach communication about concussion disclosure on student-athlete intentions to disclose symptoms of a concussion and encourage another student-athlete to disclose their concussion symptoms.

Methods

A total of 2881 student-athletes completed a web-based survey during Fall of 2016. Multiple linear regression was conducted to primarily investigate the relationship between coach communication and intentions to disclose concussion symptoms. Secondarily, biological sex, year in school, athletic division, and sport category was also assessed.

Results

Coach communication predicted greater intentions to disclose symptoms to their coach, athletic trainer/sports medicine sports medicine staff member and encourage another athlete to disclose their symptoms of a concussion. Biological sex and sport category also predicted intentions to disclose concussion symptoms.

Discussion

Findings from this study provide support for the important role coaches play in an athlete’s regarding concussion safety and introduces preliminary evidence suggesting the impact of coach communication on athlete intentions to disclose concussion symptoms to a coach or athletic trainer/sports medicine staff member.

Conclusion

Future studies and behavioral interventions ought to consider the inclusion of coach communication or other coach-related variables when exploring concussion disclosure among athletes.

Recent Preoperative Concussion and Postoperative Complications: A Retrospective Matched-cohort Study

BACKGROUND

Physiological alterations during the perianesthetic period may contribute to secondary neurocognitive injury after a concussion.

METHODS

Patients exposed to concussion and who received an anesthetic within 90 days were matched to unexposed patients without concussion. Intraoperative and postoperative events were compared. Subgroup analyses assessed relationships among patients with a concussion in the prior 30, 31 to 60, and 61 to 90 days and their respective unexposed matches. To facilitate identification of potential targets for further investigation, statistical comparisons are reported before, as well as after, correction for multiple comparisons.

RESULTS

Sixty concussion patients were matched to 176 unexposed patients. Before correction, 28.3% postconcussion versus 14.8% unexposed patients reported postanesthesia care unit pain score≥7 (P=0.02); 16.7% concussion versus 6.5% unexposed patients reported headache within 90 days of anesthesia (P=0.02) and 23.5% of patients who received surgery and anesthesia within 30 days of concussion experienced headache within 90 days of anesthesia compared with 7.1% in the unexposed group (P=0.01). Patients who experienced concussion and had anesthesia between 31 and 60 days after injury had a postanesthesia care unit Richmond Agitation and Sedation Scale score of -1.61±1.29 versus a score of -0.2±0.45 in unexposed patients (P=0.002). After adjusting the P-value threshold for multiple comparisons, the P-value for significance was instead 0.0016 for the overall cohort. Our study revealed no significant associations with application of adjusted significance thresholds.

CONCLUSIONS

There were no differences in intraoperative and postoperative outcomes in patients with recent concussion compared with unexposed patients. Before correction for multiple comparisons, several potential targets for further investigation are identified. Well-powered studies are warranted.

Patient, Injury, Assessment, and Treatment Characteristics and Return-to-Play Timelines After Sport-Related Concussion: An Investigation from the Athletic Training Practice-Based Research Network

OBJECTIVES

To describe the patient, injury, assessment and treatment characteristics, as well as return-to-play timelines and clinical findings at discharge for adolescent patients after sport-related concussion.

DESIGN

Retrospective analysis of electronic medical records.

SETTING

Athletic training facilities of secondary school members of the Athletic Training Practice-Based Research Network (AT-PBRN).

PATIENTS

In total, 1886 patient records were reviewed. [1204 (63.8%) male, 682 (36.2%) female, age = 15.3 ± 1.9 years, height = 169.5 ± 13.5 cm, mass = 70.3 ± 17.0 kg]. Patients were diagnosed with a concussion by an athletic trainer or team/directing physician.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Descriptive analysis of patient, injury, assessment, treatment, and participation status characteristics, as well as discharge information.

RESULTS

Injury demographic forms were completed for 1886 concussion cases. A concussion-specific evaluation form was completed for 55.9% (n = 1054) of cases. Treatment documentation was completed on 829 patients (44.0% of initial documented cases). Discharge forms were completed for 750 patients (40.0% of initial documented cases). Most cases were coded as 850.9-Concussion (85.5%, n = 642) and occurred during an in-season game (49.4%, n = 308). Time lost from competition was 24.9 ± 39.9 days.

CONCLUSIONS

Most concussion cases documented in this study were not on-field emergencies, as indicated by their normal clinical examinations and the lack of immediate referral to an emergency department. However, certain aspects of the clinical examination were often not assessed during the initial evaluation. These findings describe concussion assessment and recovery in adolescents and reinforce the need for a standardized approach to concussion assessment and appropriate documentation.

Descriptive Analysis of a Baseline Concussion Battery Among U.S. Service Academy Members: Results from the Concussion Assessment, Research, and Education (CARE) Consortium

Introduction

The prevalence and possible long-term consequences of concussion remain an increasing concern to the U.S. military, particularly as it pertains to maintaining a medically ready force. Baseline testing is being used both in the civilian and military domains to assess concussion injury and recovery. Accurate interpretation of these baseline assessments requires one to consider other influencing factors not related to concussion. To date, there is limited understanding, especially within the military, of what factors influence normative test performance. Given the significant physical and mental demands placed on service academy members (SAM), and their relatively high risk for concussion, it is important to describe demographics and normative profile of SAMs. Furthermore, the absence of available baseline normative data on female and non-varsity SAMs makes interpretation of post-injury assessments challenging. Understanding how individuals perform at baseline, given their unique individual characteristics (e.g., concussion history, sex, competition level), will inform post-concussion assessment and management. Thus, the primary aim of this manuscript is to characterize the SAM population and determine normative values on a concussion baseline testing battery.

Materials and Methods

All data were collected as part of the Concussion Assessment, Research and Education (CARE) Consortium. The baseline test battery included a post-concussion symptom checklist (Sport Concussion Assessment Tool (SCAT), psychological health screening inventory (Brief Symptom Inventory (BSI-18) and neurocognitive evaluation (ImPACT), Balance Error Scoring System (BESS), and Standardized Assessment of Concussion (SAC). Linear regression models were used to examine differences across sexes, competition levels, and varsity contact levels while controlling for academy, freshman status, race, and previous concussion. Zero inflated negative binomial models estimated symptom scores due to the high frequency of zero scores.

Results

Significant, but small, sex effects were observed on the ImPACT visual memory task. While, females performed worse than males (p < 0.0001, pη2 = 0.01), these differences were small and not larger than the effects of the covariates. A similar pattern was observed for competition level on the SAC. There was a small, but significant difference across competition level. SAMs participating in varsity athletics did significantly worse on the SAC compared to SAMs participating in club or intramural athletics (all p's < 0.001, η2 = 0.01). When examining symptom reporting, males were more than two times as likely to report zero symptoms on the SCAT or BSI-18. Intramural SAMs had the highest number of symptoms and severity compared to varsity SAMs (p < 0.0001, Cohen's d < 0.2). Contact level was not associated with SCAT or BSI-18 symptoms among varsity SAMs. Notably, the significant differences across competition level on SCAT and BSI-18 were sub-clinical and had small effect sizes.

Conclusion

The current analyses provide the first baseline concussion battery normative data among SAMs. While statistically significant differences may be observed on baseline tests, the effect sizes for competition and contact levels are very small, indicating that differences are likely not clinically meaningful at baseline. Identifying baseline differences and significant covariates is important for future concussion-related analyses to inform concussion evaluations for all athlete levels.

A Mobile Phone App for the Self-Management of Pediatric Concussion: Development and Usability Testing

BACKGROUND

Concussion is a common injury among Canadian children and adolescents that leads to a range of neurobehavioral deficits. However, noticeable gaps continue to exist in the management of pediatric concussion, with poor health outcomes associated with the inadequate application of best practice guidelines.

OBJECTIVE

The aim of this study was to describe the development and assess the usability of a mobile phone app to aid youth in the self-management of concussion. A secondary objective was to assess the usefulness of the app.

METHODS

An agile user-centered design approach was used to develop the technology, followed by a formative lab-based usability study for assessment and improvement proposals. Youths aged 10 to 18 years with a history of concussion and health care professionals involved in concussion management were recruited. This study included participants performing 12 tasks with the mobile phone app while using the think aloud protocol and the administration of the System Usability Scale (SUS), posttest questionnaire, and a semistructured interview.

RESULTS

A mobile phone app prototype called NeuroCare, an easily accessible pediatric concussion management intervention that provides easy access to expert-informed concussion management strategies and helps guide youth in self-managing and tracking their concussion recovery, was developed. A total of 7 youths aged between 10 and 18 years with a history of concussion and 7 health care professionals were recruited. The mean SUS score was 81.9, mean task success rates were greater than 90% for 92% (11/12) of the tasks, 92% (11/12) of tasks had a total error frequency of less than 11 errors, and mean task completion times were less than 2 min for 100% of the tasks.

CONCLUSIONS

Results suggest that participants rated this app as highly usable, acceptable to users, and that it may be useful in helping youth self-manage concussion.

Early Subthreshold Aerobic Exercise for Sport-Related Concussion: A Randomized Clinical Trial

IMPORTANCE

Sport-related concussion (SRC) is a significant public health problem without an effective treatment.

OBJECTIVE

To assess the effectiveness of subsymptom threshold aerobic exercise vs a placebo-like stretching program prescribed to adolescents in the acute phase of recovery from SRC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter prospective randomized clinical trial was conducted at university concussion centers. Male and female adolescent athletes (age 13-18 years) presenting within 10 days of SRC were randomly assigned to aerobic exercise or a placebo-like stretching regimen.

INTERVENTIONS

After systematic determination of treadmill exercise tolerance on the first visit, participants were randomly assigned to a progressive subsymptom threshold aerobic exercise or a progressive placebo-like stretching program (that would not substantially elevate heart rate). Both forms of exercise were performed approximately 20 minutes per day, and participants reported daily symptoms and compliance with exercise prescription via a website.

MAIN OUTCOMES AND MEASURES

Days from injury to recovery; recovery was defined as being asymptomatic, having recovery confirmed through an assessment by a physician blinded to treatment group, and returning to normal exercise tolerance on treadmill testing. Participants were also classified as having normal (<30 days) or delayed (≥30 days) recovery.

RESULTS

A total of 103 participants were included (aerobic exercise: n = 52; 24 female [46%]; stretching, n = 51; 24 female [47%]). Participants in the aerobic exercise group were seen a mean (SD) of 4.9 (2.2) days after the SRC, and those in the stretching group were seen a mean (SD) of 4.8 (2.4) days after the SRC. There were no differences in age, sex, previous concussions, time from injury, initial symptom severity score, or initial exercise treadmill test and physical examination results. Aerobic exercise participants recovered in a median of 13 (interquartile range [IQR], 10-18.5) days, whereas stretching participants recovered in 17 (IQR, 13-23) days (P = .009 by Mann-Whitney test). There was a nonsignificant lower incidence of delayed recovery in the aerobic exercise group (2 participants [4%] in the aerobic group vs 7 [14%] in the placebo group; P = .08).

CONCLUSIONS AND RELEVANCE

This is, to our knowledge, the first RCT to show that individualized subsymptom threshold aerobic exercise treatment prescribed to adolescents with concussion symptoms during the first week after SRC speeds recovery and may reduce the incidence of delayed recovery.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02710123.

Cortical Spreading Depression Denotes Concussion Injury

Cortical spreading depression (CSD) has been described after moderate-to-severe traumatic brain injury (TBI). It is uncertain, however, whether CSD occurs after mild, concussive TBI and whether it relates to brain pathology and functional outcome. Male C57BL6/J mice (n = 62) were subjected to closed head TBI with a 25 g weight (n = 11), 50 g weight (n = 45), or sham injury (n = 6). Laser Doppler flowmetry and optical intrinsic signal imaging were used to determine cerebral blood flow dynamics after concussive CSD. Functional deficits were assessed at baseline, 2 h, 24 h, and 48 h. TUNEL and Prussian blue staining were used to determine cell death and presence of cerebral microbleeds at 48 h. No CSD was observed in mice subjected to a 25 g weight drop whereas 58.9% of mice subjected to a 50 g weight drop developed a CSD. Mice with concussive CSD displayed significantly greater numbers of apoptotic cell profiles in the ipsilesional hemisphere compared with mice without a CSD that underwent the same 50 g weight drop paradigm (p < 0.05, each). All investigated animals had at least one cerebral microbleed (range 1 to 24). Compared with mice without a CSD, mice with a CSD had significantly more microbleeds in the traumatized hemisphere (p < 0.05, each) and showed impaired functional recovery (p < 0.05). Incidence of CSD after mild TBI depended on impact severity and was associated with histological and behavioral outcomes. These observations indicate that concussive CSD may serve as viable marker for concussion severity and provide novel avenues for outcome prediction and therapeutic decision making.

Efficacy of Tandem Gait to Identify Impaired Postural Control after Concussion

PURPOSE

The purpose was to evaluate tandem gait (TG), Balance Error Scoring System (BESS), and modified Balance Error Scoring System (mBESS) performance acutely after concussion in collegiate student-athletes. In addition, we sought to evaluate the psychometric properties of TG, including minimal detectable change (MDC), sensitivity, and specificity.

METHODS

Seventy-six National Collegiate Athletic Association student-athletes performed TG and BESS tests: 38 acutely after concussion and 38 controls. Participants were tested at baseline (time 1) and again acutely after concussion, or the following year for controls (time 2). Ten controls, tested simultaneously by two researchers, established a TG interrater minimal detectable change. A 2 × 2 mixed-design ANOVA compared each outcome variable. An receiver operating characteristic curve analysis was used to evaluate sensitivity, specificity, and area under the curve (AUC).

RESULT

There was a significant interaction (F = 8.757, P = 0.004) for TG whereby the concussion group was slower after concussion (10.59 ± 1.53 vs 11.80 ± 2.67 s), whereas there was no difference for controls (10.13 ± 1.72 vs 9.93 ± 1.85 s). There was no significant interaction for BESS (F = 0.235, P = 0.630) or mBESS (F = 0.007, P = 0.935). TG had a sensitivity of 0.632, a specificity of 0.605, and an AUC of 0.704. BESS had a sensitivity of 0.447, a specificity of 0.500, and an AUC of 0.508. mBESS had a sensitivity of 0.474, a specificity of 0.632, and an AUC of 0.535.

CONCLUSIONS

Participants completed TG significantly slower after concussion, whereas no change across time was detected for controls. In contrast, BESS and mBESS performances were similar at both testing times in both groups. Our AUC analysis was acceptable for TG, but a failure for both BESS and mBESS; thus, TG may be a useful alternative for clinicians conducting postconcussion postural control assessments.

Sensitivity of the Cogstate Test Battery for Detecting Prolonged Cognitive Alterations Stemming From Sport-Related Concussions

OBJECTIVE

To determine if the Cogstate test battery contains the requisite sensitivity to detect prolonged cognitive alterations.

METHODS

One hundred twenty collegiate athletes (71 with a history of concussion; 49 controls) completed the Cogstate test battery, to which we added a 2-back condition. In addition to the Cogstate clinical (transformed variables), we analyzed the raw data.

RESULTS

The clinical variables failed to reveal any group differences. Further, although the raw data failed to reveal group differences for tasks measuring lower-level cognition, group differences were observed for accuracy on the 1- and 2-back tasks, which require multiple aspects of higher cognition. The overall classification accuracy was higher using the raw data than the clinical variables. The combined sensitivity of the 1- and 2-back task was moderate and specificity was high.

CONCLUSIONS

These results suggest that using the raw scores over clinical variables increases the sensitivity of the test battery. Moreover, these results add another piece of evidence suggesting that concussive injuries are associated with subtle long-term alterations in aspects of higher cognition. Importantly, these deficits would have gone unobserved if we had relied solely on automated clinical variables. The current results further our scientific understanding of concussion and may be used to advance clinical practices.

Complicated Mild Traumatic Brain Injury at a Level I Pediatric Trauma Center: Burden of Care and Imaging Findings

OBJECTIVE

The aims of this study were: (1) to characterize mild traumatic brain injury (mTBI), mTBI with skull fracture, and complicated mTBI in school-aged children seen at a Level I pediatric trauma center and (2) to examine the nature of imaging findings seen in children with mTBI with skull fracture and those with complicated mTBI.

METHODS

A total of 1777 pediatric patients (male: 1193 or 67.1%; age = 11.1 ± 3.5 years) sustaining mTBI who presented to the Emergency Department or directly to the trauma service in the years 2010 to 2013 were identified and classified into mTBI (n = 1,319 or 74.2%), mTBI with skull fracture (n = 127 or 7.2%), and complicated mTBI (n = 331 or 18.6%). Patient characteristics and imaging findings were analyzed using descriptive statistics, Pearson's χ² test, Fisher's exact test, and logistic regression analysis.

RESULTS

In children with complicated mTBI, subdural hematoma (36.9%) was the most common finding. Of the 331 children with complicated mTBI, 241 (72.8%) had multiple findings compared with one (0.8%) of 127 children having mTBI with skull fracture (Fisher's exact P < 0.001), with logistic regression analysis revealing younger age as a potential risk factor (P < 0.01). Children sustaining a depressed or complex skull fracture were nearly twice as likely as those with simple, linear skull fracture to have intracranial abnormality.

CONCLUSIONS

Multiple radiographic findings in children sustaining mTBI with skull fracture or complicated mTBI are prevalent (72.8%), with younger age as a potential risk factor.

Risk Factors for Prolonged Symptoms of Mild Traumatic Brain Injury: A Pediatric Sports Concussion Clinic Cohort

OBJECTIVE

To examine predictors of prolonged symptom duration from mild traumatic brain injury (mTBI) in a pediatric sports medicine specialty clinic cohort as these predictors may be distinct in this population.

DESIGN

Retrospective chart review.

SETTING

Outpatient specialty clinic.

PATIENTS

Charts of 549 patients (age range: 10-18 years) with concussions were reviewed in an outpatient clinic that predominantly managed sports-related injuries (77.3%). Patients (n = 431) included in the final analysis met the criteria for mTBI and were symptomatic at their first visit.

ASSESSMENT OF RISK FACTORS

Patient history, injury, and recovery variables were evaluated.

MAIN OUTCOME MEASURES

Predictors of prolonged time to reach self-reported symptom recovery were evaluated using Cox proportional hazards.

RESULTS

Median time to symptom recovery of the 431 patients who presented to clinic with symptoms was 40 days (full clinic sample median = 34 days). Analyses identified 3 unique predictors of symptom recovery: loss of consciousness (LOC) [hazard ratio (HR) = 0.56, P < 0.0001], female sex (HR = 0.57, P < 0.0001), and concussion symptom score at first clinic visit (HR = 0.76, P < 0.0001).

CONCLUSIONS

Prolonged duration of mTBI symptoms in patients who present to a pediatric sports-based concussion clinic is related to initial symptom severity, female sex, and LOC.

Recent Advances in Pediatric Concussion and Mild Traumatic Brain Injury

Concussions after a head injury among children continues to be a substantial public health concern. An increasing number of concussions are being managed initially by primary care physicians. The diagnosis of concussion remains a clinical diagnosis despite the availability of ancillary tests such as computerized neuropsychological testing, advanced imaging, and blood biomarkers. Clinically, overlooking other injuries and comorbidities may lead to prolonged recovery for the patient. Addressing concussions in a multidisciplinary approach may help in reducing recovery time for patients. Retirement from sport in the pediatric population remains a controversial issue lacking evidenced-based studies.

Active recovery from concussion

PURPOSE OF REVIEW

Recent studies are challenging the utility of prolonged rest as treatment for concussion and postconcussion syndrome (PCS). The purpose of this paper is to review the evidence for active recovery from concussion and PCS.

RECENT FINDINGS

Emerging data identify the central role of autonomic nervous system (ANS) dysfunction in concussion pathophysiology. The exercise intolerance demonstrated by athletes after sport-related concussion may be related to abnormal ANS regulation of cerebral blood flow. As aerobic exercise training improves ANS function, sub-symptom threshold exercise treatment is potentially therapeutic for concussion. A systematic assessment of exercise tolerance using the Buffalo Concussion Treadmill Test has been safely employed to prescribe a progressive, individualized subthreshold aerobic exercise treatment program that can return patients to sport and work. Multiple studies are demonstrating the efficacy of an active approach to concussion management.

SUMMARY

Sustained rest from all activities after concussion, so-called 'cocoon therapy', is not beneficial to recovery. Evidence supports the safety, tolerability, and efficacy of controlled sub-symptom threshold aerobic exercise treatment for PCS patients. Further study should determine the efficacy and optimal timing, dose, and duration of subthreshold aerobic exercise treatment acutely after concussion because early intervention has potential to prevent PCS.

Use of Blood Biomarkers in the Assessment of Sports-Related Concussion-A Systematic Review in the Context of Their Biological Significance

OBJECTIVES

To critically review current knowledge on the positive and negative predictive value of blood biomarkers for concussion; to illustrate the clinical and biological contexts that help evaluate the use of these markers in sport-related traumatic brain injuries (TBIs).

METHODS

This systematic review was performed in accordance with PRISMA guidelines. We reviewed the measurement, clinical utility, endpoint, and biological significance of blood biomarkers in concussion.

RESULTS

A total of 4352 publications were identified. Twenty-six articles relating to blood biomarkers were included in the review. Four common blood biomarkers, namely S100B, tau, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP), were examined. Overall, the studies showed S100B measurement and use, either acutely or at several time points, can distinguish injured from noninjured patients with an uncertain degree of utility in predicting mortality. At present, S100B has largely become an acceptable biomarker of TBI; however, studies have begun to highlight the need to incorporate clinical symptoms instead of S100B concentration in isolation on the basis of inconsistent results and lack of specificity across published studies. Further research is needed to evaluate and validate the use of tau, NSE, and GFAP as a diagnostic aid in the management of concussion and TBI.

CONCLUSIONS

At present, blood biomarkers have only a limited role in the evaluation and management of concussion. Although several biomarkers of brain injury have been identified, continued research is required. S100B holds promise as the most clinically useful diagnostic biomarker. Blood biomarkers, in combination with other clinical data, such as head computed tomography, would maximize the diagnostic accuracy. The methodological limitations evident in blood biomarker research results in the need for the clinical utility of blood biomarker use in concussion to be further explored.

Cerebral Autoregulation Is Disrupted Following a Season of Contact Sports Participation

Repetitive subconcussive head impacts across a season of contact sports participation are associated with a number of deficits in brain function. To date, no research has investigated the effect of such head impact exposure on dynamic cerebral autoregulation (dCA). To address this issue, 179 elite, junior-level (age 19.6 ± 1.5 years) contact sport (ice hockey, American football) athletes were recruited for pre-season testing. Fifty-two non-concussed athletes returned for post-season testing. Fifteen non-contact sport athletes (age 20.4 ± 2.2) also completed pre- and postseason testing. dCA was assessed via recordings of beat-by-beat mean arterial pressure (MAP) and middle cerebral artery blood velocity (MCAv) using finger photoplethysmography and transcranial Doppler ultrasound, respectively, during repetitive squat-stand maneuvers at 0.05 and 0.10 Hz. Transfer function analysis was used to determine Coherence (correlation), Gain (response amplitude), and Phase (response latency) of the MAP-MCAv relationship. Results showed that in contact sport athletes, Phase was reduced (p = 0.027) and Gain increased (p < 0.001) at post-season compared to pre-season during the 0.10 Hz squat-stand maneuvers, indicating cerebral autoregulatory impairment in both the latency and magnitude of the response. Changes in Phase were greater in athletes experiencing higher numbers and severity of head impacts. By contrast, no changes in dCA were observed in non-contact sport controls. Taken together, these results demonstrate that repetitive subconcussive head impacts occurring across a season of contact sports participation are associated with exposure-dependent impairments in the cerebrovascular pressure-buffering system capacity. It is unknown how long these deficits persist or if they accumulate year-over-year.

Using sideline concussion tests in the emergency department

Purpose

Traumatic brain injury (TBI) is a significant cause of death and disability in the United States. Many patients with TBI are initially treated in the emergency department (ED), but there is no evidence-based method of detecting or grading TBI in patients who have normal structural neuroimaging. This study aims to evaluate the validity of two common sideline concussion tests. The Concussion Symptom Severity Score (CSSS) and modified Balance Error Scoring System (mBESS) tests are well-validated sideline tests for concussion, but have not been validated in the setting of non-sport-related concussion, in settings other than the sideline or athletic training room or in moderate or severe TBI.

Patients and methods

One hundred forty-eight subjects who had sustained a TBI within the previous 72 hours and 53 healthy control subjects were enrolled. CSSS and mBESS were administered. Clinical outcomes were followed up prospectively.

Results

The CSSS was collected in 147 TBI subjects but only 51 TBI subjects were able to complete the mBESS. The CSSS was collected for all 53 control subjects, and the mBESS was completed for 51 control subjects. The mean CSSS for TBI and control subjects was 32.25 and 2.70, respectively (P < 0.001). The average mBESS for TBI and control subjects was 7.43 and 7.20, respectively (P = 0.82). CSSS greater than 5.17 was 93.43% sensitive and 69.84% specific for TBI.

Conclusion

The mBESS is poorly tolerated and, among those who can complete the test, not sensitive to TBI in the ED. The CSSS is both sensitive to TBI and well tolerated.

The Role of Physical Activity in Recovery From Concussion in Youth: A Neuroscience Perspective

BACKGROUND AND PURPOSE

Concussion is a major public health concern and one of the least understood neurological injuries. Children and youth are disproportionally affected by concussion, and once injured, take longer to recover. Current guidelines recommend a period of physical and cognitive rest with a gradual progressive return to activity. Although there is limited high-quality evidence (eg, randomized controlled trials) on the benefit of physical activity and exercise after concussion, most studies report a positive impact of exercise in facilitating recovery after concussion. In this article we characterize the complex and dynamic changes in the brain following concussion by reviewing recent results from neuroimaging studies and to inform physical activity participation guidelines for the management of a younger population (eg, 14-25 years of age) after concussion.

SUMMARY OF KEY POINTS

Novel imaging methods and tools are providing a picture of the changes in the structure and function of the brain following concussion. These emerging results will, in the future, assist in creating objective, evidence-based pathways for clinical decision-making. Until such time, physical therapists should be aware that current neuroimaging evidence supports participation in physical activity after an initial and brief period of rest, and consider how best to incorporate exercise into rehabilitation to enhance recovery following concussion.

RECOMMENDATIONS FOR CLINICAL PRACTICE

It is important that physical therapists understand the neurobiological impact of concussion injury and recovery, and be informed of the scientific rationale for the recommendations and guidelines for engagement in physical activity.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A205).

Sport-Related Concussion Reporting and Coach-Athlete Attachment Among Collegiate Student-Athletes

Between 2001 and 2015, 3.4 million traumatic brain injury (TBI) occurrences in the U.S. were accounted for by sport participation. It is estimated between 12% and 60% of athletes delay seeking care after sustaining a concussion. Differences in sport-related concussion (SRC) reporting have been attributed to several different factors. Whereas prior research related to SRC reporting behavior focus on normative and competitive pressures to continue play, less attention is given to the interpersonal context in which reporting takes place. Grounded in attachment theory, this study investigated relationships between coach-athlete attachment and help-seeking behavior. Findings suggest that as coach-athlete anxiousness increases, not reporting increases. and as coach-athlete secureness increases, not reporting decreases. Logistic regression analyses indicate that secure coach attachment significantly predicts greater likelihood of SRC reporting. These findings underscore the important role coach-athlete relationships may have on care-seeking behaviors of student-athletes and can inform individual and group interventions promoting SRC reporting.

Active Rehabilitation of Concussion and Post-concussion Syndrome

Concussion is a physiological brain injury with physical, cognitive, and emotional sequelae. The macrophysiological insult to the brain affects the autonomic nervous system and its control of cerebral blood flow. Most patients recover within 2 weeks, but some do not. Persistence of symptoms beyond the generally accepted time frame for recovery is called post-concussion syndrome (PCS). PCS is not a single entity; it is a group of disorders that requires specific forms of therapy. Rest has been the mainstay of the treatment for concussion and PCS. This article discusses the rationale for the active treatment of concussion and PCS.

Lightheadedness After Concussion: Not All Dizziness is Vertigo

OBJECTIVE

To characterize the presence and degree of postconcussion lightheadedness in relation to postconcussion vertigo and dizziness, and to determine whether lightheadedness influences overall symptom duration.

DESIGN

Prospective, cohort design.

SETTING

Nationwide Children's Hospital, Sports Concussion Clinic.

PARTICIPANTS

Five hundred ten patients (9-19 years of age) within 30 days of concussion injury.

MAIN OUTCOME MEASURES

Patient ratings (scale 0-6) of multiple postconcussion symptoms including lightheadedness, vertigo, and dizziness, reported from the day of clinic evaluation and recalled from the day of concussion.

RESULTS

Postconcussion lightheadedness occurred commonly relative to vertigo. Lightheadedness was recalled more than vertigo (70.8% vs 48.6%, P < 0.001) on concussion day and reported more than vertigo (47.1% vs 24.1%, P < 0.001) on the day of clinic evaluation. Principal component analysis demonstrated strong correlations among lightheadedness, vertigo, balance difficulties, difficulty concentrating, mental fogginess, and difficulty remembering, relative to other postconcussion symptoms. When present on the day of clinic evaluation, these highly correlated symptoms predicted prolonged concussion recovery [P = 0.028; Hazard Ratio (HR) = 1.2]. Female sex (P = 0.04; HR = 1.23), emotional symptoms recalled from the day of concussion (P = 0.007; HR = 1.23), and cephalalgic symptoms (P < 0.001; HR = 1.34) reported on the day of clinic evaluation also predicted prolonged concussion recovery.

CONCLUSIONS

Not all postconcussion dizziness is vertigo. Postconcussion lightheadedness is common and, when present at the time of clinic evaluation, can influence concussion recovery.

CLINICAL RELEVANCE

Distinguishing postconcussion lightheadedness from vertigo may help to inform clinical treatment and concussion research design. This study adds to the growing body of evidence that supports an association between concussion and autonomic dysfunction.

Exertional Tolerance Assessments After Mild Traumatic Brain Injury: A Systematic Review

OBJECTIVE

To review the literature to identify and summarize strategies for evaluating responses to physical exertion after mild traumatic brain injury (mTBI) for clinical and research purposes.

DATA SOURCES

PubMed and EBSCOhost through December 31, 2016.

STUDY SELECTION

Two independent reviewers selected studies based on the following criteria: (1) inclusion of participants with mTBI/concussion, (2) use of a measurement of physiological or psychosomatic response to exertion, (3) a repeatable description of the exertion protocol was provided, (4) a sample of at least 10 participants with a mean age between 8 and 65 years, and (5) the article was in English. The search process yielded 2685 articles, of which 14 studies met the eligibility requirements.

DATA EXTRACTION

A quality assessment using a checklist was conducted for each study by 2 independent study team members and verified by a third team member. Data were extracted by one team member and verified by a second team member.

DATA SYNTHESIS

A qualitative synthesis of the studies revealed that most protocols used a treadmill or cycle ergometer as the exercise modality. Protocol methods varied across studies including differences in initial intensity determination, progression parameters, and exertion duration. Common outcome measures were self-reported symptoms, heart rate, and blood pressure.

CONCLUSIONS

The strongest evidence indicates that exertional assessments can provide important insight about mTBI recovery and should be administered using symptoms as a guide. Additional studies are needed to verify optimal modes and protocols for post-mTBI exertional assessments.

Postural Control and Head Impact Exposure in Youth Football Players: Comparison of the Balance Error Scoring System and a Force Plate Protocol

Postural control testing is often used by clinicians and athletic trainers to assess the health of athletes during recovery from a concussion. Characterization of postural control as a clinical tool for use with youth athletes is limited though. The objective of this study was to compare performance on the Balance Error Scoring System (BESS) and a force plate protocol at the beginning and end of a season of football within a cohort of 34 healthy youth football players (average age of 9.9 ± 0.6 y). A secondary aim was to investigate if changes in measures of balance from the postseason to the preseason were correlated with head impact exposure. Players completed testing at the beginning and end of the youth football season. There were no significant differences between BESS scores before the season and after the season (P = .54). Performance on the BESS was not associated with any of the center of pressure metrics considered in this study. No correlation was observed between measures of balance and head impact exposure for the season. Further research is required to determine the viability of postural control testing with this population.

Head Impact Exposure in Junior and Adult Australian Football Players

This study measured and compared the frequency, magnitude, and distribution of head impacts sustained by junior and adult Australian football players, respectively, and between player positions over a season of games. Twelve junior and twelve adult players were tracked using a skin-mounted impact sensor. Head impact exposure, including frequency, magnitude, and location of impacts, was quantified using previously established methods. Over the collection period, there were no significant differences in the impact frequency between junior and adult players. However, there was a significant increase in the frequency of head impacts for midfielders in both grades once we accounted for player position. A comparable amount of head impacts in both junior and adult players has implications for Australian football regarding player safety and medical coverage as younger players sustained similar impact levels as adult players. The other implication of a higher impact profile within midfielders is that, by targeting education and prevention strategies, a decrease in the incidence of sports-related concussion may result.

What factors must be considered in ‘return to school’ following concussion and what strategies or accommodations should be followed? A systematic review

Objective

To evaluate the evidence regarding (1) factors affecting return to school (RTS) and (2) strategies/accommodations for RTS following a sport-related concussion (SRC) in children and adolescents.

Design

A systematic review of original studies specifically addressing RTS following concussion in the paediatric and sporting context.

Data sources

MEDLINE (Ovid), Embase (Ovid), PsycInfo (Ovid) electronic databases and the grey literature OpenGrey, ClinicalTrials.gov and Google Advanced.

Eligibility criteria

Studies were included if they were original research on RTS following SRC in children aged 5–18 years published in English between 1985 and 2017.

Results

A total of 180 articles were identified; 17 articles met inclusion criteria. Several factors should be considered for RTS after concussion, including: symptomatology; rest following injury; age/grade; and course load. On RTS after concussion, 17%–73% of students were provided academic accommodations or experienced difficulty with RTS. Students were more likely to obtain academic accommodations in schools with a concussion policy if they had a medical RTS letter and had regular medical follow-up after concussion.

Conclusions

Schools should have a concussion policy and offer individualised academic accommodations to students recovering from SRC on RTS; a medical letter should be provided to facilitate provision/receipt of academic accommodations; students should have early, regular medical follow-up following SRC to help with RTS and monitor recovery; students may require temporary absence from school after SRC; clinicians should assess risk factors/modifiers that may prolong recovery and require more intensive academic accommodations.

PROSPERO registration number

CRD42016039184.

Returning Adolescents to Driving after Sports-Related Concussions: What Influences Physician Decision-Making

OBJECTIVE

To determine which data collected on an initial patient clinic visit for a sports-related concussion (SRC) might influence physicians to clear an adolescent to return to drive (RTD) after injury.

STUDY DESIGN

Retrospective cohort study of 189 adolescents with a SRC referred to a hospital-based concussion clinic between June 1, 2015, and May 31, 2016. Subjects were ≥16 years with a valid driver's license (median age = 16, IQR [16, 17]). Concussion evaluations included Post-Concussion Symptom Scale, modified Balance Error Scoring System, and postinjury computerized neurocognitive testing (CNT). Clearance for RTD was the main outcome. Statistical comparisons were conducted with Mann-Whitney U and χ² tests and logistic regression.

RESULTS

In multivariable analysis, odds of being fully cleared to drive were 5.9-fold greater among patients who were administered CNT. Stated symptoms of "headache" and "sensitivity to light" were statistically significantly associated with RTD clearance. For a subset of 113 individuals undergoing CNT, each additional 10-millisecond decrease in simple reaction time was associated with 9% greater odds of being cleared to drive. Each additional 10-millisecond decrease in choice reaction time was associated with 4% greater odds of being cleared to drive.

CONCLUSIONS

CNT and associated reaction time measures may facilitate a physician's objective decision-making. Making a RTD determination for adolescents recovering from an SRC should be a core component of a physician's assessment.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Sensitivity and Specificity of the Modified Balance Error Scoring System in Concussed Collegiate Student Athletes

OBJECTIVE

To assess the efficacy of the modified Balance Error Scoring System (mBESS) compared with the Balance Error Scoring System (BESS) in an acutely concussed population.

DESIGN

Prospective observational study.

SETTING

University athletic training room.

PATIENTS

Thirty-five collegiate student-athletes (18 Female, 18.9 ± 0.8 year old, height: 1.71 ± 0.12 m, weight: 76.3 ± 24.1 kg) with diagnosed concussions and baseline BESS/mBESS tests.

INTERVENTIONS

All participants completed the BESS and mBESS on the day after the concussion (acute) and were retested daily until their BESS score achieved baseline value (recovery).

MAIN OUTCOME MEASURES

The number of errors committed during the BESS and mBESS at each time point were recorded. The sensitivity and specificity of the BESS and mBESS compared with the baseline test was calculated for acute and recovery as well as the mBESS compared with the BESS.

RESULTS

At acute, the sensitivity of the BESS and mBESS were 60.0% and 71.4%, respectively. Relative to mBESS baseline, 60% of participants were misclassified at either acute or recovery.

CONCLUSIONS

The mBESS had higher sensitivity at acute and identified lingering deficits at BESS recovery. Use of the mBESS is likely to produce different results than the BESS; however, the clinical implications of this warrant further investigation.

BTrackS Balance Test for Concussion Management is Resistant to Practice Effects

OBJECTIVE

Recent guidelines advocate for ongoing balance testing in the assessment of management of concussion injuries. This study sought to determine whether the Balance Tracking System (BTrackS) provides stable balance results over repeated administration and, thus, is a reliable tool for concussion management.

DESIGN

Repeated measures and test-retest reliability.

SETTING

University Biomechanics Laboratory.

PARTICIPANTS

Random sample of 20 healthy young adults.

INTERVENTIONS

Force plate balance testing using BTrackS on days 1, 3, 8, and 15.

MAIN OUTCOME MEASURES

Practice-induced changes in the average center of pressure excursion over 4 repeated administrations of the BTrackS Balance Test (BBT). Test-retest reliability of center of pressure excursion from day 1 to day 15.

RESULTS

No significant practice-induced balance differences were found across testing days (P > 0.4), and test-retest reliability of the BBT was excellent from day 1 to day 15 (R 0.92).

CONCLUSIONS

These findings indicate that the BBT does not elicit a practice effect over repeat administrations. BTrackS provides excellent reliability and objectivity, which can increase clinician accuracy when monitoring sport-related concussions.

Longitudinal Improvement in Balance Error Scoring System Scores among NCAA Division-I Football Athletes

The Balance Error Scoring System (BESS) is a commonly used concussion assessment tool. Recent studies have questioned the stability and reliability of baseline BESS scores. The purpose of this longitudinal prospective cohort study is to examine differences in yearly baseline BESS scores in athletes participating on an NCAA Division-I football team. NCAA Division-I freshman football athletes were videotaped performing the BESS test at matriculation and after 1 year of participation in the football program. Twenty-three athletes were enrolled in year 1 of the study, and 25 athletes were enrolled in year 2. Those athletes enrolled in year 1 were again videotaped after year 2 of the study. The paired t-test was used to assess for change in score over time for the firm surface, foam surface, and the cumulative BESS score. Additionally, inter- and intrarater reliability values were calculated. Cumulative errors on the BESS significantly decreased from a mean of 20.3 at baseline to 16.8 after 1 year of participation. The mean number of errors following the second year of participation was 15.0. Inter-rater reliability for the cumulative score ranged from 0.65 to 0.75. Intrarater reliability was 0.81. After 1 year of participation, there is a statistically and clinically significant improvement in BESS scores in an NCAA Division-I football program. Although additional improvement in BESS scores was noted after a second year of participation, it did not reach statistical significance. Football athletes should undergo baseline BESS testing at least yearly if the BESS is to be optimally useful as a diagnostic test for concussion.

Alpha desynchronization/synchronization during working memory testing is compromised in acute mild traumatic brain injury (mTBI)

Diagnosing and monitoring recovery of patients with mild traumatic brain injury (mTBI) is challenging because of the lack of objective, quantitative measures. Diagnosis is based on description of injuries often not witnessed, subtle neurocognitive symptoms, and neuropsychological testing. Since working memory (WM) is at the center of cognitive functions impaired in mTBI, this study was designed to define objective quantitative electroencephalographic (qEEG) measures of WM processing that may correlate with cognitive changes associated with acute mTBI. First-time mTBI patients and mild peripheral (limb) trauma controls without head injury were recruited from the emergency department. WM was assessed by a continuous performance task (N-back). EEG recordings were obtained during N-back testing on three occasions: within five days, two weeks, and one month after injury. Compared with controls, mTBI patients showed abnormal induced and evoked alpha activity including event-related desynchronization (ERD) and synchronization (ERS). For induced alpha power, TBI patients had excessive frontal ERD on their first and third visit. For evoked alpha, mTBI patients had lower parietal ERD/ERS at the second and third visits. These exploratory qEEG findings offer new and non-invasive candidate measures to characterize the evolution of injury over the first month, with potential to provide much-needed objective measures of brain dysfunction to diagnose and monitor the consequences of mTBI.