Sport-related concussion: factors associated with prolonged return to play

Influence of Preexisting Conditions and Concussion History on Postconcussion Symptom Severity and Recovery Time in Collegiate Athletes

Mental health conditions and concussion history reported by a collegiate athlete may contribute to prolonged recovery and symptom severity after concussion. This work examined the potential associations among concussion history, preexisting conditions, and sex relative to initial symptom severity and recovery duration following sport-related concussion (SRC) in a cohort of Division 1 National Collegiate Athletic Association athletes. This prospective cohort study analyzed symptom severity, recovery, and return-to-play (RTP) times reported post-SRC using data collected as part of the Pac-12 Concussion Assessment, Research and Education Affiliated Program and Health Analytics Program. Health history questionnaires that included self-reported history of preexisting conditions were completed at baseline. When consented athletes were diagnosed with a concussion, daily postconcussion symptom scores were evaluated until an athlete was clinically determined to be asymptomatic. Generalized linear and Cox proportional hazards models were used to determine associations between preexisting conditions and recovery and RTP times. Ninety-two concussions met inclusion criteria. Notable differences in initial symptom severity existed between females and males who had mood disorders (effect size [d] = 0.51) and attention-deficit hyperactivity disorder (ADHD; d = 0.93). The number of previous concussions was a strong predictor of athletes reporting preexisting mood disorders, depression, anxiety, and ADHD (p = 0.008-0.04). Females with ≥2 previous concussions required more days to RTP than males (d = 0.31-0.72). Weekly recovery and RTP probabilities substantially differed between athletes who did or did not have learning disorders (LDs; hazard ratio [HR]Recovery = 0.32, HRRTP = 0.22, d = 1.96-2.30) and ADHD (HRRecovery = 3.38, HRRTP = 2.74, d = 1.71-4.14). Although no association existed between concussion history and acute symptom severity, collegiate athletes with a history of concussion had higher probabilities of reporting depression, mood disorders, anxiety, and ADHD. Having ADHD or LDs likely strongly affects time to recovery and RTP for collegiate athletes.

Protective effects of early exercise on neuroinflammation, and neurotoxicity associated by traumatic brain injury: a behavioral and neurochemical approach

OBJECTIVE

The benefits of exercise in TBI have been proven. However, the time-dependent effects of exercise initiation and the involved mechanisms are controversial. We investigated the effects of preconditioning, continuous, early, and delayed treadmill exercise on motor behavior, brain edema, inflammation, and oxidative stress in experimental traumatic brain injury (TBI).

MATERIALS AND METHODS

48 male rats were assigned into two groups: sedentary control (Sham and TBI) and exercise groups: 1MB (preconditioning, initiation beginning at 1 month before trauma), 1MBA (continuous, initiation beginning at 1 month before and continuing 1 month after trauma), 24hA (early, initiation beginning at 24 h after trauma), and 1WA (delay, initiation beginning at 1 week after trauma). The rats in exercise groups were forced to run on a treadmill five days a week for 30 min per day. Rotarod and open file were used to assess motor behavior. ELISA was also used to measure total antioxidant capacity (TAC), tumor necrosis factor-alpha (TNF-α), and malondialdehyde (MDA) in serum and CSF.

RESULTS

Exercise significantly decreased neurological impairments, motor deficits, and apoptosis compared with the sedentary group. Early (within 24 h) and ongoing (1 MBA) exercise significantly improved motor behavior after TBI. In addition, these exercise programs inhibited brain edema and the number of apoptotic cells. MDA and TNF-α levels increased in all exercise groups, but the effects were greater after early exercise than after delayed exercise, resulting in a significant decrease in TAC levels in serum and CSF. We discovered a positive correlation between MDA, TAC, and TNF-α concentration in serum and CSF.

CONCLUSION

Our finding suggests that early exercise (24hA) and 1MBA groups afford neuroprotection and reduce the second injury consequence, probably by reducing neuronal apoptosis and oxidative stress.

Management of concussion symptoms utilizing Mechanical Diagnosis and Therapy: a case series

OBJECTIVE

Concussions are a common condition in athletes leading to symptoms including headache, dizziness, and sometimes vestibular deficits. Concussion management typically involves rest and a gradual return to activity among other interventions. This case series includes three patients who were evaluated using Mechanical Diagnosis and Therapy (MDT) after sport-related injuries involving concussion-like symptoms. MDT is a system of evaluating patients using repeated movements and sustained positions to assess symptomatic and mechanical changes.

RESULTS

Patients in this case series demonstrated rapid reduction of symptoms using variations of repeated cervical movements and sustained positions, which enabled them to return to play with a lasting resolution of symptoms.

DISCUSSION/CONCLUSION

This highlights the importance of a classification system for the appropriate treatment of these cases who did not require management using concussion protocol, as they were classified as cervical derangement.

Examining the role of depression on the relationship between performance-based and self-reported cognitive functioning after sport-related concussion

OBJECTIVE

Little is known about the relationship between neuropsychological test performance, cognitive symptom reporting, and depressive symptoms after sport-related concussion. Accordingly, this cross-sectional study examined these relationships in collegiate athletes. It was hypothesized that depressive symptoms would moderate and mediate the relationship between performance-based and self-reported cognitive functioning after concussion.

METHODS

After sustaining a sport-related concussion, 110 collegiate athletes completed a neuropsychological battery, the Post-Concussion Symptoms Scale, and the Beck Depression Inventory-Fast Screen. Neuropsychological test performance, depressive symptoms, and their interactions were entered into distinct hierarchical linear regression analyses with self-reported cognition as the dependent variable to assess moderation. Mediation was analyzed using the PROCESS macro with 5000 bootstrap samples and a 95% confidence interval.

RESULTS

There was a significant interaction between the mean memory composite and depressive symptoms when predicting cognitive symptom reporting, p = 0.047. Simple effects tests revealed that for athletes who had a lower memory composite score, an increase in depressive symptoms led to an increase in self-reported cognitive dysfunction, p < 0.001, ηp2 = 0.11. Depressive symptoms partially mediated the relationship between the memory composite and cognitive symptom reporting, indirect effect = -0.26, 95%CI[-0.58,0.001], but this relationship was not found for any other neurocognitive domain.

CONCLUSIONS

For tests of memory, depressive symptoms moderated and partially mediated the relationship between performance-based and self-reported cognitive functioning after sport-related concussion. Athletes reporting high depressive symptoms and cognitive dysfunction may need more comprehensive evaluations to inform return-to-play decisions, and depression could be a treatment target for athletes who report high levels of cognitive dysfunction after concussion.

Trajectories of Daily Postconcussion Symptoms in Children

OBJECTIVES

To identify trajectories of daily postconcussion symptoms (PCS) from the acute postinjury period to symptom resolution among concussed children and examine demographic factors and acute PCS associated with the identified symptom trajectories.

SETTING AND PARTICIPANTS

Seventy-nine participants with a concussion were enrolled within 72 hours of injury and completed a daily survey that assessed PCS from enrollment until symptom resolution.

DESIGN

This was a prospective cohort study among concussed children aged 11-17 years.

MAIN MEASURES

Children rated their concussion symptoms daily using the Post-Concussion Symptom Scale. Symptom duration was assessed using participants' date of symptom resolution and coded as a dichotomous variable: (1) PCS duration 14 days or less or (2) PCS duration longer than 14 days.

RESULTS

Of the 79 participants, most were male ( n = 53, 67%), injured during a sporting activity ( n = 67, 85%), or had PCS that persisted for more than 14 days post-injury ( n = 41, 52%). Group-based trajectory modeling yielded 4 trajectory groups: (1) low acute/resolved PCS ( n = 39, 49%), (2) moderate/persistent PCS ( n = 19, 24%), (3) high acute/persistent PCS ( n = 13, 16%), and (4) high acute/resolved PCS ( n = 8, 10%). No significant associations were found between demographic factors and the trajectory group. A higher symptom burden at injury was associated with an increased odds of being in the high acute/resolved or high acute/persistent recovery groups than being in the low acute/resolved group (odds ratio [OR] 1.39, 95% CI = 1.11-1.74; OR = 1.33, 95% CI = 1.11-1.60, respectively), as was a higher symptom severity at injury (OR = 1.09, 95% CI = 1.03-1.15; OR = 1.06, 95% CI = 1.02-1.11, respectively).

CONCLUSION

Our findings may help clinicians identify concussed children on slower recovery trajectories, and implement early, individualized treatment plans that foster optimal recovery for concussed children.

Do Sport-Related Concussions Later in the Season Take Longer to Recover From?

OBJECTIVE

In a cohort of high-school football athletes with sport-related concussion (SRC), we sought to investigate the role of seasonality, defined as time of injury during a season, on recovery.

DESIGN

Retrospective cohort study.

SETTING

Regional sport concussion center.

PARTICIPANTS

High-school football athletes ages 14 to 19 -years old who sustained an SRC from 11, 2017 to 04, 2022.

INTERVENTION

Athletes were divided into 3 groups based on seasonality: early, middle, and late season.

MAIN OUTCOME MEASURES

The primary outcomes were initial Post-Concussion Symptom Scale score and recovery, as defined by time to return-to-learn (RTL), symptom resolution, and return-to-play (RTP). Descriptive statistics, analysis-of-variance, t tests, and multivariable regressions were performed.

RESULTS

Of our cohort of 273 high-school football players who sustained an SRC, 97 (35.5%) sustained an SRC during early season, 107 (39.2%) during middle season, and 69 (25.3%) during late season. Compared with late-season concussions, early-season concussions took less days to symptom resolution (early = 11.5 ± 12.9 vs late = 25.5 ± 27.0, P = 0.03), but no differences were found in days to RTL (early = 5.3 ± 4.8 vs late = 7.2 ± 15.8, P = 0.51) and RTP (early = 13.5 ± 11.8 vs late = 23.0 ± 22.8, P = 0.08). Seasonality was not a significant predictor for any recovery metric in multivariable regressions.

CONCLUSION

Sport-related concussions occurring in the early third of the season took significantly less time to symptom resolution than those occurring in the later third of the season; however, this was not statistically significant in multivariable analyses. No association was observed between seasonality and time to RTL and RTP. A trend of worse recovery with concussions later in the season may be present.

Examining Whether Loss of Consciousness Is Associated With Worse Performance on the SCAT5 and Slower Clinical Recovery After Concussion in Professional Athletes

Video surveillance has almost universally been employed by professional sports to identify signs of concussion during competition. This study examined associations between video-identified possible loss of consciousness (LOC), acute concussion evaluation findings, and recovery time in concussed professional rugby league players. Medical personnel and sideline video operators identified head impact events sustained during three seasons of National Rugby League (NRL) matches to determine the need for further medical evaluation. If a concussion was suspected, players were removed from play and underwent a Head Injury Assessment, including the Sports Concussion Assessment Tool, Fifth Edition (SCAT5). Video footage was later examined to identify signs of possible LOC (i.e., observed LOC, no protective action in the fall, and unresponsiveness or lying motionless). Possible LOC was identified in 99 of the 1706 head impact events (5.8%). The median duration of apparent unresponsiveness was 4.2 sec (M = 7.4, standard deviation [SD] = 12.8, interquartile range [IQR] = 2.5-6.6). In the 661 athletes for whom SCAT5 data were available, those with possible LOC endorsed more SCAT5 symptoms and performed worse on Maddocks questions, Standardized Assessment of Concussion (SAC) total scores, orientation, immediate recall, concentration, and delayed recall. For the 255 players with medically diagnosed concussions, SCAT5 data were available for 245. Concussed players with possible LOC performed significantly worse on Maddocks questions. However, there were no group differences in SCAT5 symptom endorsement, SAC total scores, orientation, immediate recall, concentration, delayed recall, or the modified version of the Balance Error Scoring System (mBESS) total errors. Further, the presence or absence of possible LOC was not associated with number of games missed or time to medical clearance for match play. The duration of possible LOC was not associated with the number of games missed or time to medical clearance for match play. According to video review in NRL players, brief LOC might be more common than previously thought. The present study reveals possible LOC is not predictive of missed games or time to recover following concussion.

Race, ethnicity, and clinical outcome following sport-related concussion: a systematic review

Introduction

This systematic review examined whether race or ethnicity are associated with clinical outcomes (e.g., time to return to school/sports, symptom duration, vestibular deficits, and neurocognitive functioning) following sport-related concussion among child, adolescent, or college-aged student athletes. Additionally, this review assessed whether the existing literature on this topic incorporated or included broader coverage of social determinants of health.

Methods

The online databases PubMed, MEDLINE®, PsycINFO®, CINAHL, Cochrane Library, EMBASE, SPORTDiscus, Scopus, and Web of Science were searched.

Results

A total of 5,118 abstracts were screened and 12 studies met inclusion criteria, including 2,887 youth and young adults. Among the included articles, only 3 studies (25%) examined whether race and ethnicity were associated with outcomes following concussion as a primary objective. None of the studies assessed the association between social determinants of health and outcomes following concussion as a primary objective, although 5 studies (41.7%) addressed a social determinant of health or closely related topic as a secondary objective.

Discussion

Overall, the literature to date is extremely limited and insufficient for drawing conclusions about whether race or ethnicity are categorically associated with outcomes from sport-related concussion, or more specifically, whether there are socioeconomic, structural, or cultural differences or disparities that might be associated with clinical outcome.

Systematic review registration

identifier: PROSPERO, CRD42016041479, CRD42019128300.

When should an athlete retire or discontinue participating in contact or collision sports following sport-related concussion? A systematic review

OBJECTIVE

To systematically review the scientific literature regarding factors to consider when providing advice or guidance to athletes about retirement from contact or collision sport following sport-related concussion (SRC), and to define contraindications to children/adolescent athletes entering or continuing with contact or collision sports after SRC.

DATA SOURCES

Medline, Embase, SPORTSDiscus, APA PsycINFO, CINAHL and Cochrane Central Register of Controlled Trials were searched systematically.

STUDY ELIGIBILITY CRITERIA

Studies were included if they were (1) original research, (2) reported on SRC as the primary source of injury, (3) evaluated the history, clinical assessment and/or investigation of findings that may preclude participation in sport and (4) evaluated mood disturbance and/or neurocognitive deficits, evidence of structural brain injury or risk factors for increased risk of subsequent SRC or prolonged recovery.

RESULTS

Of 4355 articles identified, 93 met the inclusion criteria. None of the included articles directly examined retirement and/or discontinuation from contact or collision sport. Included studies examined factors associated with increased risk of recurrent SRC or prolonged recovery following SRC. In general, these were low-quality cohort studies with heterogeneous results and moderate risk of bias. Higher number and/or severity of symptoms at presentation, sleep disturbance and symptom reproduction with Vestibular Ocular Motor Screen testing were associated with prolonged recovery and history of previous concussion was associated with a risk of further SRC.

CONCLUSION

No evidence was identified to support the inclusion of any patient-specific, injury-specific or other factors (eg, imaging findings) as absolute indications for retirement or discontinued participation in contact or collision sport following SRC.

PROSPERO REGISTRATION NUMBER

CRD42022155121.

Primary and Secondary Risk Factors Associated With Concussion Symptom Clusters in Collegiate Athletes: Results From the NCAA-DoD Grand Alliance CARE Consortium

Background

There is a broad and diverse range of symptoms after a concussion, from irritability to nausea. This heterogeneity of symptoms is a challenge for clinicians managing the different presentations among injuries. Prior research has investigated the structure of postconcussive symptoms to determine if they can be grouped into clusters of related symptoms.

Purpose/Hypothesis

The purpose of this study was to identify symptom clusters during the acute phase after a sports-related concussion using exploratory factor analysis and to understand the relationship between risk factors for postconcussion symptoms (ie, demographics, injury characteristics, mental health, and sleep qualities) and different symptom clusters. We hypothesized that certain factors would be predictive of specific symptom clusters.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Collegiate athletes (N = 1104) from the Concussion, Assessment, Research, and Education (CARE) Consortium completed the Sport Concussion Assessment Tool-Third Edition symptom assessment tool 24 to 48 hours after concussion. Exploratory factor analysis was conducted on the symptom evaluation to determine symptom clusters 24 to 48 hours after concussion. Regression analysis was used to examine the effects of pre- and postinjury characteristics.

Results

Exploratory factor analysis revealed a 4-cluster structure for acute postconcussive symptoms that explained 62% of the variance in symptom reporting: vestibular-cognitive, migrainous, cognitive fatigue, and affective. Delayed reporting, less sleep before assessment, female sex, and being hurt outside of competition (during practice/training) was correlated with increased symptoms for 4 symptom clusters. Depression predicted higher vestibular-cognitive and affective symptoms. Amnesia was correlated with higher vestibular-cognitive and migrainous symptoms, whereas migraine history was associated with more migrainous and affective symptoms.

Conclusion

Symptoms can be grouped into 1 of 4 distinct clusters. Certain variables were associated with increased symptoms across multiple clusters and may be indicative of greater injury severity. Other factors (ie, migraine history, depression, amnesia) were associated with a more specific symptom presentation and may be mechanistically related to concussion outcomes and biological markers.

Risk of Migraine after Traumatic Brain Injury and Effects of Injury Management Levels and Treatment Modalities: A Nationwide Population-Based Cohort Study in Taiwan

Traumatic brain injury (TBI) causes several long-term disabilities, particularly headaches. An association between TBI and subsequent migraine has been reported. However, few longitudinal studies have explained the link between migraine and TBI. Moreover, the modifying effects of treatment remain unknown. This retrospective cohort study used records from Taiwan's Longitudinal Health Insurance Database 2005 to evaluate the risk of migraine among patients with TBI and to determine the effects of different treatment modalities. Initially, 187,906 patients, aged ≥ 18 years, who were diagnosed as TBI in 2000, were identified. In total, 151,098 patients with TBI and 604,394 patients without TBI were matched at a 1:4 ratio according to baseline variables during the same observation period. At the end of follow-up, 541 (0.36%) and 1491 (0.23%) patients in the TBI and non-TBI groups, respectively, developed migraine. The TBI group exhibited a higher risk of migraine than the non-TBI group (adjusted HR: 1.484). Major trauma (Injury Severity Score, ISS ≥ 16) was associated with a higher migraine risk than minor trauma (ISS < 16) (adjusted HR: 1.670). However, migraine risk did not differ significantly after surgery or occupational/physical therapy. These findings highlight the importance of long-term follow-up after TBI onset and the need to investigate the underlying pathophysiological link between TBI and subsequent migraine.

Systematic Review of Pre-injury Migraines as a Vulnerability Factor for Worse Outcome Following Sport-Related Concussion

Background

Individuals with migraine disorders may be affected differently by concussions compared to individuals without migraine disorders. Prior studies on this topic have had mixed results. The purpose of this study was to systematically examine clinical outcomes following a sport-related concussion in athletes who have a pre-injury history of migraines.

Methods

All studies published prior to 15 May 2021 that examined pre-injury migraines as a possible predictor of clinical recovery from concussion were included. The search included (i) sport/athlete-related terms, (ii) concussion-related terms, and (iii) diverse predictor/modifier terms. After removing duplicates, 5,118 abstracts were screened, 538 full-text articles were reviewed, and 27 articles were included for narrative synthesis without meta-analysis (n = 25 with unique samples). Risk of bias was assessed using the domain-based Quality In Prognosis Studies (QUIPS) tool.

Results

Most studies did not find pre-injury migraines to be associated with concussion outcome, but several of these studies had small or very small sample sizes, as well as other methodological weaknesses. Risk of bias varied greatly across studies. Some of the larger, better-designed studies suggested pre-injury migraines may be a risk factor for worse concussion outcome. Most articles examined pre-injury migraines as an exploratory/secondary predictor of concussion outcome; very few were designed to examine migraine as the primary focus of the study. Migraine history was predominantly based on self-report and studies included minimal information about migraine (e.g., age of onset, frequency/severity, past treatment). Effect sizes were usually not reported or able to be calculated from reported study data.

Conclusion

There is some evidence to suggest that pre-injury migraines may be a vulnerability factor for a worse outcome following concussion, with studies having the lowest risk of bias reporting a positive association. Future studies should focus on improving methodological quality when assessing the relationship between pre-injury migraines and concussion outcome and better characterizing pre-injury migraine status.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019128292, identifier: PROSPERO 2019 CRD42019128292.

Factors Associated With a Prolonged Time to Return to Play After a Concussion

BACKGROUND

Prognosticating recovery times for individual athletes with a concussion remains a challenge for health care providers. Several preinjury and postinjury factors have been proposed to be predictive of prolonged return-to-play (RTP) times, but the data in this area are still sparse.

PURPOSES

This study aimed to identify risk factors associated with prolonged recovery times and determine which are most predictive of prolonged recovery times in a head-to-head comparison.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

All concussions occurring between September 2017 and August 2020 at a single National Collegiate Athletic Association Division I institution were reviewed and included in this study. Preinjury modifiers including age, sex, sport, concussion history, and past medical problems were collected from the electronic medical records. Postinjury modifiers analyzed included initial and follow-up Sport Concussion Assessment Tool 5th Edition scores, vestibular evaluation findings, and eye tracking results.

RESULTS

A total of 159 athletes and 187 concussion cases were included. Preinjury factors that were correlated with prolonged RTP times included a history of concussions (P = .015), a history of migraines (P = .013), and whether an athlete participated in an individual sport (P = .009). Postinjury factors correlated with prolonged RTP times included the total number (P = .020) and severity (P = .023) of symptoms as well as abnormal Vestibular Ocular Motor Screening findings (P = .002). Overall, 6 different symptoms (balance problems, difficulty concentrating, light sensitivity, drowsiness, fatigue/low energy, and difficulty remembering) were significantly correlated with prolonged RTP times. The study also found that the number and severity of symptoms were additive in a dose-dependent fashion. On multivariable analysis of all these factors, a history of concussions was found to be the most predictive of prolonged RTP times, while participation in an individual sport had the largest effect on recovery times.

CONCLUSION

Several preinjury and postinjury risk factors were identified as being correlated with prolonged recovery times. Many of these risk factors were also found to be additive in nature. This information provides clinicians with a valuable tool in prognosticating and estimating recovery times for athletes. The study also revealed that athletes participating in individual sports had longer RTP times compared with athletes in team sports, which is a novel finding that requires further research.

Using a Likelihood Heuristic to Summarize Conflicting Literature on Predictors of Clinical Outcome Following Sport-Related Concussion

OBJECTIVE

To introduce a new methodology for summarizing the results from systematic reviews-a likelihood heuristic-to the field of sport-related concussion.

DATA SOURCES

We applied the likelihood heuristic to the results of a systematic review published by Iverson et al (2017), containing 101 studies, on the predictors of worse clinical outcome following sport-related concussion.

STUDY SELECTION

We re-examined 5 individual prognostic factors that are of clinical interest and for which there is conflicting literature (female sex = 44 studies, prior concussion history = 41 studies, loss of consciousness = 31 studies, post-traumatic amnesia = 25 studies, and retrograde amnesia = 10 studies).

DATA EXTRACTION

For each prognostic factor, likelihood ratios were generated using the (1) number of significant and nonsignificant studies, (2) study power, (3) alpha level, and (4) prior probability that the alternative hypothesis was true.

DATA SYNTHESIS

Assuming each study had 80% power and an alpha level of 5%, observing the reported number of conflicting studies for female sex, prior concussion history, and retrograde amnesia is substantially more likely if each prognostic factor is associated with worse clinical outcome following sport-related concussion. For loss of consciousness, the observed number of conflicting studies is more likely if loss of consciousness is not associated with worse clinical outcome following sport-related concussion. A secondary analysis incorporating potentially more realistic study parameters of statistical power (45%) and alpha level (25%) generates weaker likelihood evidence that the observed numbers of studies for each prognostic factor are associated with worse clinical outcome following sport-related concussion than they are not.

CONCLUSIONS

Using a likelihood heuristic with 80% power and 5% alpha level, there is very strong likelihood evidence that female sex, prior concussion history, and retrograde amnesia are associated with worse clinical outcome following sport-related concussion. The strength of likelihood evidence that prognostic factors are associated with worse clinical outcome reduces when statistical power is lower and alpha level is inflated.

Symptom Factors and Neuropsychological Performance in Collegiate Athletes with Chronic Concussion Symptoms

OBJECTIVE

The present study explored the relationship between specific types of postconcussion symptoms and cognitive outcomes in student-athletes with chronic concussion symptoms.

METHOD

Forty student-athletes with chronic concussion symptoms were given a battery of neuropsychological tests and rated themselves on a variety of postconcussion symptoms, which included the following factors derived from prior work: Physical, Sleep, Cognitive, Affective, and Headache. Cognitive outcomes included performance on composites for the memory and attention/executive functioning speed tests, respectively. The following covariates were also explored: Sex, depression symptoms, number of previous concussions, and time since injury.

RESULTS

Headache was the only individual symptom factor that significantly (p < .05) predicted worse attention/executive functioning performance. None of the symptom factors were significantly related to memory performance over and above the variable of time since injury, such that longer time since injury was related to worse memory performance.

CONCLUSION

Comparable to work examining symptom predictors of cognitive outcomes in acutely concussed samples, headache predicted worse attention/executive functioning performance. Additionally, we found that the longer athletes had been symptomatic since injury, the "worse" their memory functioning. Understanding how headache and the length of time an individual is symptomatic are related to cognitive outcomes can help inform treatment and recommendations for athletes with prolonged symptom recovery.

An irritability-based approach to whiplash-associated concussion rehabilitation: a case series

BACKGROUND

An estimated 45% of concussions are reported to be related to motor vehicle collisions (MVC). However, limited research exists involving the treatment of MVC-related concussion, especially when combined with whiplash-associated disorders (WAD). Purpose: The purpose of this case series is to examine the patient response to an irritability-based approach to the physiological, cervical, and vestibulo-ocular trajectories in patients with diagnosed concussion and WAD disorder following an MVC. Case Description: Three patients clinically diagnosed by a neurologist with WAD and concussion following a rear-end MVC were evaluated and treated in an outpatient physical therapy setting. Each individual was progressed through an irritability-based treatment approach based on individual symptom presentation. Outcomes: Following therapy, 2 of 3 patients reported full resolution of subjective symptoms with a negative Vestibular Oculo-motor Screening All patients exceeded their predicted goals based on Focus on Therapeutic Outcomes score.

CONCLUSION

This case series demonstrated successful treatment of all three individuals with concussion and concurrent WAD. Two of three individuals demonstrated full resolution of subjective symptoms and objective impairments at the end of treatment. Further research is warranted into the effectiveness of a multi-factorial approach to address the highly variable symptom profile of individuals with concussion and WAD.

Female Athlete and Sports-Related Concussions

Female athletes are participating in collision sports in greater numbers than previously. The overall incidence of concussion is known to be higher in female athletes than in male athletes participating in similar sports. Evidence suggests anatomic, biomechanical, and biochemical etiologies behind this sex disparity. Future research on female athletes is needed for further guidance on prevention and management of concussion in girls and women.

Bifactor Model of the Sport Concussion Assessment Tool Symptom Checklist: Replication and Invariance Across Time in the CARE Consortium Sample

BACKGROUND

Identifying separate dimensions of concussion symptoms may inform a precision medicine approach to treatment. It was previously reported that a bifactor model identified distinct acute postconcussion symptom dimensions.

PURPOSE

To replicate previous findings of a bifactor structure of concussion symptoms in the Concussion Assessment Research and Education (CARE) Consortium sample, examine measurement invariance from pre- to postinjury, and evaluate whether factors are associated with other clinical and biomarker measures.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

Collegiate athletes were prospectively evaluated using the Sport Concussion Assessment Tool-3 (SCAT-3) during preseason (N = 31,557); 2789 were followed at <6 hours and 24 to 48 hours after concussion. Item-level SCAT-3 ratings were analyzed using exploratory and confirmatory factor analyses. Bifactor and higher-order models were compared for their fit and interpretability. Measurement invariance tested the stability of the identified factor structure across time. The association between factors and criterion measures (clinical and blood-based markers of concussion severity, symptom duration) was evaluated.

RESULTS

The optimal structure for each time point was a 7-factor bifactor model: a General factor, on which all items loaded, and 6 specific factors-Vestibulo-ocular, Headache, Sensory, Fatigue, Cognitive, and Emotional. The model manifested strict invariance across the 2 postinjury time points but only configural invariance from baseline to postinjury. From <6 to 24-48 hours, some dimensions increased in severity (Sensory, Fatigue, Emotional), while others decreased (General, Headache, Vestibulo-ocular). The factors correlated with differing clinical and biomarker criterion measures and showed differing patterns of association with symptom duration at different time points.

CONCLUSION

Bifactor modeling supported the predominant unidimensionality of concussion symptoms while revealing multidimensional properties, including a large dominant General factor and 6 independent factors: Headache, Vestibulo-ocular, Sensory, Cognitive, Fatigue, and Emotional. Unlike the widely used SCAT-3 symptom severity score, which declines gradually after injury, the bifactor model revealed separable symptom dimensions that have distinct trajectories in the acute postinjury period and different patterns of association with other markers of injury severity and outcome.

CLINICAL RELEVANCE

The SCAT-3 total score remains a valuable, robust index of overall concussion symptom severity, and the specific factors identified may inform management strategies. Because some symptom dimensions continue to worsen in the first 24 to 48 hours after injury (ie, Sensory, Fatigue, Emotional), routine follow-up in this time frame may be valuable to ensure that symptoms are managed effectively.

Effects of Exercise on Sport Concussion Assessment Tool-Third Edition Performance in Women

OBJECTIVE

The purpose of this study was to examine the influence of a brief exercise protocol on Sport Concussion Assessment Tool-Third Edition (SCAT3) performance in amateur women athletes.

DESIGN

Cross-over repeated-measures design.

SETTING

Off-season, uninjured community amateur athletes.

PARTICIPANTS

We examined 87 amateur women athlete volunteers (age = 29.9, SD = 6.9 years).

INDEPENDENT VARIABLES

Participants were assessed using the SCAT3 under 2 conditions: at rest and after a 5-minute physical exertion protocol, completed in a counterbalanced order.

MAIN OUTCOME MEASURES

Participants' performance on the various components of the SCAT3 under the 2 conditions: at rest and after a 5-minute physical exertion protocol.

RESULTS

No significant differences were detected between at-rest and postexercise conditions for the balance, orientation, or cognitive components of the SCAT3. There were no significant differences in the proportion of participants who endorsed specific symptoms at rest compared with the postexercise condition (P > 0.05). However, women athletes who rated their exertion after exercise as "hard" or greater (Borg scale rating 13-20) reported significantly greater blurred vision (M = 0.25, SD = 0.62 vs M = 0.00, SD = 0.00; P = 0.006) and fatigue/low energy (M = 1.38, SD = 1.17 vs M = 0.66, SD = 0.91; P = 0.002) symptoms after exercise than those who rated their exertion as "light" or lower (Borg scale rating 6-12).

CONCLUSIONS

In this study of women athletes, a brief bout of exercise did not seem to adversely affect SCAT3 performance and had only small effects on self-reported symptoms. There were differences in symptom reporting, however, in the subgroup of women who rated their exertion levels as "hard" or greater; they reported more blurred vision and fatigue/low energy.

Concussion-Recovery Trajectories Among Tactical Athletes: Results From the CARE Consortium

CONTEXT

Assessments of the duration of concussion recovery have primarily been limited to sport-related concussions and male contact sports. Furthermore, whereas durations of symptoms and return-to-activity (RTA) protocols encompass total recovery, the trajectory of each duration has not been examined separately.

OBJECTIVE

To identify individual (eg, demographics, medical history), initial concussion injury (eg, symptoms), and external (eg, site) factors associated with symptom duration and RTA-protocol duration after concussion.

DESIGN

Cohort study.

SETTING

Three US military service academies.

PATIENTS OR OTHER PARTICIPANTS

A total of 10 604 cadets at participating US military service academies enrolled in the study and completed a baseline evaluation and up to 5 postinjury evaluations. A total of 726 cadets (451 men, 275 women) sustained concussions during the study period.

MAIN OUTCOME MEASURE(S)

Number of days from injury (1) until the participant became asymptomatic and (2) to complete the RTA protocol.

RESULTS

Varsity athlete cadets took less time than nonvarsity cadets to become asymptomatic (hazard ratio [HR] = 1.75, 95% confidence interval = 1.38, 2.23). Cadets who reported less symptom severity on the Sport Concussion Assessment Tool, third edition (SCAT3), within 48 hours of concussion had 1.45 to 3.77 times shorter symptom-recovery durations than those with more symptom severity. Similar to symptom duration, varsity status was associated with a shorter RTA-protocol duration (HR = 1.74, 95% confidence interval = 1.34, 2.25), and less symptom severity on the SCAT3 was associated with a shorter RTA-protocol duration (HR range = 1.31 to 1.47). The academy that the cadet attended was associated with the RTA-protocol duration (P < .05).

CONCLUSIONS

The initial total number of symptoms reported and varsity athlete status were strongly associated with symptom and RTA-protocol durations. These findings suggested that external (varsity status and academy) and injury (symptom burden) factors influenced the time until RTA.

Factors Associated With Self-Reported Concussion History in Middle School Athletes

OBJECTIVE

Identifying personal characteristics associated with sustaining a concussion is of great interest, yet only a few have examined this in children. The purpose of this study was to examine the association between sex, neurodevelopmental disorders, health history, and lifetime history of self-reported concussion in 12- and 13-year-old athletes.

DESIGN

Cross-sectional study.

SETTING

Middle schools.

PARTICIPANTS

Participants were 1744 twelve- and thirteen-year-old student athletes who completed preseason Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) testing, including a self-report questionnaire about previous concussions, developmental diagnoses, and previous medical treatment.

INDEPENDENT VARIABLES

Age, sex, attention-deficit/hyperactivity disorder (ADHD), learning disabilities (LDs), and previous treatment for migraine.

MAIN OUTCOME MEASURES

Self-reported history of concussion.

RESULTS

A minority of athletes (13.7%) reported previous concussions (1 concussion, n = 181; 2 concussions, n = 41; and 3+ concussions, n = 17). A small proportion reported a history of ADHD (4.4%), LD (2.8%) or migraine treatment (4.0%). Higher rates of self-reported previous concussions were associated with male sex [16.9% vs 9.1%; χ(1) = 21.47, P < 0.001] and previous migraine treatment [31.9% vs 13.0%; χ(1) = 20.08, P < 0.001]. There were no differences in self-reported concussion history between 12- and 13-year olds (P = 0.18) and those with/without ADHD (P = 0.41) or LDs (P = 0.06). The overall logistic regression model was statistically significant [χ(5) = 42.01, P < 0.001] but explained only 4.3% of the variance. Previous treatment for migraine [P < 0.001, Exp(B) = 3.30] and male sex [P < 0.001, Exp(B) = 2.06] were independently associated with a self-reported concussion history, whereas age, LD, and ADHD were not (P's > 0.05).

CONCLUSIONS

Male sex and previous migraine treatment were associated with higher rates of self-reported previous concussions in both independent and multivariate models in middle school athletes, whereas age, ADHD, and LDs were not.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Is There an Optimal Time to Initiate an Active Rehabilitation Protocol for Concussion Management in Children? A Case Series

OBJECTIVE

To estimate the time frame during which initiating an active rehabilitation intervention (aerobic exercise, balance, and sport specific skills) after concussion contributed to improvement in symptoms at follow-up in children and adolescents who are slow to recover (symptoms persisting beyond 2 weeks) from concussion.

SETTING

Concussion clinic at a tertiary care pediatric teaching hospital.

PARTICIPANTS

A total of 677 children and adolescents with concussion aged 7 to 18 years.

DESIGN

Case series of participants starting active rehabilitation less than 2, 2, 3, 4, 5, or 6 or more weeks postconcussion.

MAIN MEASURE

Symptom severity measured by the 22-item Post-Concussion Scale (PCS)-revised.

RESULTS

All patients experienced significant improvement of symptoms while participating in active rehabilitation, irrespective of the start time postonset. Patients initiating active rehabilitation at 2 (P < .001) or 3 (P = .039) weeks postinjury demonstrated lower symptom severity at follow-up than those starting at 6 weeks or later. Patients starting at 2 weeks had lower symptom severity than patients starting less than 2 (P = .02), 4 (P = .20), or 5 weeks postinjury (P = .04). Lastly, patients starting less than 2 and 6 weeks or more postinjury yielded equivalent outcomes.

CONCLUSIONS

The findings support the use of active rehabilitation in children and adolescents who are slow to recover from concussion. Participants starting active rehabilitation less than 2 weeks and up to 6 or more weeks postconcussion demonstrated significant symptom improvements, but improvement was observed in all groups, regardless of the time to start active rehabilitation.

Preinjury Migraine History as a Risk Factor for Prolonged Return to School and Sports following Concussion

Having a preexisting migraine disorder might be a risk factor for a prolonged recovery following a sport-related concussion. We examined whether having a migraine history was associated with a prolonged return to academics and athletics following a concussion. High school and collegiate athletes (n = 1265; 42% female) who sustained a sport-related concussion were monitored by athletic trainers using a web-based surveillance system that collects information about concussion recovery. Nonparametric Kolmogorov-Smirnov tests (KS) were used to compare days to return to academics/athletics across groups due to non-normally distributed outcome variables and unequal distributions of scores between groups. Chi-squared tests were used to examine the proportion of players who had not returned to academics/athletics at 7, 14, and 21 days post-injury stratified by self-reported migraine history. There were 117 athletes (9.2%) who reported a preinjury migraine history. Athletes with a history of migraine took a median of 6 days to return to academics (mean [M] = 10.6, standard deviation [SD] = 14.2) and 15.5 days to return to athletics (M = 23.8, SD = 30.8), while those with no migraine history took a median of 5 days to return to academics (M = 7.5, SD = 10.9) and 14 days to return to athletics (M = 19.4, SD = 19.4). There were no statistically significant differences in days to return to school or athletics between the groups (KS p > 0.05). However, a lower percentage of athletes with a history of migraine had returned to school after 7 days (57% vs. 68%, χ2 = 5.53, p = 0.02), 14 days (75% vs. 88%, χ2 = 14.21, p < 0.001), and 21 days post-injury (89% vs. 94%, χ2 = 4.90, p = 0.03). Stratifying the analyses by sex showed that this effect was significant in girls and women with preexisting migraines, but not boys and men with preexisting migraines. There were no group differences in recovery rates when examining return to athletics. Athletes with a preinjury migraine history may be at an elevated risk for a protracted return to school after concussion, especially girls and women.

Imaging Post-Traumatic Headache

PURPOSE OF REVIEW

Headache is a frequent and debilitating symptom after mild traumatic brain injury, yet little is known about its pathophysiology and most effective treatments. The goal of this review is to summarize findings from imaging studies used during the clinical evaluation and research investigation of post-traumatic headache (PTH).

RECENT FINDINGS

There are no published recommendations or guidelines for when to acquire imaging studies of the head or neck in patients with PTH. Clinical acumen is required to determine if imaging is needed to assess for a secondary cause of headache which may have been precipitated or unmasked by the trauma. Several guidelines for when to image the patient with mild traumatic brain injury (mTBI) in the emergency setting consider headache among the deciding factors. In the research arena, imaging techniques including proton spectroscopy magnetic resonance imaging, diffusion tensor imaging, magnetic resonance morphometry, and functional neck x-rays have been employed with the goal of identifying diagnostic and prognostic factors for PTH and to help understand its underlying pathophysiologic mechanisms. Results indicate that changes in regional cortical thickness and damage to specific white matter tracts warrant further research. Future research should interrogate whether these imaging findings contribute to the classification and prognosis of PTH. Current research provides evidence that imaging findings associated with PTH may be distinct from those attributable to mTBI. A variety of imaging techniques have potential to further our understanding of the pathophysiologic processes underlying PTH as well as to provide diagnostic and prognostic indicators. However, considerable work must be undertaken for this to be realized.

Sex-specific Outcomes and Predictors of Concussion Recovery

INTRODUCTION

Sports-related concussion (SRC) is a substantial concern in collegiate athletics. Some studies of SRC that make comparisons by sex are limited by sample size, follow-up duration, or referral bias. Sex-specific predictors of occurrence and recovery are uncertain.

METHODS

A 15-year retrospective cohort study identified 1,200 Columbia University varsity athletes (822 male [68.5%], 378 female [31.5%]) at risk of collegiate SRC.

RESULTS

A total of 228 athletes experienced at least one collegiate concussion, including 88 female athletes (23.3% of female athletes) and 140 male athletes (17.0% of male athletes) (P = 0.01); follow-up data were available on 97.8% of these athletes. Postconcussion symptoms were similar by sex, with the exception of sleep disturbance (29.3% of male athletes versus 42.0% of female athletes; P = 0.048) and memory impairment (43.6% of male athletes versus 30.7% of female athletes; P = 0.052), although the latter difference was not statistically significant. Risk factors for collegiate concussion included female sex (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1 to 2.0) or precollegiate concussion (OR, 2.9; 95% CI, 2.2 to 3.9). Prolonged recovery was predicted by the presence of eight or more postconcussion symptoms for all athletes (OR, 3.77; 95% CI, 1.68 to 8.46) and for female athletes only (OR, 8.24; 95% CI, 1.58 to 43.0); this finding was not statistically significant for male athletes.

DISCUSSION

Female athletes were more likely than male athletes to experience concussion. Increasing numbers of prior concussions predicted recurrence. Although most postconcussion symptoms were highly intercorrelated, the total number of symptoms predicted a prolonged recovery period.

CONCLUSION

This study confirms sex-based differences in SRCs. Longitudinal studies of collegiate cohorts should attempt to limit follow-up bias and offer opportunities to clarify determinants of SRC.

Evidence of Concussion Signs in National Rugby League Match Play: a Video Review and Validation Study

BACKGROUND

Many professional sports have introduced sideline video review to help recognise concussions. The reliability and validity of identifying clinical and observable signs of concussion using video analysis has not been extensively explored. This study examined the reliability and validity of clinical signs of concussion using video analysis in the National Rugby League (NRL).

METHODS

All 201 professional NRL matches from the 2014 season were reviewed to document six signs of possible concussion (unresponsiveness, slow to get up, clutching/shaking head, gait ataxia, vacant stare, and seizure).

RESULTS

A total of 127,062 tackles were reviewed. Getting up slowly was the most common observable sign (2240 times in the season, 1.8% of all tackles) but only 223 times where it appeared to be a possible concussion (0.2% of all tackles and 10.0% of the times it occurred). Additionally, clutching/shaking the head occurred 361 times (on 212 occasions this sign appeared to be due to a possible concussion), gait ataxia was observed 102 times, a vacant stare was noted 98 times, unresponsiveness 52 times, and a possible seizure 4 times. On 383 occasions, one or more of the observable signs were identified and deemed associated with a possible concussion. There were 175 incidences in which a player appeared to demonstrate two or more concussion signs, and 54 incidences where a player appeared to demonstrate three or more concussion signs. A total of 60 diagnosed concussions occurred, and the concussion interchange rule was activated 167 times. Intra-rater reliability (κ = 0.65-1.00) was moderate to perfect for all six video signs; however, the inter-rater reliability was not as strong (κ = 0.22-0.76). Most of the signs had relatively low sensitivity (0.18-0.75), but high specificity (0.85-1.00).

CONCLUSIONS

Using video replay, observable signs of concussion appear to be sensitive to concussion diagnoses when reviewing known injuries among professional rugby league players. When reviewing an entire season, however, certain signs occur very commonly and did not identify concussion. Thus, the implementation of video review in the NRL is challenging, but can provide a useful addition to sideline concussion identification and removal from play decisions.

Observational Review and Analysis of Concussion: a Method for Conducting a Standardized Video Analysis of Concussion in Rugby League

Background

Several professional contact and collision sports have recently introduced the use of sideline video review for club medical staff to help identify and manage concussions. As such, reviewing video footage on the sideline has become increasingly relied upon to assist with improving the identification of possible injury. However, as yet, a standardized method for reviewing such video footage in rugby league has not been published. The aim of this study is to evaluate whether independent raters reliably agreed on the injury characterization when using a standardized observational instrument to record video footage of National Rugby League (NRL) concussions.

Methods

Video footage of 25 concussions were randomly selected from a pool of 80 medically diagnosed concussions from the 2013–2014 NRL seasons. Four raters (two naïve and two expert) independently viewed video footage of 25 NRL concussions and completed the Observational Review and Analysis of Concussion form for the purpose of this inter-rater reliability study. The inter-rater reliability was calculated using Cohen’s kappa (κ) and intra-class correlation (ICC) statistics. The two naïve raters and the two expert raters were compared with one another separately.

Results

A considerable number of components for the naïve and expert raters had almost perfect agreement (κ or ICC value ≥ 0.9), 9 of 22 (41%) components for naïve raters and 21 of 22 (95%) components for expert raters. For the concussion signs, however, the majority of the rating agreement was moderate (κ value 0.6–0.79); both the naïve and expert raters had 4 of 6 (67%) concussion signs with moderate agreement. The most difficult concussion sign to achieve agreement on was blank or vacant stare, which had weak (κ value 0.4–0.59) agreement for both naïve and expert raters.

Conclusions

There appears to be value in expert raters, but less value for naive raters, in using the new Observational Review and Analysis of Concussion (ORAC) Form. The ORAC Form has high inter-rater agreement for most data elements, and it can be used by expert raters evaluating video footage of possible concussion in the NRL.

Predictors of clinical recovery from concussion: a systematic review

OBJECTIVE

A systematic review of factors that might be associated with, or influence, clinical recovery from sport-related concussion. Clinical recovery was defined functionally as a return to normal activities, including school and sports, following injury.

DESIGN

Systematic review.

DATA SOURCES

PubMed, PsycINFO, MEDLINE, CINAHL, Cochrane Library, EMBASE, SPORTDiscus, Scopus and Web of Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies published by June of 2016 that addressed clinical recovery from concussion.

RESULTS

A total of 7617 articles were identified using the search strategy, and 101 articles were included. There are major methodological differences across the studies. Many different clinical outcomes were measured, such as symptoms, cognition, balance, return to school and return to sports, although symptom outcomes were the most frequently measured. The most consistent predictor of slower recovery from concussion is the severity of a person's acute and subacute symptoms. The development of subacute problems with headaches or depression is likely a risk factor for persistent symptoms lasting greater than a month. Those with a preinjury history of mental health problems appear to be at greater risk for having persistent symptoms. Those with attention deficit hyperactivity disorder (ADHD) or learning disabilities do not appear to be at substantially greater risk. There is some evidence that the teenage years, particularly high school, might be the most vulnerable time period for having persistent symptoms-with greater risk for girls than boys.

CONCLUSION

The literature on clinical recovery from sport-related concussion has grown dramatically, is mostly mixed, but some factors have emerged as being related to outcome.

What is the difference in concussion management in children as compared with adults? A systematic review

AIM

To evaluate the evidence regarding the management of sport-related concussion (SRC) in children and adolescents. The eight subquestions included the effects of age on symptoms and outcome, normal and prolonged duration, the role of computerised neuropsychological tests (CNTs), the role of rest, and strategies for return to school and return to sport (RTSp).

DESIGN

Systematic review.

DATA SOURCES

MEDLINE (OVID), Embase (OVID) and PsycInfo (OVID).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they were original research on SRC in children aged 5 years to 18 years, and excluded if they were review articles, or did not focus on childhood SRC.

RESULTS

A total of 5853 articles were identified, and 134 articles met the inclusion criteria. Some articles were common to multiple subquestions. Very few studies examined SRC in young children, aged 5-12 years.

SUMMARY/CONCLUSIONS

This systematic review recommends that in children: child and adolescent age-specific paradigms should be applied; child-validated symptom rating scales should be used; the widespread routine use of baseline CNT is not recommended; the expected duration of symptoms associated with SRC is less than 4 weeks; prolonged recovery be defined as symptomatic for greater than 4 weeks; a brief period of cognitive and physical rest should be followed with gradual symptom-limited physical and cognitive activity; all schools be encouraged to have a concussion policy and should offer appropriate academic accommodations and support to students recovering from SRC; and children and adolescents should not RTSp until they have successfully returned to school, however early introduction of symptom-limited physical activity is appropriate.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2016:CRD42016039184.

Evaluation of Nintendo Wii Balance Board as a Tool for Measuring Postural Stability After Sport-Related Concussion

CONTEXT

Recent changes to postconcussion guidelines indicate that postural-stability assessment may augment traditional neurocognitive testing when making return-to-participation decisions. The Balance Error Scoring System (BESS) has been proposed as 1 measure of balance assessment. A new, freely available software program to accompany the Nintendo Wii Balance Board (WBB) system has recently been developed but has not been tested in concussed patients.

OBJECTIVE

To evaluate the feasibility of using the WBB to assess postural stability across 3 time points (baseline and postconcussion days 3 and 7) and to assess concurrent and convergent validity of the WBB with other traditional measures (BESS and Immediate Post-Concussion Assessment and Cognitive Test [ImPACT] battery) of assessing concussion recovery.

DESIGN

Cohort study.

SETTING

Athletic training room and collegiate sports arena.

PATIENTS OR OTHER PARTICIPANTS

We collected preseason baseline data from 403 National Collegiate Athletic Association Division I and III student-athletes participating in contact sports and studied 19 participants (age = 19.2 ± 1.2 years, height = 177.7 ± 8.0 cm, mass = 75.3 ± 16.6 kg, time from baseline to day 3 postconcussion = 27.1 ± 36.6 weeks) who sustained concussions.

MAIN OUTCOME MEASURE(S)

We assessed balance using single-legged and double-legged stances for both the BESS and WBB, focusing on the double-legged, eyes-closed stance for the WBB, and used ImPACT to assess neurocognition at 3 time points. Descriptive statistics were used to characterize the sample. Mean differences and Spearman rank correlation coefficients were used to determine differences within and between metrics over the 3 time points. Individual-level changes over time were also assessed graphically.

RESULTS

The WBB demonstrated mean changes between baseline and day 3 postconcussion and between days 3 and 7 postconcussion. It was correlated with the BESS and ImPACT for several measures and identified 2 cases of abnormal balance postconcussion that would not have been identified via the BESS.

CONCLUSIONS

When accompanied by the appropriate analytic software, the WBB may be an alternative for assessing postural stability in concussed student-athletes and may provide additional information to that obtained via the BESS and ImPACT. However, verification among independent samples is required.

Statements of Agreement From the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015

BACKGROUND

Conventional management for concussion involves prescribed rest and progressive return to activity. Recent evidence challenges this notion and suggests that active approaches may be effective for some patients. Previous concussion consensus statements provide limited guidance regarding active treatment.

OBJECTIVE

To describe the current landscape of treatment for concussion and to provide summary agreements related to treatment to assist clinicians in the treatment of concussion.

METHODS

On October 14 to 16, 2015, the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion meeting was convened in Pittsburgh, Pennsylvania. Thirty-seven concussion experts from neuropsychology, neurology, neurosurgery, sports medicine, physical medicine and rehabilitation, physical therapy, athletic training, and research and 12 individuals representing sport, military, and public health organizations attended the meeting. The 37 experts indicated their agreement on a series of statements using an audience response system clicker device.

RESULTS

A total of 16 statements of agreement were supported covering (1) Summary of the Current Approach to Treating Concussion, (2) Heterogeneity and Evolving Clinical Profiles of Concussion, (3) TEAM Approach to Concussion Treatment: Specific Strategies, and (4) Future Directions: A Call to Research. Support (ie, response of agree or somewhat agree) for the statements ranged from to 97% to 100%.

CONCLUSION

Concussions are characterized by diverse symptoms and impairments and evolving clinical profiles; recovery varies on the basis of modifying factors, injury severity, and treatments. Active and targeted treatments may enhance recovery after concussion. Research is needed on concussion clinical profiles, biomarkers, and the effectiveness and timing of treatments.

ABBREVIATIONS

ARS, audience response systemCDC, Centers for Disease Control and PreventionDoD, Department of DefensemTBI, mild traumatic brain injuryNCAA, National Collegiate Athletic AssociationNFL, National Football LeagueNIH, National Institutes of HealthRCT, randomized controlled trialRTP, return to playSRC, sport- and recreation-related concussionTBI, traumatic brain injuryTEAM, Targeted Evaluation and Active Management.

Sex Differences in Time to Return-to-Play Progression After Sport-Related Concussion

Background:

Recently, female sports participation has increased, and there is a tendency for women to experience more symptoms and variable presentation after sport-related concussion (SRC). The purpose of this study was to determine whether sex differences exist in time to begin a return-to-play (RTP) progression after an initial SRC.

Hypothesis:

After initial SRC, female athletes (11-20 years old) would take longer to begin an RTP progression compared with age-matched male athletes.

Study Design:

Retrospective cohort study.

Level of Evidence:

Level 3.

Methods:

A total of 579 participants (365 males [mean age, 15.0 ± 1.7 years], 214 females [mean age, 15.2 ± 1.5 years]), including middle school, high school, and collegiate athletes who participated in various sports and experienced an initial SRC were included and underwent retrospective chart review. The following information was collected: sex, age at injury, sport, history of prior concussion, date of injury, and date of initiation of RTP progression. Participants with a history of more than 1 concussion or injury sustained from non–sport-related activity were excluded.

Results:

Despite American football having the greatest percentage (49.2%) of sport participation, female athletes took significantly longer to start an RTP progression after an initial SRC (29.1 ± 26.3 days) compared with age-matched male athletes (22.7 ± 18.3 days; P = 0.002).

Conclusion:

On average, female athletes took approximately 6 days longer to begin an RTP progression compared with age-matched male athletes. This suggests that sex differences exist between athletes, aged 11 to 20 years, with regard to initiation of an RTP progression after SRC.

Clinical Relevance:

Female athletes may take longer to recover after an SRC, and therefore, may take longer to return to sport. Sex should be considered as part of the clinical decision-making process when determining plan of care for this population.

Examining Recovery Trajectories After Sport-Related Concussion With a Multimodal Clinical Assessment Approach

BACKGROUND

Previous research estimates that the majority of athletes with sport-related concussion (SRC) will recover between 7 and 10 days after injury. This short temporal window of recovery is based predominately on symptom resolution and cognitive improvement and does not accurately reflect recent advances in the clinical assessment model.

OBJECTIVE

To characterize SRC recovery at 1-week postinjury time intervals on symptom, neurocognitive, and vestibular-oculomotor outcomes and to examine sex differences in SRC recovery time.

METHODS

A prospective, repeated-measures design was used to examine the temporal resolution of neurocognitive, symptom, and vestibular-oculomotor impairment in 66 subjects (age, 16.5 ± 1.9 years; range, 14-23 years; 64% male) with SRC.

RESULTS

Recovery time across all outcomes was between 21 and 28 days after SRC for most athletes. Symptoms demonstrated the greatest improvement in the first 2 weeks, although neurocognitive impairment lingered across various domains up to 28 days after SRC. Vestibular-oculomotor decrements also resolved between 1 and 3 weeks after injury. There were no sex differences in neurocognitive recovery. Male subjects were more likely to be asymptomatic by the fourth week and reported less vestibular-oculomotor impairment than female subjects at weeks 1 and 2.

CONCLUSION

When the recommended "comprehensive" approach is used for concussion assessment, recovery time for SRC is approximately 3 to 4 weeks, which is longer than the commonly reported 7 to 14 days. Sports medicine clinicians should use a variety of complementing assessment tools to capture the heterogeneity of SRC.

The Prevalence of Headache Among Athletic University Students

Background:

Headache is certainly one of the most common medical complaints of general population and one of the important causes of consumption of drugs. Despite its high overall prevalence, the epidemiology of exertional headache is not clear enough.

Objectives:

To determine the prevalence of headache in athletic and non-athletic university students and also estimating its variation between different sports fields including concussion prone sports.

Materials and Methods:

This cross-sectional study comprised 739 subjects (367 athletes and 372 non-athletes). The present study was carried out on athletic and non-athletic university students aging between 18 to 28 years. An athlete was defined as a person who had at least one year of experience in sports including football, volleyball, basketball, wrestling, boxing, martial arts, track and field, chess, handball and swimming for three sessions a week each lasting at least 2 hours. The random selection of these participants was done by an independent statistical consultant. A questionnaire was used for data collection which was then analyzed by statistical methods.

Results:

Our study comprised 739 subjects (367 athletes and 372 non-athletes). Among athletic university students, 152 (41.2%) participants complained of headache. Such a complaint was present in 217 (58.3%) non-athletic university students. This lower prevalence of headache in athletes was statistically significant (P value < 0.001). Among ten different sports fields, the prevalence of headache among wrestlers was significantly higher than others (P value < 0.001).

Conclusions:

The prevalence of headache is seemingly lower in athletic university students than non-athletic ones. In addition, among athletes, those who are participating in concussion prone sports especially wrestling experience headache more than athletes of other fields.

Pediatric Posttraumatic Headache: A Review

Head injuries are common in pediatrics, and headaches are the most common complaint following mild head trauma. Although moderate and severe traumatic brain injuries occur less frequently, headaches can complicate recovery. There is currently an intense spotlight on concussion and there has been a corresponding increase in the number of children seeking care for headache after mild traumatic brain injury or concussion. Understanding the natural history of, and recognition of factors that are associated with posttraumatic headache will help providers and families to limit disability and may prompt earlier intervention to address disabling headaches. While there are few studies on the treatment of posttraumatic headache, proper evaluation and management of posttraumatic headaches is essential to prevent further injury and to promote recovery. In this article, we will review the current definitions and epidemiology of pediatric posttraumatic headache and discuss current recommendations for the evaluation and management of this syndrome in children and adolescents.

Relationship of Attention Deficit Hyperactivity Disorder and Postconcussion Recovery in Youth Athletes

OBJECTIVE

To investigate whether attention deficit hyperactivity disorder (ADHD) influences postconcussion recovery, as measured by computerized neurocognitive testing.

DESIGN

This is a retrospective case control study.

SETTING

Computer laboratories across 10 high schools in the greater Atlanta, Georgia area.

PARTICIPANTS

Immediate postconcussion assessment and cognitive testing (ImPACT) scores of 70 athletes with a self-reported diagnosis of ADHD and who sustained a sport-related concussion were compared with a randomly selected age-matched control group. Immediate postconcussion assessment and cognitive testing scores over a 5-year interval were reviewed for inclusion.

MAIN OUTCOME MEASURES

Postconcussion recovery was defined as a return to equivalent baseline neurocognitive score on the ImPACT battery, and a concussion symptom score of ≤7.

RESULTS

Athletes with ADHD had on average a longer time to recovery when compared with the control group (16.5 days compared with 13.5 days), although not statistically significant. The number of previous concussions did not have any effect on the rate of recovery in the ADHD or the control group. In addition, baseline neurocognitive testing did not statistically differ between the 2 groups, except in verbal memory.

CONCLUSIONS

Although not statistically significant, youth athletes with ADHD took on average 3 days longer to return to baseline neurocognitive testing compared with a control group without ADHD.

CLINICAL RELEVANCE

Youth athletes with ADHD may have a marginally prolonged recovery as indexed by neurocognitive testing and should be considered when prognosticating time to recovery in this subset of student athletes.

Characterization of acute stress reaction following an IED blast-related mild traumatic brain injury

PRIMARY OBJECTIVE

To characterize an acute stress reaction (ASR) following an improvised explosive device (IED) blast-related mild traumatic brain injury (mTBI).

RESEARCH DESIGN

Participants were male, US military personnel treated in Afghanistan within 4 days following an IED-related mTBI event (n = 239).

METHODS AND PROCEDURES

Demographics, diagnosis of ASR, injury history and self-reported mTBIs, blast exposures and psychological health histories were recorded.

MAIN OUTCOMES AND RESULTS

In total, 12.5% of patients met ASR criteria. Patients with ASR were significantly younger and junior in rank (p < 0.05). Patients with ASR were more likely to experience the IED-blast while dismounted, report a loss of consciousness (LOC) and higher pain levels (p < 0.05). Adjusting for age and rank, multivariate logistic regression showed an association between mTBI history and ASR (AOR = 1.405; 95% CI = 1.105-1.786, p < 0.01). Adjusting for mechanism of injury (dismounted vs. mounted), LOC and pain, multivariate logistic regression showed an association between mTBI history and ASR (AOR = 1.453; 95% CI = 1.132-1.864, p < 0.01). Prior blast exposure and past psychological health issues were not associated with ASR.

CONCLUSIONS

A history of multiple mTBIs is associated with increased risk of ASR. Future research is warranted.

Return to rugby after brain concussion: a prospective study in 35 high level rugby players

Background:

Although guidelines based on expert opinions have been developed for the immediate management and return to play of athletes after a concussion, data are lacking on this issue.

Objectives:

Evaluate a standardized management of brain concussion among rugby players to prevent the recurrence.

Patients and Methods:

A prospective study was performed from September 2009 to June 2012. All rugby players who had a concussion when playing rugby were included. Patients were managed by a specialized hospital team with a specific protocol developed in collaboration with the medical staff of the rugby clubs included in the study. The series included 35 rugby players, with 23 professionals and 12 high-level players, 30 men and 5 women, mean age 23.1 ± 5.5 years old. The median number of previous concussions was 2 (0-30) episodes. According to the Cantu concussion severity classification, 3 athletes were grade 1, 12 were grade 2 and 20 were grade 3. None of the injured athletes was lost to follow-up. The primary endpoint was the occurrence of a new concussion within 3 months after the first in patients who returned to rugby.

Results:

Thirty-three patients returned to rugby after a mean 22.1 ± 10 days. The recurrence rate within 3 months was 2/33 (6.1%). The median delay before returning to rugby was 21 (7-45) days. Factors associated with a delayed return to play were young age, initial loss of consciousness, severity Cantu grade 3 and post-concussive syndrome of more than 5 days. Analysis of two failures showed that the initial injury was grade 3 and that both were professional athletes and had a history of concussion.

Conclusions:

This prospective study validated the study protocol for the management of concussion in rugby players.

On-field performance of national football league players after return from concussion

BACKGROUND

There are few data examining the short-term effects of concussions on player performance upon return to play. This study examined changes in on-field performance and the influence of epidemiologic factors on performance and return to play.

HYPOTHESIS

On-field performance is different in players who return within 7 days after concussion compared with players who miss at least 1 game.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Players in the National Football League who were active during the 2008 to 2012 seasons were considered for inclusion. Weekly injury reports identified concussed players. All players played in at least 4 games before and after the game of injury (sentinel game) within the year of injury (sentinel year). Players who had missed games secondary to another injury or had sustained a second concussion within the sentinel year were excluded. The players' league profiles were used to determine age, position, body mass index, career experience, and games missed. ProFootballFocus performance scores determined player ratings. Statistical analysis used 2-sided t tests and both univariate and multivariate logistic regression models.

RESULTS

There were a total of 131 concussions in the 124 players who qualified for this study; 55% of these players missed no games. Defensive secondary, wide receiver, and offensive line were the most commonly affected positions. Players who missed at least 1 game were younger and less experienced. Preinjury ProFootballFocus performance scores were similar to postinjury performance in players without games missed (0.16 vs 0.33; P = .129) and players who missed at least 1 game (-0.06 vs 0.10; P = .219). Age, body mass index, experience, and previous concussion did not correlate with changes in postinjury scores (P > .05). Older, more experienced players and players with late-season concussions were more likely to return to play without missing games (P < .05). The odds of returning within 7 days increased by 18% for each career year and by 40% for each game before the sentinel game within the sentinel year; these same odds decreased by 85% after introduction of newer treatment guidelines in 2009.

CONCLUSION

No difference in player performance after concussion was found whether the player did or did not miss games before return. Return without missing games may be associated with experience and timing of injury within a season and less likely after newer guidelines.

Traumatic brain injury: considering collaborative strategies for early detection and interventional research

Mild traumatic brain injury (mTBI) is a graded sequence of injuries, which is clinically defined based on subjective symptoms observed by clinicians and/or those reported by patients. Much of the focus on research and prevention of mTBI has been on professional or collegiate-level athletes, despite children and young teenagers being at greatest risk for mTBI. Further, continued involvement in sports across the lifespan, increases the likelihood that youth athletes may sustain repetitive brain trauma, which may result in permanent neurological and psychological deficits. Thus, there is a clear need for a population health initiative and research efforts that focus on the juvenile athlete population; in order to fill in the gap in knowledge about the long-term physiological effects of injury and social outcomes, as well as devise strategies that can help in early detection, prevention and treatment; and in the setting of evidence-based Return-To-Play guidelines.