Concussion In Athletes Research Articles

Athlete concussion history recall is underestimated: a validation study of self-reported concussion history among current professional rugby union players

ABSTRACT Objective: To assess the concurrent validity and test re-test reliability of the Michigan Traumatic Brain Injury Identification Method (MTBIIM). The psychometric properties of this concussion index were investigated by comparing the agreement between player self-reported diagnosed concussions and medical record diagnosed concussions among professional rugby union players. Study Design: Cross-sectional study i) validation and ii) test re-test reliability. Methods: The MTBIIM was administered via a structured interview to obtain the number and nature of player self-reported concussion histories from players, while contracted to the host club. Self-reported concussion history information was compared to medically recorded data captured between 2008 and 2017. A mixed-effects logistic regression model explored predictors of player self-report accuracy. Results: Data from 62 players (25.39[4.36] years) included 99 unique rugby related concussions. Medically documented concussions (n = 92) per player (1.48 [1.96]) were 30% more than the mean number of self-reported diagnosed (n = 63) concussions per player (1.02 [1.21] events). Overall, self-reported diagnosed concussions and medical record diagnosed concussion histories had a ‘fair’ level of agreement (k=0.274; SE [0.076]), p=.001). Self-reported lifetime concussion history was signicantly negatively correlated with recall of concussions. Conclusions: Initial concurrent validity of the MTBIIM was found to be fair with the average athlete under-reporting the number of clinically diagnosed concussions.

Predicting Risk of Sport-Related Concussion in Collegiate Athletes and Military Cadets: A Machine Learning Approach Using Baseline Data from the CARE Consortium Study.

To develop a predictive model for sport-related concussion in collegiate athletes and military service academy cadets using baseline data collecting during the pre-participation examination. Baseline assessments were performed in 15,682 participants from 21 US academic institutions and military service academies participating in the CARE Consortium Study during the 2015-2016 academic year. Participants were monitored for sport-related concussion during the subsequent season. 176 baseline covariates mapped to 957 binary features were used as input into a support vector machine model with the goal of learning to stratify participants according to their risk for sport-related concussion. Performance was evaluated in terms of area under the receiver operating characteristic curve (AUROC) on a held-out test set. Model inputs significantly associated with either increased or decreased risk were identified. 595 participants (3.79%) sustained a concussion during the study period. The predictive model achieved an AUROC of 0.73 (95% confidence interval 0.70-0.76), with variable performance across sports. Features with significant positive and negative associations with subsequent sport-related concussion were identified. This predictive model using only baseline data identified athletes and cadets who would go on to sustain sport-related concussion with comparable accuracy to many existing concussion assessment tools for identifying concussion. Furthermore, this study provides insight into potential concussion risk and protective factors.

Differences in sport-related concussion for female and male athletes in comparable collegiate sports: a study from the NCAA-DoD Concussion Assessment, Research and Education (CARE) Consortium

ObjectivesTo examine sex differences in sport-related concussion (SRC) across comparable sports.MethodsProspective cohort of collegiate athletes enrolled between 2014 and 2017 in the Concussion Assessment, Research and Education Consortium study.ResultsAmong 1071...

Evaluation of Musculoskeletal Re-Injury Occurrence in Previously Concussed National Football League Athletes.

IntroductionIncreased risk of musculoskeletal (MSK) injury post-concussion has been reported in collegiate athletes, yet it is unknown if professional football athletes are at the same risk of secondary injury. The objective of this study was to determine if the risk of MSK injury in National Football League (NFL) athletes increases after concussion.MethodsNFL injury reports from 2013 to 2017 were collected from public websites. Concussed athletes (n=91) were equally matched to a non-injured control and an athlete with an incident of musculoskeletal (MSK) injury.ResultsFollowing their return to sport, concussed athletes were 2.35 times more likely to have a subsequent MSK injury relative to non-injured controls (95% CI: 2.35 [1.25, 4.44], P = 0.01), but were no more likely than athletes with an incident MSK injury (P = 0.55). Likewise, athletes with an incident MSK injury were no more likely to have a subsequent MSK injury than controls (P = 0.08).DiscussionIncreased odds of MSK injury in the 12-week period following a concussion in professional football athletes warrants future research on the acute effects of concussion and the relationship to MSK injury risk.

Steady-State Visual-Evoked Potentials as a Biomarker for Concussion: A Pilot Study

This study aims to utilize a portable system capable of measuring steady-state visual evoked potentials (SSVEP) to investigate their use as an objective electrophysiologic biomarker for concussion. The most pressing issues in relation to sports related concussion (SRC) involves accurate and timely diagnosis, for a safe return to play criteria. Despite the vast range of tools available to help clinicians assess concussion, most are subjective, non-portable, and therefore non-ideal for unbiased application at the site and time of a suspected injury. This system applied a smartphone housed in a VR-frame delivering a 15-Hz flickering stimulus while a wireless electroencephalography (EEG) headset recorded EEG signals. Sixty-five male amateur rugby athletes (20.9 ± 2.3 years-old) were tested throughout a season and were stratified into healthy, concussed, and recovered groups based on clinical examinations pre- and post-competitive games. Players SSVEP responses was quantified into a signal-to-noise ratio (SNR) and summarized into respective study-groups for comparison of medians with 25th-75th interquartile range. All sixty-five participants completed a baseline evaluation preseason. Twelve participants sustained a diagnosed concussion during the season and were retested within 72 h of injury. Eight concussed players received additional SSVEP testing following a 2-week recovery period. Concussed participants had a significantly lower SNR [2.20 (2.04-2.38)] when compared to their baseline [4.54 (3.79-5.10)]. When clinically recovered, participant SNR [4.82 (4.13-5.18)] was not significantly different to their baseline. Baseline SNR of concussed and non-concussed participants [4.80 (4.07-5.68)] did not significantly differ. This is the first study to show that SSVEPs are significantly attenuated in the presence of concussion in male athletes. Concussed individuals' ability to generate SSVEP appear to recover following clinical recovery. The observations of this study indicate SSVEP have the potential to be a supplemental aid for the assessment and management of concussion at point-of-care.

Prevalence of Impaired Orthostasis after Concussion Injury

To determine the prevalence of orthostatic hypotension (OHypo) and hypertension (OHTN), respectively after a concussion in collegiate athletes. Orthostasis causes a gravity-dependent redistribution of blood volume to the lower extremities. The baroreflex coordinates the cardiovascular autonomic nervous system to mitigate aberrant changes in systolic blood pressure (SBP). In autonomic dysfunction (AD), impaired accommodation may lead to a clinically significant? SBP decreases (OHypo: SBP fall = 20 mm Hg) or paradoxical increases (OHTN: SBP rise = 20 mm Hg) within 3 minutes of assuming the standing (STND) posture. Concussion injuries may induce a transient state of AD. A clinical approach to surveil this state has yet to be defined. A prospective study was performed in 36 concussed (gender: 23 female, 13 male; age: 20 ± 1 years; height: 1.75 ± 0.12 meters; weight: 73 ± 14 kilograms) and 20 non-concussed athletes (gender: 12 female, 8 male; age: 21 ± 2 years; height: 1.74 ± 0.15 meters; weight: 72 ± 18 kilograms). Continuous beat-to-beat SBP was collected for 10-minutes in a resting supine position (SUP) and then for 3-minutes in the STND position within 48 hours (48H) of concussion. The average SBP was computed from the difference between SUP and the final 15 seconds of STND. SBP were then categorized: Normal (NR: SBP -15 to +15 mm Hg); Borderline OHypo (BordOHypo: SBP -16 to -19 mm Hg) and OHTN (BordOHTN: SBP +16 to +19 mm Hg); OHypo; and, OHTN. In concussed athletes, the SBP prevalence rates were 42% NR, 31% OHypo, 11% OHTN, 11% BordOHTN, and 6% BordOHypo compared to 90% NR, 5% OHypo and 5% OHTN in the non-concussed athletes. ?2 test revealed a significant difference in this distribution (p = 0.012). Within 48H of concussion injury, a combined 42% of injured athletes had an abnormal SBP response to orthostasis and a further 6% had borderline responses that warrant re-evaluation. The incidence rates for each circumstance exceeded the control group.

Sex Differences in Multidirectional Neck Muscle Strength Characteristics in High School Soccer Athletes

Weaker neck strength has been suggested as a potential risk factor of sport related concussion in female soccer athletes. The purpose of this study was to examine sex differences in neck muscle strength characteristics in multiple directions. A total of 52 high school soccer players (17 Females/35 Males) with no history of concussion participated. Subjects were instructed to perform three maximum voluntary isometric contractions for eight directions: flexion, right / left diagonal flexion, right/left lateral flexion, right/left diagonal extension, and extension. Peak force, normalized peak force, force steadiness, force ratio, and rate of force development were calculated and used for statistical analyses.

Flying After Concussion and Symptom Recovery in College Athletes and Military Cadets

Concussions are a common occurrence in young athletes. Hypobaric hypoxemia, such as that experienced during airplane travel, can potentially cause alterations to cerebral blood flow and increased neuroinflammatory response. It remains unknown whether flying early after a concussion may influence the clinical course of injury. To determine whether there is an association between concussion recovery and airplane travel in collegiate athletes and military cadets. This cohort study was conducted by the National Collegiate Athletic Association and US Department of Defense Concussion Assessment, Research, and Education Consortium from August 3, 2014, to September 13, 2018. Participant groups were categorized by those who flew within 72 hours of injury and those who did not fly. All participants included in the final analyses had complete data of interest and only 1 injury during the study. Data analysis was performed from September 2018 to March 2020. Recovery outcome measures were defined as time (in days) from injury to return to activity, school, and baseline symptoms. Symptom and headache severity scores were derived from the Sports Concussion Assessment Tool-Third Edition. Scores for both groups were taken at baseline and a median of 2 days after injury. A total of 92 participants who flew (mean [SD] age, 19.1 [1.2] years; 55 male [59.8%]) and 1383 participants who did not fly (mean [SD] age, 18.9 [1.3] years; 809 male [58.5%]) were included in the analysis of symptom recovery outcomes (analysis 1). Similarly, 100 participants who flew (mean [SD] age, 19.2 [1.2] years; 63 male [63.0%]) and 1577 participants who did not fly (mean [SD] age, 18.9 [1.3] years; 916 male [58.1%]) were included in the analysis of symptom severity outcomes (analysis 2). No significant group differences were found regarding recovery outcome measures. Likewise, there were no group differences in symptom (estimated mean difference, 0.029; 95% CI, -0.083 to 0.144; P = .67) or headache (estimated mean difference, -0.007; 95% CI, -0.094 to 0.081; P = .91) severity scores. Airplane travel early after concussion was not associated with recovery or severity of concussion symptoms. These findings may help guide future recommendations on flight travel after concussion in athletes.

Wheelchair Athlete Concussion Baseline Data: A Pilot Retrospective Analysis.

The aim of the study was to investigate whether a disabled athlete's underlying disability and concussion history impact the score on baseline testing from a disability modified Graded Symptoms Checklist, Standardized Assessment of Concussion, and Wheelchair Error Scoring System. This is a retrospective chart review of the 81 veteran wheelchair sports athletes who had baseline concussion evaluations. Demographic data including qualifying disability for the National Veterans Wheelchair Games, scores from the modified Graded Symptoms Checklist, Standardized Assessment of Concussion, and Wheelchair Error Scoring System were analyzed. Forty-three percent of wheelchair athletes reported a history of a concussion. Individuals with a history of a concussion displayed more symptoms on the modified Graded Symptoms Checklist (38.8 vs. 24.71, P = 0.0378) as did those who had a qualifying disability in the brain disorder category (54.87 vs. amputees 24.07 and spinal cord disorders 24.9, P = 0.0015). There was no difference in Standardized Assessment of Concussion examination or Wheelchair Error Scoring System scores based on concussion history or qualifying disability. Baseline symptom scores from a modified Graded Symptoms Checklist were higher in participants with a history of concussion, independent of their underlying disability, and higher if the athlete's disability was a brain disorder including multiple sclerosis and cerebral vascular accident. Scores on the Standardized Assessment of Concussion examination and Wheelchair Error Scoring System were not affected by the athlete's disability or concussion history. Baseline testing is integral for disabled athletes, especially those with underlying brain disorders and history of concussion.

Progress and Future Directions of the NCAA-DoD Concussion Assessment, Research, and Education (CARE) Consortium and Mind Matters Challenge at the US Service Academies.

Despite the significant impact that concussion has on military service members, significant gaps remain in our understanding of the optimal diagnostic, management, and return to activity/duty criteria to mitigate the consequences of concussion. In response to these significant knowledge gaps, the US Department of Defense (DoD) and the National Collegiate Athletic Association (NCAA) partnered to form the NCAA-DoD Grand Alliance in 2014. The NCAA-DoD CARE Consortium was established with the aim of creating a national multisite research network to study the clinical and neurobiological natural history of concussion in NCAA athletes and military Service Academy cadets and midshipmen. In addition to the data collected for the larger CARE Consortium effort, the service academies have pursued military-specific lines of research relevant to operational and medical readiness associated with concussion. The purpose of this article is to describe the structure of the NCAA-DoD Grand Alliance efforts at the service academies, as well as discuss military-specific research objectives and provide an overview of progress to date. A secondary objective is to discuss the challenges associated with conducting large-scale studies in the Service Academy environment and highlight future directions for concussion research endeavors across the CARE Service Academy sites.

Associations Between Neurochemistry and Gait Performance Following Concussion in Collegiate Athletes.

To evaluate the strength of associations between single-task and dual-task gait measures and posterior cingulate gyrus (PCG) neurochemicals in acutely concussed collegiate athletes. Participants were recruited from an NCAA Division 1 University. Nineteen collegiate athletes acutely (<4 days) following sports-related concussion. We acquired magnetic resonance spectroscopy (MRS) in the PCG and gait performance measurements in the participants, acutely following concussion. Linear mixed-effects models were constructed to measure the effect of gait performance, in the single- and dual-task settings, and sex on the 6 neurochemicals quantified with MRS in mmol. Correlation coefficients were also calculated to determine the direction and strength of the relationship between MRS neurochemicals and gait performance, postconcussion symptom score, and number of previous concussions. Average gait speed, average cadence, N-acetyl aspartate, choline, myo-inositol, glutathione, glutamate plus glutamine, and creatine. Single-task gait speed (P = .0056) and cadence (P = .0065) had significant effects on myo-inositol concentrations in the PCG, independent of sex, in concussed collegiate athletes. Single-task cadence (P = .047) also had a significant effect on glutathione in the PCG. No significant effects were observed between dual-task gait performance and PCG neurochemistry. These findings indicate that increased concentrations of neuroinflammatory markers in the PCG are associated with slower single-task gait performance within 4 days of sports-related concussion.

Plasma Biomarker Concentrations Associated With Return to Sport Following Sport-Related Concussion in Collegiate Athletes—A Concussion Assessment, Research, and Education (CARE) Consortium Study

Identifying plasma biomarkers associated with the amount of time an athlete may need before they return to sport (RTS) following a sport-related concussion (SRC) is important because it may help to improve the health and safety of athletes. To examine whether plasma biomarkers can differentiate collegiate athletes who RTS in less than 14 days or 14 days or more following SRC. This multicenter prospective diagnostic study, conducted by the National Collegiate Athletics Association-Department of Defense Concussion Assessment, Research, and Education Consortium, included 127 male and female athletes who had sustained an SRC while enrolled at 6 Concussion Assessment, Research, and Education Consortium Advanced Research Core sites as well as 2 partial-Advanced Research Core military service academies. Data were collected between February 2015 and May 2018. Athletes with SRC completed clinical testing and blood collection at preseason (baseline), postinjury (0-21 hours), 24 to 48 hours postinjury, time of symptom resolution, and 7 days after unrestricted RTS. A total of 3 plasma biomarkers (ie, total tau protein, glial fibrillary acidic protein [GFAP], and neurofilament light chain protein [Nf-L]) were measured using an ultrasensitive single molecule array technology and were included in the final analysis. RTS was examined between athletes who took less than 14 days vs those who took 14 days or more to RTS following SRC. Linear mixed models were used to identify significant interactions between period by RTS group. Area under the receiver operating characteristic curve analyses were conducted to examine whether these plasma biomarkers could discriminate between RTS groups. The 127 participants had a mean (SD) age of 18.9 (1.3) years, and 97 (76.4%) were men; 65 (51.2%) took less than 14 days to RTS, and 62 (48.8%) took 14 days or more to RTS. Linear mixed models identified significant associations for both mean (SE) plasma total tau (24-48 hours postinjury, <14 days RTS vs ≥14 days RTS: -0.65 [0.12] pg/mL vs -0.14 [0.14] pg/mL; P = .008) and GFAP (postinjury, 14 days RTS vs ≥14 days RTS: 4.72 [0.12] pg/mL vs 4.39 [0.11] pg/mL; P = .04). Total tau at the time of symptom resolution had acceptable discrimination power (area under the receiver operating characteristic curve, 0.75; 95% CI, 0.63-0.86; P < .001). We also examined a combined plasma biomarker panel that incorporated Nf-L, GFAP, and total tau at each period to discriminate RTS groups. Although the analyses did reach significance at each time period when combined, results indicated that they were poor at distinguishing the groups (area under the receiver operating characteristic curve, <0.7). The findings of this study suggest that measures of total tau and GFAP may identify athletes who will require more time to RTS. However, further research is needed to improve our ability to determine recovery following an SRC.

Concussions in Female Athletes: Practical Applications for the Strength and Conditioning Expert

ABSTRACT With the significant increase in concussion research and focus in the media, it is important for strength and conditioning coaches and medical experts to be clear on sex differences between how female and male concussed athletes may experience a concussion. To that end, this article offers a review of this current research, along with practical applications of the research for coaches and clinicians who work with female athletes. How should we be working with concussed female athletes specifically to assure their optimal recovery and future brain health?

Assessment of Long-Term Effects of Sports-Related Concussions: Biological Mechanisms and Exosomal Biomarkers.

Concussion or mild traumatic brain injury (mTBI) in athletes can cause persistent symptoms, known as post-concussion syndrome (PCS), and repeated injuries may increase the long-term risk for an athlete to develop neurodegenerative diseases such as chronic traumatic encephalopathy (CTE), and Alzheimer’s disease (AD). The Center for Disease Control estimates that up to 3.8 million sport-related mTBI are reported each year in the United States. Despite the magnitude of the phenomenon, there is a current lack of comprehensive prognostic indicators and research has shown that available monitoring tools are moderately sensitive to short-term concussion effects but less sensitive to long-term consequences. The overall aim of this review is to discuss novel, quantitative, and objective measurements that can predict long-term outcomes following repeated sports-related mTBIs. The specific objectives were (1) to provide an overview of the current clinical and biomechanical tools available to health practitioners to ensure recovery after mTBIs, (2) to synthesize potential biological mechanisms in animal models underlying the long-term adverse consequences of mTBIs, (3) to discuss the possible link between repeated mTBI and neurodegenerative diseases, and (4) to discuss the current knowledge about fluid biomarkers for mTBIs with a focus on novel exosomal biomarkers. The conclusions from this review are that current post-concussion clinical tests are not sufficiently sensitive to injury and do not accurately quantify post-concussion alterations associated with repeated mTBIs. In the current review, it is proposed that current practices should be amended to include a repeated symptom inventory, a cognitive assessment of executive function and impulse control, an instrumented assessment of balance, vestibulo-ocular assessments, and an improved panel of blood or exosome biomarkers.

Sport-Related Concussion in Female Athletes: A Systematic Review.

Background:Female athletes are more susceptible to sport-related concussions (SRCs) and experience worse outcomes compared with male athletes. Although numerous studies on SRC have compared the outcomes of concussions in male and female athletes after injury, research pertaining to why female athletes have worse outcomes is limited.Purpose:To determine the factors that predispose female athletes to more severe concussions than their male counterparts.Study Design:Systematic review; Level or evidence, 3.Methods:A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines. The MEDLINE, EMBASE, CINAHL, PsychINFO, and Cochrane Library databases were systematically searched on July 5 to July 20, 2018. Included were cohort, case-control, and cross-sectional studies that examined the effects of concussive and subconcussive head impacts in only female athletes of all ages, regardless of competition level. These studies were further supplemented with epidemiologic studies. Exclusion criteria included narrative reviews, single case reports, abstracts and letters to the editor, and studies related to chronic traumatic brain injury.Results:A total of 25 studies met the inclusion criteria. Female athletes appear to sustain more severe concussions than male athletes, due in part to a lower biomechanical threshold tolerance for head impacts. Additionally, concussions may alter the hypothalamic-pituitary-ovarian axis, resulting in worse symptoms and amenorrhea. Although females are more likely to report concussions than males, underreporting still exists and may result in concussions going untreated.Conclusion:This systematic review demonstrates that female athletes may be more susceptible to concussion, have prolonged symptoms after a concussion, and are more likely to report a concussion than their male counterparts. However, underreporting still exists among female athletes. Possible factors that put female athletes at a higher risk for concussions include biomechanical differences and hormonal differences. To effectively prevent, diagnose, and treat concussions in female athletes, more research is required to determine when and how such injuries are sustained. Despite sex-based differences in the clinical incidence, reporting behavior, and outcomes of SRCs, female athletes remain an understudied population, resulting in lack of sex-specific treatment guidelines for female athletes postinjury.

Lower Extremity Musculoskeletal Injury Is Associated with Increased Risk of Concussion in High School Athletes

Objectives:Previous research indicates that concussion increases the risk of lower extremity injuries (LE) after return to sport. However, no study has examined the risk of precedent lower extremity injuries and their relationship to the development of a sport related concussion (SRC). To determine if the risk of combined injuries (LE injury-SRC) is elevated in high school athletes accounting for athlete sport and gender.Methods:33,386 high school athletes were monitored over 4 seasons. 4223 LE injuries and 1132 concussions were reported. Injured athletes were identified by their school athletic trainer (AT) time-loss injury during a team-sponsored practice or game. ATs documented the date, mechanism, and sport of injury. Injured athletes were referred to a board-certified sports medicine physician for diagnoses and follow up care. Cumulative injury rates were calculated with 95% confidence intervals. Rate ratios were used to compare frequency of SRC after RTS following a LE injury. Comparisons were made overall cohort between those participating athletes with and without isolated and combined injuries as well as by gender. (α=0.05).Results:A cumulative incidence for athletes sustaining an isolated SRC was 2.3/100 athletes (95% CI= 2.1-2.5) and for isolated LE injury was 11.5/100 (95% CI=11.2-11.9) athletes. Athletes presenting with a LE injury had an increased risk (RR= 4.7; 95% CI = 4.2-5.2) of sustaining a subsequent SRC within 1 year when compared to athletes that did not suffer precedent LE injuries. Male athletes presenting with a LE injury had an increased risk (RR= 4.9; 95% CI = 4.2-5.7) of sustaining a subsequent SRC within 1 year when compared to male athletes that did not suffer precedent LE injuries. Female athletes presenting with a LE injury had an increased risk (RR= 4.4; 95% CI = 3.6-5.2) of sustaining a subsequent SRC within 1 year when compared to female athletes that did not suffer precedent LE injuries. In football, presenting with a LE injury had an increased risk (RR= 5.8; 95% CI = 4.5-7.4) of sustaining a subsequent SRC within 1 year when compared to football athletes that did not suffer precedent LE injuries.Conclusion:Our results are the first to show that high school athletes who suffer a time-loss LE injury are at 4.4-5.8 times increased risk to suffer a sports related concussion within the next year. Additional studies are warranted to confirm these findings.

A-16 The Clinical Utility of a Novel Dual-Task Assessment for Sport-Related Concussion in Collegiate Athletes

Abstract Objective To compare the clinical utility of a novel dual-task assessment for sport-related concussion (SRC) to other commonly-used clinical measures in collegiate athletes. Method Participants consisted of 38 collegiate athletes (19 concussed and 19 matched comparisons, 53% male, age = 20.0 ± 1.34 years, height = 178.2 ± 12.12 cm, mass = 83.4 ± 21.89 kg). Participants were administered the dual-task assessment, Balance Error Scoring System (BESS), Standardized Assessment of Concussion (SAC), and tandem gait (TG) test within 48 hours (T1), at 5 days (T2), and when symptom-free (T3) following a diagnosed SRC. The novel dual-task assessment consisted of concurrent administration of the SAC and TG. The ImPACT and Sensory Organization Test (SOT) were administered at T3 in alignment with the university’s concussion management policy. Sensitivity, specificity, and diagnostic accuracy using receiver operator curve analyses were calculated for each measure for T1-T3 using previously established interpretation guidelines. Results For sensitivity, a range of values were observed from T1-T3 for the dual-task (88%–37%), BESS (47%–47%), SAC (53%–26%), TG test (53%–11%). Similarly, a range of specificity values were observed for the dual-task (58%–84%), BESS (84%–63%), SAC (79%–84%), and TG test (95%–100%) from T1-T3. At T3, the ImPACT and SOT were observed to have a sensitivity of 32% and 100% and specificity of 16% and 100%, respectively. A range of diagnostic accuracy values were observed from T1-T3 for the dual-task (84%–62%), BESS (59%–50%), SAC (64%–56%), TG test (82%–71%), ImPACT (T3 = 66%), and SOT (T3 = 50%). Conclusions The dual-task assessment had comparable or higher diagnostic accuracy as other commonly-used clinical measures of SRC throughout clinical recovery in collegiate athletes.

A-09 Time to Unrestricted Participation Following Sport-Related Concussion in High School Athletes

Abstract Objective To measure time-to-unrestricted participation in high school athletes following a sport-related concussion (SRC) diagnosis. Method This was a descriptive epidemiological study using the Michigan High School Athletic Association (MHSAA) online Head Injury Reporting System (HIRS). This study included 10,411 (65.9%) male and 5,412 (34.1%) female SRC cases that occurred in 20 sports with greater than 30 SRC cases during the 2015–2016 to 2018–2019 academic years. The HIRS includes dates for SRC injury events and medical clearance for unrestricted return-to-participation for each case; dates were used to calculate recovery time. Kaplan-Meier time-to-event analysis identified crude proportions of athletes that had not obtained medical clearance in weekly increments (e.g., 7 days, 14 days, 21 days, 28 days, 35 days) across sports. Results The median time-to-unrestricted participation was 11 days. Overall, 71.8% of SRC cases took longer than 7 days to return, 29.6% of SRC cases took longer than 14 days, 13.1% of cases took longer than 21 days to return, and 6.5% took longer than 28 days to return to their respective sports. Results by sport show that over 25% of gymnasts took longer than 28 days to return-to-unrestricted participation, followed by competitive cheerleaders (15.5%), wrestlers (12.1%), and male divers (12.0%). Conclusions Almost one in three high school athletes with SRC took longer than 14 days to return-to-unrestricted participation. These results serve as proportional time estimates for return-to-unrestricted participation across a sample of 20 high school sports; and provide rationale to further evaluate recovery patterns in individual sport groups.

Symptom profiles and postural control after concussion in female artistic athletes

ABSTRACT Objectives The purpose of our investigation was to compare post-concussion symptom profiles and postural control measures among female youth artistic athletes (gymnasts and cheerleaders) relative to female ball sport athletes (volleyball or basketball). Methods/Findings We compared 27 artistic athletes (median age = 15.0 years; evaluated median = 13 days post-injury) and 49 ball sport athletes (median age = 15.3 years; evaluated median = 10 days post-injury) within 21 days of sustaining a concussion on measures of symptom profiles and postural control (Balance Error Scoring System [BESS]), tandem gait, and Romberg tests. After adjusting for the independent effect of time from injury-evaluation, concussion history, and pre-morbid migraine history, we observed that artistic athletes performed the BESS tandem stance foam condition with fewer errors than ball sport athletes (β = −2.4; 95% CI = −4.7, −0.2; p = .03). Artistic athletes demonstrated a higher, yet not statistically significant, headache severity than ball sport athletes (median = 4.5 vs 4.0, p = .07). Conclusions Overall, artistic athletes had similar symptom profiles to ball sport athletes. Postural control measures, other than the BESS tandem stance foam condition, were not significantly different from ball sport athletes. This suggests that although their sports may require higher levels of balance, artistic athletes’ performance on post-concussion balance tests may be similar to athletes of other disciplines.

Concussion knowledge, attitudes and behaviour in equestrian athletes

ObjectiveTo determine knowledge, attitudes and behaviour towards concussion in adult equestrian athletes. DesignNationwide, cross-sectional, questionnaire. MethodsParticipants were recruited via advertisements circulated through social media, community presentations and equestrian organisations. Participants were sent a web link to an online questionnaire previously designed for high school athletes and modified to ensure relevance to equestrian activities. The percentage of correct responses per item and a total knowledge score were calculated. Differences in concussion knowledge by age, sex, level of experience and previous history of concussion were explored using t-tests, 95% confidence intervals (CI) and effect sizes. ResultsThe questionnaire was completed by 1486 participants (Mean age=39.1±15.4). Knowledge of what concussion was, how to recognise it and key symptoms (except poor sleep) was high (>80%). In contrast, awareness of guidelines was moderate (56%) and inability of helmets to prevent concussion was low (12%). Significantly higher levels of knowledge of concussion were identified in females compared with males (t=-6.55 p<0.001, 95%CI=-3.26 to -1.75). The majority (87%) of participants reported that a helmet should be replaced after a fall, yet 46% reported re-using a helmet following a hit to the head. ConclusionsKnowledge of and attitudes towards concussion were positive. However, there were knowledge gaps and discrepancies between some attitudes and behaviour on some aspects of concussion. Targeted campaigns to promote awareness of concussion and improve recognition and onward management are needed. Education related to equestrian activities such as helmet use and injury mechanisms is needed to change behaviour and minimise the risk of injury.