Does Exercise Increase Vestibular and Ocular Motor Symptom Detection After Sport-Related Concussion?

BACKGROUND AND PURPOSE: Postconcussive vestibular and ocular motor symptoms are common and contribute to longer recovery. The Vestibular/Ocular Motor Screening (VOMS) is used to detect such symptoms, but a VOMS performed at rest may miss symptoms that are only provoked by exertion. Supervised exercise challenges (SECs) have been shown to detect concussion-related symptoms provoked by physical exertion. The purpose of this study was to determine whether athletes undergoing an SEC will exhibit greater symptom provocation with the VOMS compared to a VOMS performed at rest prior to an SEC. METHODS: Thirty-six athletes (58.3% male) between ages 10 and 18 years and within 30 days of concussion were included. All participants completed VOMS assessments at rest and immediately after an SEC. VOMS total symptom score increases were calculated for both pre- and post-SEC assessments compared using Wilcoxon ranked sum tests. The frequencies of positive assessments for each VOMS item were compared using McNemar's test. RESULTS: There were significant increases in post-SEC symptom provocation scores compared with pre-SEC scores for all VOMS items. The post-SEC VOMS identified 29 participants (80.6%) as positive in at least 1 VOMS item compared with 21 participants (58.3%) identified as positive pre-SEC (P = 0.008). For all VOMS items, the post-SEC VOMS identified participants who were previously negative on a pre-SEC VOMS but became positive after the SEC. DISCUSSION AND CONCLUSIONS: An SEC performed prior to a VOMS assessment may increase the detection of vestibular and ocular motor symptoms that may be missed if the VOMS was performed only at rest.Video Abstract available for more insight from the authors (see the Video Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A342).

Use of Supervised Exercise During Recovery Following Sports-Related Concussion.

OBJECTIVE: To assess the safety of supervised exercise (SE) in acute sport-related concussion (SRC) and its influence on recovery. DESIGN: Retrospective cohort study. SETTING: University SRC clinic at a tertiary care center. PATIENTS: One hundred ninety-four consecutive new patient charts were reviewed. Patients were included if they were seen within 30 days of sustaining a SRC, and their medical records included all required data elements. One hundred twenty-six patients were included in the analysis. INTERVENTIONS: Symptomatic patients who initiated SE within 16 days of SRC (n = 24) were compared with those who did not undergo SE or initiated SE after postinjury day 16 (n = 84). Age, sex, history of previous concussions, injury severity, relevant comorbidities, and other treatments received were included in the analysis. MAIN OUTCOME MEASURES: The association between early SE and clearance for return to sport was determined using a hazard ratio (HR). The number of days from SRC until clearance for return to sport and the number of days symptomatic from concussion were also compared between early SE and nonearly SE cohorts. RESULTS: No serious adverse events occurred in the early SE group. Early SE was associated with earlier return to sport (HR = 2.35, P = 0.030). The early SE group had fewer days from SRC until clearance for return to sport (mean 26.5 ± 11.2 days vs 35.1 ± 26.5 days, P = 0.020). There was a trend toward fewer symptomatic days in the early SE group (P = 0.054). CONCLUSION: Early SE performed in the symptomatic stage of SRC was safe and associated with earlier return to sport.

Concussion, sensation-seeking and substance use among US adolescents.

BACKGROUND: No large-scale epidemiological survey of adolescents in the US has assessed the association between lifetime history of concussion, propensity toward sensation-seeking, and recent substance use. Methods: This study assesses the association between lifetime history of diagnosed concussions, sensation-seeking, and recent substance use (i.e., cigarette use, binge drinking, marijuana use, illicit drug use, and nonmedical prescription drug use) using the 2016 and 2017 Monitoring the Future study of 25,408 8th, 10th, and 12th graders. Results: Lifetime diagnosis of concussion was associated with greater odds of past 30-day/2-week substance use. Adolescents who indicated multiple diagnosed concussions (versus none) had two times greater odds of all types of recent substance use, after adjusting for potential confounding factors. Adolescents indicating multiple diagnosed concussions also had higher adjusted odds of cigarette use, binge drinking, and marijuana use) when compared to adolescents who only indicated one diagnosed concussion. Accounting for adolescents' propensity toward sensation-seeking did not significantly change the association between substance use and multiple diagnosed concussions. Conclusions: This study provides needed epidemiological data regarding concussion and substance use among US adolescents. Exposure to a single diagnosed concussion is associated with a modest increase in the risk of substance use and this association increases with the accumulation of multiple diagnosed concussions. These associations hold when controlling for sensation-seeking. Substance use prevention efforts should be directed toward adolescents who have a history of multiple concussions.

No Seasonal Changes in Cognitive Functioning Among High School Football Athletes: Implementation of a Novel Electrophysiological Measure and Standard Clinical Measures.

OBJECTIVE: To evaluate neuroelectric and cognitive function relative to a season of football participation. Cognitive and neuroelectric function declines are hypothesized to be present in football athletes. DESIGN: Observational. SETTING: Athletic fields and research laboratory. PATIENTS (OR PARTICIPANTS): Seventy-seven high school athletes (15.9 + 0.9 years, 178.6 + 7.2 cm, 74.4 + 14.7 kg, and 0.8 + 0.8 self-reported concussions) participating in football (n = 46) and noncontact sports (n = 31). INTERVENTIONS (OR ASSESSMENT OF RISK FACTORS): All athletes completed preseason, midseason, and postseason assessments of cognitive and neuroelectric function, self-reported symptoms, and quality of life. All athletes participated in their respective sports without intervention, while head impact exposure in football athletes was tracked using the Head Impact Telemetry System. MAIN OUTCOME MEASURES: Cognitive performance was based on Cogstate computerized cognitive assessment tool processing speed, attention, learning, working memory speed, and working memory accuracy scores. ElMindA brain network activation amplitude, synchronization, timing and connectivity brain network activation scores demarcated neuroelectric performance. Quality of life was assessed on the Health Behavior Inventory and Satisfaction with Life Scale and symptoms on the SCAT3 inventory. RESULTS: Football and control sport athletes did not show declines in cognitive or neuroelectric function, quality-of-life measures, or symptom reports across a season of sport participation. CONCLUSIONS: These findings refute the notion that routine football participation places athletes at risk for acute cognitive declines. The lack of impairment may be associated with no association with head impacts and cognitive function, increased physical activity offsetting any declines, and/or test sensitivity. How these findings are associated with long-term cognitive function is unknown.

Is Migraine Headache Associated With Concussion in Athletes? A Case-Control Study.

OBJECTIVE: The purpose of this study was to investigate the association between migraine headache and concussion in athletes. DESIGN: Case-control observational study. SETTING: A university-associated combined sports neurology and orthopedic sports medicine clinic. PARTICIPANTS: A total of 221 male (n = 140) and female (n = 81) athletes aged 12 to 24 years, including 115 concussion cases (52%) and 106 orthopedic controls (48%), were included in this study. INTERVENTIONS: Participants completed a one-page questionnaire that recorded their age, sex, reason for visit (concussion vs any other injury), concussion history, and self/immediate family member migraine headache history. MAIN OUTCOME MEASURES: The odds of having a previous history of migraine headache were compared in the concussion group versus orthopedic controls. RESULTS: Controlling for between-group differences in age and sex, there was a significant positive association between concussion group status and history of migraine headache [adjusted odds ratio (OR), 1.90; 95% confidence interval (CI), 1.03-3.50. P = 0.039]. However, when including a previous concussion history in the statistical model, this relationship failed to reach significance [adjusted OR, 1.68; 95% CI, 0.89-3.16. P = 0.107]. CONCLUSIONS: These results suggest that there is an association between migraine headache and concussion in athletes, but the cause-effect nature of this relationship cannot be determined. Migraine headache should be considered a modifying factor when caring for concussed athletes.

Stability of an ERP-based measure of brain network activation (BNA) in athletes: A new electrophysiological assessment tool for concussion.

PRIMARY OBJECTIVE: To determine test-re-test reliabilities of novel Evoked Response Potential (ERP)-based Brain Network Activation (BNA) scores in healthy athletes. RESEARCH DESIGN: Observational, repeated-measures study. METHODS AND DESIGN: Forty-two healthy male and female high school and collegiate athletes completed auditory oddball and go/no-go ERP assessments at baseline, 1 week, 6 weeks and 1 year. The BNA algorithm was applied to the ERP data, considering electrode location, frequency band, peak latency and normalized amplitude to generate seven unique BNA scores for each testing session. MAIN OUTCOMES AND RESULTS: Mean BNA scores, intra-class correlation coefficient (ICC) values and reliable change (RC) values were calculated for each of the seven BNA networks. BNA scores ranged from 46.3 ± 34.9 to 69.9 ± 22.8, ICC values ranged from 0.46-0.65 and 95% RC values ranged from 38.3-68.1 across the seven networks. CONCLUSIONS: The wide range of BNA scores observed in this population of healthy athletes suggests that a single BNA score or set of BNA scores from a single after-injury test session may be difficult to interpret in isolation without knowledge of the athlete's own baseline BNA score(s) and/or the results of serial tests performed at additional time points. The stability of each BNA network should be considered when interpreting test-re-test BNA score changes.

RELIABILITY AND CRITERION VALIDITY OF A NOVEL CLINICAL TEST OF SIMPLE AND COMPLEX REACTION TIME IN ATHLETES.

Slowed reaction time (RT) represents both a risk factor for and a consequence of sport concussion. The purpose of this study was to determine the reliability and criterion validity of a novel clinical test of simple and complex RT, called RT(clin), in contact sport athletes. Both tasks were adapted from the well-known ruler drop test of RT and involve manually grasping a falling vertical shaft upon its release, with the complex task employing a go/no-go paradigm based on a light cue. In 46 healthy contact sport athletes (24 men; M = 16.3 yr., SD = 5.0; 22 women: M age = 15.0 yr., SD = 4.0) whose sports included soccer, ice hockey, American football, martial arts, wrestling, and lacrosse, the latency and accuracy of simple and complex RT(clin) had acceptable test-retest and inter-rater reliabilities and correlated with a computerized criterion standard, the Axon Computerized Cognitive Assessment Tool. Medium to large effect sizes were found. The novel RT(clin) tests have acceptable reliability and criterion validity for clinical use and hold promise as concussion assessment tools.

Effect of sport-related concussion on clinically measured simple reaction time.

BACKGROUND: Reaction time (RT) is a valuable component of the sport concussion assessment battery. RT is typically measured using computers running specialised software, which limits its applicability in some athletic settings and populations. To address this, we developed a simple clinical test of RT (RTclin) that involves grasping a falling measuring stick. PURPOSE: To determine the effect of concussion on RTclin and its sensitivity and specificity for concussion. MATERIALS AND METHODS: Concussed athletes (n=28) and non-concussed control team-mates (n=28) completed RTclin assessments at baseline and within 48 h of injury. Repeated measures analysis of variance compared mean baseline and follow-up RTclin values between groups. Sensitivity and specificity were calculated over a range of reliable change confidence levels. RESULTS: RTclin differed significantly between groups (p<0.001): there was significant prolongation from baseline to postinjury in the concussed group (p=0.003), with a trend towards improvement in the control group (p=0.058). Sensitivity and specificity were maximised when a critical change value of 0 ms was applied (ie, any increase in RTclin from baseline was interpreted as abnormal), which corresponded to a sensitivity of 75%, specificity of 68% and a 65% reliable change confidence level. CONCLUSIONS: RTclin appears sensitive to the effects of concussion and distinguished concussed and non-concussed athletes with similar sensitivity and specificity to other commonly used concussion assessment tools. Given its simplicity, low cost and minimal time requirement, RTclin should be considered a viable component of the sports medicine provider's multifaceted concussion assessment battery.

Headache Characteristics of Pediatric Sport-Related Concussion.

BACKGROUND: Headache is among the most common symptoms following concussion, yet headache after concussion (HAC) remains poorly characterized. This study describes headache characteristics over the first four weeks following pediatric sport-related concussion. METHODS: This is a retrospective case series of 87 athletes (mean: 14.9 years; range: 8.4-18.8 years; 38% female) treated in a specialty sports concussion clinic within 28 days of injury. Primary outcomes of headache consistency, frequency, duration, and associated migrainous symptoms were assessed at immediate (0 to 48 h) and weekly time points over the first 28 days post-injury. Generalized mixed linear models compared headache characteristics across time points. Secondary analyses compared each outcome by as-needed analgesic use. RESULTS: During the immediate post-injury period, headache was more often constant (p = 0.002) and associated with migrainous symptoms (p < 0.001). By the third week post-injury, episodic headache was more prevalent (p < 0.001). Most patients (54%) transitioned from constant, migrainous headache to episodic, non-migrainous headache. This finding was uninfluenced by as-needed analgesic medication use. CONCLUSIONS: These findings document the trajectory of HAC. Future studies should assess relationships between initial headache characteristics and recovery.

Understanding Abnormal Examination Findings During Concussion Recovery: A Retrospective Chart Review.

Background and Objective: Physical examination findings in athletes with sport-related concussion (SRC) are not well described in the literature. The objective of this study was to describe physical examination findings during the first month following concussion in athletes, with a focus on the effect of sex, age, and time since injury. Methods: This was a retrospective electronic medical record (EMR) review of physical examination findings in 500 patients aged 6-24 who were initially seen within 15 days of SRC at a multidisciplinary outpatient academic concussion clinic between 2017 and 2019. A standardized concussion examination built in the EMR recorded mental status, cranial nerve, vestibulo-ocular motor screen, and balance findings for all patients. The primary outcome was the frequency of abnormal examination findings during the first 30 days postinjury, which was further analyzed by sex, age, and time since injury using mixed logistic regression models. Results: The most common abnormal examination findings overall were eyes-closed single-leg stance, vestibular-ocular reflex, visual motion sensitivity, the neck examination, and eyes-closed tandem stance. Abnormal findings were more frequent in female athletes for vestibular ocular reflex and visual motion sensitivity. The frequency of abnormal findings increased with age for vestibulo-ocular reflex, visual motion sensitivity, the neck examination, convergence testing, and eyes-open single-leg stance, whereas abnormalities decreased in frequency with age for eyes-open tandem stance and tandem gait. The frequency of abnormal findings generally decreased with time over the first 4 weeks following injury. Discussion: A comprehensive physical examination is pivotal for evaluation of athletes with concussion. These findings highlight high-yield components of the concussion examination and support use of these examination components as injury markers. Future work should investigate associations between physical examination findings and postconcussion symptoms and recovery outcomes. Classification of Evidence: This retrospective cohort study provides Class IV evidence that neurologic examination with specifically designed clinical tests are helpful for diagnosis of traumatic brain injury in young athletes at age 6-24.

Postinjury Outcomes After Non-Sport-Related Concussion: A CARE Consortium Study.

CONTEXT: Concussion research has primarily focused on sport-related mechanisms and excluded non-sport-related mechanisms. In adult populations, non-sport-related concussions (non-SRCs) demonstrated worse clinical outcomes compared with sport-related concussions (SRCs); however, investigations of non-SRCs in college-aged patients are limited. OBJECTIVES: To examine clinical outcomes in collegiate athletes with non-SRCs compared with SRCs and explore sex differences in outcomes among collegiate athletes with non-SRCs. DESIGN: Prospective cohort study. SETTING: Clinical setting. PATIENTS OR OTHER PARTICIPANTS: A total of 3500 athletes were included (n = 555 with non-SRCs, 42.5% female) from colleges or universities and service academies participating in the National Collegiate Athletic Association Department of Defense Concussion Assessment, Research and Education (CARE) Consortium. MAIN OUTCOME MEASURE(S): Dichotomous outcomes (yes or no) consisted of immediate reporting, mental status alterations, loss of consciousness, posttraumatic amnesia, retrograde amnesia, motor impairments, delayed symptom presentation, and required hospital transport. Continuous outcomes were symptom severity, days with concussion symptoms, and days lost to injury. Data were collected within 24 to 48 hours of injury and at return to play. Adjusted relative risks (ARRs) compared the likelihood of dichotomous outcomes by mechanism and by sex within patients with non-SRCs. Multivariate negative binomial regressions were used to assess group differences in continuous variables. RESULTS: Athletes with non-SRCs were less likely to report immediately (ARR = 0.73, 95% CI = 0.65, 0.81) and more likely to report delayed symptom presentation (ARR = 1.17, 95% CI = 1.03, 1.32), loss of consciousness (ARR = 3.15, 95% CI = 2.32, 4.28), retrograde amnesia (ARR = 1.77, 95% CI = 1.22, 2.57), and motor impairment (ARR = 1.45, 95% CI = 1.14, 1.84). Athletes with non-SRCs described greater symptom severity, more symptomatic days, and more days lost to injury (P < .001) compared with those who had SRCs. Within the non-SRC group, female athletes indicated greater symptom severity, more symptomatic days, and more days lost to injury (P < .03) than male athletes. CONCLUSIONS: Athletes with non-SRCs had worse postinjury outcomes compared with those who had SRCs, and female athletes with non-SRCs had worse recovery metrics than male athletes. Our findings suggest that further investigation of individuals with non-SRCs is needed to improve concussion reporting and management.

Sex Differences in Recovery Trajectories of Assessments for Sport-Related Concussion Among NCAA Athletes: A CARE Consortium Study.

OBJECTIVES: The purpose of this study was to determine sex differences in recovery trajectories of assessments for sport-related concussion using Concussion Assessment, Research and Education (CARE) Consortium data. METHODS: National Collegiate Athletic Association athletes (N = 906; 61% female) from sex-comparable sports completed a pre-season baseline assessment and post-sport-related concussion assessments within 6 h of injury, 24-48 h, when they initiated their return to play progression, when they were cleared for unrestricted return to play, and 6 months post-injury. Assessments included the Standardized Assessment of Concussion, Balance Error Scoring System, Brief Symptom Inventory-18, Immediate Post-concussion Assessment and Cognitive Testing (ImPACT), Sport Concussion Assessment Tool-3 symptom evaluation, Clinical Reaction Time, King-Devick test, Vestibular Ocular Motor Screen, 12-item Short-Form Health Survey, Hospital Anxiety and Depression Scale, and Satisfaction with Life Scale. RESULTS: Only the Vestibular Ocular Motor Screen Total Symptom Score at the 24-48 h timepoint (p = 0.005) was statistically significantly different between sexes. Specifically, female athletes (mean = 60.2, 95% confidence interval [CI] 51.5-70.4) had higher Vestibular Ocular Motor Screen Total Symptom Scores than male athletes (mean = 36.9, 95% CI 27.6-49.3), but this difference resolved by the time of return-to-play initiation (female athletes, mean = 1.8, 95% CI 1.1-2.9; male athletes, mean = 4.1, 95% CI 1.5-10.9). CONCLUSIONS: Sport-related concussion recovery trajectories for most assessments were similar for female and male National Collegiate Athletic Association athletes except for Vestibular Ocular Motor Screen symptoms within 48 h of sport-related concussion, which was greater in female athletes. Female athletes had a greater symptom burden across all timepoints, suggesting that cross-sectional observations may indicate sex differences despite similar recovery trajectories.

Optimizing Concussion Care Seeking: Using Machine Learning to Predict Delayed Concussion Reporting.

BACKGROUND: Early medical attention after concussion may minimize symptom duration and burden; however, many concussions are undiagnosed or have a delay in diagnosis after injury. Many concussion symptoms (eg, headache, dizziness) are not visible, meaning that early identification is often contingent on individuals reporting their injury to medical staff. A fundamental understanding of the types and levels of factors that explain when concussions are reported can help identify promising directions for intervention. PURPOSE: To identify individual and institutional factors that predict immediate (vs delayed) injury reporting. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This study was a secondary analysis of data from the Concussion Assessment, Research and Education (CARE) Consortium study. The sample included 3213 collegiate athletes and military service academy cadets who were diagnosed with a concussion during the study period. Participants were from 27 civilian institutions and 3 military institutions in the United States. Machine learning techniques were used to build models predicting who would report an injury immediately after a concussive event (measured by an athletic trainer denoting the injury as being reported "immediately" or "at a delay"), including both individual athlete/cadet and institutional characteristics. RESULTS: In the sample as a whole, combining individual factors enabled prediction of reporting immediacy, with mean accuracies between 55.8% and 62.6%, depending on classifier type and sample subset; adding institutional factors improved reporting prediction accuracies by 1 to 6 percentage points. At the individual level, injury-related altered mental status and loss of consciousness were most predictive of immediate reporting, which may be the result of observable signs leading to the injury report being externally mediated. At the institutional level, important attributes included athletic department annual revenue and ratio of athletes to athletic trainers. CONCLUSION: Further study is needed on the pathways through which institutional decisions about resource allocation, including decisions about sports medicine staffing, may contribute to reporting immediacy. More broadly, the relatively low accuracy of the machine learning models tested suggests the importance of continued expansion in how reporting is understood and facilitated.

The Prevalence and Influence of New or Worsened Neck Pain After a Sport-Related Concussion in Collegiate Athletes: A Study From the CARE Consortium.

BACKGROUND: Neck pain in a concussion population is an emerging area of study that has been shown to have a negative influence on recovery. This effect has not yet been studied in collegiate athletes. HYPOTHESIS: New or worsened neck pain is common after a concussion (>30%), negatively influences recovery, and is associated with patient sex and level of contact in sport. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Varsity-level athletes from 29 National Collegiate Athletic Association member institutions as well as nonvarsity sport athletes at military service academies were eligible for enrollment. Participants completed a preseason baseline assessment and follow-up assessments at 6 and 24 to 48 hours after a concussion, when they were symptom-free, and when they returned to unrestricted play. Data collection occurred between January 2014 and September 2018. RESULTS: A total of 2163 injuries were studied. New or worsened neck pain was reported with 47.0% of injuries. New or worsened neck pain was associated with patient sex (higher in female athletes), an altered mental status after the injury, the mechanism of injury, and what the athlete collided with. The presence of new/worsened neck pain was associated with delayed recovery. Those with new or worsened neck pain had 11.1 days of symptoms versus 8.8 days in those without (P < .001). They were also less likely to have a resolution of self-reported symptoms in ≤7 days (P < .001). However, the mean duration of the return-to-play protocol was not significantly different for those with new or worsened neck pain (7.5 ± 7.7 days) than those without (7.4 ± 8.3 days) (P = .592). CONCLUSION: This novel study shows that neck pain was common in collegiate athletes sustaining a concussion, was influenced by many factors, and negatively affected recovery.

Association of Premorbid Anxiety and Depression Symptoms in Concussion Recovery in Collegiate Student-Athletes.

BACKGROUND: Mental health disorders are linked to prolonged concussion symptoms. However, the association of premorbid anxiety/depression symptoms with postconcussion return-to-play timelines and total symptom burden is unclear. OBJECTIVE: To examine the association of self-reported premorbid anxiety/depression symptoms in collegiate student-athletes with (1) recovery times until asymptomatic, (2) return-to-play, and (3) postconcussion symptom burden. STUDY DESIGN: Athletes in the Concussion Assessment, Research and Education Consortium completed baseline concussion assessments (Sport Concussion Assessment Tool [SCAT3] and Brief Symptom Inventory-18 [BSI-18]). Athletes were tested postinjury at <6 hours, 24 to 48 hours, time of asymptomatic and start of return-to-play protocol, unrestricted return-to-play, and 6 months after injury. Injured athletes were categorized into 4 groups based on BSI-18 scores: (1) B-ANX, elevated anxiety symptoms only; (2) B-DEP, elevated depression symptoms only; (3) B-ANX&DEP, elevated anxiety and depression symptoms; and (4) B-NEITHER, no elevated anxiety or depression symptoms. Relationship between age, sex, BSI-18 group, SCAT3 total symptom and severity scores, and time to asymptomatic status and return-to-play was assessed with Pearson's chi-squared test and robust analysis of variance. LEVEL OF EVIDENCE: Level 3. RESULTS: Among 1329 athletes with 1352 concussions, no respondents had a self-reported premorbid diagnosis of anxiety/depression. There was no difference in time until asymptomatic or time until return-to-play between BSI-18 groups (P = 0.15 and P = 0.11, respectively). B-ANX, B-DEP, and B-ANX&DEP groups did not have higher total symptom or severity scores postinjury compared with the B-NEITHER group. CONCLUSION: Baseline anxiety/depression symptoms in collegiate student-athletes without a mental health diagnosis are not associated with longer recovery times until asymptomatic, longer time to return-to-play, or higher postconcussion total symptom and severity scores compared with athletes without baseline symptoms. CLINICAL RELEVANCE: Anxiety and depression symptoms without a clear mental health diagnosis should be considered differently from other comorbidities when discussing prolonged recovery in collegiate student-athletes.

Mechanisms of Injury Leading to Concussions in Collegiate Soccer Players: A CARE Consortium Study.

BACKGROUND: Few previous studies have investigated how different injury mechanisms leading to sport-related concussion (SRC) in soccer may affect outcomes. PURPOSE: To describe injury mechanisms and evaluate injury mechanisms as predictors of symptom severity, return to play (RTP) initiation, and unrestricted RTP (URTP) in a cohort of collegiate soccer players. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The Concussion Assessment, Research and Education (CARE) Consortium database was used. The mechanism of injury was categorized into head-to-ball, head-to-head, head-to-body, and head-to-ground/equipment. Baseline/acute injury characteristics-including Sports Concussion Assessment Tool-3 total symptom severity (TSS), loss of consciousness (LOC), and altered mental status (AMS); descriptive data; and recovery (RTP and URTP)-were compared. Multivariable regression and Weibull models were used to assess the predictive value of the mechanism of injury on TSS and RTP/URTP, respectively. RESULTS: Among 391 soccer SRCs, 32.7% were attributed to a head-to-ball mechanism, 27.9% to a head-to-body mechanism, 21.7% to a head-to-head mechanism, and 17.6% to a head-to-ground/equipment mechanism. Event type was significantly associated with injury mechanism [χ2(3) = 63; P < .001), such that more head-to-ball concussions occurred in practice sessions (n = 92 [51.1%] vs n = 36 [17.1%]) and more head-to-head (n = 65 [30.8%] vs n = 20 [11.1]) and head-to-body (n = 76 [36%] vs n = 33 [18.3%]) concussions occurred in competition. The primary position was significantly associated with injury mechanism [χ2(3) = 24; P < .004], with goalkeepers having no SRCs from the head-to-head mechanism (n = 0 [0%]) and forward players having the least head-to-body mechanism (n = 15 [19.2%]). LOC was also associated with injury mechanism (P = .034), with LOC being most prevalent in head-to-ground/equipment. Finally, AMS was most prevalent in head-to-ball (n = 54 [34.2%]) and head-to-body (n = 48 [30.4%]) mechanisms [χ2(3) = 9; P = .029]. In our multivariable models, the mechanism was not a predictor of TSS or RTP; however, it was associated with URTP (P = .044), with head-to-equipment/ground injuries resulting in the shortest mean number of days (14 ± 9.1 days) to URTP and the head-to-ball mechanism the longest (18.6 ± 21.6 days). CONCLUSION: The mechanism of injury differed by event type and primary position, and LOC and AMS were different across mechanisms. Even though the mechanism of injury was not a significant predictor of acute symptom burden or time until RTP initiation, those with head-to-equipment/ground injuries spent the shortest time until URTP, and those with head-to-ball injuries had the longest time until URTP.

How gender and task difficulty affect a sport-protective response in young adults.

We tested the hypotheses that gender and task difficulty affect the reaction, movement, and total response times associated with performing a head protective response. Twenty-four healthy young adults (13 females) performed a protective response by raising their hands from waist level to block a foam ball fired at their head from an air cannon. Participants initially stood 8.25 m away from the cannon ('low difficulty'), and were moved successively closer in 60 cm increments until they failed to block at least five of eight balls ('high difficulty'). Limb motion was quantified using optoelectronic markers on the participants' left wrist. Males had significantly faster total response times (P = 0.042), a trend towards faster movement times (P = 0.054), and faster peak wrist velocity (P < 0.001) and acceleration (P = 0.032) than females. Reaction time, movement time, and total response time were significantly faster under high difficulty conditions for both genders (P < 0.001). This study suggests that baseball and softball pitchers and fielders should have sufficient time to protect their head from a batted ball under optimal conditions if they are adequately prepared for the task.

Early Exercise is Associated with Faster Concussion Recovery Among Collegiate Athletes: Findings from the NCAA-DoD CARE Consortium.

BACKGROUND: Growing evidence indicates early exercise may improve symptoms and reduce clinical recovery time after concussion, but research examining collegiate student-athletes is scarce. OBJECTIVE: The aim of this study was to compare symptom recovery time, clinical recovery time, and persisting post-concussion symptom (i.e., symptoms ≥ 28 days) prevalence by the timing of light exercise initiation before the graded return to play (RTP) protocol among concussed participants. METHODS: Collegiate student-athletes (n = 1228; age 18.4 ± 0.9 years; 56.5% male, 76.3% division I; 33.7% ≥ 1 prior concussion) across 30 institutions enrolled in the CARE Consortium completed post-concussion assessments and were monitored over time. Symptom recovery (days from injury to symptom resolution) and clinical recovery (days from injury to return to play protocol completion) was determined by the student-athletes' clinicians. Student-athletes were categorized by timing of light exercise initiation. Early (< 2 days post-concussion; n = 161), typical (3-7 days post-concussion; n = 281), and late exercise (≥ 8 days post-concussion; n = 169) groups were compared with the no-exercise group (n = 617; i.e., did not exercise prior to beginning the RTP protocol) for all analyses. Multivariable Cox regression models with hazard ratios (HR) and survival curves and a multivariable binomial regression model with prevalence ratios (PR) compared recovery outcomes between exercise groups while accounting for covariates. RESULTS: Compared to the no-exercise group, the early exercise group was 92% more probable to experience symptom recovery (HR 1.92; 95% CI 1.57-2.36), 88% more probable to reach clinical recovery (HR 1.88; 95% CI 1.55-2.28) and took a median of 2.4 and 3.2 days less to recover, respectively. The late exercise group relative to the no-exercise group was 57% less probable to reach symptom recovery (HR 0.43; 95% CI 0.35-0.53), 46% less probable to achieve clinical recovery (HR 0.54; 95% CI 0.45-0.66) and took 5.3 days and 5.7 days more to recover, respectively. The typical exercise group did not differ in hazard for symptom or clinical recovery (p ≥ 0.329) compared with the no-exercise group. The prevalence of persisting post-concussion symptoms in the combined sample was 6.6%. Early exercise had 4% lower prevalence (PR 0.96, 95% CI 0.94-0.99) and typical exercise had 3% lower prevalence (PR 0.97, 95% CI 0.94-0.99) of persisting post-concussion symptoms, while the late exercise group had an elevated prevalence (PR 1.11, 95% CI 1.04-1.18) compared with the no-exercise group. CONCLUSION: Exercise < 2 days post-concussion was associated with more probable and faster symptom and clinical recovery, and lower persisting post-concussion symptom prevalence. When considering our findings and existing literature, qualified clinicians may implement early exercise into their clinical practice to provide therapeutic treatment and improve student-athlete recovery.

Initial Mild Traumatic Brain Injury Characteristics and Recovery Patterns Among Females Across the United States Military Service Academies: A Report from the NCAA-DoD CARE Consortium.

Mild traumatic brain injury (mTBI) has been described in the United States (US) military service academy cadet population, but female-specific characteristics and recovery outcomes are poorly characterized despite sex being a confounder. Our objective was to describe female cadets' initial characteristics, assessment performance, and return-to-activity outcomes post-mTBI. Female cadets (n = 472) from the four US military service academies who experienced a mTBI completed standardized mTBI assessments from pre-injury to acute initial injury and unrestricted return-to-duty (uRTD). Initial injury presentation characteristics (e.g., delayed symptoms, retrograde amnesia) and return-to-activity outcomes [i.e., return-to-learn, initiate return-to-duty protocol (iRTD), uRTD] were documented. Descriptive statistics summarized female cadets' injury characteristics, return-to-activity outcomes, and post-mTBI assessment performance change categorization (worsened, unchanged, improved) relative to pre-injury baseline using established change score confidence rank criteria for each assessment score. The median (interquartile range) days to return-to-learn (n = 157) was 7.0 (3.0-14.0), to iRTD (n = 412) was 14.7 (8.6-25.8), and to uRTD (n = 431) was 26.0 (17.7-41.8). The majority experienced worse SCAT total symptom severity (77.8%) and ImPACT reaction time (97.0%) acutely < 24-h versus baseline, but unchanged BESS total errors (75.2%), SAC total score (72%), BSI-18 total score (69.6%), and ImPACT verbal memory (62.3%), visual memory (58.4%), and visual motor speed (52.5%). We observed similar return-to-activity times in the present female cadet cohort relative to the existing female-specific literature. Confidence ranks categorizing post-mTBI performance were heterogenous and indicate multimodal assessments are necessary. Our findings provide clinically relevant insights to female cadets experiencing mTBI across the US service academies for stakeholders providing healthcare.