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.

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.

Female Collegiate Athletes' Concussion Characteristics and Recovery Patterns: A Report from the NCAA-DoD CARE Consortium.

Concussion has been described in the United States (US) collegiate student-athlete population, but female-specific findings are often underrepresented and underreported. Our study aimed to describe female collegiate student-athletes' initial injury characteristics and return to activity outcomes following concussion. Female collegiate student-athletes (n = 1393) from 30-US institutions experienced a concussion and completed standardized, multimodal concussion assessments from pre-injury through unrestricted return to play (uRTP) in this prospective, longitudinal cohort study. Initial injury presentation characteristics, assessment, and return to activity outcomes [<48-h (acute), return to learn, initiate return to play (iRTP), uRTP] were collected. We used descriptive statistics to report injury characteristics, return to activity outcomes, and post-injury assessment performance change categorization (worsened, unchanged, improved) based on change score confidence rank criteria across sport contact classifications [contact (n = 661), limited (n = 446), non-contact (n = 286)]. The median (25th to 75th percentile) days to return to learn was 6.0 (3.0-10.0), iRTP was 8.1 (4.8-13.8), and uRTP was 14.8 (9.9-24.0), but varied by contact classification. Across contact levels, the majority experienced worse SCAT total symptom severity (72.8-82.6%), ImPACT reaction time (91.2-92.6%), and BSI-18 total score (45.2-51.8%) acutely relative to baseline, but unchanged BESS total errors (58.0-60.9%), SAC total score (71.5-76.1%), and remaining ImPACT domains (50.6-66.5%). Our findings provide robust estimates of the typical female collegiate student-athlete presentation and recovery trajectory following concussion, with overall similar findings to the limited female collegiate student-athlete literature. Overall varying confidence rank classification was observed acutely. Our findings provide clinically-relevant insights for athletes, clinicians, researchers, and policymakers to inform efforts specific to females experiencing concussion.

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.

Optimizing Concussion Care Seeking: A Longitudinal Analysis of Recovery.

BACKGROUND: Approximately half of concussions go undisclosed and therefore undiagnosed. Among diagnosed concussions, 51% to 64% receive delayed medical care. Understanding the influence of undiagnosed concussions and delayed medical care would inform medical and education practices. PURPOSE: To compare postconcussion longitudinal clinical outcomes among (1) individuals with no concussion history, all previous concussions diagnosed, and ≥1 previous concussion undiagnosed, as well as (2) those who have delayed versus immediate symptom onset, symptom reporting, and removal from activity after concussion. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Participants included 2758 military academy cadets and intercollegiate athletes diagnosed with concussion in the CARE Consortium. We determined (1) each participant's previous concussion diagnosis status self-reported at baseline (no history, all diagnosed, ≥1 undiagnosed) and (2) whether the participant had delayed or immediate symptom onset, symptom reporting, and removal from activity. We compared symptom severities, cognition, balance, and recovery duration at baseline, 24 to 48 hours, date of asymptomatic status, and date of unrestricted return to activity using tests of parallel profiles. RESULTS: The ≥1 undiagnosed concussion group had higher baseline symptom burdens (P < .001) than the other 2 groups and poorer baseline verbal memory performance (P = .001) than the all diagnosed group; however, they became asymptomatic and returned to activity sooner than those with no history. Cadets/athletes who delayed symptom reporting had higher symptom burdens 24 to 48 hours after injury (mean ± SE; delayed, 28.8 ± 0.8; immediate, 20.6 ± 0.7), took a median difference of 2 days longer to become asymptomatic, and took 3 days longer to return to activity than those who had immediate symptom reporting. For every 30 minutes of continued participation after injury, days to asymptomatic status increased 8.1% (95% CI, 0.3%-16.4%). CONCLUSION: Clinicians should expect that cadets/athletes who delay reporting concussion symptoms will have acutely higher symptom burdens and take 2 days longer to become asymptomatic. Educational messaging should emphasize the clinical benefits of seeking immediate care for concussion-like symptoms.

Optimizing Concussion Care Seeking: The Influence of Previous Concussion Diagnosis Status on Baseline Assessment Outcomes.

BACKGROUND: The prevalence of unreported concussions is high, and undiagnosed concussions can lead to worse postconcussion outcomes. It is not clear how those with a history of undiagnosed concussion perform on subsequent standard concussion baseline assessments. PURPOSE: To determine if previous concussion diagnosis status was associated with outcomes on the standard baseline concussion assessment battery. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Concussion Assessment, Research, and Education (CARE) Consortium participants (N = 29,934) self-reported concussion history with diagnosis status and completed standard baseline concussion assessments, including assessments for symptoms, mental status, balance, and neurocognition. Multiple linear regression models were used to estimate mean differences and 95% CIs among concussion history groups (no concussion history [n = 23,037; 77.0%], all previous concussions diagnosed [n = 5315; 17.8%], ≥1 previous concussions undiagnosed [n = 1582; 5.3%]) at baseline for all outcomes except symptom severity and Brief Symptom Inventory-18 (BSI-18) score, in which negative binomial models were used to calculate incidence rate ratios (IRRs). All models were adjusted for sex, race, ethnicity, sport contact level, and concussion count. Mean differences with 95% CIs excluding 0.00 and at least a small effect size (≥0.20), and those IRRs with 95% CIs excluding 1.00 and at least a small association (IRR, ≥1.10) were considered significant. RESULTS: The ≥1 previous concussions undiagnosed group reported significantly greater symptom severity scores (IRR, ≥1.38) and BSI-18 (IRR, ≥1.31) scores relative to the no concussion history and all previous concussions diagnosed groups. The ≥1 previous concussions undiagnosed group performed significantly worse on 6 neurocognitive assessments while performing better on only 2 compared with the no concussion history and all previous concussions diagnosed groups. There were no between-group differences on mental status or balance assessments. CONCLUSION: An undiagnosed concussion history was associated with worse clinical indicators at future baseline assessments. Individuals reporting ≥1 previous undiagnosed concussions exhibited worse baseline clinical indicators. This may suggest that concussion-related harm may be exacerbated when injuries are not diagnosed.

Neuroendocrine, inflammatory, and extracellular vesicle responses during the Navy Special Warfare Screener Selection Course.

Military operational stress is known to increase adrenal hormones and inflammatory cytokines, while decreasing hormones associated with the anabolic milieu and neuroendocrine system. Less is known about the role of extracellular vesicles (EVs), a form of cell-to-cell communication, in military operational stress and their relationship to circulating hormones. The purpose of this study was to characterize the neuroendocrine, cytokine, and EV response to an intense. 24-h selection course known as the Naval Special Warfare (NSW) Screener and identify associations between EVs and cytokines. Blood samples were collected the morning of and following the NSW Screener in 29 men (18-26 yr). Samples were analyzed for concentrations of cortisol, insulin-like growth factor I (IGF-I), neuropeptide-Y (NPY), brain-derived neurotrophic factor (BDNF), α-klotho, tumor necrosis factor-α (TNFα), and interleukins (IL) -1ß, -6, and -10. EVs stained with markers associated with exosomes (CD63), microvesicles (VAMP3), and apoptotic bodies (THSD1) were characterized using imaging flow cytometry and vesicle flow cytometry. The selection event induced significant changes in circulating BDNF (-43.2%), IGF-I (-24.6%), TNFα (+17.7%), and IL-6 (+13.6%) accompanied by increases in intensities of THSD1+ and VAMP3+ EVs (all P < 0.05). Higher concentrations of IL-1ß and IL-10 were positively associated with THSD1+ EVs (P < 0.05). Military operational stress altered the EV profile. Surface markers associated with apoptotic bodies were positively correlated with an inflammatory response. Future studies should consider a multiomics assessment of EV cargo to discern canonical pathways that may be mediated by EVs during military stress.

Factors Associated with Symptom Reporting in U.S. Service Academy Cadets and NCAA Student Athletes without Concussion: Findings from the CARE Consortium.

BACKGROUND: Symptom resolution is a key marker in determining fitness for return to activity following concussion, but in some cases, distinguishing persistent symptoms due to concussion versus symptoms related to other factors can be challenging. OBJECTIVE: To determine base rates of postconcussional syndrome (PCS) diagnostic categorization in healthy cadets and student athletes with no recent concussion. METHODS: 13,009 cadets and 21,006 student athletes completed baseline preseason testing. After inclusion/exclusion criteria were applied, the final sample included 12,039 cadets [9123 men (75.8%); 2916 women (24.2%)] and 18,548 student athletes [10,192 men (54.9%); 8356 women (45.1%)]. Participants completed the Sport Concussion Assessment Tool-3rd Edition (SCAT3) symptom evaluation as part of baseline preseason testing. The PCS diagnostic categorization was classified by the International Classification of Diseases, 10th Revision (ICD-10) symptom criteria for PCS. RESULTS: In the absence of recent concussion, subgroups of cadets (17.8% of men; 27.6% of women) and student athletes (11.4% of men; 20.0% of women) reported a cluster of symptoms that would meet the ICD-10 symptom criteria for PCS. Participants with insufficient sleep and/or preexisting conditions (e.g., mental health problems), freshmen cadets, and cadets at the U.S. Coast Guard Academy and at the U.S. Air Force Academy (freshmen were tested during basic cadet training) were more likely to report a cluster of symptoms that would meet the ICD-10 symptom criteria for PCS. CONCLUSION: The ICD-10 symptom criteria for PCS can be mimicked by preexisting conditions, insufficient sleep, and/or stress. Findings support person-specific assessment and management of symptoms following concussion.

The examination of mental toughness, sleep, mood and injury rates in an Arctic ultra-marathon.

There is scarcity of research examining the physiological and psychological effects of ultra-endurance racing on athletes in extreme conditions. The purpose of the current study was to identify common injury patterns and illness, profile mood states and sleep patterns and finally examine the relationships between mental toughness, sleep, mood and injury rates during a 120 mile, three-day Arctic ultra-marathon. Twelve participants (3 females, 9 males) with a mean age of 42 ± 5.35 yrs participated in the study. Mental toughness was measured using the MT18 questionnaire. Injuries were clinically assessed and recorded each day. Temperatures ranged from -20 to -6 degrees Celsius throughout the race. Sleep quantity and mood state were recorded using the BRUMS questionnaire. 10 out of the 12 participants experienced injuries; almost half of the participants had injuries that carried over a number of days. Mean sleep duration over the three days was 4.07 h, with an average of 0.78 injuries per day. Significant changes in mood were recorded across the three days, specifically a reduction in vigour (p = .029) and increase in fatigue (p = .014). Neither sleep quantity nor mental toughness was correlated with injury rate. Interestingly, sleep quantity was not related to changes in mood, as previously shown in ultra-marathons. Mental toughness had a moderate negative correlation (p < 0.01) with depression (-.623), reduced anger (-.616), confusion (-.558), increased vigour (.497) and tension (-.420) during the race. Success in this type of event involves significant psychological and physiological preparation to minimize the effects of sleep deprivation and avoidance of injuries.

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.

Estimated age of first exposure to American football and outcome from concussion.

OBJECTIVE: To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion. METHODS: Participants were recruited across 30 colleges and universities as part of the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education Consortium. There were 294 NCAA American football players (age 19 ± 1 years) evaluated 24-48 hours following concussion with valid baseline data and 327 (age 19 ± 1 years) evaluated at the time they were asymptomatic with valid baseline data. Participants sustained a medically diagnosed concussion between baseline testing and postconcussion assessments. Outcome measures included the number of days until asymptomatic, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) composite scores, Balance Error Scoring System (BESS) total score, and Brief Symptom Inventory 18 (BSI-18) subscores. The eAFE was defined as participant's age at the time of assessment minus self-reported number of years playing football. RESULTS: In unadjusted regression models, younger eAFE was associated with lower (worse) ImPACT Visual Motor Speed (R 2 = 0.031, p = 0.012) at 24-48 hours following injury and lower (better) BSI-18 Somatization subscores (R 2 = 0.014, p = 0.038) when the athletes were asymptomatic. The effect sizes were very small. The eAFE was not associated with the number of days until asymptomatic, other ImPACT composite scores, BESS total score, or other BSI-18 subscores. CONCLUSION: Earlier eAFE to American football was not associated with longer symptom recovery, worse balance, worse cognitive performance, or greater psychological distress following concussion. In these NCAA football players, longer duration of exposure to football during childhood and adolescence appears to be unrelated to clinical recovery following concussion.

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.

Investigating the Range of Symptom Endorsement at Initiation of a Graduated Return-to-Play Protocol After Concussion and Duration of the Protocol: A Study From the National Collegiate Athletic Association-Department of Defense Concussion, Assessment, Research, and Education (CARE) Consortium.

BACKGROUND: Organizations recommend that athletes should be asymptomatic or symptom-limited before initiating a graduated return-to-play (GRTP) protocol after sports-related concussion, although asymptomatic or symptom-limited is not well-defined. HYPOTHESES: (1) There will be a range (ie, beyond zero as indicator of "symptom-free") in symptom severity endorsement when athletes are deemed ready to initiate a GRTP protocol. (2) Baseline symptom severity scores and demographic/preinjury medical history factors influence symptom severity scores at the commencement of the GRTP protocol. (3) Greater symptom severity scores at GRTP protocol initiation will result in longer protocol duration. (4) Symptom severity scores will not differ between those who did and did not sustain a repeat injury within 90 days of their initial injury. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Across 30 universities, athletes (N = 1531) completed assessments at baseline and before beginning the GRTP protocol, as determined by local medical staff. Symptom severity scores were recorded with the symptom checklist of the Sport Concussion Assessment Tool-3rd Edition. Nonparametric comparisons were used to examine the effect of medical, demographic, and injury factors on symptom endorsement at GRTP protocol initiation, as well as differences in symptom severity scores between those who did and did not sustain a repeat injury within 90 days. A Cox regression was used to examine the association between symptom severity scores at GRTP protocol initiation and protocol duration. RESULTS: Symptom severity scores at the time when the GRTP protocol was initiated were as follows: 0 to 5 (n = 1378; 90.0%), 6 to 10 (n = 76; 5.0%), 11 to 20 (n = 42; 3.0%), and ≥21 (n = 35; 2.0%). Demographic (sex and age), medical (psychiatric disorders, attention-deficit/hyperactivity disorder, learning disorder), and other factors (baseline symptom endorsement and sleep) were significantly associated with higher symptom severity scores at the GRTP initiation (P < .05). The 4 GRTP initiation time point symptom severity score groups did not significantly differ in total time to unrestricted RTP, χ2(3) = 1.4; P = .73. When days until the initiation of the GRTP protocol was included as a covariate, symptom severity scores between 11 and 20 (P = .02; hazard ratio = 1.44; 95% CI, 1.06-1.96) and ≥21 (P < .001; hazard ratio = 1.88; 95% CI, 1.34-2.63) were significantly associated with a longer GRTP protocol duration as compared with symptom severity scores between 0 and 5. Symptom severity scores at GRTP initiation did not significantly differ between those who sustained a repeat injury within 90 days and those who did not (U = 29,893.5; P = .75). CONCLUSION: A range of symptom severity endorsement was observed at GRTP protocol initiation, with higher endorsement among those with higher baseline symptom endorsement and select demographic and medical history factors. Findings suggest that initiation of a GRTP protocol before an absolute absence of all symptoms is not associated with longer progression of the GRTP protocol, although symptom severity scores >10 were associated with longer duration of a GRTP protocol. Results can be utilized to guide clinicians toward optimal GRTP initiation (ie, balancing active recovery with avoidance of premature return to activity).

Changing Perception: Outcomes from a Physical Medicine and Rehabilitation Medical Student Interest Fair.

Exposure to the field of Physical Medicine and Rehabilitation (PM&R) is limited in the curricula of many medical schools. As a result, many students lack awareness of the field and may therefore ultimately choose different careers. A medical student PM&R career fair was held on October 13th, 2015 at the University of Pittsburgh, and several local medical schools were invited to participate. Seven stations were deployed to highlight various aspects of PM&R careers. A total of 57 medical students attended, representing five different campuses across three states, with 29 of the reported medical students still within their first or second year of medical education. Self-reported interest and understanding of PM&R significantly increased in those attending the fair compared to baseline, with nearly half requesting further opportunities for faculty mentorship. These results indicate that PM&R interest fairs may be a means to further student understanding and awareness of PM&R while providing an opportunity to become more involved in the field.