Previous Concussion Research Articles

The Association Of Pre-season Sleep And Emotional Complaints With Concussion Risk And Symptoms In Adolescents

PURPOSE:This study investigated the associations of baseline sleep and emotional complaints on concussion severity and symptomology in adolescents (10-18 years old). METHODS: Pre-season/baseline concussion assessments were prospectively collected in 626 adolescent participants (age = 15.5 ± 1.7 years). Part of this baseline assessment examined symptoms, including those related to sleep disturbances and emotional complaints. Participants who experienced physician-diagnosed concussion during the season underwent follow up concussions symptom assessments. Linear regressions determined associations between overall concussion symptom scores and 1) baseline drowsiness, 2) baseline emotional symptoms and 3) the combination of both baseline drowsiness and emotional symptoms. Logistic regressions determined associations between all concussion symptoms and baseline drowsiness (Model 1), baseline emotional symptoms (Model 2) and the combination of both baseline drowsiness and emotional symptoms (Model 3). Both the linear and logistic regressions adjusted for age, time from injury, number of previous concussions, loss of memory during most recent concussion and loss of consciousness during most recent concussion. RESULTS: From 292 (15.7 ± 1.7 years) concussions, 174 reported baseline drowsiness and 183 baseline emotional symptoms. Increased concussion symptom scores were associated with both baseline drowsiness and emotional symptoms (unstandardised b [B] > 4.6, p < 0.01, along with a 2.6 (95% CI = 1.9 to 3.6) and 2.8 (95% CI = 2.0 to 3.9) times greater odds of sustaining a concussion, respectively. Sleep and emotional complaints in adolescent athletes are associated with higher risk of adverse clinical outcomes from concussion. CONCLUSIONS: This study indicated sleep problems and emotional disturbances during pre-season can precipitate and exacerbate concussion. As both sleep and emotions are controlled by the limbic system, dysfunction of the limbic system may play an important role in concussion symptom severity. However future research is needed to explore this premise.

Exploring Children’s Experiences Following Sport-Related Concussions

Objectives: To gain a better understanding of the emotional and mental experiences of child and adolescent athletes following a sport-related concussion, in order to better support these athletes throughout recovery.&#x0D; Methods: Adolescents (n=21) ages 15-24 years who self-reported experiencing a sport-related concussion under the age of 18, participated in a retrospective, single group, qualitative analysis based on semi-structured interviews. Thematic Content Analysis was used to identify themes amongst participants’ responses.&#x0D; Results: The results indicated three overarching domains with underlying themes and subthemes within: (1) Acute Challenges Post-Concussion (i.e., difficulty accepting unknowns, self-image and mattering, school, missing out and isolation, feelings of hopelessness), (2) Coping with Acute Challenges Post-Concussion (i.e., support, previous concussions, prioritizing mental health), and (3) Take-Aways Post-Concussion (i.e., learning about injury, self-growth, long lasting impacts on overall health).&#x0D; Conclusion: Child and adolescent athletes face numerous emotional challenges post-concussion and following recovery; however, there are many ways in which children are resilient and cope with these challenges.&#x0D; Implications: It is critical that the knowledge of child and adolescent athletes’ challenges post-concussion, as well as the successful coping mechanisms and protective factors utilized throughout recovery are used to develop better preventative and interventive strategies, in order to support the athletes’ well-being post-concussion.

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.

Multisensory perception is not influenced by previous concussion history in retired rugby union players

ABSTRACT Background To assess whether concussion history adversely affects multisensory integration, we compared susceptibility to the Sound-Induced Flash Illusion (SIFI) in retired professional rugby players compared to controls. Methods Retired professional rugby players ((N = 58) and retired international rowers (N = 26) completed a self-report concussion history questionnaire and the SIFI task. Susceptibility to the SIFI (i.e., perceiving two flashes in response to one flash paired with two beeps) was assessed at three stimulus onset asynchronies (70 ms, 150 ms or 230 ms).Logistic mixed-effects regression modeling was implemented to evaluate how athlete grouping, previous concussion history and total number of years playing sport, impacted the susceptibility to the SIFI task. The statistical significance of a fixed effect of interest was determined by a likelihood ratio test. Results Former rugby players had significantly more self-reported concussions than the rower group (p < 0.001). There was no impact of athlete grouping (i.e., retired professional rugby players and retired international rowers), years participation in elite sport or concussion history on performance in the SIFI. Conclusion A career in professional rugby, concussion history or number of years participating in professional rugby was not found to be predictive of performance on the SIFI task.

Optimizing Concussion Care Seeking: Identification of Factors Predicting Previous Concussion Diagnosis Status.

There is limited understanding of factors affecting concussion diagnosis status using large sample sizes. The study objective was to identify factors that can accurately classify previous concussion diagnosis status among collegiate student-athletes and service academy cadets with concussion history. This retrospective study used support vector machine, Gaussian Naïve Bayes, and decision tree machine learning techniques to identify individual (e.g., sex) and institutional (e.g., academic caliber) factors that accurately classify previous concussion diagnosis status (all diagnosed vs 1+ undiagnosed) among Concussion Assessment, Research, and Education Consortium participants with concussion histories ( n = 7714). Across all classifiers, the factors examined enable >50% classification between previous diagnosed and undiagnosed concussion histories. However, across 20-fold cross validation, ROC-AUC accuracy averaged between 56% and 65% using all factors. Similar performance is achieved considering individual risk factors alone. By contrast, classifications with institutional risk factors typically did not distinguish between those with all concussions diagnosed versus 1+ undiagnosed; average performances using only institutional risk factors were almost always <58%, including confidence intervals for many groups <50%. Participants with more extensive concussion histories were more commonly classified as having one or more of those previous concussions undiagnosed. Although the current study provides preliminary evidence about factors to help classify concussion diagnosis status, more work is needed given the tested models' accuracy. Future work should include a broader set of theoretically indicated factors, at levels ranging from individual behavioral determinants to features of the setting in which the individual was injured.

Long-term effects of multiple concussions on prefrontal cortex oxygenation during repeated squat-stands in retired contact sport athletes

ABSTRACT Background This study investigated the long-term effects of multiple concussions on prefrontal cortex oxygenation using near-infrared spectroscopy (NIRS) during a squat-stand maneuver that activated dynamic cerebral autoregulation. Methods Active male retired contact sport athletes with a history of 3+ concussions (mTBI; n = 55), and active retired athletes with no concussion history (CTRL; n = 29) were recruited. Participants completed a 5-min squat-stand maneuve (10-s squat, 10-s stand, 0.05 Hz; 15 times). Oxygenated (O2Hb), deoxygenated (HHb), total (tHb) hemoglobin, and hemoglobin difference (HbDiff) were analyzed through the change in maximal and minimal values during the test (∆MAX), Z-scores, and standard deviations. Results mTBI group showed left prefrontal cortex O2Hb ∆MAX (p = 0.046) and HbDiff ∆MAX (p = 0.018) were significantly higher. Within-group analyses showed significantly higher left HHb ∆MAX (p = 0.003) and lower left HbDiff Z-scores (p = 0.010) only in the mTBI group. The CTRL group demonstrated significantly lower left HbDiff SD (p = 0.039), tHb Z-scores (p = 0.030), and HbDiff ∆MAX (p = 0.037) compared to right prefrontal cortex response. Conclusion These preliminary results suggest changes in prefrontal cortex oxygenation potentially affecting the brain’s ability to adapt to changing cerebral perfusion pressure after multiple previous concussions.

Injury Characteristics Among Pediatric Athletes Who did and did not Undergo a CT Scan Following Concussion

Background:CDC and AAP guidelines discourage routine neuroimaging following concussion, as CT scans are only indicated if severe intracranial injury is suspected. Validated prediction rules such as Pediatric Emergency Care Applied Research Network (PECARN) criteria have decreased the number of unnecessary pediatric head CTs; however, are still commonly performed following pediatric sport-related concussion (SRC).Hypothesis/Purpose:To determine differences in injury characteristics and outcomes in athletes who did and did not undergo head CT following SRC.Methods:Data were prospectively collected from participants enrolled in the North Texas Concussion Network Registry (ConTex) between August 2015-May 2021. Participants aged 5-18 diagnosed with SRC and presenting within 30 days were included. Participants were separated into 2 groups based on whether they had a CT scan following SRC: CT (negative scan) and no CT. Positive CTs were excluded. Groups were matched in age and time to presentation (≤14, >14-30 days). Demographics, concussion-related details, and 3-month outcome variables were analyzed including days to symptom resolution (≤30 vs >30 days) and return-to-play (RTP).Results:324 participants were included: 162 in each group. There were no significant differences between the groups in sex, race, ethnicity, or previous concussion history. Differences in injury-related characteristics are reported in Table 1. Participants in the CT group were more likely to be participating in unorganized events (p=0.05), and less likely to continue playing following SRC (p=0.003) than the no CT group. The CT group more frequently reported head to surface mechanism of injury than the no CT group. Significantly higher rates of loss of consciousness (LOC), amnesia, and vomiting following SRC were reported in the CT group. At 3-months post-SRC, the no CT group reported RTP a week sooner than the CT group (28.8±22.3 vs 35.7±27.3 days, p=0.019). However, there was no difference in prolonged recovery (>30 days: 29.6 vs 40.5%, p=0.07) or overall RTP rates (91.9 vs 85.8%, p=0.09) between the no CT and CT groups.Conclusion:Pediatric athletes who underwent CT following SRC exhibited significantly different injury-related characteristics compared to those who did not, but the differences observed did not impact symptom resolution or return-to-play. While LOC and vomiting differences align with the PECARN prediction rules and likely contribute to decision to perform CT, the additional differences of participating in an unorganized event, head-to-surface impact, and amnesia are not part of PECARN criteria. Further research is needed to discover which variables may contribute to unnecessary head CTs following SRC.Table 1.Injury related characteristics between the CT and no CT scan groups

Neck strength and concussion prevalence in football and rugby athletes

ObjectivesTo determine the maximal isometric neck strength of male and female rugby and football (soccer) athletes, and to investigate the relationship between neck strength and sport played, sex, age, anthropometric measurements and concussion history. DesignCross-sectional observational study. MethodsIn total, 358 (70% male) healthy football and rugby playing adolescents and adults participated. Isometric neck strength and anthropometry measurements were collected, as well as completion of a sociodemographic survey. The mean (standard deviation) of all measurements for each age group was calculated and compared between sports and sexes, with correlation analyses performed to determine associations between all variables. ResultsIn general, rugby athletes had stronger neck musculature compared to football athletes, and males had stronger neck musculature compared to age-matched females, with these strength differences becoming increasingly significant with age (p < 0.05). The athletes with stronger neck muscles were older, taller, heavier, had higher bilateral grip strength and larger neck girth compared to those with weaker neck muscles (p < 0.05). Male rugby athletes who self-reported higher rates of a previous concussion had lower neck flexor/extensor strength ratio (p < 0.01). In 11–12-year-old male footballers, increased heading was associated with increased self-reported previous concussion (p < 0.01). ConclusionsThese normative neck strength data can form important reference values for rugby and football athletes from adolescence into adulthood. Male rugby athletes with a previous history of concussion demonstrated strength imbalances of their neck musculature (lower flexor/extensor ratio), with this finding having potentially important implications for training protocols and injury prevention initiatives.

Concussion Knowledge, Attitudes, and Reporting Behaviors of Sports Car Racing Drivers

ABSTRACT Purpose Optimal concussion management includes early recognition, immediate removal from competition, and diagnosis of concussion. However, because of varied medical access, concussion detection in the automobile racing is challenging, warranting further investigation into concussion knowledge, attitudes, and reporting behaviors. Therefore, the present investigation aimed to characterize concussion knowledge, attitudes, and report behaviors in the specialized motorsport format of “sports car racing.” Methods A total of 59 racing drivers participating in the Pirelli World Challenge racing series completed a cross-sectional paper-and-pencil survey. Scores for symptom recognition, knowledge, and attitudes of concussion, and describe reporting behaviors were reported. Results Drivers commonly recognized confusion (94.4%), headache (92.6%), loss of consciousness (90.7%), and blurred vision (88.9%) as signs of concussion. Sleep problems were the least recognized (48.2%) symptom. Total knowledge score averaged 34.65 ± 4.7 out of 42, and total attitude score was 45.11 ± 3.5 out of 49. Over half of drivers (55.2%) who recalled a racing-related concussion indicated that they reported all their concussions to a medical professional or teammate. The most common reasons for reporting a concussion included they did not want to have any further damage to their brain (31.0%), they thought that they had a concussion (20.7%), and they were scared (13.7%); common reasons for nondisclosure included not wanting to let their team down (15.4%) and not thinking it was serious (15.4%). Conclusions Drivers correctly identified common concussion signs and symptoms, and had favorable concussion knowledge and attitudes. Over half of drivers who recalled a previous driving-related concussion indicated that they reported their injury to a medical professional or teammate. The application of the present investigation will inform the health care team working at racing events to help manage concussions.

472 Effects of Recurrent Mild Traumatic Brain Injuries on Incidence, Severity, and Recovery of Concussion in Young Student-Athletes

INTRODUCTION: Currently, it is known that athletes who sustain recurrent concussions are at an increased risk for long-term neurological consequences. Moreover, in the short term, athletes with a history of concussions are significantly more likely to sustain future concussions. Although the increased incidence of mTBI among athletes with a history of concussions has been well documented, there is less consensus about how recurrent concussions affect the severity and recovery of the next head trauma. METHODS: Data from 11 563 ImPACT baseline evaluations of US student-athletes aged 12 to 22 years were separated into 2 cohorts: subjects reporting 2 or more previous concussions (PC; n = 976 baseline evaluations) at baseline and a control group reporting zero previous concussions (CT; n = 7743 baseline evaluations). Subjects reporting 1 prior concussion were excluded. Differences in SND incidence, severity, and recovery between the 2 cohorts were assessed using chi-squared tests, t tests, survival analyses, and multivariate regressions. RESULTS: The PC cohort had a higher incidence of head injury leading to ImPACT (436.7 per 1000 person-years vs 194.4 per 1000 person-years, P &lt; .0001) and a higher incidence of SND (140.4 vs 71.8, P &lt; .0001) than controls. However, the Severity Index (SI) demonstrated that SND severity was lower in the PC group (7.55 vs 8.59, P = .04). Adjusted analyses similarly demonstrated that the PC cohort had increased SND incidence (odds ratio = 1.93; 95% CI, 1.61 to 2.31; P &lt; .0001), decreased SI (β = −1.37; 95% CI, −2.40 to −0.34; P = .009), and equivalent recovery (hazard ratio = 0.98; 95% CI, 0.76 to 1.72; P = .90). CONCLUSION: Participants with a history of concussion have a higher incidence of SND but present with lower severity SND, which may be a result of increased concussion education or symptom awareness. Recurrent concussion has no significant impact on acute neurocognitive recovery. Together, these results provide evidence against the supposition that a history of concussion increases the severity of future SND.

Examining the Relationship Between Mild Traumatic Brain Injuries and Development of Mental Illness Disorders in a Mid-Term Follow-up Period.

The sequalae of mild concussions continue to emerge with increased awareness in sports-related injuries. This study aimed to quantify the number of patients who are affected by a mental illness within 3 yrs of a concussion and identify whether demographic differences exist that may influence a mental illness diagnosis. Using a nationwide database, data were queried for a diagnosis of concussion, capturing patients aged 18-45 yrs with no previous mental illness, and then identified if these patients were diagnosed with a mental illness within 3 yrs of their concussion. The mental illnesses specifically chosen for this study included depression, anxiety, panic disorder, posttraumatic stress disorder, bipolar, and schizophrenia. Within 3 yrs after a concussion, 48% of patients were later diagnosed with a mental illness. All of the mental illnesses this study chose to evaluate were present in a higher proportion of patients after a concussion than the general population. The mechanism between concussions and mental illness remains unclear. A large proportion of patients who experience a concussion are later diagnosed with a mental illness within 3 yrs. Patients with a history of a previous concussion may benefit from screening for the development of a mental illness.

The Effect of Sex, Sport, and Preexisting Histories on Baseline Concussion Test Performance in College Lacrosse and Soccer Athletes.

To study sex and sport differences in baseline clinical concussion assessments. A secondary purpose was to determine if these same assessments are affected by self-reported histories of (1) concussion; (2) learning disability; (3) anxiety and/or depression; and (4) migraine. Prospective cohort. National Collegiate Athletic Association D1 Universities. Male and female soccer and lacrosse athletes (n = 237; age = 19.8 ± 1.3 years). Sport, sex, history of (1) concussion; (2) learning disability; (3) anxiety and/or depression; and (4) migraine. Sport Concussion Assessment Tool 22-item symptom checklist, Standardized Assessment of Concussion, Balance Error Scoring System (BESS), Generalized Anxiety Disorder 7-item scale, and Patient Health Questionnaire. Female athletes had significantly higher total symptoms endorsed (P = 0.02), total symptom severity (P < 0.001), and BESS total errors (P = 0.01) than male athletes. No other sex, sport, or sex-by-sport interactions were observed (P > 0.05). Previous concussion and migraine history were related to greater total symptoms endorsed (concussion: P = 0.03; migraine: P = 0.01) and total symptom severity (concussion: P = 0.04; migraine: P = 0.02). Athletes with a migraine history also self-reported higher anxiety (P = 0.004) and depression (P = 0.01) scores. No other associations between preexisting histories and clinical concussion outcomes were observed (P > 0.05). Our findings reinforce the need to individualize concussion assessment and management. This is highlighted by the findings involving sex differences and preexisting concussion and migraine histories. Clinicians should fully inventory athletes' personal and medical histories to better understand variability in measures, which may be used to inform return-to-participation decisions following injury.

Previous concussions increase the risk of mental health disability in college athletes

Mental health concerns, particularly anxiety and depression, are leading causes of disability in young adults. Identifying pre-existing conditions that place individuals at-risk for mental health disability may enable healthcare providers to increase patient outcomes with early interventions and condition management. Read more JCTRes.com

Collision avoidance strategies between two athlete walkers: Understanding impaired avoidance behaviours in athletes with a previous concussion

BackgroundIndividuals who have sustained a concussion often display associated balance control deficits and visuomotor impairments despite being cleared by a physician to return to sport. Such visuomotor impairments can be highlighted in collision avoidance tasks that involves a mutual adaptation between two walkers. However, studies have yet to challenged athletes with a previous concussion during an everyday collision avoidance task, following return to sport. Research QuestionDo athletes with a previous concussion display associated behavioural changes during a 90°-collision avoidance task with an approaching pedestrian? MethodsThirteen athletes (ATH; 9 females, 23 ± 4years) and 13 athletes with a previous concussion (CONC; 9 females, 22 ± 3 years, concussion <6 months) walked at a comfortable walking speed along a 12.6 m pathway while avoiding another athlete on a 90º-collision course. Each participant randomly interacted with individuals from the same group 20 times and interacted with individuals from the opposite group 21 times. Minimum predicted distance (mpd) was used to examine collision avoidance behaviours between ATH and CONC groups. ResultsThe overall progression of mpd(t) did not differ between groups (p > .05). During the collision avoidance task, previously concussed athletes contributed less when passing second compared to their peers(p < .001). When two previously concussed athletes were on a collision course, there was a greater amount of variability resulting in inappropriate adaptive behaviours. SignificanceAlthough successful at avoiding a collision with an approaching athlete, previously concussed athletes exhibit behavioural changes manifesting in riskier behaviours. The current findings suggest that previously concussed athletes possess behavioural changes even after being cleared to returned to sport, which may increase their risk of a subsequent injury when playing.

Concussion-related Alterations in Neural Activity During Emotion Recognition: Case Studies of Short-term and Residual Effects

Concussions have recently become an area of concern among the general public, but a clear understanding of their total consequence is still being developed. Symptoms of concussions are wide-ranging, encapsulating a plethora of cognitive and emotional abilities that could be affected. Concussions transiently disrupt neural activation as well as behavioral responses across multiple categories. Skills pertaining to various aspects of emotions are often affected yet have rarely been studied after concussions. We present two case studies of collegiate athletes with a history of multiple concussions. This paper highlights the case of a collegiate athlete who had obtained two previous concussions with the most recent being sustained sixteen days prior to neuroimaging. A second athlete with two lifetime concussions was tested one year after the most recent injury. The current study utilized a novel emotional recognition task to assess the behavioral and neural effects of this injury. A group of five controls responded with high accuracy rates and quick response times to the task. They showed activation in regions of the frontal lobe as well as facial recognition areas of the occipital lobe. The 16-day case subject was impaired in recognizing emotions relative to controls and showed little to no overlap in brain activity for regions involved in emotional face processing. The athlete with a longer post-concussion period also showed residual effects of neural activity alteration when compared to controls with few overlapping active regions. Specific brain regions were activated in this group but not in controls including the sensorimotor cortex, supramarginal gyrus, and lateral occipital cortex. By taking a more individual approach in examination of neural activity post-concussion, we may be able to gain a better understanding of this heterogeneous injury.

Treatment Decisions in Pediatric Sports Medicine: Do Personal and Professional Bias Affect Decision-Making?

Background:Personal and professional biases can affect decision-making regarding important issues in pediatric sports medicine. Gaining insight into the opinions of health care professionals who specialize in pediatric sports medicine will provide information that may be useful for directing ongoing research in this field.Hypothesis:It was hypothesized that surgeons would demonstrate bias toward early surgical intervention versus nonsurgeons. In addition, it was hypothesized that youth sports medicine professionals who were parents of a child with a previous major sports injury or concussion would be less likely to allow their child to play American tackle football or return to football after a concussion.Study Design:Cross-sectional study.Methods:An online survey was provided to the active members of the Pediatric Research in Sports Medicine Society. We used both professional background information and responses to questions related to personal experiences with youth sports injuries to determine potential factors associated with underlying biases. Survey responses among subgroups were compared using the Fisher exact test. The Pearson correlation coefficient was used to evaluate years in practice versus opioid use.Results:Of the survey participants, 62.5% were pediatric surgeons, and 37.5% represented different nonsurgical youth sports medicine professions. Surgeons were less likely than nonsurgeons to agree to allow their child to return to football after sustaining a concussion and completing a concussion protocol (48% vs 76%, P = .013). Surgeons were more likely than nonsurgeons to agree to both elective shoulder stabilization after a first-time dislocation and elective drilling of a stable knee osteochondritis dissecans (OCD) before nonoperative treatment (41% vs 10%, P = .003 and 52% vs 23%, P = .013, respectively). Those who reported having a child with a concussion history were more likely to support him or her returning to football after a concussion (65% vs 33%, P = .026).Conclusion:Surgeons were more likely to favor elective shoulder-stabilization surgery after a first-time dislocation and drilling of a stable knee OCD instead of nonoperative management. Personal experience of having a child who sustained a major sports injury or concussion did not demonstrate a bias against participation in football or return to football after a concussion.

Head Impact Exposure in American High School Football and Ice Hockey: A Longitudinal Prospective Cohort Study

<h3>Research Objectives</h3> To prospectively investigate the relationship between head impact (HI) exposure, neuropsychological performance, and reported symptoms in youth football and ice hockey players in the United States. We hypothesized that exposure to greater linear and rotational forces would be associated with neuropsychological inefficiency and increased symptoms. <h3>Design</h3> Longitudinal prospective cohort over the course of one year. <h3>Setting</h3> General community. <h3>Participants</h3> Volunteer sample comprised of male student-athletes with current or planned participation in American football or ice hockey who were within 90 days of starting 10th or 11th grades (N=34). Those who had significant developmental, academic, or neurologic history or did not complete one year follow up (n=9) were excluded. <h3>Interventions</h3> Not applicable. <h3>Main Outcome Measures</h3> Linear and rotational acceleration/deceleration forces were measured via helmet sensors (football) and mouth guards (ice hockey). Participant background (past medical history of specific learning disorder, attention disorder, mood or anxiety disorder, or headache/migraine), neuropsychological testing (ImPACT, paper/pencil measures), concussion history, and symptom report (PCSS) were gathered during preseason (PS) and at one year follow up (FU). Neuropsychological inefficiency (NPI, Beauchamp, 2015) at FU and change in total reported symptoms were calculated. <h3>Results</h3> Participant background and previous concussion were associated with increased odds of NPI (all odds ratios=5.57-15.76, all ps=0.24-0.27) and symptom increase at FU (all OR=1.56-5.57, all p=0.26-0.85), albeit none were statistically significant. No significant associations were observed for HI exposure variables. <h3>Conclusions</h3> In this pilot study, we did not observe statistically significant associations between HI exposure and neuropsychological inefficiency or increased symptoms at one year follow up. Larger studies with a broader participant pool (e.g., additional contact sports, females) and longer-term follow-up are warranted to corroborate these findings. If the present findings are substantiated, results would support safe participation in contact sports. <h3>Author(s) Disclosures</h3> None.

Understanding the Characteristics of High-Cost Healthcare Users in a Persistent Concussion Clinic for Youth

<h3>Research Objectives</h3> To investigate the predictors of those with high healthcare costs in a Pediatric Persistent Concussion Clinic. <h3>Design</h3> Cohort study. <h3>Setting</h3> A specialty outpatient clinic in a children's rehabilitation hospital in Toronto, Canada. These services included occupational therapy, physical therapy, social work, and/or neuropsychology. <h3>Participants</h3> A referred sample of 461 youth that had been experiencing post-concussion symptoms for at least 4 weeks. Youth were between 3 to 18 years. 47.4% were male and 53.6% were female. <h3>Interventions</h3> Not applicable. <h3>Main Outcome Measures</h3> Total direct healthcare costs from the Persistent Concussion Clinic. Clients whose total direct healthcare costs were above the 80th percentile ($1655.48) were classified as high-cost users. <h3>Results</h3> Four logistic regressions were conducted and compared to each other using likelihood ratio tests. Each model contained variables from the previous model along with an additional group of variables. Variable selection was determined based on previous conceptual frameworks for predicting high-cost users of healthcare systems. Model 1: Demographic Characteristics (age, sex). Model 2: Medical History (psychiatric history, number of previous concussions, history of therapy). Model 3: Symptom Severity (number of symptoms, symptom duration). Model 4: Service Utilization (number of services used, being prescribed new medication). Model 4 revealed clinically significant effect sizes (i.e., OR > 2). Being prescribed new medication, b = 1.13, p < .001, OR = 3.096 (95% CI: 1.634, 6.027) and the number of services utilized, b = 1.55, p < .001, OR = 4.731 (95% CI: 3.368, 7.011) were found to be significant predictors. A likelihood ratio test shows that this model performs significantly better than the logistic regression without service utilization variables, χ2(2) = 154.2, p < .001. <h3>Conclusions</h3> Service utilization is a significant predictor of high-cost users. Future research should incorporate this information into a prediction algorithm, whereby early service utilization patterns may inform us as to who will have higher healthcare costs. <h3>Author(s) Disclosures</h3> The authors have no conflicts of interest to declare.

The Association Between Concussion History and Increased Symptom Severity Reporting Is Independent of Common Medical Comorbidities, Personality Factors, and Sleep Quality in Collegiate Athletes.

We investigated the degree to which the association between history of concussion with psychological distress and general symptom severity is independent of several factors commonly associated with elevated symptom severity. We also examined whether symptom severity endorsement was associated with concussion injury specifically or response to injury in general. Academic medical center. Collegiate athletes ( N = 106; age: M = 21.37 ± 1.69 years; 33 female) were enrolled on the basis of strict medical/psychiatric exclusion criteria. Cross-sectional single-visit study. Comprehensive assessment, including semistructured interviews to retrospectively diagnose the number of previous concussions, was completed. Single-predictor and stepwise regression models were fit to examine the predictive value of prior concussion and orthopedic injuries on symptom severity, both individually and controlling for confounding factors. Psychological distress was operationalized as Brief Symptom Inventory-18 Global Severity Index (BSI-GSI) ratings; concussion-related symptom severity was measured using the Sport Concussion Assessment Tool. Controlling for baseline factors associated with the symptom outcomes (agreeableness, neuroticism, negative emotionality, and sleep quality), concussion history was significantly associated with psychological distress ( B = 1.25 [0.55]; P = .025, Δ R2 = 0.034) and concussion-like symptom severity ( B = 0.22 [0.08]; P = .005, Δ R2 = 0.064) and accounted for a statistically significant amount of unique variance in symptom outcomes. Orthopedic injury history was not individually predictive of psychological distress ( B = -0.06 [0.53]; P = .905) or general symptom severity ( B = 0.06 [0.08]; P = .427) and did not explain the relationship between concussion history and symptom outcomes. Concussion history is associated with subtle elevations in symptom severity in collegiate-aged athletes; this relationship is independent of medical, lifestyle (ie, sleep), and personality factors. Furthermore, this relationship is associated with brain injury (ie, concussion) and is not a general response to injury history.

Identifying Factors Associated with Head Impact Kinematics and Brain Strain in High School American Football via Instrumented Mouthguards.

Repeated head impact exposure and concussions are common in American football. Identifying the factors associated with high magnitude impacts aids in informing sport policy changes, improvements to protective equipment, and better understanding of the brain's response to mechanical loading. Recently, the Stanford Instrumented Mouthguard (MiG2.0) has seen several improvements in its accuracy in measuring head kinematics and its ability to correctly differentiate between true head impact events and false positives. Using this device, the present study sought to identify factors (e.g., player position, helmet model, direction of head acceleration, etc.) that are associated with head impact kinematics and brain strain in high school American football athletes. 116 athletes were monitored over a total of 888 athlete exposures. 602 total impacts were captured and verified by the MiG2.0's validated impact detection algorithm. Peak values of linear acceleration, angular velocity, and angular acceleration were obtained from the mouthguard kinematics. The kinematics were also entered into a previously developed finite element model of the human brain to compute the 95th percentile maximum principal strain. Overall, impacts were (mean ± SD) 34.0 ± 24.3 g for peak linear acceleration, 22.2 ± 15.4 rad/s for peak angular velocity, 2979.4 ± 3030.4 rad/s2 for peak angular acceleration, and 0.262 ± 0.241 for 95th percentile maximum principal strain. Statistical analyses revealed that impacts resulting in Forward head accelerations had higher magnitudes of peak kinematics and brain strain than Lateral or Rearward impacts and that athletes in skill positions sustained impacts of greater magnitude than athletes in line positions. 95th percentile maximum principal strain was significantly lower in the observed cohort of high school football athletes than previous reports of collegiate football athletes. No differences in impact magnitude were observed in athletes with or without previous concussion history, in athletes wearing different helmet models, or in junior varsity or varsity athletes. This study presents novel information on head acceleration events and their resulting brain strain in high school American football from our advanced, validated method of measuring head kinematics via instrumented mouthguard technology.