Diagnosis Of Sports-related Concussion Research Articles

Pupillary Light Reflex Metrics Differ in Adolescents with Acute Concussion VS. Persistent Post-Concussion Symptoms

Background: A potential objective measure that may assist in identifying vision disorders after concussion is the pupillary light reflex (PLR), which is under autonomic control and contributes to normal convergence and accommodative function which is altered after concussion. This study sought to compare pupillometry measures in adolescents with concussion initially presenting for care in the early acute time frame (≤ 2 weeks post-concussion) to those presenting in the later acute time frame (4 ± 1 weeks). Hypothesis: To determine whether PLR metrics are similar or different between athletes with concussion presenting earlier (≤ 2 weeks post-concussion) for care vs. those presenting later for care (4 ± 1 weeks). Methods: Athletes, ages 12-18 years, with a diagnosis of sport-related concussion (n = 110) were recruited. 89 concussed subjects had their PLR assessment performed at an early acute time point ≤ 2 weeks after concussion, while 21 concussed subjects had their first assessment at a later acute time point (4 week±1 week). Pupillary dynamics were measured in response to a brief, step-input, white light stimulus (154 ms duration; 180 micro watts power) via a Neuroptics PLR-3000 hand-held, infrared, automated, monocular pupillometer (Neuroptics, Irvine, CA). The means of the PLR metrics were compared between groups with one-way Student’s t test. Bonferroni correction was applied. Results: The baseline pupil diameter (mean ± SD) was significantly larger (p<0.05) for the subjects seen later 4 ± 1 week (5.09 mm ± 0.63) as compared to the cohort of subjects who presented earlier within 2 weeks after injury (4.72 ± 0.79mm). Average constriction velocity ACV for the later-presenting cohort (3.35±0.45 mm/s) was significantly faster compared to the early-presenting cohort (3.04±0.59 mm/s). Similarly, maximum constriction velocity for the groups were significantly different (early 4.82±0.90 versus late 5.31±0.70 mm/s), even after Bonferroni correction (p<0.05), with alpha of 0.025. All the other pupillometric parameters were not different from each other. Conclusion: When comparing adolescents with concussion presenting early in the acute phase ≤ 2 weeks after concussion to those presenting later in the acute timeframe to care 4±1 weeks, those presenting later demonstrate enhancement of certain PLR metrics, namely larger baseline pupil diameter and faster average constriction velocity (ACV) and maximum constriction velocity (MCV). Differences in these PLR metrics in those presenting later in the acute timeframe may represent findings in those who are more likely to have persisting post-concussion symptoms, potentially shedding light on pathophysiological underpinnings of lingering symptoms.

The Impact of Concussion, Sport, and Time in Season on Saliva Telomere Length in Healthy Athletes.

To date, sport-related concussion diagnosis and management is primarily based on subjective clinical tests in the absence of validated biomarkers. A major obstacle to clinical validation and application is a lack of studies exploring potential biomarkers in non-injured populations. This cross-sectional study examined the associations between saliva telomere length (TL) and multiple confounding variables in a healthy university athlete population. One hundred eighty-three (108 male and 75 female) uninjured varsity athletes were recruited to the study and provided saliva samples at either pre- or mid-season, for TL analysis. Multiple linear regression was used to determine the associations between saliva TL and history of concussion, sport contact type, time in season (pre vs. mid-season collection), age, and sex. Results showed no significant associations between TL and history of concussion, age, or sport contact type. However, TL from samples collected mid-season were longer than those collected pre-season [β = 231.4, 95% CI (61.9, 401.0), p = 0.008], and males had longer TL than females [β = 284.8, 95% CI (111.5, 458.2), p = 0.001] when adjusting for all other variables in the model. These findings population suggest that multiple variables may influence TL. Future studies should consider these confounders when evaluating saliva TL as a plausible fluid biomarker for SRC.

Rates of false positive outcomes on the A-WPTAS picture items in a sample of non-concussed athletes

ABSTRACT Accurate diagnosis of sports related concussion ensures that athletes are removed from play if concussed and prevents incorrect removal when a concussion has not occurred. Although various screening tools are currently in use, there is no gold standard measure with which to diagnose sports related concussion. Objective: The current study aimed to investigate the diagnostic accuracy of the Abbreviated Westmead Post Traumatic Amnesia Scale (A-WPTAS) picture task, a neurocognitive measure used to assess mild traumatic brain injury. The incidence of false positive classifications and the potential confounding effect of exercise on scores on the A-WPTAS picture items were examined. Methods: The study included an athlete group comprising 33 players and a control group comprising 37 subjects. The A-WPTAS picture task was completed on three testing occasions, separated by three week intervals. Results: Results revealed that the A-WPTAS picture task was highly accurate (>95%) in correctly classifying participants with no concussion across all three testing occasions. There was no significant difference between the two groups in relation to false positive outcomes on any testing occasion, suggesting that exercise was not a confounding factor. Conclusions: Findings provide preliminary evidence to support the use of the A-WPTAS picture task in a sporting context

Utility of Pupillary Light Reflex Metrics as a Physiologic Biomarker for Adolescent Sport-Related Concussion

Concussion diagnosis remains clinical, without objective diagnostic tests available for adolescents. Known deficits in visual accommodation and autonomic function after concussion make the pupillary light reflex (PLR) a promising target as an objective physiological biomarker for concussion. To determine the potential utility of PLR metrics as physiological biomarkers for concussion. Prospective cohort of adolescent athletes between ages 12 and 18 years recruited between August 1, 2017, and December 31, 2018. The study took place at a specialty concussion program and private suburban high school and included healthy control individuals (n = 134) and athletes with a diagnosis of sport-related concussion (SRC) (n = 98). Analysis was completed June 30, 2020. Sports-related concussion and pupillometry assessments. Pupillary light reflex metrics (maximum and minimum pupillary diameter, peak and average constriction/dilation velocity, percentage constriction, and time to 75% pupillary redilation [T75]). Pupillary light reflex metrics of 134 healthy control individuals and 98 athletes with concussion were obtained a median of 12.0 days following injury (interquartile range [IQR], 5.0-18.0 days). Eight of 9 metrics were significantly greater among athletes with concussion after Bonferroni correction (maximum pupil diameter: 4.83 mm vs 4.01 mm; difference, 0.82; 99.44% CI, 0.53-1.11; minimum pupil diameter: 2.96 mm vs 2.63 mm; difference, 0.33; 99.4% CI, 0.18-0.48; percentage constriction: 38.23% vs 33.66%; difference, 4.57; 99.4% CI, 2.60-6.55; average constriction velocity: 3.08 mm/s vs 2.50 mm/s; difference, 0.58; 99.4% CI, 0.36-0.81; peak constriction velocity: 4.88 mm/s vs 3.91 mm/s; difference, 0.97; 99.4% CI, 0.63-1.31; average dilation velocity, 1.32 mm/s vs 1.22 mm/s; difference, 0.10; 99.4% CI, 0.00-0.20; peak dilation velocity: 1.83 mm/s vs 1.64 mm/s; difference, 0.19; 99.4% CI, 0.07-0.32; and T75: 1.81 seconds vs 1.51 seconds; difference, 0.30; 0.10-0.51). In exploratory analyses, sex-based differences were observed, with girls with concussion exhibiting longer T75 (1.96 seconds vs 1.63 seconds; difference, 0.33; 99.4% CI, 0.02-0.65). Among healthy control individuals, diminished PLR metrics (eg, smaller maximum pupil size 3.81 mm vs 4.22 mm; difference, -0.41; 99.4% CI, -0.77 to 0.05) were observed after exercise. These findings suggest that enhancement of PLR metrics characterize acute adolescent concussion, while exercise produced smaller pupil sizes and overall slowing of PLR metrics, presumably associated with fatigue. Quantifiable measures of the PLR may serve in the future as objective physiologic biomarkers for concussion in the adolescent athlete.

Behavioral Tackling Interventions Decrease Head Impact Frequency in American Football Players: A Critically Appraised Topic

Context: The rate of sport-related concussion diagnosis has significantly increased in recent years, which has created a need for injury prevention initiatives. There have been efforts put forth by researchers and American football organizations to teach athletes how to tackle properly in order to decrease the number of subconcussive head impacts and concussions. Clinical Question: Does the implementation of a behavioral tackling intervention decrease the head impact frequency in American football players? Clinical Bottom Line: There is moderate SORT Level B evidence to support the use of behavioral tackling interventions as a means for reducing head impact frequency in football athletes. All four included studies found a significant reduction in head impacts following a behavioral tackling intervention with study findings ranging from a 26–33% reduction in impact frequency. These findings were consistent in youth, high school, and college football players and for different types of behavioral tackling interventions. Therefore, these results indicate that behavioral tackling interventions have the potential to reduce the number of head impacts sustained by American football players, which may ultimately lead to a reduction in concussion occurrence as well.

Neuropsychological test performance in depressed and nondepressed collegiate athletes following concussion.

To examine neuropsychological test differences following concussion between collegiate athletes screening positive and negative for depression. Participants included 113 (91 male) college athletes, who were assessed at baseline and following diagnosis of sport-related concussion (SRC). The Beck Depression Inventory-Fast Screen was used as a screener for depression. Athletes were categorized as either depressed (≥4) or nondepressed (<4) following injury and compared on composites for memory and attention-processing speed. Groups were also compared on reliable change index scores from baseline, as well as on proportion of impaired scores. Depressed athletes performed significantly worse than did nondepressed athletes on the Memory Composite (p = .04, d = .51) but not on the Attention-Processing Speed Composite score (p = .15, d = .46). Chi-square tests indicated that, compared with nondepressed athletes, a significantly higher number of depressed athletes showed reliable decreases on the following test indices: Verbal Memory Composite of the Immediate Post-Concussion Assessment and Cognitive Testing (p = .03, φ = .21), Brief Visuospatial Memory Test-Revised Total (p = .02, φ = .22), and Hopkins Verbal Learning Test-Revised Total (p = .05, φ = .19). Chi-square test indicated that, compared with nondepressed athletes, a significantly higher proportion of depressed athletes met criteria for impairment (p = .02, φ = .23). Whether examining the data at the intraindividual or group level, there are memory deficits associated with the combination of an SRC and depression. The results highlight the importance of screening for depression to provide a more complete picture of an individual's functioning postconcussion. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Reliability and practical clinical application of an accelerometer-based dual-task gait balance control assessment

BackgroundGait balance control assessment using whole body center of mass (COM) kinematic measures in concussed individuals reveals persistent balance deficits up to two months post-injury. A reliable and clinically practical gait balance control assessment leveraging similar kinematic measures is necessary to improve concussion assessment and management. Research questionCan peak accelerations collected during a dual-task (DT) gait assessment from a single low back placed accelerometer be measured reliably on different days, by different raters, in different environments, and be practically applied in a Division One (D1) athletics program? MethodsA single accelerometer placed on the low back over the L5 vertebra was utilized with a DT gait analysis protocol. Twenty (10 F) healthy participants performed the assessment in a laboratory and non-laboratory environment, on two separate days, and with two different raters. Eight gait event specific peak accelerations along three orthogonal axes were collected. In addition, data were collected from a cohort of 14 D1 female soccer players during a single assessment to explore the practical clinical application. ResultsCronbach’s α values for the eight metrics ranged from 0.881 to 0.980 and ICC values from 0.868 to 0.987. Average assessment time for the 14 D1 female athletes was 8.50 ± 0.58 min, and significant differences between walking conditions were identified for Vert Accel 1 (p < .01), Vert Accel 2 (p = .01), and A-P Accel (p < .01). SignificanceHigh Cronbach’s α and ICC values coupled with a short assessment time and sensitivity to differences in gait balance control indicate our testing apparatus and protocol are both reliable and clinically practical. Additionally, gait event specific peak accelerations from a single accelerometer can detect subtle changes in gait balance control and may facilitate improvements in sport-related concussion diagnosis and return to activity decision making.

International consensus definitions of video signs of concussion in professional sports

BackgroundThe use of video to assist professional sporting bodies with the diagnosis of sport-related concussion (SRC) has been well established; however, there has been little consistency across sporting codes with...

Performance of college athletes on the 10-item word list of SCAT5

ObjectivesThe Sport Concussion Assessment Tool-5 (SCAT5) was published in 2017; however, normative performance within the college athlete population on the optional 10-item word list has not been described. This study...

Nutrition as Medicine to Improve Outcomes in Adolescents Sustaining a Sports-related Concussion

Recognition and diagnosis of sports-related concussion (SRC) among adolescents has significantly increased. In, fact, among high school adolescents, SRC incidence has more than doubled from 2007 to 2014, with recent estimates at approximately 2 per 100 athletes. SRC-related research has also increased; recognition of symptoms that may prolong recovery have been examined, potential biomarkers have been scrutinized, return-to-learn and return-to-play protocols have been developed and honed. However, to date, clinicians and researchers have struggled to find effective interventions to mitigate the significant symptoms after SRC and shorten recovery times. Despite the understood role of the brain as the primary regulator of metabolism, and the well-established metabolic impairments evoked after a concussion, nutrition is often ignored as a core complement to the recovery and rehabilitation process. In this article, we will identify deficiencies and/or inadequacies in nutrients post-concussion and provide support for potential exacerbation of injury and delayed recovery due to inadequate intake of nutrients prior to sustaining an SRC. Additionally, we will discuss the effect of derangement of the metabolic cascade post-concussion, and identify key nutrients, that if supplemented immediately post-injury, could increase neuroprotection, and improve recovery outcomes. Animal and cell culture studies have provided substantial evidence for not only the interrelationship of nutrient adequacy and the adaptation in the metabolic cascade post-concussion on neuroprotection, but also key nutrients that if supplemented immediately post-injury could enhance standard of care with minimal risk.

Serum Tau Fragments Predict Return to Play in Concussed Professional Ice Hockey Players.

The diagnosis of sports-related concussion is mainly based on subjective clinical symptoms and neuropsychological tests. Therefore, reliable brain injury biomarkers to assess when it is safe to return to play are highly desirable. The overall objective of this study was to evaluate the utility of two newly described tau fragments for diagnosis and prognosis of sports-related concussions. This multi-center prospective cohort study involved all 12 teams of the top professional ice hockey league in Sweden. A total of 288 players consented to participate in the study. Thirty-five players sustained concussions, of whom 28 underwent repeated blood samplings at 1, 12, 36, and 144 h after the trauma, or when the player returned to play (7 to >90 days). There was no significant increase in the levels of Tau-A in post-concussion samples compared with preseason values. However, serum levels of Tau-C were significantly higher in post-concussion samples compared with preseason. Further, levels of Tau-A correlated with the duration of post-concussive symptoms. Tau-A in serum, which is newly discovered biomarker, could be used to predict when it is safe to return to play after a sports-related concussion.

An effective tool in establishing the diagnosis of sport-related concussion

An effective tool in establishing the diagnosis of sport-related concussion