Short-term changes in the physiology of the primary motor cortex following head impact exposure during a Canadian football game.

OBJECTIVE: This study investigated the association between head impact exposure (HIE) during varsity Canadian football games and short-term changes in cortical excitability of the primary motor cortex (M1) using transcranial magnetic stimulation (TMS). METHODS: Twenty-nine university-level male athletes wore instrumented mouth guards during a football game to measure HIE. TMS measurements were conducted 24 hours before and 1-2 hours after the game. Twenty control football athletes were submitted to a noncontact training session and underwent identical TMS assessments. Between-group changes in short-interval intracortical inhibition (SICI) ratios over time were conducted using two-way ANOVAs. The relationship between HIE (i.e., number, magnitude, and cumulative forces of impacts) and SICI (secondary outcome) was also investigated using Pearson correlations. RESULTS: Relative to controls, the group of athletes who had played a full-contact football game exhibited a significant intracortical disinhibition (p = 0.028) on the SICI 3-msec protocol (i.e., short interstimulus interval of 3 msec) within hours following the game. Moreover, exposure to ≥ 40g hits positively correlated with SICI disinhibition (p < 0.05). CONCLUSIONS: Athletes exposed to subconcussive hits associated with Canadian football exhibit abnormal M1 corticomotor inhibition function, particularly when the recorded impact magnitude was ≥ 40g. Given the deleterious effects of decreased inhibition on motor control and balance, systematically tracking head impact forces at each game and practice with contacts could prove useful for injury prevention in contact sports.

The Use of Electroencephalography as an Informative Tool in Assisting Early Clinical Management after Sport-Related Concussion: a Systematic Review.

Sport-related concussion (SRC) is managed primarily through serial clinical evaluations throughout recovery. However, studies suggest that clinical measures may not be suitable to detect subtle alterations in functioning and are limited by numerous internal and external factors. Electroencephalography (EEG) has been used for over eight decades to discern altered function following illnesses and injuries, including traumatic brain injury. This study evaluated the associations between EEG measures and clinical presentation within three-months following SRC. A systematic review of the literature was performed in Medline, Embase, PsycINFO, CINAHL and Web of Science databases following Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines, yielding a total of 13 peer-reviewed articles. Most studies showed low to moderate bias and moderate to high quality. The majority of the existing literature on the impact of concussion within the first 3 months post-injury suggests that individuals with concussion show altered brain function, with EEG abnormalities outlasting clinical dysfunction. Of all EEG biomarkers evaluated, P300 shows the most promise and should be explored further. Despite the relatively high quality of included articles, significant limitations are still present within this body of literature, including potential conflicts of interest and proprietary algorithms, making it difficult to draw strong and meaningful conclusions on the use of EEG in the early stages of SRC. Therefore, further exploration of the relationship between EEG measures and acute clinical presentation is warranted to determine if EEG provides additional benefits over current clinical assessments and is a feasible tool in clinical settings.

Test-retest reliability of the neurotracker compared to the impact test for the management of mild traumatic brain injuries during two consecutive university sport seasons.

INTRODUCTION: Neurocognitive assessment tools such as the Neurotracker and ImPACT have been proposed to optimize sports-related mild traumatic brain injury (mTBI) management. Baseline testing is recommended with such assessments to individualize monitoring of athletes' remission. While the ideal timeframe between baseline updates has been studied for the ImPACT, these data are missing for the Neurotracker. OBJECTIVE: The current study aimed to compare the test-retest reliability of the ImPACT and Neurotracker for two consecutive seasons in university athletes participating in sports at risk for mTBI. METHODS: At the start of two consecutive seasons, 30 athletes with no recent history of mTBI completed a baseline assessment including the Neurotracker and the ImPACT. The test-retest reliability of the results was analyzed by considering intra-class correlation (ICC), Becker's standardized mean difference (dB) and Bland-Altman' plot of each outcome. RESULTS: The Neurotracker and the Visual Motor Speed composite score of the ImPAC were the only outcomes with significative ICCs and acceptable dB between the two seasons. Neurotracker was the only outcome with a significative bias (+0.179). CONCLUSION: Our research suggests that the Neurotracker has an acceptable level of test-retest reliability after one year in comparison to the ImPACT.

Anthropometrics, Athletic Abilities and Perceptual-Cognitive Skills Associated With Baseball Pitching Velocity in Young Athletes Aged Between 10 and 22 Years Old.

Objective assessments of players performance and individual characteristics are increasingly used in baseball. However, evidence linking individual characteristics to players' performance are scarce. The purpose of the study was to identify across ages, in younger males and females, and to compare, in younger males, the anthropometrics, athletic abilities and perceptual-cognitive skills associated with baseball pitcher's ball velocity. A cross-sectional design was used to conduct this study. Male and female athletes completed a sociodemographic questionnaire followed by anthropometric, athletic ability, perceptual-cognitive skill and pitching velocity assessments. Athletes were categorized by their age categories (11U, 13U, 15U, 18U, 21U). To evaluate the athletes' anthropometrics, height and weight, BMI, waist circumference, arms segmental length and girth were measured. Athletic abilities were assessed using athletes' grip strength, upper body power, vertical jump height, sprint, change of direction, and dynamic balance. Perceptual-cognitive skills performance was assessed with the Neurotracker platform. Pitching performance assessment was completed using the athletes' average fastball velocity. Kendall Tau's correlation coefficient was used to assess relationships between variables and pitching velocity in male athletes (p < 0.05). A 1-way ANOVA was performed to identify differences between age categories for all variables in male athletes (p < 0.05). In male athletes, without age categories discrimination, all anthropometric, athletic ability and perceptual-cognitive skill factors were associated with pitching velocity with associations ranging from τ = 0.185 for perceptual-cognitive skills to τ = 0.653 for left arm grip strength. The results showed that significant differences exist between age categories for anthropometric, athletic ability and perceptual-cognitive skill assessments. The study showed that associations between anthropometrics and pitching velocity, and athletic abilities and pitching velocity vary across age categories. Descriptive data of female athletes results regarding anthropometrics, athletic abilities, perceptual-cognitive skills and pitching velocity are also presented. Gender differences should be investigated in future studies exploring baseball pitching performance.

The use of manual lymphatic drainage on clinical presentation of musculoskeletal injuries: A systematic review.

The aim of this study was to provide a systematic review on the applicability of manual lymphatic drainage (MLD) in improving edema and clinical presentation postmusculoskeletal injuries. A review of the literature was performed in CINAHL, MANTIS, Medline, SPORTDiscus and Google Scholar, yielding a total of 8 articles. Half of the studies showed a strong quality assessment. Results from our work support the use of MLD for reducing edema reduction and pain as well as enhancing range of motion and patients' quality of life and satisfaction. Further research is needed to apply these findings to a broader range of musculoskeletal injuries and conditions.

Perceptual Cognitive Training Does Not Improve Clinical Outcomes at 4 and 12 Weeks Following Concussion in Children and Adolescents: A Randomized Controlled Trial.

OBJECTIVE: To determine whether a perceptual-cognitive training program using 3D-multiple object tracking (3D-MOT) can improve symptoms following acute pediatric concussion. SETTING: Research laboratory within a pediatric trauma center. PARTICIPANTS: Children and adolescents (n = 62, age= 13.27 ± 2.50) with diagnosed concussion. DESIGN: Randomized controlled trial. Children were randomized into either 3D-MOT, 2048 game, or standard care-only groups. Participants and parents completed the Post-Concussion Symptom Inventory (PCSI) at baseline, 4, 8, and 12 weeks postinjury. Intervention participants completed either the 3D-MOT protocol or the 2048 game at 6 sessions between the baseline and 4-week assessment. MAIN MEASURES: A 3 (group) × 10 (time) mixed-model analysis of variance evaluated PCSI total scores. The rate of persistent postconcussive symptom (PPCS) was evaluated at 4 weeks using χ2 analysis. RESULTS: Symptoms decreased throughout the study using both child-reported (F(9,374) = 22.03, P < .001) and parent-reported scores (F(9,370) = 28.06, P < .001). Twenty-four (44.4%) children met the study definition for PPCS using the child-reported PCSI, while 20 (37.7%) children had PPCS using parent reports. The intervention did not significantly affect symptom resolution or PPCS rates. CONCLUSION: There is no benefit to prescribing 3D-MOT training for acute rehabilitation in pediatric patients with concussion and clinicians should instead focus on more effective programs.

Could Neurotracker be used as a clinical marker of recovery following pediatric mild traumatic brain injury? An exploratory study.

PRIMARY OBJECTIVE: This study aimed to explore the potential for the Neurotracker, a perceptual-cognitive, multiple-object tracking test, and train paradigm, as a marker of functional recovery after mild traumatic brain injury (mTBI). It is hypothesized that Neurotracker could serve as a proxy for assessing cerebral functioning. RESEARCH DESIGN: A comparative, 6 time points, longitudinal study design was used to compare Neurotracker performance between children and adolescents who were clinically recovered from mTBI and healthy controls. METHODS AND PROCEDURES: Clinical measures were collected at the initial and final visits. Neurotracker trainings were performed at each of the 6 visits. Speed thresholds (Neurotracker performance) were recorded at each visit. MAIN OUTCOMES AND RESULTS: A two-way repeated measures ANOVA suggested no differences between the groups but a significant time effect was apparent. CONCLUSIONS: Clinically recovered children and adolescents exhibit similar training abilities to control subjects on this task. These results support further investigations using Neurotracker as a marker of recovery following mTBI.

Three-dimensional multiple object tracking in the pediatric population: the NeuroTracker and its promising role in the management of mild traumatic brain injury.

As mild traumatic brain injury (mTBI) affects hundreds of thousands of children and their families each year, investigation of potential mTBI assessments and treatments is an important research target. Three-dimensional multiple object tracking (3D-MOT), where an individual must allocate attention to moving objects within 3D space, is one potentially promising assessment and treatment tool. To date, no research has looked at 3D-MOT in a pediatric mTBI population. Thus, the aim of this study was to examine 3D-MOT learning in children and youth with and without mTBI. Thirty-four participants (mean age=14.69±2.46 years), with and without mTBI, underwent six visits of 3D-MOT. A two-way repeated-measures analysis of variance (ANOVA) showed a significant time effect, a nonsignificant group effect, and a nonsignificant group-by-time interaction on absolute speed thresholds. In contrast, significant group and time effects and a significant group-by-time interaction on normalized speed thresholds were found. Individuals with mTBI showed smaller training gains at visit 2 than healthy controls, but the groups did not differ on the remaining visits. Although youth can significantly improve their 3D-MOT performance following mTBI, similar to noninjured individuals, they show slower speed of processing in the first few training sessions. This preliminary work suggests that using a 3D-MOT paradigm to train visual perception after mTBI may be beneficial for both stimulating recovery and informing return to activity decisions.

Postconcussion Symptoms as a Marker of Delayed Recovery in Children and Youth Who Recently Sustained a Concussion: A Brief Report.

OBJECTIVE: To identify predictors of delayed recovery in children who sustained a concussion and sought care in a pediatric hospital. DESIGN: Retrospective cohort study design. SETTING: Montreal Children's Hospital Concussion Clinic database. PATIENTS: Children who sustained a concussion and sought care within 10 days of the injury, with complete medical history and Postconcussion Symptom Scale (PCSS) score available. INDEPENDENT VARIABLES: Total symptom score on the PCSS, sex, age, history of concussion, sleep disturbances, anxiety, learning disabilities, attention problems, and depression. MAIN OUTCOME MEASURE: Delayed recovery (28 days or more). RESULTS: A total of 213 children (F = 76, M = 138) with a mean age of 13.89 ± 2.55 years were included. Only total PCSS score at 10 days postinjury was identified as a significant predictor of delayed recovery (odds ratio: 1.019, P = 0.01). CONCLUSIONS: This study demonstrates the potential for clinicians to identify, with the sole use of the PCSS, children at risk of experiencing symptoms for longer periods of time.

Developmental trajectories of infants and toddlers with good initial presentation following moderate or severe traumatic brain injury: a pilot clinical assessment project.

OBJECTIVE: The purpose of this study was to review the feasibility and usefulness of instituting a clinical protocol of scheduled assessments for children after a moderate or severe traumatic brain injury (TBI) sustained before the age of 2 years and showing no immediate deficits at hospital discharge, as well as to explore the early developmental trajectories of these children. DESIGN: Exploratory analytical cohort study. SETTING: Pediatric Trauma Center Out-patient services. PARTICIPANTS: 31 children were followed within the clinical protocol of scheduled assessments. OUTCOME MEASURES: The protocol included an immediate post-injury clinical assessment of infants who sustained a TBI and follow-up assessments at the ages of 9 months, 18 months (if injured prior to that age), 30 months, and 42 months. Domains assessed at each scheduled visit included hearing, speech and language, motor performance, personal social abilities, and adaptive behaviors. RESULTS: Clinicians reported few difficulties with scheduling or administering the assessments, maintaining a 67% participation rate at the end of the follow-up period, thus demonstrating the feasibility of the protocol in this population. Scores on the majority of formal tests showed high variability and 15-20% of children presented with clinically significant motor and/or language delays. By 42 months of age, difficulties with adaptive behavior and personal social abilities were identified in our sample of children when compared to published norms. Qualitative clinical findings from professionals identified between 25-50% of children with potential attentional difficulties throughout the follow-up period. CONCLUSION: Findings from this study demonstrate the feasibility of implementing a clinical protocol of assessment for infants and toddlers who sustain a TBI before the age of 2 years and present with no impairments at the time of discharge from hospital. Developmental problems in this population appear to be easier to identify later in the toddler years as opposed to immediately following the TBI, emphasizing the importance of providing screening for developmental issues in this population prior to school entry.