Influence of sleep symptoms on recovery from concussion in collegiate athletes: a LIMBIC MATARS consortium investigation.

OBJECTIVE: Changes in sleep quality and quantity are commonly endorsed by individuals following a concussion. Limited data exists examining the role of sleep disturbances within 72 hours, and throughout recovery, from concussion. The objective of this study was to determine if the number of days to symptom resolution varied between collegiate athletes with or without sleep-related symptoms following a concussion. DESIGN: Retrospective chart review. METHODS: Collegiate athletes (n = 539) who were diagnosed with a concussion between the 2015-2020 sport seasons participated in this retrospective chart review. Participants were divided into groups based on the presence or absence of sleep symptoms within 72 hours of a diagnosed concussion. A Mann-Whitney U test was used to compare days to symptom resolution between groups with α = 0.05. RESULTS: Of the 539 participants, 250 (46.3%) reported sleep-related symptoms. Participants with sleep-related symptoms took significantly longer (U = 30656, p = 0.002) to report symptom resolution at rest (median [full range] = 8.00[0-423]) as compared to participants who did not report sleep-related symptoms (6.00[0-243] days). CONCLUSION: Collegiate athletes that report sleep-related symptoms immediately following concussion (<72 hours) were observed to take, on median, two days longer to achieve symptom resolution at rest when compared to athletes who did not endorse the same symptoms.

Sport Type and Risk of Subsequent Injury in Collegiate Athletes Following Concussion: a LIMBIC MATARS Consortium Investigation.

OBJECTIVE: To investigate the association between sport type (collision, contact, non-contact) and subsequent injury risk following concussion in collegiate athletes. MATERIALS AND METHODS: This retrospective chart review of 248 collegiate athletes with diagnosed concussions (age: 20.0 ± 1.4 years; height: 179.6 ± 10.9 cm; mass: 79.0 ± 13.6 kg, 63% male) from NCAA athletic programs (n = 11) occurred between the 2015-2020 athletic seasons. Acute injuries that occurred within six months following concussion were evaluated. Subsequent injuries were grouped by lower extremity, upper extremity, trunk, or concussion. The independent variable was sport type: collision, contact, non-contact. A Cox proportional hazard model was used to assess the risk of subsequent injury between sport types. RESULTS: Approximately 28% (70/248) of athletes sustained a subsequent acute injury within six months post-concussion. Collision sport athletes had a significantly higher risk of sustaining any injury (HR: 0.41, p < 0.001, 95% CI: 0.28, 0.62), lower extremity (HR: 0.55, p = 0.04, 95% CI: 0.32, 0.97), and upper extremity (HR: 0.41, p = 0.01, 95% CI: 0.20, 0.81) injuries following concussion. No differences between sport types were observed for other injuries. CONCLUSION: Collision sport athletes had a higher rate of any subsequent injury, lower, and upper extremity injuries following concussion. Future research should focus on sport-specific secondary injury prevention efforts.

Access to athletic trainers and sex as modifiers of time to reach clinical milestones after sport-related concussion in collegiate athletes.

OBJECTIVE: Investigate whether an athlete's biological sex and exposure to a dedicated athletic trainer (AT) were related to clinical milestones after a sports-related concussion (SRC). DESIGN: Retrospective chart review. METHODS: Medical charts of collegiate athletes (n = 196 [70.9% female]) diagnosed with SRC were reviewed to extract: biological sex, dedicated AT exposure for their sport (yes/no), and time (days) to reaching clinical milestones (diagnosis, symptom resolution, unrestricted return to sport [RTS]). Mann-Whitney U tests were used to determine whether time to clinical milestones differed by sex, AT exposure, or their interaction. Proportions of same-day diagnoses and times to diagnosis, symptom resolution, and unrestricted RTS were evaluated with chi-squared and spearman's rank correlations, respectively. RESULTS: There were no significant differences in times to reaching any clinical milestone by sex, AT exposure, or their interaction (ps > 0.05). Forty-three percent of participants were diagnosed on the day of their SRC. This did not differ by sex or AT exposure (ps > 0.29). Longer times to SRC diagnosis were associated with more days to symptom resolution (ρ = 0.236, p = 0.001) and unrestricted RTS (ρ = 0.223, p < 0.001). CONCLUSIONS: Athlete sex and AT exposure were not associated with times to reach any clinical milestone; however, delayed diagnosis was associated with longer times to reach clinical recovery.

Physical activity and recovery following concussion in collegiate athletes: a LIMBIC MATARS Consortium Investigation.

OBJECTIVE: To investigate whether routine daily activities (RDA), non-prescribed exercise (Non-ERx), or prescribed exercise (ERx) were associated with recovery from sport-related concussion (SRC) in collegiate athletes. MATERIALS AND METHODS: Data for this cross-sectional, retrospective chart review of collegiate athletes diagnosed with SRC (n = 285[39.6% female], age = 19.5 ± 1.4 years) were collected during the 2015-16 to 2019-20 athletic seasons. The independent variable was group (RDA, Non-ERx, ERx). Dependent variables included days from date of diagnosis to symptom resolution (Dx-SR) and SR to return to sport (SR-RTS). RESULTS: Those in the Non-ERx group took nearly 1.3 times longer to achieve SR (IRR = 1.28, 95% CI: 1.11, 1.46) and, 1.8 times longer for RTS (IRR = 1.82, 95% CI: 1.11, 2.71) when compared to those in the RDA group. No other comparisons were significant. CONCLUSION: Collegiate athletes in the Non-ERx group took approximately 1 week longer to achieve SR as compared to the RDA and ERx groups. Our findings suggest that if exercise is recommended following SRC, it must be clearly and specifically prescribed. If exercise parameters cannot be prescribed, or monitored, RDA appear to be similarly beneficial during recovery for collegiate athletes with concussion.

The influence of ADHD on recovery from sport concussion among collegiate athletes in the United States: LIMBIC MATARS consortium investigation.

OBJECTIVE: The present study aimed to assess the potential influence of a diagnosis of ADHD on concussion recovery among collegiate athletes. DESIGN: Retrospective and cross-sectional. METHODS: Data were extracted retrospectively from medical records across LIMBIC MATARS member institutions (n = 11), representing 1,044 concussion cases among collegiate athletes. After exclusions, 406 concussions were included in our analysis (ADHD: n = 38, age = 20.2 ± 1.67 years, 18.4% female; No ADHD: n = 368, age = 19.8 ± 1.39 years, 40.1% female). Mann-Whitney U tests were used to compare days from injury to diagnosis, symptom resolution, and return to sport among athletes with and without ADHD. RESULTS: No differences were observed for days from concussion until diagnosis (z = -0.33, p = 0.74), until days to symptom resolution (z = -1.30, p = 0.19), or days until return to sport (z = -0.68, p = 0.49); among concussion cases with or without a previously reported diagnosis of ADHD. CONCLUSION: Our findings further expand the literature that suggests ADHD is not strongly associated with recovery trajectory following sport concussion in collegiate athletes. Future research should extend these findings to be inclusive of additional preexisting health conditions and moderating effects related to medication usage among diverse athlete levels.

Concussion Symptoms and Neurocognitive Performance of Children and Adolescents on Antidepressants.

INTRODUCTION/PURPOSE: There is a well-established association between preexisting depression/anxiety and greater postconcussion symptom burden, but the potential impact of antidepressant medications has not been fully explored. The primary objective of this study was to compare preinjury/baseline and postinjury concussion symptom scores and neurocognitive performance of athletes on antidepressant medications, both with healthy controls and with those with depression/anxiety not on antidepressants. METHODS: This is a cross-sectional study using data collected from 49,270 junior and high school athletes from computerized neurocognitive assessments (Immediate Post-Concussion Assessment and Cognitive Test [ImPACT]) administered between 2009 and 2018 held by the Massachusetts Concussion Management Coalition. The main outcome measures were symptom scores and neurocognitive performance measures, all of which were assessed both at baseline and postinjury. Statistical analysis included analysis of variance and Tukey pairwise comparisons for continuous variables and Fisher's exact test for categorical variables. Multivariate regression models were used to adjust for potential confounding variables. RESULTS: Both at baseline and postinjury, athletes with depression/anxiety had mean total symptom scores that were more than double that of healthy controls regardless of antidepressant use. Although there were no significant differences in neurocognitive performance at baseline, depression/anxiety was associated with small but significant decreases in postinjury visual memory and visual motor scores. CONCLUSIONS: Both at baseline and after sustaining a concussion, young athletes with depression/anxiety experience significantly greater symptom burden compared with healthy controls regardless of antidepressant use.

Predictors of Speech Language Pathology Referral After Pediatric Concussion Using a Speech Language Checklist.

ABSTRACT: Speech language pathologists have the training to treat pediatric concussion issues in communication; however, they have traditionally not been included in initial concussion treatment. Despite physician understanding of speech language pathologist engagement in traumatic brain injury, speech language pathologist referrals happen only after significant issues in returning to school occurred. Therefore, the purpose of this study was to investigate predictors of physician referral to speech language pathologist using a speech language pathologist screening checklist. This was a retrospective, cross-sectional study from an academic outpatient clinic. Our study included 60 concussion patients (57% female, 67% White, age: 18.3 ± 4.0 years) who were evaluated by specialist physicians. The independent variables include age, sex, and the speech screening checklist domains (attention, memory/organization, social interactions, word finding, executive function) and their associated subcategories. The primary study outcome was referral to speech language pathologists after concussion. Twenty-six patients (43%) were referred to speech language pathologist. The speech checklist domains significantly associated with a referral to speech language pathologist were attention and memory/organization. Individuals who reported trouble with attention or memory/organization on the speech language checklist were most likely to be referred in a concussion treatment plan. The use of a speech language pathologist checklist during patient visits may expedite referrals to SLP, achieve earlier therapeutic intervention, and facilitate recovery.

Influential Factors and Preliminary Reference Data for a Clinically Feasible, Functional Reaction Time Assessment: The Standardized Assessment of Reaction Time.

CONTEXT: Clinical reaction-time (RT) measures are frequently used when examining patients with concussion but do not correlate with functional movement RT. We developed the Standardized Assessment of RT (StART) to emulate the rapid cognitive demands and whole-body movement needed in sport. OBJECTIVE: To assess StART differences across 6 cognitive-motor combinations, examine potential demographic and health history confounders, and provide preliminary reference data for healthy collegiate student-athletes. DESIGN: Prospective, cross-sectional study. SETTING: Clinical medicine facilities. PATIENTS OR OTHER PARTICIPANTS: A total of 89 student-athletes (56 [62.9%] men, 33 [37.1%] women; age = 19.5 ± 0.9 years, height = 178.2 ± 21.7 cm, mass = 80.4 ± 24 kg; no concussion history = 64 [71.9%]). MAIN OUTCOME MEASURE(S): Student-athletes completed health history questionnaires and StART during preseason testing. The StART consisted of 3 movements (standing, single-legged balance, and cutting) under 2 cognitive states (single task and dual task [subtracting by 6's or 7's]) for 3 trials under each condition. The StART trials were calculated as milliseconds between penlight illumination and initial movement. We used a 3 × 2 repeated-measures analysis of variance with post hoc t tests and 95% CIs to assess StART cognitive and movement differences, conducted univariable linear regressions to examine StART performance associations, and reported StART performance as percentiles. RESULTS: All StART conditions differed (P ≤ .03), except single-task standing versus single-task single-legged balance (P = .36). Every 1-year age increase was associated with an 18-millisecond (95% CI = 8, 27 milliseconds) slower single-task cutting RT (P < .001). Female athletes had slower single-task (15 milliseconds; 95% CI = 2, 28 milliseconds; P = .02) and dual-task (28 milliseconds; 95% CI = 2, 55 milliseconds; P = .03) standing RT than male athletes. No other demographic or health history factors were associated with any StART condition (P ≥ .056). CONCLUSIONS: The StART outcomes were unique across each cognitive-motor combination, suggesting minimal subtest redundancy. Only age and sex were associated with select outcomes. The StART composite scores may minimize confounding factors, but future researchers should consider age and sex when providing normative data.

Clinical Mental Health Measures and Prediction of Postconcussion Musculoskeletal Injury.

CONTEXT: The rate of lower extremity musculoskeletal injury (LE MSK) is elevated after concussion; however, the underlying mechanism has not been elucidated. Physical characteristics have been investigated despite poorer mental health being a common postconcussion complaint and linked to MSKs. OBJECTIVE: To evaluate the role of mental health as a predictor of postconcussion LE MSK. DESIGN: Case-control study. SETTING: Intercollegiate athletic training facility. PATIENTS OR OTHER PARTICIPANTS: A total of 67 National Collegiate Athletic Association Division I student-athletes (n = 39 females) who had been diagnosed with a sport-related concussion. MAIN OUTCOME MEASURE(S): The Brief Symptom Inventory-18, Hospital Anxiety and Depression Scale, and Satisfaction With Life Scale (SWLS) measures were completed at baseline (preseason) and on the day participants were cleared for unrestricted return to play (RTP) after a concussion. Two binary logistic regressions were used to predict postconcussion LE MSK within a year, one for the baseline time point and the second for the RTP time point. A 2 (group: LE MSK, no LE MSK)-by-2 (time: baseline, RTP) repeated-measures analysis of variance compared performance between baseline and RTP. RESULTS: Subsequent LE MSKs were sustained by 44 participants (65.7%). The only significant predictor of postconcussion LE MSK was the SWLS score at RTP, with Exp(B) = 0.64, indicating that an increased (improved) SWLS score was associated with a lower LE MSK rate. No significant interactions were present between mental health measures and subsequent MSK (P values = .105-.885). CONCLUSIONS: Limited associations were evident between postconcussion LE MSK and scores on commonly used measures of anxiety, depression, and satisfaction with life. Reported increased satisfaction with life was associated with a decreased injury risk, which warrants further attention. Our results suggest that these measures of anxiety, depression, and satisfaction with life have limited value in assisting sports medicine clinicians with determining which student-athletes are at elevated risk of postconcussion LE MSK.

No Association Between Processing Speed and Risk of Sport-Related Concussion in Youth Soccer.

OBJECTIVE: To determine whether slow processing speed is associated with risk of sport-related concussion. DESIGN: We conducted a retrospective cohort study using computerized neurocognitive assessments (Immediate Post-concussion Assessment and Cognitive Testing [ImPACT]) from the Massachusetts Concussion Management Coalition. Slow processing speed was defined as 2 SD below the sample mean (n = 131) and fast processing speed as 2 SD above the sample mean (n = 259). We used a binary logistic regression model to determine the odds of sustaining a concussion with our main predictor being processing speed (high or low) adjusted for the effects of age, sex, and prior number of concussions. SETTING: Massachusetts Concussion Management Coalition, Institutional care. PARTICIPANTS: Three hundred ninety junior high soccer players ages 10 to 15 with a baseline score for ImPACT. INDEPENDENT VARIABLES: Processing Speed. MAIN OUTCOME MEASURES: Risk of sustaining a concussion. RESULTS: Those with slow processing speed had a visual motor composite score of ≤19.92, those with fast-processing speed had a score of ≥46.20. Athletes with slow processing speed were younger (13 vs 14 years; P < 0.001) and more likely to be male (57% vs 49%; P = 0.014). After adjusting for the effects of age, sex, and prior concussions, there was no significant difference in the odds of sustaining a concussion between groups (aOR 1.01; 95% CI, 0.99-1.04). CONCLUSIONS: Despite previous research showing that slow processing speed is a risk factor for musculoskeletal injuries during sports, our study suggests that processing speed is not associated with the risk of sustaining a concussion among junior high school soccer players.

Association Between Collision Sport Career Duration and Gait Performance in Male Collegiate Student-Athletes.

BACKGROUND: Investigations of estimated age of first exposure to repetitive head impacts from collision and contact sports have shown no associations with neurocognitive or neurobehavioral function at the collegiate level, but the effect of career duration may be a more comprehensive factor. Understanding whether longer career duration influences gait performance would provide insights into potential neurological impairment. PURPOSE: To examine the relationship between career duration of collision sports and single/dual-task gait performance in collegiate student-athletes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: We recruited 168 male student-athletes from collision sports: football, lacrosse, ice hockey, and wrestling (mean ± SD age, 19.2 ± 1.3 years; height, 184.5 ± 7.2 cm; mass, 94.3 ± 15.9 kg; estimated age of first exposure, 8.6 ± 3.1 years; career duration, 10.6 ± 3.0 years). All participants completed a baseline single- and dual-task gait assessment before the start of their athletic season. Inertial measurement units were used to measure gait speed and stride length. During the dual task, participants were asked to perform working memory cognitive tasks while walking. The dependent variables were single/dual-task gait speed and stride length, cognitive accuracy, and dual-task cost. The relationship between career duration, analyzed as a continuous variable, and the dependent variables was analyzed using a linear regression. RESULTS: There were no significant associations between career duration and single-task gait speed (1.16 ± 0.16 m/s; ß = -0.004; P = .35; 95% CI = -0.012 to 0.004; η2 = 0.005) or dual-task gait speed (1.02 ± 0.17 m/s; ß = -0.003; P = .57; 95% CI = -0.011 to 0.006; η2 = 0.002). There were also no significant associations between career duration and single/dual-task stride length, cognitive accuracy, or dual-task cost. CONCLUSION: Career duration among collegiate collision sport athletes was not associated with single- or dual-task gait performance, suggesting that a greater exposure to repetitive head impacts is not detrimental to dynamic postural control at the college level. However, the effects of diminished gait performance over the lifetime remain to be elucidated.

Neurocognitive functioning and symptoms across levels of collision and contact in male high school athletes.

OBJECTIVE: We sought to determine whether male collision sport athletes perform worse on computerised neurocognitive assessments and report higher symptom burdens than athletes in contact (but not collision) sports and athletes in non-contact sports. METHODS: This cross-sectional study used data collected by the Massachusetts Concussion Management Coalition on high school boys who underwent computerised neurocognitive testing between 2009 and 2018. We divided sports participation in three different sport types: (1) collision, (2) contact, non-collision and (3) non-contact. Our outcomes included the four computerised neurocognitive composite scores (verbal memory, visual memory, visual motor speed and reaction time) and the total symptom score. The independent variable was sport type (collision, contact, non-contact), adjusted for age, concussion history and comorbidities. RESULTS: Of the 92 979 athletes (age: 15.59±2.08 years) included in our study, collision sport athletes performed minimally but significantly worse than other athletes on neurocognitive composite scores (verbal memory: ß=-1.64, 95% CI -1.85 to -1.44; visual memory: ß=-1.87, 95% CI -2.14 to -1.60; visual motor speed: ß=-2.12, 95% CI -2.26 to -1.97; reaction time: ß=0.02, 95% CI 0.02 to 0.02). Collision and contact sport athletes also had slightly but significantly lower total symptom scores (collision: 3.99±7.17; contact: 3.78±6.81; non-contact: 4.32±7.51, p<0.001, η2=0.001) than non-contact sport athletes. CONCLUSION: There are minimal observed differences in performance on neurocognitive assessments between collision sport, contact sport and non-contact sport athletes. The repetitive subconcussive head impacts associated with collision sport participation do not appear to negatively affect self-reported symptoms or neurocognitive functioning in current youth athletes.

Association of Social Media Use on Sleep Quality and Performance Among Collegiate Athletes.

OBJECTIVE: (1) To examine the effect of social media (SM) use on sleep quality and (2) to determine the effect of SM on competition performance among college athletes. DESIGN: Cross-sectional study. SETTING: Two local Division III colleges, MA, USA. PARTICIPANTS: National Collegiate Athletic Association Division III swim and track and field athletes. INTERVENTION: Data were collected onsite through an SM use form, the lifestyle survey, and the Patient-Reported Outcomes Measurement Information System Sleep Disturbance Questionnaire. Participants were divided into 3 groups based on their SM volume: (1) less active SM users (≤2 h/d), (2) moderately active SM users (>2-≤5 h/d), and (3) active SM users (>5 h/d) for analysis. MAIN OUTCOME MEASURES: Sleep quality and sport performance data collected through publicly available competition results. The independent variable, SM volume (hours of SM use per day over 7 days), was collected using the iPhone screen time function. RESULTS: The cohort consisted of 40 male track and field athletes and 47 female track and field (37, 79%) and swimming (10, 21%) athletes. Mean SM use was 4.6 ± 3.4 h/d. The sleep quality of active SM users was worse than less active SM users ( P = 0.033). There was an independent association between increased Facebook time and poor performance after adjusting confounders (adjusted odds ratio: 0.990, 95% confidence interval: 0.981-0.999, P = 0.049). CONCLUSIONS: High SM use has a negative impact on sleep quality and may hinder competition performance among college athletes. These findings may have implications for developing SM use guidelines for college athletes to improve their sleep quality and performance.

Dizziness, Psychosocial Function, and Postural Stability Following Sport-Related Concussion.

OBJECTIVE: To examine if self-reported dizziness is associated with concussion symptoms, depression and/or anxiety symptoms, or gait performance within 2 weeks of postconcussion. DESIGN: Cross-sectional study. SETTING: Research laboratory. PARTICIPANTS: Participants were diagnosed with a concussion within 14 days of initial testing (N = 40). Participants were divided into 2 groups based on their Dizziness Handicap Inventory (DHI) score: 36 to 100 = moderate/severe dizziness and 0 to 35 = mild/no dizziness. INTERVENTIONS: Participants were tested on a single occasion and completed the DHI, hospital anxiety and depression scale (HADS), Patient Health Questionnaire-9 (PHQ-9), and Post-Concussion Symptom Inventory (PCSI). Three different postural control tests were use: modified Balance Error Scoring System, single-/dual-task tandem gait, and a single-/dual-task instrumented steady-state gait analysis. MAIN OUTCOME MEASURES: Comparison of patient-reported outcomes and postural control outcomes between moderate/severe (DHI ≥ 36) and mild/no (DHI < 36) dizziness groups. RESULTS: Participants with moderate/severe dizziness (n = 19; age = 17.1 ± 2.4 years; 63% female) reported significantly higher symptom burden (PSCI: 43.0 ± 20.6 vs 22.8 ± 15.7; P = 0.001) and had higher median HADS anxiety (6 vs 2; P < 0.001) and depression (6 vs 1; P = 0.001) symptom severity than those with no/minimal dizziness (n = 21; age = 16.5 ± 1.9; 38% female). During steady-state gait, moderate/severe dizziness group walked with significantly slower single-task cadence (mean difference = 4.8 steps/minute; 95% confidence interval = 0.8, 8.8; P = 0.02) and dual-task cadence (mean difference = 7.4 steps/minute; 95% confidence interval = 0.7, 14.0; P = 0.04) than no/mild dizziness group. CONCLUSION: Participants who reported moderate/severe dizziness reported higher concussion symptom burden, higher anxiety scores, and higher depression scores than those with no/mild dizziness. Cadence during gait was also associated with the level of dizziness reported.

Postconcussion Exercise Volume Associations With Depression, Anxiety, and Dizziness Symptoms, and Postural Stability: Preliminary Findings.

OBJECTIVE: To examine the association between postconcussion exercise volume and changes in depression, anxiety, dizziness, and postural stability. DESIGN: Secondary analysis of a single-site prospective clinical trial. SETTING: Cerebrovascular research laboratory. PARTICIPANTS: Participants completed questionnaires and underwent tests of gait and balance within 2 weeks of a concussion (mean = 11 ± 3 days postconcussion) and approximately 1 month later (mean = 41 ± 7 days postconcussion). Exercise volume was tracked by weekly exercise logs. INTERVENTIONS: On the basis of a previous work classifying exercise volume following concussion, we grouped participants according to self-reported exercise volume between visits as high exercise volume (≥150 min/wk) or low exercise volume (<150 min/wk). MAIN OUTCOME MEASURES: Participants completed assessments evaluating anxiety and depression (Hospital Anxiety and Depression Scale), dizziness (Dizziness Handicap Inventory), and postural stability (tandem gait and modified Balance Error Scoring System). RESULTS: Thirty-eight participants completed the study, of which 22 were in the high exercise volume group (mean = 71 ± 40 min/wk; 16.8 ± 2.1 years; 59% female) and 16 were in the low exercise volume group (mean = 379 ± 187 min/wk; 17.5 ± 2.1 years; 31% female). Although depression symptoms were not significantly different initially (mean difference = 1.5; 95% CI, -0.68 to 3.68; P = .24), the high exercise volume group had significantly lower depression symptom scores at follow-up (mean difference = 3.0; 95% CI, 1.40 to 4.47; P < .001). Anxiety symptoms (mean difference = 2.8; 95% CI, 0.3 to 5.4; P = 0.03), dizziness symptoms (mean difference = 10.9; 95% CI, 0.2 to 21.5; P = .047), single-task tandem gait (mean difference = 3.1 seconds; 95% CI, 0.2 to 6.0; P = .04), and dual-task tandem gait (mean difference = 4.2 seconds; 95% CI, 0.2 to 8.2; P = .04) were significantly better among the high exercise volume group. CONCLUSION: Greater exercise volumes were associated with lower depression, anxiety, and dizziness symptoms, and faster tandem gait performance. These preliminary findings suggest a potentially beneficial role for exercise within several different domains commonly affected by concussion.

The Association between Baseline Eye Tracking Performance and Concussion Assessments in High School Football Players.

SIGNIFICANCE: Concussions are complex injuries that require a multifaceted testing battery. Vision impairments are common after concussion, but it is unknown exactly how eye tracking may be affected after injury and how it is associated with other clinical concussion assessments. PURPOSE: This study aimed to (1) examine the relationship between eye tracking performance (BOX score) and other common concussion evaluations, (2) identify if eye tracking adds novel information that augments baseline concussion evaluations, and (3) examine the effect of age, concussion history, and attention-deficit/hyperactivity disorder on eye tracking and other ophthalmological measures. METHODS: A total of 102 male high school football athletes (age, 16.0 years; 95% confidence interval, 15.8 to 16.2 years) completed a series of visual and neurocognitive tests during their pre-season baseline assessment. The main outcome measures were BOX score, near point of convergence (NPC) distance, binocular accommodative amplitude (BAA) distance, Standardized Assessment of Concussion score, and Immediate Post-Concussion Assessment and Cognitive Testing composite scores. RESULTS: BOX score was not significantly associated with symptoms, Standardized Assessment of Concussion score, NPC distance, BAA distance, or any Immediate Post-Concussion Assessment and Cognitive Testing composite scores. Age, concussion history, attention-deficit/hyperactivity disorder, and number of prior years playing football were not significantly associated with BOX score or NPC distance, but there was a significant association between concussion history and greater BAA distance (ß = 1.60; 95% confidence interval = 0.19 to 3.01; P < .03). The BOX score cutoff of 10 resulted in a 12% false-positive rate. CONCLUSIONS: Eye tracking was not significantly associated with the commonly used clinical concussion assessments. These results suggest that an objective eye tracking variable may be a valuable addition to the current concussion battery.

Impaired eye tracking is associated with symptom severity but not dynamic postural control in adolescents following concussion.

PURPOSE: The purpose of the study was to (1) examine the relationship between self-reported symptoms and concussion-related eye tracking impairments, and (2) compare gait performance between (a) adolescents with a concussion who have normal eye tracking, (b) adolescents with a concussion who have abnormal eye tracking, and (c) healthy controls. METHODS: A total of 30 concussed participants (age: 14.4 ± 2.2 years, mean ± SD, 50% female) and 30 controls (age: 14.2 ± 2.2 years, 47% female) completed eye tracking and gait assessments. The BOX score is a metric of pupillary disconjugacy, with scores <10 classified as normal and ≥10 abnormal. Symptoms were collected using the Post-Concussion Symptom Scale (PCSS), and gait speed was measured with triaxial inertial measurement units. We conducted a linear regression to examine the relationship between PCSS and BOX scores and a two-way mixed effects analysis of variance to examine the effect of group (abnormal BOX, normal BOX, and healthy control) on single- and dual-task gait speed. RESULTS: There was a significant association between total PCSS score and BOX score in the concussion group (ß = 0.16, p = 0.004, 95% confidence interval (95%CI): 0.06‒0.27), but not in the control group (ß = 0.21, p = 0.08, 95%CI: -0.03 to 0.45). There were no significant associations between PCSS symptom profiles and BOX scores in the concussion or control groups. There were also no significant differences in single-task (Abnormal: 1.00 ± 0.14 m/s; Normal: 1.11 ± 0.21 m/s; Healthy: 1.14 ± 0.18 m/s; p = 0.08) or dual-task (Abnormal: 0.77 ± 0.15 m/s; Normal: 0.84 ± 0.21 m/s; Healthy: 0.90 ± 0.18 m/s; p = 0.16) gait speed. CONCLUSION: The concussed group with impaired eye tracking reported higher total symptom severity, as well as worse symptom severity across the 5 PCSS symptom domain profiles. However, eye tracking deficits did not appear to be driven by any particular symptom domain. While not statistically significant, the slower gait speeds in those with abnormal BOX scores may still be clinically relevant since gait-related impairments may persist beyond clinical recovery.

Single-Task and Dual-Task Tandem Gait Performance Across Clinical Concussion Milestones in Collegiate Student-Athletes.

OBJECTIVE: To determine the length of time after concussion that impaired tandem gait performance is observed. DESIGN: Clinical measurement, prospective longitudinal. SETTING: NCAA collegiate athletic facility. PARTICIPANTS: Eighty-eight concussed NCAA Division I student-athletes and 30 healthy controls. INDEPENDENT VARIABLES: Group (concussion/control) and time (Baseline, Acute, Asymptomatic, and RTP). MAIN OUTCOME MEASURES: Participants completed 4 single-task and dual-task tandem gait trials. The concussion group completed tests at the following time points: preseason (Baseline), within 48 hours after concussion (Acute), on the day symptoms were no longer reported (Asymptomatic), and when cleared to return to sports (RTP). Controls completed the same protocol at similar intervals. The dual-task trials involved minimental style cognitive questions answered simultaneously during tandem gait. We analyzed the best time of the 4 trials, comparing groups with a linear mixed model. RESULTS: Acutely after concussion, the concussion group performed single-task tandem gait slower (worse) than controls (concussion: 11.36 ± 2.43 seconds, controls: 9.07 ± 1.78 seconds, P < 0.001). The concussion group remained significantly slower than controls (9.95 ± 2.21 vs 8.89 ± 1.65 seconds, P = 0.03) at Asymptomatic day but not RTP. There were significant group (P < 0.001) and time (P < 0.001) effects for dual-task tandem gait. The groups were not significantly different at baseline for single-task (P = 0.95) or dual-task (P = 0.22) tandem gait. CONCLUSIONS: Our results indicate that tandem gait performance is significantly impaired acutely after concussion, compared with both preseason measures and controls. Postural control impairments were not present when the student-athletes were cleared for RTP. This information can assist clinicians when assessing postural control and determining recovery after a concussive injury.

Impairments in Dynamic Postural Control across Concussion Clinical Milestones.

The aim of this study was to assess gait initiation (GI) performance longitudinally across clinical concussion recovery milestones through return to participation (RTP). We recruited 54 collegiate student-athletes, 27 with concussions and 27 matched controls (15 female and 12 male per group). Participants performed five trials of GI at baseline and again at five post-concussion clinical milestones: 1) Acute, the day clinical tests achieved baseline values on the 2) Balance Error Scoring System (BESS), 3) Immediate Post-Concussion Assessment and Cognitive Test ImPACT, 4) Asymptomatic, and 5) RTP Day. GI performance on six outcome measures (anterior/posterior and medial/lateral center of pressure displacements and velocities during the anticipatory postural adjustment [APA] phase and initial step length and velocity) with repeated-measures mixed model and pair-wise post hoc. A reliable change index (RCI) was calculated, and post-concussion participant's performance was compared to the RCI at milestones. There were significant interactions for APA posterior and lateral displacement, APA posterior velocity, step length, and step velocity. The post-hoc tests identified significant deficits across clinical milestones and at RTP for APA posterior and lateral displacement, step length, and step velocity. There were no post-hoc differences for any outcome measure in the control group. At RTP, 85.2-88.9% of concussion participants had at least one outcome measure which exceeded the 80% or 95% RCI. The primary finding of this study was persistent impairments in dynamic postural control, suggesting ongoing neurophysiological impairment despite clinical recovery. These results suggest that collegiate student-athletes may be RTP before neurophysiological recovery and potentially exposing themselves to elevated risk of recurrent concussion or subsequent musculoskeletal injury.

Gait Performance Is Associated with Subsequent Lower Extremity Injury following Concussion.

PURPOSE: The purpose was to examine gait characteristics between collegiate athletes who did and did not sustain a lower-extremity musculoskeletal (LEMSK) injury in the year after concussion. METHODS: Thirty-four NCAA collegiate athletes with diagnosed concussions were divided into two groups based on if they did (n = 16) or did not (n = 18) sustain a LEMSK in the year after concussion. Participants completed baseline testing before the start of the season and again at return to play postconcussion. Injuries were tracked using an electronic medical database. Participants were instrumented with three APDM Opal triaxial accelerometers and performed five single-task (ST) and five dual-task (DT) gait trials. Participants traversed a 10-meter walkway, turned around a specified endpoint, and returned to the original line. During DT, participants simultaneously walked and answered mini-mental style questions. A linear mixed-effects model assessed interactions and/or main effects between groups for gait speed, double support time, cadence, stride length, and cognitive accuracy. RESULTS: The LEMSK group walked slower (ST, 1.15 ± 0.10 m·s; DT, 1.01 ± 0.10 m·s) than the uninjured group (ST, 1.23 ± 0.11 m·s; DT, 1.10 ± 0.11 m·s) during both ST (P = 0.04) and DT (P = 0.03). The injury group spent longer in double support (ST, 20.19% ± 2.34%; DT, 21.92% ± 2.13%) than the uninjured group (ST, 18.16% ± 2.60%; DT, 20.00% ± 2.32%) during both ST (P = 0.02) and DT (P = 0.02). The injury group had a significantly lower cognitive accuracy (89.56% ± 6.48%) than the uninjured group (95.40% ± 7.08%) across time points (P = 0.02). CONCLUSIONS: There were significant differences in gait characteristics and cognitive accuracy between those who did and did not sustain a LEMSK injury after concussion. The LEMSK group demonstrated a conservative gait strategy both before and after their concussive injury.