Factors Associated with Symptom Resolution after Aerobic Exercise Intervention in Adolescent and Young Adults with Concussion

BACKGROUND

Aerobic exercise facilitates postconcussion symptom resolution at the group level, but patient-level characteristics may affect the likelihood of treatment efficacy.

PURPOSE

This study aimed to investigate demographic and clinical characteristics, which differentiate postconcussion aerobic exercise treatment efficacy from nonefficacy in the intervention arm of a randomized clinical trial.

METHODS

Adolescent and young adult participants initiated a standardized aerobic exercise intervention within 14 d of concussion, consisting of self-selected exercise for 100 min·wk -1 at an individualized heart rate (80% of heart rate induced symptom exacerbation during graded exercise testing). Treatment efficacy was defined as symptom resolution within 28-d postconcussion. Treatment efficacy and nonefficacy groups were compared on demographics, clinical characteristics, intervention adherence, and persistent symptom risk using the Predicting Persistent Postconcussive Problems in Pediatrics (5P) clinical risk score.

RESULTS

A total of 27 participants (16.1 ± 2.3 yr old; range, 11-21 yr; 52% female) began the intervention, with a mean of 9.5 ± 3.7 d after concussion; half ( n = 13; 48%) demonstrated treatment efficacy (symptom resolution within 28 d postconcussion). Those whose symptoms resolved within 28 d had significantly lower preintervention postconcussion symptom inventory scores (21.2 ± 13.2 vs 41.4 ± 22.2; P < 0.01), greater adherence to the intervention (77% vs 36%; P = 0.05), and longer average exercise duration (median [interquartile range], 49.7 [36.8-68.6] vs 30.4 [20.7-34.7] min; P < 0.01) than those whose symptoms lasted more than 28 d. Groups were similar in age, sex, timing of intervention, and preintervention 5P risk score.

CONCLUSIONS

A standardized aerobic exercise intervention initiated within 14 d of concussion demonstrated efficacy for approximately half of participants, according to our definition of treatment efficacy. This multisite aerobic exercise intervention suggests that lower symptom severity, higher intervention adherence, and greater exercise duration are factors that increase the likelihood of symptoms resolving within 28 d of concussion.

Postconcussion Moderate to Vigorous Physical Activity Predicts Anxiety Severity among Adolescent Athletes

PURPOSE

This study aimed to examine how moderate-to-vigorous physical activity (MVPA) during concussion recovery influences self-reported anxiety symptoms at follow-up assessment. We hypothesized that more MVPA after concussion would be associated with lower anxiety rating at follow-up.

METHODS

We performed a prospective study of participants aged 13-18 yr initially assessed within 14 d of diagnosed concussion. Participants rated concussion symptoms using the Post-Concussion Symptom Inventory and were provided a wrist-worn actigraphy device to track activity for 1 wk after assessment. At follow-up assessment, participants rated anxiety symptoms using the four-question Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety subscale. Each question ranged from 1 (never) to 5 (almost always), with an overall score range of 4-20. For univariable analysis, we calculated correlation coefficients between MVPA and PROMIS anxiety subscale scores. We then created a multiple linear regression model with follow-up PROMIS anxiety subscale score as the outcome and MVPA, sex, initial symptom severity, and preconcussion anxiety as predictors.

RESULTS

We enrolled and initially tested 55 participants, and 48 were included in the final analysis (age, 14.6±2.7 yr; 56% female; initial assessment, 7.3± 3.1 d; follow-up assessment, 42.0±29.7 d). We observed an inverse and low correlation between MVPA and follow-up PROMIS anxiety subscale T-scores ( r = -0.30, P = 0.04). Multivariable regression results indicated that MVPA ( β = -5.30; 95% confidence interval (CI), -10.58 to -0.01), initial Post-Concussion Symptom Inventory score ( β = 0.11; 95% CI, 0.03 to 0.19), and preconcussion anxiety ( β = 5.56; 95% CI, 0.12 to 11.0), but not sex ( β = -2.60; 95% CI, -7.14, to 1.94), were associated with follow-up PROMIS anxiety subscale T-scores.

CONCLUSIONS

After adjusting for covariates, more MVPA early after concussion predicted lower PROMIS anxiety subscale scores at follow-up. Although initial concussion symptom severity and preconcussion anxiety were also associated with follow-up PROMIS anxiety subscale score, MVPA represents a modifiable factor that may contribute to lower anxiety symptoms.

Variables associated with days of school missed following concussion: results from the Sport Concussion Outcomes in PEdiatrics (SCOPE) study

OBJECTIVE

To understand factors associated with missed academic time after concussion to improve support for patients. Our goal was to assess patient-specific predictors of total school time lost after pediatric/adolescent concussion.

STUDY DESIGN

We performed a prospective cohort study of children and adolescents (8-18 years of age) seen within 14 days of concussion from seven pediatric medical centers across the United States. We collected outcomes via the Concussion Learning Assessment & School Survey (CLASS) and constructed a multivariable predictive model evaluating patient factors associated with school time loss.

RESULTS

167 patients participated (mean age = 14.5 ± 2.2 years; 46% female). Patients were assessed initially at 5.0 ± 3.0 days post-injury and had a final follow-up assessment 24.5 ± 20.0 days post-concussion. Participants missed a median of 2 days of school (IQR = 0.5-4), and 21% reported their grades dropped after concussion. Higher initial symptom severity rating (β = 0.06, 95% CI = 0.03-0.08, p < 0.001) and perception of grades dropping after concussion (β = 1.37, 95% CI = 0.28-2.45, p = 0.01) were significantly associated with more days of school time missed after concussion. Those who reported their grades dropping reported missing significantly more school (mean = 5.0, SD = 4.7 days missed of school) than those who reported their grades did not drop (mean = 2.2, SD = 2.6 days missed of school; p < 0.001; Cohen's d = 0.87).

CONCLUSIONS

Children and adolescents reported missing a median of 2 days of school following concussion, and more missed school time after a concussion was associated with more severe concussion symptoms and perception of grades dropping. These findings may support recommendations for minimal delays in return-to-learn after concussion.

High magnitude exposure to repetitive head impacts alters female adolescent brain activity for lower extremity motor control

Contact and collision sport participation among adolescent athletes has raised concerns about the potential negative effects of cumulative repetitive head impacts (RHIs) on brain function. Impairments from RHIs and sports-related concussions (SRC) may propagate into lingering neuromuscular control. However, the neural mechanisms that link RHIs to altered motor control processes remain unknown. The purpose of this study was to isolate changes in neural activity for a lower extremity motor control task associated with the frequency and magnitude of RHI exposure. A cohort of fifteen high school female soccer players participated in a prospective longitudinal study and underwent pre- and post-season functional magnetic resonance imaging (fMRI). During fMRI, athletes completed simultaneous bilateral ankle, knee, and hip flexion/extension movements against resistance (bilateral leg press) to characterize neural activity associated with lower extremity motor control. RHI data were binned into continuous categories between 20 g - 120 g (defined by progressively greater intervals), with the number of impacts independently modeled within the fMRI analyses. Results revealed that differential exposure to high magnitude RHIs (≥90 g - < 110 g and ≥ 110 g) was associated with acute changes in neural activity for the bilateral leg press (broadly inclusive of motor, visual, and cognitive regions; all p < 0.05 & z > 3.1). Greater exposure to high magnitude RHIs may impair lower extremity motor control through maladaptive neural mechanisms. Future work is warranted to extend these mechanistic findings and examine the linkages between RHI exposure and neural activity as it relates to subsequent neuromuscular control deficits.

Concussion symptom presentation and clinical recovery among pediatric athletes: comparing concussions sustained during school and summer months

OBJECTIVE

We examined post-concussion symptom presentation, exercise, and sleep among pediatric athletes who sustained concussion during the school year vs. summer months.

METHODS

We evaluated athletes 6-18 years old within 21-days of concussion. They reported symptoms (Health and Behavior Inventory), with cognitive/somatic domain sub-scores calculated, and indicated if they had exercised or experienced sleep problems since injury. We grouped patients by injury season: summer months (June-August) vs. school year (September-May).

RESULTS

350 patients (14.4 ± 2.4 years old; 37% female; initial visit 8.8 ± 5.3 days post-concussion) were seen for care: 24% sustained a concussion during summer months, 76% during the school year. Lower cognitive (median = 7 [IQR = 1, 15] vs. 9.5 [4, 17]; p = 0.01), but not somatic (7 [2.5, 11] vs. 8 [4, 13]; p = 0.06), HBI scores were observed for patients injured during the summer. Groups were similar in proportion exercising (16% vs 17%) and endorsing sleep problems (29% vs 31%). After adjustments, sustaining a concussion during the summer predicted total (β=-3.43; 95%CI = -6.50, -0.36; p = 0.029) and cognitive (β = -2.29; 95%CI = -4.22, -0.36; p = 0.02), but not somatic (β=-1.46; 95%CI = -2.84, -0.08; p = 0.04), symptom severity.

CONCLUSION

Pediatric patients with concussion may present with greater cognitive symptoms during the school year, compared to summer months.

Recovery in Hip Range of Motion in Young Flexibility Athletes 1 Year After Periacetabular Osteotomy

Background: Periacetabular Osteotomy (PAO) is a well-established surgical intervention for the treatment of hip dysplasia. Purpose: Our primary objective was to assess whether a group of young flexibility athletes who underwent PAO for hip dysplasia recovered their pre-operative hip range of motion (ROM) within 1 year of surgery. Our secondary objective was to compare hip ROM recovery between a group of young flexibility athletes and a group of non-flexibility athletes who underwent PAO for hip dysplasia. Results: In our study, 100% of flexibility athletes regained preoperative hip external rotation at 1-year post-operation. This was also the first plane of motion to return to preoperative motion in flexibility athletes. A significantly higher percentage of non-flexibility athletes regained their preoperative hip internal rotation compared to flexibility athletes (100% compared to 54%; P = .02), but not flexion or external rotation at 1-year post-operation. Conclusion: Our findings may help providers to set expectations regarding the recovery of hip ROM in flexibility athletes who undergo PAO for hip dysplasia.Level of Evidence: Level IV.

A Multifaceted Approach to Interpreting Reaction Time Deficits After Adolescent Concussion

CONTEXT

Reaction time (RT) is a critical element of return to participation (RTP), and impairments have been linked to subsequent injury after a concussion. Current RT assessments have limitations in clinical feasibility and in the identification of subtle deficits after concussion symptom resolution.

OBJECTIVES

To examine the utility of RT measurements (clinical drop stick, simple stimulus-response, single-task Stroop, and dual-task Stroop) to differentiate between adolescents with concussion and uninjured control individuals at initial assessment and RTP.

DESIGN

Prospective cohort study.

SETTING

A pediatric sports medicine center associated with a regional tertiary care hospital.

PATIENTS OR OTHER PARTICIPANTS

Twenty-seven adolescents with a concussion (mean age = 14.8 ± 2.1 years; 52% female; tested 7.0 ± 3.3 days postconcussion) and 21 uninjured control individuals (mean age = 15.5 ± 1.6 years; 48% female).

MAIN OUTCOME MEASURE(S)

Participants completed the Post-Concussion Symptoms Inventory (PCSI) and a battery of RT tests: clinical drop stick, simple stimulus-response, single-task Stroop, and dual-task Stroop.

RESULTS

The concussion group demonstrated slower clinical drop stick (β = 58.8; 95% CI = 29.2, 88.3; P < .001) and dual-task Stroop (β = 464.2; 95% CI = 318.4, 610.0; P < .001) RT measures at the initial assessment than the uninjured control group. At 1-month follow up, the concussion group displayed slower clinical drop stick (238.9 ± 25.9 versus 188.1 ± 21.7 milliseconds; P < .001; d = 2.10), single-task Stroop (1527.8 ± 204.5 versus 1319.8 ± 133.5 milliseconds; P = .001; d = 1.20), and dual-task Stroop (1549.9 ± 264.7 versus 1341.5 ± 114.7 milliseconds; P = .002; d = 1.04) RT than the control group, respectively, while symptom severity was similar between groups (7.4 ± 11.2 versus 5.3 ± 6.5; P = .44; d = 0.24). Classification accuracy and area under the curve (AUC) values were highest for the clinical drop stick (85.1% accuracy, AUC = 0.86, P < .001) and dual-task Stroop (87.2% accuracy, AUC = 0.92, P < .002) RT variables at initial evaluation.

CONCLUSIONS

Adolescents recovering from concussion may have initial RT deficits that persist despite symptom recovery. The clinical drop stick and dual-task Stroop RT measures demonstrated high clinical utility given high classification accuracy, sensitivity, and specificity to detect postconcussion RT deficits and may be considered for initial and RTP assessment.

Concussion Symptoms and Neurocognitive Performance of Children and Adolescents on Antidepressants

INTRODUCTION/PURPOSE

There is a well-established association between pre-existing depression/anxiety and greater post-concussion symptom burden, but the potential impact of antidepressant medications has not been fully explored. The primary objective of this study was to compare pre-injury/baseline and post-injury 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 post-injury. 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 post-injury, athletes with depression/anxiety had mean total symptom scores that were more than double that of healthy controls regardless of antidepressant use. While there were no significant differences in neurocognitive performance at baseline, depression/anxiety was associated with small but significant decreases in post-injury 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.

Exercising More Than 150 min/wk After Concussion Is Associated With Sleep Quality Improvements

OBJECTIVE

To examine whether a high volume of aerobic exercise after concussion (>150 min/wk) is associated with improved sleep quality over a 1-month period. We hypothesized that more than 150 min/wk of exercise would be associated with improved sleep quality across concussion recovery.

DESIGN

Prospective cohort observational study.

SETTING

Sports medicine clinic.

PARTICIPANTS

Adolescents initially tested 8.4 ± 3.5 (range, 2-18) days postconcussion who returned for a follow-up assessment 34.3 ± 7.7 (range: 20-49) days postconcussion.

MAIN OUTCOME MEASURES

Participants completed the Pittsburgh Sleep Quality Index and the Post-Concussion Symptom Inventory. No specific exercise or sleep recommendations were given beyond what their treating physician provided. Between study visits, participants recorded exercise performed via wrist-worn actigraphy. We calculated average exercise minutes per week and grouped participants as those who exercised more than 150 min/wk versus those who exercised 150 min/wk or less.

RESULTS

Thirty-six adolescents participated. Fifteen (42%) recorded more than 150 min/wk of aerobic exercise (age = 14.0 ± 1.7 years; 47% female; mean = 5.6 ± 1.2 d/wk of exercise; mean = 49.2 ± 17.5 min/session), and 21 recorded 150 min/wk or less of aerobic exercise (age = 15.0 ± 1.9 years; 76% female; mean = 2.7 ± 1.6 d/wk of exercise; mean = 30.2 ± 7.8 min/session). There were no significant group differences in the proportion of those who self-reported beginning physical activity prior to enrollment (47% vs 33%; P = .42) or for initial sleep quality rating (8.0 ± 3.7 vs 8.6 ± 4.1; P = .67) or initial concussion symptom severity rating (34.9 ± 28.0 vs 42.6 ± 25.9; P = .40). The group that exercised more than 150 min/wk between visits demonstrated significantly greater median PSQI rating improvements than those who exercised 150 min/wk or less, with a large effect size noted (median change [interquartile range] = 5 [3, 7] vs 1 [0, 4]; P = .008; Cohen d = 0.96).

CONCLUSION

Current recommendations suggest that subsymptom aerobic exercise can be beneficial after concussion. Our findings indicate that an exercise volume of more than 150 min/wk led to greater sleep quality improvements than those who exercised below this level.

Ankle Sprain History Does Not Significantly Alter Single- and Dual-Task Spatiotemporal Gait Mechanics

CONTEXT

Single- and dual-task walking gait assessments have been used to identify persistent movement and cognitive dysfunction among athletes with concussions. However, it is unclear whether previous ankle sprain injuries confound these outcomes during baseline testing. The purpose of this study was to determine the effects of (1) ankle sprain history and (2) time since prior ankle sprain injury on single- and dual-task spatiotemporal gait outcomes and cognitive measures.

DESIGN

Cross-sectional study.

METHODS

We assessed 60 college Division-I athletes (31 with ankle sprain history; 13 females and 18 males, 19.3 [0.8] y; 29 with no ankle sprain history, 14 females and 15 males, 19.7 [0.9] y) who completed injury history forms and underwent concussion baseline testing. Athletes completed single- and dual-task gait assessments by walking back and forth along an 8-m walkway for 40 seconds. Athletes wore a smartphone with an associated mobile application on their lumbar spine to record spatiotemporal gait parameters and dual-task cognitive performance. Separate multivariate analyses of variance were used to assess the effects of ankle sprain injury history on spatiotemporal measures, gait variability, and cognitive performance. We performed a multivariate regression subanalysis on athletes who reported time since injury (n = 23) to assess temporal effects on gait and cognitive performance.

RESULTS

Athletes with and without a history of ankle sprains had comparable spatiotemporal and gait variability outcomes during single- (P = .42; P = .13) and dual-task (P = .75; P = .55) conditions. Additionally, ankle sprain injury history did not significantly influence cognitive performance (P = .35). Finally, time since ankle sprain did not significantly affect single- (P = .75) and dual-task gait (P = .69), nor cognitive performance (P = .19).

CONCLUSIONS

Ankle sprain injury history did not significantly alter spatiotemporal gait outcomes nor cognitive performance during this common clinical assessment. Future studies may consider including athletes with ankle sprain injury history during concussion assessments.

Utility of a Clinical Prediction Tool for Persisting Postconcussive Symptoms in a Multicenter Sample of Youth Athletes With Concussion: The Sport Concussion Outcomes in Pediatrics (SCOPE) Study

BACKGROUND

A validated clinical risk tool has been developed to identify pediatric and adolescent patients at risk of developing persisting symptoms after concussion, but has not been prospectively investigated within a sample of athletes seen after concussion by primary care sports medicine physicians and/or athletic trainers.

PURPOSE

To determine whether a validated clinical risk prediction tool for persistent postconcussive symptoms (PPCSs) predicted which patients would develop PPCSs when obtained within 14 days of concussion among a multicenter sample of adolescent athletes.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Pediatric and adolescent patients (8-18 years of age) from 7 pediatric medical centers and 6 secondary school athletic training facilities who were diagnosed with a concussion and presented ≤14 days after concussion were enrolled as part of the Sport Concussion Outcomes in Pediatrics (SCOPE) study during their initial visit and were followed until symptom resolution. Clinical risk scores (Predicting and Preventing Post-concussive Problems in Pediatrics [5P]) and total symptom severity were obtained using the Post-Concussion Symptom Inventory at the initial visit (mean, 4.9 ± 2.9 days after concussion). Participants were then compared based on symptom resolution time: PPCS group (≥28 days to symptom resolution) and no-PPCS group (<28 days). The authors assessed the odds of developing PPCSs based on the 5P risk score using a binary logistic regression model and the utility of the clinical risk prediction tool to identify total time to symptom resolution using a Cox proportional hazards model.

RESULTS

A total of 184 participants enrolled, underwent initial evaluation, and were followed until symptom resolution (mean age, 15.2 ± 2.1 years; 35% female). The mean time to symptom resolution across the entire sample was 17.6 ± 3.7 days; 16% (n = 30) of participants developed PPCS. Those in the PPCS group had significantly greater mean initial total 5P risk scores than those in the no-PPCS group (7.9 ± 1.7 vs 5.9 ± 2.3, respectively; P < .001). After adjustment for initial symptom severity, time to assessment, and assessment setting, a higher initial total 5P risk score was associated with a significantly greater odds of developing PPCSs (adjusted odds ratio, 1.49; 95% CI, 1.07-2.08; P = .019). Furthermore, a higher 5P risk score was significantly associated with longer total symptom resolution time (hazard ratio, 0.80; 95% CI, 0.74-0.88; P < .001).

CONCLUSION

In a multicenter sample of youth athletes seen in different outpatient health care settings, the 5P risk score accurately predicted which athletes may be at risk for developing PPCSs.

Changes in Quality of Life, Sleep, and Physical Activity During COVID-19: A Longitudinal Study of Adolescent Athletes

CONTEXT

The abrupt cessation of school and sport participation during the COVID-19 pandemic may have negative implications for adolescent mental health.

OBJECTIVES

To (1) compare mental, physical, and social health and behaviors during pandemic-related stay-at-home mandates with the same measures collected 1 to 2 years earlier and (2) evaluate the relationships between physical activity and sleep during the pandemic and changes in anxiety, fatigue, and peer relationships between assessment times.

DESIGN

Cohort study.

SETTING

Pediatric sports medicine center.

PATIENTS OR OTHER PARTICIPANTS

A total of 39 high school athletes (25 adolescent girls, 14 adolescent boys; age = 16.2 ± 0.9 years).

MAIN OUTCOME MEASURE(S)

Patient-Reported Outcome Measurement System anxiety, fatigue, and peer relationships short forms and the Pittsburgh Sleep Quality Index were completed twice (initial assessment in May 2018 or 2019, follow-up assessment in May or June 2020). Frequency and duration of physical activity and frequency of interaction with other individuals (family, peers, sport coaches, etc) were self-reported at follow-up assessment for the 2 weeks before school or sport closure and the 2 weeks before questionnaire completion.

RESULTS

Higher levels of anxiety (5.5 ± 4.0 versus 3.6 ± 3.4 points; P = .003) and fatigue (5.4 ± 3.7 versus 2.3 ± 2.5 points; P < .001) and worse sleep quality (6.6 ± 2.9 versus 4.3 ± 2.3 points; P < .001) were observed during the pandemic compared with previous assessments. Reductions in physical activity were noted between assessments (exercise duration: 86.4 ± 41.0 versus 53.8 ± 30.0 minutes; P < .001). Sleep quality but not physical activity during the pandemic predicted changes in fatigue (P = .03, β = 0.44 [95% CI = 0.06, 0.83]) and peer relationships (P = .01, β = -0.65 [95% CI = -1.16, -0.15]) from initial to follow-up assessment.

CONCLUSIONS

Mental and physical health declined during stay-at-home mandates compared with assessments 1 to 2 years earlier. Physical activity behaviors and sources of social interaction underwent changes after school and sport cessation. Sleep quality may have provided some protection against declining adolescent mental health during the pandemic, although this relationship requires further investigation.

Training volume recommendations and psychosocial outcomes in adolescent athletes

OBJECTIVES

Researchers have recommended that youth athletes limit their practice volume to the number of hours/week that they are old in years. We examined sport perceptions, burnout, anxiety, and depressive symptoms among youth athletes who did and did not report playing more hours/week of organized sports than their age.

METHODS

Uninjured athletes aged 13-18 years old completed questionnaires documenting demographics, sport participation volume, health and injury history, depressive symptoms, anxiety, burnout, and sport perceptions during a pre-participation physical examination. We grouped participants as those who reported more hours/week in organized sports than their age (exceeds age/volume recommendation) vs. those who reported equal/less hours/week in organized sports than their age (meets age/volume recommendation).

RESULTS

Of 161 participants, 21% (n = 33) were in the 'exceeds age/volume recommendation' group (age = 15.2 ± 1.3 years; 55% female; 18.7 ± 4.0 hours/week) and 79% (n = 128) were in the 'meets age/volume recommendation' group (age = 15.6 ± 1.2 years; 50% female; 10.2 ± 3.4 hours/week). A higher proportion of the 'exceeds age/volume recommendation' group agreed with the statement 'youth in my sport play too many games before college' than the 'meets age/volume recommendation' group (33% vs. 16%; p = 0.03). After adjusting for the effect of age, sport specialization level, and weight, exceeding age/volume recommendations was associated with the perception that youth in sports play too many games before college (aOR = 3.24; 95% CI = 1.26, 8.29; p = 0.01), while burnout (aOR = 0.99; 95% CI = 0.94, 1.06; p = 0.93), anxiety (aOR = 0.97; 95% CI = 0.84, 1.11; p = 0.65), and depressive symptoms (aOR = 0.90; 95% CI = 0.74, 1.10; p = 0.30) were not significantly related.

CONCLUSION

Athletes who spend more hours in sport than their age appear to perceive their competition load during youth sports to be excessive. Coaches and providers should monitor athlete's training hours and perceptions of competition load to offer support and potentially prevent burnout development.

Athlete Burnout Is Associated With Perceived Likelihood of Future Injury Among Healthy Adolescent Athletes

We examined perceived risk of future sports injury and athlete burnout among uninjured adolescent athletes. Uninjured high school athlete participants completed the Athlete Burnout Questionnaire (ABQ) and a questionnaire assessing attitudes toward likelihood of sustaining a future sport-related injury. We compared ABQ responses between injury risk perception groups: those who expected injury versus those who did not. Half of the participants reported a somewhat/very high likelihood of future sport-related injury (n = 98; 52% female; age = 15.3 ± 1.9 years), while the other half reported it was unlikely/not possible (n = 98; 45% female; age = 15.3 ± 1.3 years). A significantly greater proportion of those in the expected injury group reported a history of bone/muscle/ligament/tendon injury (56% vs 24%; P < .001). Those in the expected injury group reported higher athlete burnout scores (median = 28 [interquartile range = 25-34] vs 25 [23-30]; P = .002). Adolescent athletes who reported they were likely to experience a future injury in their sport also reported greater levels of burnout.

The association between sleep and physical activity with persisting postconcussion symptoms among adolescent athletes

BACKGROUND

Both sleep duration and physical activity following concussion may influence subsequent recovery. Objective measurement of sleep and physical activity behavior via wearable technology may provide insights into their association with concussion recovery.

OBJECTIVE

To determine whether sleep behavior (eg, duration, timing) and/or physical activity (steps/day, or exercise frequency, duration, intensity) in the first month after adolescent sports-related concussion are associated with developing persisting postconcussion symptoms (PPCS).

DESIGN

Case-control.

SETTING

Outpatient sports medicine clinic.

PARTICIPANTS

The study prospectively enrolled adolescent athletes who sustained a concussion (N = 49, age = 14.8 ± 1.8 years; 51% female) who were evaluated within 14 days of concussion (mean = 6.7 ± 2.7 days) and followed uvia sleep/physical activity monitoring for the subsequent 2 weeks.

MAIN OUTCOME MEASURES

Participants wore a monitor to track sleep (sleep time, wake time, and time spent awake in bed at night) and physical activity (average steps/day, exercise frequency, exercise duration) behavior for 2 weeks after initial assessment. Participants were followed until symptom resolution, and the main outcome of interest was development of PPCS (symptom duration >28 days). A multivariable logistic regression model was used to examine associations between physical activity and sleep behavior with PPCS.

RESULTS

Of the 49 participants, 47% (n = 23, mean symptom resolution = 57 ± 23 days post injury) developed PPCS and 53% (n = 26, mean symptom resolution = 15 ± 7 days post injury) did not. Univariable analysis showed that the PPCS group took fewer steps/day (7526 ± 2975 vs. 9803 ± 3786 steps/day; p = .02), exercised less frequently (2.5 ± 2.2 vs. 4.4 ± 2.1 days/week; p = .005), and spent more time in bed awake (1.2 ± 0.3 vs. 0.8 ± 0.3 h/night; p = .03) than the no PPCS group. Multivariable results indicated the odds of developing PPCS significantly increased with fewer exercise session/week (adjusted odds ratio = 1.96, 95% confidence interval = 1.09, 3.51, p = .024).

CONCLUSIONS

More exercise sessions that were longer than 15 minutes during concussion recovery was associated with a lower risk of developing PPCS, whereas sleep and other physical activity measures were not. Further studies regarding exercise duration and intensity are needed. Clinicians may consider advising patients to optimize sleep and physical activity during concussion recovery.

Influence of Personal and Injury-Related Factors Predicting Deficits in Quality of Life Domains Among Pediatric Athletes: Findings From the Sport Concussion Outcomes in Pediatrics Study

OBJECTIVE

To examine patient and injury factors that may predict quality of life (QoL) and symptom duration after concussion.

DESIGN

Prospective, longitudinal.

SETTINGS

Six children's hospital-based medical centers and 9 secondary school athletic training facilities.

PATIENTS

Pediatric patients (8-18 years) were enrolled as part of the Sport Concussion Outcomes in Pediatrics (SCOPE) study during their initial visit for a diagnosis of sport-related concussion.

INTERVENTIONS

Patients completed a medical history, the Postconcussion Symptom Inventory (PCSI), and Patient-Reported Outcomes Measurement Information System Pediatric Profile-25 (PROMIS-PP).

MAIN OUTCOME MEASURES

Eight predictor variables [age, sex, assessment time, loss of consciousness, amnesia and history of concussion, migraines, or attention-deficit hyperactivity disorder or (ADHD)] were assessed using regression models constructed for each dependent variable.

RESULTS

A total of 244 patients (15.1 ± 2.1 years, 41% female) were enrolled (mean = 5 ± 3 days after concussion; range = 1-14 days). Female sex, later initial assessment, and presence of amnesia were associated with lower QoL scores on several domains, whereas loss of consciousness was associated with higher QoL for fatigue. A history of migraines was associated with lower peer relationship QoL. Patients who subsequently developed persisting symptoms had lower mobility scores and higher anxiety, depressive symptom, fatigue, and pain interference scores.

CONCLUSIONS

Female sex, later clinic presentation, and amnesia were associated with a lower QoL related to mobility, anxiety, depressive symptoms, fatigue, and pain interference. Interestingly, previous concussion and preinjury ADHD diagnosis did not negatively impact postinjury QoL at the initial visit. Future studies should assess the influence of these factors on QoL at later postinjury time points using a concussion-specific outcomes instrument.

Early Moderate to Vigorous Physical Activity After Concussion Is Associated With Faster Symptom Resolution Time

CONTEXT

Early physical activity (PA) after concussion may promote symptom resolution. Prior studies have investigated exercise frequency/duration, yet precise PA intensity or volume required for optimal recovery requires further investigation. moderate to vigorous physical activity (MVPA) is beneficial for physical health. We investigated whether sedentary time, light activity time, MVPA time, or activity frequency in the weeks following concussion are associated with time to symptom resolution among adolescents.

DESIGN

Prospective cohort study.

METHODS

Adolescents 10-18 years of age were tested ≤14 days of concussion and followed until symptom resolution. At the initial visit, participants rated symptom severity and were provided wrist-worn activity trackers to monitor PA for the following week. PA behavior was categorized each day based on heart rate: sedentary (resting), light PA (50%-69% age-predicted max heart rate), and MVPA (70%-100% age-predicted max heart rate). Symptom resolution was defined as the date when participants reported cessation of concussion-like symptoms. Patients were not given specific PA instructions, though some may have received instructions from their physician.

RESULTS

Fifty-four participants were included in the study (54% female; mean age = 15.0 [1.8] y; initially assessed 7.5 [3.2] d after concussion). Female athletes recorded more sedentary time (900 [46] vs 738 [185] min/d; P = .01; Cohen d = 0.72), and less time in light PA (194.7 [64.5] vs 224 [55] min/d; P = .08; Cohen d = 0.48) and MVPA (23 [17] vs 38 [31] min/d; P = .04; Cohen d = 0.58) than male athletes. After adjusting for sedentary time, hours per day with >250 steps, sex, and initial symptom severity, more MVPA time was associated with faster symptom resolution time (hazard ratio = 1.016; 95% confidence interval, 1.001-1.032; P = .04).

CONCLUSION

Our findings offer preliminary insight into how varying PA intensities affect concussion recovery, as MVPA may be a higher intensity than what is typically prescribed in concussion care.

Validity and Reliability of Methods to Assess Movement Deficiencies Following Concussion: A COSMIN Systematic Review

BACKGROUND

There is an increased risk of subsequent concussion and musculoskeletal injury upon return to play following a sports-related concussion. Whilst there are numerous assessments available for clinicians for diagnosis and during return to play following concussion, many may lack the ability to detect these subclinical changes in function. Currently, there is no consensus or collated sources on the reliability, validity and feasibility of these assessments, which makes it difficult for clinicians and practitioners to select the most appropriate assessment for their needs.

OBJECTIVES

This systematic review aims to (1) consolidate the reliability and validity of motor function assessments across the time course of concussion management and (2) summarise their feasibility for clinicians and other end-users.

METHODS

A systematic search of five databases was conducted. Eligible studies were: (1) original research; (2) full-text English language; (3) peer-reviewed with level III evidence or higher; (4) assessed the validity of lower-limb motor assessments used to diagnose or determine readiness for athletes or military personnel who had sustained a concussion or; (5) assessed the test-retest reliability of lower-limb motor assessments used for concussion management amongst healthy athletes. Acceptable lower-limb motor assessments were dichotomised into instrumented and non-instrumented and then classified into static (stable around a fixed point), dynamic (movement around a fixed point), gait, and other categories. Each study was assessed using the COSMIN checklist to establish methodological and measurement quality.

RESULTS

A total of 1270 records were identified, with 637 duplicates removed. Titles and abstracts of 633 records were analysed, with 158 being retained for full-text review. A total of 67 records were included in this review; 37 records assessed reliability, and 35 records assessed the validity of lower-limb motor assessments. There were 42 different assessments included in the review, with 43% being non-instrumented, subjective assessments. Consistent evidence supported the use of instrumented assessments over non-instrumented, with gait-based assessments demonstrating sufficient reliability and validity compared to static or dynamic assessments.

CONCLUSION

These findings suggest that instrumented, gait-based assessments should be prioritised over static or dynamic balance assessments. The use of laboratory equipment (i.e. 3D motion capture, pressure sensitive walkways) on average exhibited sufficient reliability and validity, yet demonstrate poor feasibility. Further high-quality studies evaluating the reliability and validity of more readily available devices (i.e. inertial measurement units) are needed to fill the gap in current concussion management protocols. Practitioners can use this resource to understand the accuracy and precision of the assessments they have at their disposal to make informed decisions regarding the management of concussion.

TRAIL REGISTRATION

This systematic review was registered on PROSPERO (reg no. CRD42021256298).

Predicting Time to Evaluation After Pediatric Concussion: Factors Affecting Specialty Concussion Care

Background

The timing of clinical evaluation after pediatric concussion represents an important and potentially modifiable clinical milestone for diagnosis, selection of appropriate treatment pathways, and recovery prognosis. Patient demographics, socioeconomic status, or medical history may affect the time to the initial evaluation and subsequently influence recovery outcomes.

Purpose/Hypothesis

The purpose of this investigation was to evaluate the association of patient characteristics with the time to specialty evaluation after a concussion. It was hypothesized that patients with a history of concussion, a preexisting relationship with our specialty concussion program, or a higher ZIP code-based income estimate would present for care more quickly after a concussion than patients without these characteristics.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were patients with a concussion between 6 and 18 years old who were seen for care at a single sports medicine center between January 1 and December 31, 2019. Patient demographic, socioeconomic, injury, and clinical characteristics were collected through a retrospective review of the medical records. The primary outcome was the number of days between the date of the concussion and the patient's initial specialty evaluation.

Results

Overall, 220 patients (mean age, 14.4 ± 2.5 years; 46% female) were seen for care at a mean of 9.7 ± 5.6 days (range, 1-21 days) after concussion. A shorter time to specialty evaluation was associated with a history of concussion (β = -1.72 [95% CI, -3.24 to -0.20]; P = .03) and a prior clinical relationship with the treating clinical department (β = -1.85 [95% CI, -3.52 to -0.19]; P = .03). Referral by a primary care provider was associated with a longer time to evaluation (β = 3.86 [95% CI, 2.39-5.33]; P < .0001).

Conclusion

A history of concussion and having a preexisting clinical relationship with the deparment were associated with a shorter time to evaluation after concussion. Referral from a primary care physician was associated with a longer time to evaluation. Issues may exist in the propensity to access care after an injury, resulting in delays for initiating early treatment.

SalterHarris fractures in paediatric skiers and snowboarders

The incidence of paediatric fractures among winter sport athletes is not adequately studied. Our objective was to categorize fractures that occurred in paediatric skiers and snowboarders at a single ski resort. X-rays of 756 skiers/snowboarders aged 3-17 diagnosed with a fracture were categorized using the Salter-Harris (SH) classification. SH fractures were seen in 158 (21%) patients, with 123 (77%) being Type II. There were no significant differences between patients with a SH fracture and patients with a non-SH fracture for age, sex, snowboarding or skiing, mechanism of injury, terrain or the resort conditions on the day of injury. The most common mechanism of injury was falling onto snow while collisions resulted in more severe injuries. Compared to fractures without growth plate involvement, a higher proportion of SH fractures were seen in the humerus, radius, fibula and thumb; a lower proportion of SH fractures were observed at the tibia and clavicle.

Gymnastics and concussions: A retrospective chart review

OBJECTIVE

The purpose of this study was to investigate the clinical presentation (using PCSS), mechanism of injury, and recovery time of concussions sustained by gymnasts.

METHODS

A retrospective chart review was performed at Boston Children's Hospital: Sports Medicine Clinic. Patients were identified with the words 'gymnastics' and 'concussion.' Male and female gymnasts were included if they sustained a concussion during gymnastics training or competition and were between the ages of 6-22 years old. Sex, age, injury site, diagnosis, mechanism of injury, and time to presentation are described. Patients were compared during different types of gymnastics events for overall symptom burden, and individual symptom severities.

RESULTS

A total of 201 charts were assessed over a 6-year period and 62 patients met inclusion criteria. Floor exercise was the most common event at the time of injury. Loss of consciousness occurred in 20% of injuries. There was no significant association between the type of event and PCSS upon initial clinical visit (p = 0.82). A total of 13 gymnasts returned to the clinic for a subsequent injury after their concussion (Table 3).

CONCLUSIONS

Gymnasts are at risk for sport-related concussions. Most gymnasts reporting to a tertiary care center with the diagnosis of concussion sustain their injuries during floor exercise.

Double Vision and Light Sensitivity Symptoms are Associated With Return-to-School Timing After Pediatric Concussion

OBJECTIVE

To determine the association between academic time loss postconcussion and vision symptoms/impairments among pediatric patients.

DESIGN

Cross-sectional.

SETTING

Sports medicine clinic.

PATIENTS

Pediatric patients seen for care in a sports medicine clinic between the ages 6 and 18 years (n = 212; mean age = 14.3, SD = 2.4 years; 48% female) were evaluated within 21 days of concussion (mean = 9.8, SD = 5.7 days).

INDEPENDENT VARIABLE

Patients were grouped based on academic time loss (missed >5 days vs ≤5 days of school) at their initial postconcussion evaluation.

OUTCOME MEASURES

Patients rated concussion symptoms using the Health and Behavior Inventory (HBI) and underwent near point of convergence (NPC) testing. We compared groups on specific HBI symptom ratings of dizziness, blurry vision, seeing double, and light sensitivity, as well as NPC break and recovery point distances.

RESULTS

Two hundred twelve patients were included; n = 36 (17%) who reported missing >5 days of school. After adjusting for time since injury, parental education level, mechanism of injury, and preinjury anxiety, patients who reported missing >5 days of school had higher ratings of double vision (β = 0.27; 95% confidence interval [CI], 0.01-0.53; P = 0.04) and light sensitivity (β = 0.506; 95% CI, 0.061-0.951; P = 0.02), but not dizziness (β = 0.390; 95% CI, -0.047 to 0.827; P = 0.08) or blurry vision (β = 0.026; 95% CI, -0.352 to 0.404; P = 0.89).

CONCLUSION

Missing >5 days of school was associated with worse double vision and light sensitivity symptoms. Given the importance of vision in learning, assessing postconcussion vision symptoms may facilitate a successful return to school. Clinicians should assess a wide spectrum of vision-specific symptoms to ensure appropriate support during the return-to-school process.

Comparison of Braces for Treatment of Sever's Disease (Calcaneal Apophysitis) in Barefoot Athletes: A Randomized Clinical Trial

CONTEXT

Sever's disease (calcaneal apophysitis) is a common condition in youth athletes, including those who participate in barefoot sports. Health care professionals often recommend that young athletes with Sever's disease wear heel cups in their shoes while active, but barefoot athletes are unable to use heel cups.

OBJECTIVE

To compare the efficacy of 2 braces used by barefoot athletes with Sever's disease.

DESIGN

Randomized controlled clinical trial.

SETTING

Pediatric sports medicine clinic.

PATIENTS OR OTHER PARTICIPANTS

A total of 43 barefoot athletes aged 7 to 14 years were enrolled, and 32 completed the study (age = 10.3 ± 1.6 years; 29 girls, 3 boys).

INTERVENTION(S)

Participants were randomized to the Tuli's Cheetah heel cup (n = 16) or Tuli's The X Brace (n = 16) group for use during barefoot sports over the 3-month study period.

MAIN OUTCOME MEASURE(S)

Participants completed self-reported assessments after diagnosis (baseline) and 1, 2, and 3 months later. The primary outcome was the Oxford Ankle Foot Questionnaire for Children (OxAFQ-C) physical score (3 months postenrollment). The secondary outcomes were OxAFQ-C school or play and emotional scores and the visual analog scale pain score.

RESULTS

The percentage of time wearing the brace during barefoot sports was not different between the Cheetah heel cup and The X Brace groups (82% versus 64% of the time in sports; P = .08). At 3 months, we observed no differences for the OxAFQ-C physical (0.79 versus 0.71; P = .80; Hedges g = 0.06), school or play (0.94 versus 1.00; P = .58; Hedges g = 0.26), or emotional (1.00 versus 1.00; P = .85; Hedges g = 0.21) score. Visual analog scale pain scores during activities of daily living and sports were lower (better) at the 2- and 3-month time points than at baseline (P < .001).

CONCLUSIONS

Both groups demonstrated improvements in ankle and foot function across time, but no between-groups differences were seen at 3 months. Given these results, barefoot athletes with Sever's disease may consider using either brace with barefoot activity to help improve pain and functional status.

Link Between the Female Athlete Triad and Gymnastics-Related Injury in Retired Collegiate Gymnasts

OBJECTIVES

To compare gymnastics-related injuries between former collegiate gymnasts who did and did not report components of the female athlete triad (Triad) during college, including disordered eating or menstrual irregularity. We hypothesized that athletes reporting these 2 triad symptoms would have higher rates of time loss injury and injuries requiring surgery.

DESIGN

Retrospective case-control.

SETTING

Online survey.

PATIENTS

Four hundred seventy former collegiate gymnasts.

INTERVENTIONS

Athletes completed online survey distributed through social media.

MAIN OUTCOME MEASURES

Participants were grouped based on self-reported menstrual irregularity and disordered eating during college. We compared time loss injuries, injuries resulting in surgery, and injury locations between the groups using χ2 analyses.

RESULTS

Seventy percent (n = 328) of participants in this study reported a time loss college injury without surgery, and 42% (n = 199) reported an injury during college that required surgical treatment. A significantly greater proportion of gymnasts with only disordered eating reported a time loss gymnastics injury (without surgery) compared with those who reported only menstrual irregularity during college (79% vs 64%; P =0 .03). A significantly greater proportion of the disordered eating-only group reported a spine injury compared with the menstrual irregularity-only group (P = 0.007) and the group who reported neither menstrual irregularity nor disordered eating (P = 0.006).

CONCLUSIONS

College gymnasts who experienced disordered eating were more likely to experience a nonsurgical time loss injury while in college, as well as spine injury compared with those with menstrual irregularity. Sports medicine providers should be aware of the association between injuries and individual components of Triad in gymnasts beyond bone stress injuries.

Sleep Problems After Concussion Are Associated With Poor Balance and Persistent Postconcussion Symptoms

We examined the association of self-reported sleep problems with clinical measures of postural stability, memory performance, symptom burden, and symptom duration following youth concussion. Patients 6-18 years of age presenting ≤21 days postconcussion underwent a clinical evaluation including modified Balance Error Scoring System, single- and dual-task tandem gait, immediate and delayed recall, and symptom severity. We calculated time from injury until symptom resolution and determined the proportion of patients who developed persistent postconcussion symptoms, defined as a symptom duration >28 days postconcussion. We grouped patients based on whether they reported sleep problems at their postconcussion clinical evaluation and compared symptom-based and functional outcomes between groups. Of the 207 patients included, n = 97 (14.3 ± 2.9 years; 49% female; initial visit 10.2 ± 5.8 days postconcussion) reported sleep problems postconcussion and n = 110 (14.3 ± 2.4 years; 46% female; initial visit 9.3 ± 5.4 days postinjury) did not. Those reporting sleep problems postconcussion had significantly more modified Balance Error Scoring System errors than those without (8.4 ± 5.5 vs 6.7 ± 4.7; P = .01), but similar tandem gait and memory performance. A significantly greater proportion of those who reported sleep problems postconcussion experienced persistent postconcussion symptoms than those who did not (53% vs 31%; P = .004). After adjusting for time from concussion to clinical visit and preconcussion sleep problems, postconcussion sleep problems were associated with a 2 times greater odds of developing persistent postconcussion symptoms (adjusted odds ratio = 2.02, 95% CI = 1.01, 4.06; P = .049). Identifying sleep problems early following concussion may allow clinicians to implement targeted treatment recommendations to improve sleep and provide an optimal recovery environment.

Are Different Aged Youth Skiers and Snowboarders Experiencing Different Injury Characteristics?

INTRODUCTION

Skiing and snowboarding are popular winter sports with significant youth participation and inherent potential for injury. We investigated the relationship between age and injury characteristics exhibited by youth skiers and snowboarders.

METHODS

In this cross-sectional study, we investigated injury characteristics among youth skiers and snowboarders at a ski resort, examining the association between age and injury type. We compared injury characteristics among young children (aged 3-6 y), school-aged children (aged 7-14 y), and older adolescents (aged 15-17 y) using χ², and examined predictive variables for injuries at different anatomical locations using logistic regression.

RESULTS

Compared with snowboarding, skiing was associated with greater odds of lower extremity (adjusted odds ratio [aOR]=6.8, 95% confidence interval [CI]: 4.89, 9.47, P<0.001) and head/face/neck (aOR=1.63, 95% CI: 1.20, 2.21, P=0.002) injuries. Compared with skiing, snowboarding was associated with greater odds of upper extremity injury (aOR=5.9, 95% CI: 4.6, 7.6, P<0.001). Age group significantly affected injury mechanism (χ² [df=12, n=1129]=42.882, P<0.0001) and diagnosis (χ² [df=12, n=1129]=43.093, P<0.0001). Young child skiers had the highest proportion of injuries to the head/neck/face and lower extremities and a significantly higher proportion of collision injuries and fractures than older skiers. Young child skiers most frequently injured the lower leg/ankle, while older skiers most frequently injured the knee.

CONCLUSIONS

Youth skiers exhibited predominately lower extremity injuries, while snowboarders exhibited predominately upper extremity injuries. Age significantly affected injury mechanism and injury diagnosis in youth skiers. Specifically, younger skiers tended to suffer more fractures and collision injuries than older youth skiers.

High healing rate of stable femoral condyle osteochondritis dissecans in young patients placed in a hinged knee brace locked in extension: a retrospective study

We report the rate of stable femoral condyle osteochondritis dissecans (OCD) lesion healing in adolescents using a locked hinged knee brace for a minimum of 6 weeks or until pain free, followed by physical therapy. Patients aged 5-18 at the time of a primary diagnosis of femoral condyle OCD were reviewed. Patients who presented with an unstable lesion necessitating surgery, lacked follow-up >6 months after diagnosis or before symptoms resolution, or were noncompliant were excluded. We assessed progression to surgery, association between surgery and lesion size, lesion grade, symptoms, laterality, and patient factors. Lesion width and depth and condyle size were measured on X-ray and MRI, and the scaled size of the lesion relative to the condyle was calculated. Sixty-four patients were included: 12.5% (n = 8; 50% female; mean age = 12.5 ± 1.0 years) progressed to surgery and 87.5% (n = 56; 20% female; mean age=11.5 ± 1.9 years) healed. No significant effects were identified between groups. The surgical group compared to the non-surgical group was braced for a similar amount of time (72.6 ± 51.4 vs. 54.9 ± 23.2 days; P = 0.09), presented initially with a similar lesion size (322.5 ± 298.7 vs. 211.2 ± 178.4 mm2; P = 0.14), and had a similar proportion of Grade 1 lesions (63% vs. 85%; P = 0.11). Female sex (P = 0.04) and longer time in the brace (P = 0.04) were associated with progression to surgery.

Early physical activity after concussion is associated with sleep quality but not dizziness among adolescent athletes

OBJECTIVES

To assess the association between early physical activity and post-concussion sleep quality, dizziness, and postural stability among adolescents with concussion compared to uninjured controls.

DESIGN

Cross-sectional.

METHODS

Adolescents ages 13-18 years assessed within 14 days post-concussion and uninjured controls. Those with concussion reported if they participated in physical activity between the concussion and assessment. Participants completed the Dizziness Handicap Inventory, Pittsburgh Sleep Quality Index, and single/dual-task tandem gait.

RESULTS

We enrolled 34 participants with concussion (early physical activity: n = 10, age = 15.8 ± 1.6 years, 70% female; no physical activity: n = 24, age = 16.0 ± 1.3 years, 50% female) and 21 uninjured controls (age = 16.0 ± 1.8 years, 48% female). Compared to controls, the no physical activity group reported worse sleep quality (Pittsburgh Sleep Quality Index: 3.8 ± 2.7 vs 8.0 ± 4.9 points, p = 0.002) and single-task tandem gait time (13.7 ± 3.4 vs 21.2 ± 8.1 s, p = 0.0006), while the early physical activity group did not (Pittsburgh Sleep Quality Index: 3.8 ± 2.7 vs 5.8 ± 3.2 points, p = 0.38; single-task tandem gait: 13.7 ± 3.4 vs 19.0 ± 5.7 s, p = 0.08). Compared to controls, early/no physical activity groups reported worse dizziness (Dizziness Handicap Inventory: 2.0 ± 3.4 vs 22.9 ± 23.8 vs 27.4 ± 19.2 points, p < 0.0001). There were no significant between-group differences for dual-task tandem gait (24.1 ± 8.0 vs 24.8 ± 6.2 vs 26.6 ± 7.3 s, p = 0.57).

CONCLUSIONS

The no physical activity group reported worse sleep quality and slower single-task tandem gait than controls, while both groups reported similar sleep quality and tandem gait. Early physical activity may promote sleep quality and postural stability, or early physical activity may be a function of improved sleep and postural stability after concussion.

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.

Patient Characteristics Predictive of Immediate and Delayed Word Recall Performance Following Adolescent Concussion

Clinicians rely on objective concussion assessments that may be influenced by patient characteristics, creating difficulties in isolating the effect of concussion on patient function. The purpose of our study was to identify characteristics associated with performance on the Sport Concussion Assessment Tool 5th edition (SCAT5) 10-word recall test following adolescent concussion. We evaluated patients seen for care within 14 days of concussion (n=125; 15.2±1.6 years of age, range=11-18 years; 46% female; 6.9±3.4 days post-concussion). Patient demographic (age, sex, medical and concussion history, etc.), injury (timing of presentation, symptom severity, sport-type, etc.), and clinical test (Modified Balance Error Scoring System [mBESS], tandem gait) characteristics were assessed, in addition to SCAT5 immediate and delayed memory testing using the 10-word recall list. Immediate and delayed recall performance was significantly associated with concussion symptom burden and cognitive accuracy during tandem gait, although effect sizes were notably small. Specific variables such as age, sex, diagnosis of ADD/ADHD, and performance on other clinical assessments were not significantly associated with recall performance after controlling for covariates. Further, the 10-word recall list demonstrates specific advantages over previously used 5-word lists by way of decreased ceiling effects and reduced interference of inherent patient characteristics.

Relationship and Latent Factors Between Clinical Concussion Assessments and the Functional Standardized Assessment of Reaction Time (StART)

OBJECTIVE

To examine the relationships and latent factors within the Standardized Assessment of Reaction Time (StART), and between StART and current clinical assessments.

DESIGN

Cross-sectional study.

SETTING

Clinical medicine facility.

PARTICIPANTS

Eighty-nine healthy collegiate student-athletes (63% male, age: 19.5 ± 0.9 years, 28% ≥1 concussion history).

ASSESSMENT OF RISK FACTORS

Student-athletes completed StART and clinical assessments during preinjury testing.

MAIN OUTCOME MEASURES

Standardized Assessment of Reaction Time consisted of 3 conditions (standing, single-leg balance, cutting) under 2 cognitive states (single task and dual task) for 3 trials each condition. Clinical assessments were the Sport Concussion Assessment Tool (SCAT) symptom checklist, Standardized Assessment of Concussion (SAC), tandem gait (single task and dual task), and Immediate PostConcussion Assessment and Cognitive Testing (ImPACT). We used Pearson- r correlation coefficients and exploratory factor analysis (EFA) to examine relationships and latent factors between StART and clinical assessments.

RESULTS

Null to moderate correlations presented among the StART outcomes (r range: 0.06-0.70), and null to small correlations between StART and clinical assessments (r range: -0.16 to 0.34). The three-factor EFA for solely StART explained 70.6% total variance: functional movement (cutting), static dual-task (standing and single-leg balance), and static single task (standing and single-leg balance). The five-factor EFA for StART and clinical assessments explained 65.8% total variance: gait (single-task and dual-task tandem gait), functional movement (StART single-task and dual-task cutting), static dual-task (StART standing, single-leg balance), neurocognitive (ImPACT verbal memory, visual memory, visual-motor speed), and static single task (StART standing, single-leg balance). No other outcomes met the factor loading threshold.

CONCLUSIONS

StART displayed 3 distinct categories and had minimal redundancy within its subtests. StART did not meaningfully correlate with clinical assessments, suggesting that StART provides unique information by examining more functional, reactive movement.

Sport specialization, sleep, fatigue, and psychosocial ratings: do highly specialized athletes differ from their less specialized peers?

OBJECTIVES

To determine if sleep quality, fatigue, anxiety, depressive symptoms, or perceptions of sport participation differ between high-, moderate-, and low-specialized high school athletes with or without prior injuries.

METHODS

During pre-participation physical examinations (PPE), high school athletes completed questionnaires on sport specialization level, history of time-loss orthopedic injury, perceptions of sport participation, as well as sleep quality (Pittsburgh Sleep Quality Index (PSQI)), fatigue, anxiety, and depressive symptoms (Patient-Reported Outcomes Measurement Information System (PROMIS®)). Athletes were grouped according to sport specialization level and history of prior time-loss orthopedic injury.

RESULTS

A total of 186 athletes completed the study: 49% (n = 92; mean age = 15.3 ± 2.0 yrs; 50% female) were low specialized, 34% (n = 64; mean age = 15.3 ± 1.3 yrs; 47% female) were moderately specialized, and 16% (n = 30; mean age = 15.7 ± 1.1 yrs; 57% female) were highly specialized. Groups were similar for demographics, training volume, and injury history. Compared to the moderate-specialization group, highly specialized athletes reported higher levels of fatigue (3.1 ± 3.7 vs. 1.5 ± 2.2; p = 0.02), anxiety (3.6 ± 4.1 vs. 1.8 ± 2.6; p = 0.02), and depressive symptoms (2.4 ± 4.0 vs. 0.8 ± 2.0; p = 0.02). No differences in psychometric ratings, sleep quality, or perceptions of sport participation were observed between the low/moderate- or low/high-specialization groups. We did not observe any significant differences between groups who did and did not report a history of prior time-loss orthopedic injury.

CONCLUSIONS

Highly specialized high school athletes report higher levels of fatigue, more anxiety symptoms, and more depressive symptoms than their moderately specialized peers, despite no differences in training volume or injury history. Low specialized athletes did not differ from moderately specialized or highly specialized athletes in the aforementioned domains, and there were no differences in sleep quality across specialization groups. These findings add to the current body of literature on early sport specialization by illustrating the distinctive psychosocial implications of sport specialization and demonstrating the need for further prospective research.

Eye Tracking Metrics Differences among Uninjured Adolescents and Those with Acute or Persistent Post-Concussion Symptoms

SIGNIFICANCE

Eye tracking assessments that include pupil metrics can supplement current clinical assessments of vision and autonomic dysfunction in concussed adolescents.

PURPOSE

This study aimed to explore the utility of a 220-second eye tracking assessment in distinguishing eye position, saccadic movement, and pupillary dynamics among uninjured adolescents, those with acute post-concussion symptoms (≤28 days since concussion), or those with persistent post-concussion symptoms (>28 days since concussion).

METHODS

Two hundred fifty-six eye tracking metrics across a prospective observational cohort of 180 uninjured adolescents recruited from a private suburban high school and 224 concussed adolescents, with acute or persistent symptoms, recruited from a tertiary care subspecialty concussion care program, 13 to 17 years old, from August 2017 to June 2021 were compared. Kruskal-Wallis tests were used, and Bonferroni corrections were applied to account for multiple comparisons and constructed receiver operating characteristic curves. Principal components analysis and regression models were applied to determine whether eye tracking metrics can augment clinical and demographic information in differentiating uninjured controls from concussed adolescents.

RESULTS

Two metrics of eye position were worse in those with concussion than uninjured adolescents, and only one metric was significantly different between acute cases and persistent cases. Concussed adolescents had larger left and right mean, median, minimum, and maximum pupil size than uninjured controls. Concussed adolescents had greater differences in mean, median, and variance of left and right pupil size. Twelve metrics distinguished female concussed participants from uninjured; only four were associated with concussion status in males. A logistic regression model including clinical and demographics data and transformed eye tracking metrics performed better in predicting concussion status than clinical and demographics data alone.

CONCLUSIONS

Objective eye tracking technology is capable of quickly identifying vision and pupillary disturbances after concussion, augmenting traditional clinical concussion assessments. These metrics may add to existing clinical practice for monitoring recovery in a heterogeneous adolescent concussion population.

Socioeconomic status and injury history in adolescent athletes: Lower family affluence is associated with a history of concussion

Background

While healthcare and health outcome disparities have been studied across a variety of different injuries, their relation to concussion incidence and management are relatively understudied.

Aim

The aim of this study was to evaluate the association between history of concussion or musculoskeletal injury, and family affluence and/or school-level measures of socioeconomic status.

Methods

We conducted a cross-sectional study of adolescent athletes in a local school district. Adolescent athletes (n = 192; mean age = 15.3, SD = 1.6 years; 49% female), who presented for a pre-participation physical evaluation reported concussion and injury history, and family affluence scale (FAS) scores. We also examined the percent of students on free/reduced lunch at each school compared to state averages. Independent variables, individual FAS score and school-based marker of socioeconomic status, were compared between those with and without a history of concussion and time-loss musculoskeletal injury.

Results

Of the participants, 40 (21%) reported a history of concussion. Athletes with a concussion history had significantly lower FAS scores than athletes without a history of concussion (mean difference = 0.7, 95%CI = 0.1, 1.4; P = 0.027). There was no significant difference in FAS scores between those with and without a history of time-loss musculoskeletal injury (mean difference = 0.0, 95% CI = -0.5, 0.5; P = 0.97). Athletes with a history of concussion had a higher proportion of a prior time-loss musculoskeletal injury (68% vs. 32%; P < 0.001). After adjusting for age, school free-reduced lunch rate, and history of musculoskeletal injury, a lower FAS score was associated with concussion history (adjusted odds ratio = 0.79; 95% CI = 0.64, 0.96; P = 0.019). Concussion and musculoskeletal injury were not associated with school-level markers of socioeconomic status.

Conclusion

Lower individual measures, but not school-level measures, of socioeconomic status were associated with a history of concussion in our sample of adolescent athletes.

Relevance for Patients

Enhance providers' understanding of how socioeconomic factors may impact concussion history and empower providers to adequately screen for and provide concussion education to mitigate disparities.

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.

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.

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; β = -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; β = -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.

Postconcussion Dizziness Severity Predicts Daily Step Count during Recovery among Adolescent Athletes

PURPOSE

Physical activity (PA) after concussion is an important aspect of appropriate clinical management. However, symptoms or functional deficits may reduce patient propensity toward PA, thereby negatively affecting recovery. Our purpose was to examine whether postconcussion dizziness, total symptom severity, or postural stability predicts PA level in the 2 wk after initial evaluation.

METHODS

We evaluated adolescent athletes within 14 d of concussion on assessments of symptoms, dizziness, and postural stability. Athletes were provided an activity monitor to track PA for 2 wk after the evaluation. Our primary outcome was step count (mean steps per day). Potential predictor variables included sex, Post-Concussion Symptom Inventory (PCSI) total symptom severity, individual PCSI ratings of dizziness and balance impairment, and postural stability assessments (single- and dual-task tandem gait, modified Balance Error Scoring System). To examine predictors of PA, we calculated correlation coefficients between steps per day and each potential predictor and included significantly correlated variables in a multivariable regression model.

RESULTS

Participants were ages 12-18 yr (n = 35, 15.2 ± 1.7 yr, 49% female) and initially evaluated 7.3 ± 3.0 d after concussion. Upon univariable evaluation, PCSI dizziness rating (Pearson R = -0.49, P = 0.003) and sex (mean difference, 2449 steps per day; P = 0.05) were associated with steps per day. Within the multivariable regression analysis, PCSI dizziness rating (β = -1035; 95% confidence interval, -191 to -1880; P = 0.018), but not sex, predicted average steps per day in the 2 wk after initial evaluation.

CONCLUSIONS

Self-reported dizziness, but not overall symptom severity or postural stability, assessed within 14 d of concussion predicted daily step count in the subsequent 2 wk. Given the importance of PA for concussion recovery, treating acute postconcussion dizziness can potentially reduce a barrier to PA and improve recovery trajectories.

Early Sport Specialization and Past Injury in Competitive Youth Rock Climbers

INTRODUCTION

Sport specialization has been shown to have negative effects on athletes but has not been studied within rock climbing. This study seeks to evaluate the proportion and impact of specialization in pediatric climbers.

METHODS

Climbers (ages 8-18 y) were recruited from throughout the United States to complete a 1-time survey regarding climbing experience, training patterns, and injury history. The main outcome of proportion of climbers suffering an injury was assessed within the last 12 mo and within their entire climbing experience (defined as "lifetime" injury). Early specialization was defined as exclusive participation in climbing, with training for >8 mo‧y^-1, prior to age 12 y (late specialization if after age 12 y).

RESULTS

Participants (n=111, 14±3 y [mean±SD], 69 females) were high-level climbers. Fifty-five percent of participants specialized in climbing, and 69% of those specialized early. Hand and ankle injuries occurred most commonly. Seventy-eight percent of late specialized climbers had a lifetime injury. Late specialized climbers were 1.6 times (95% CI: 1.1-2.3) more likely than early specialized climbers to have had a lifetime injury and 1.8 times (95% CI: 1.1-2.8) more likely to have had an injury in the last 12 mo. No difference in overuse injuries was found between specialization groups.

CONCLUSIONS

Early specialization is common among youth climbers but was not associated with an increase in injuries. Late specialization was associated with a higher likelihood of having had a climbing injury in the last 12 mo and during an entire climbing career.

Prediction of quadriceps tendon-patellar bone autograft diameter in adolescents with 2-dimensional magnetic resonance imaging and anthropometric measures

OBJECTIVES

This study evaluates the correlation between the bone end and soft tissue end of the quadriceps tendon-patellar bone autograft (QPA) size and pre-operative MRI measurements of the quadriceps tendon along sections to be included in the graft harvest in adolescents. We also assessed association between graft diameter and anthropometric measures (height, weight, and BMI), age, and sex.

METHODS

Patients (10-18 years) who underwent QPA ACL reconstruction and had a pre-operative MRI were considered for inclusion. Age, height, and weight, tibial and femoral side graft diameter, and patellar bone block dimensions were collected. Using a pre-operative 2D sagittal plane MRI, we measured the quadriceps at 10-mm increments above the patella, up to 40 mm. We assessed correlation between the bone-end graft diameter and the AP measure at 10 mm above the patella, and correlation between the soft-tissue end graft diameter and the most proximal AP measure.

RESULTS

A total of 103 patients were included. A significant correlation between the soft-tissue side graft diameter and most proximal AP measurement was observed (r_s = 0.51; p < 0.001). However, measurements significantly underestimated the soft-tissue end graft diameter (9.6 ± 0.8 vs. 7.4 ± 1.1; p < 0.001). There was no correlation between the bone-end graft diameter and AP measurement 10 mm above the patella. Anthropometric measures were not associated with graft size. Skeletal maturity was associated with smaller graft size (p = 0.08).

CONCLUSION

Soft-tissue end graft diameter is associated with the AP measure of the quadriceps at 20-40 mm above the superior pole of the patella.

An 8-Week Neuromuscular Training Program After Concussion Reduces 1-Year Subsequent Injury Risk: A Randomized Clinical Trial

BACKGROUND

Existing data suggest that after concussion, athletes experience an increased risk of subsequent injury. Exploring methods that may reduce injury risk after successful postconcussion return to play may lead to new treatment approaches.

PURPOSE

To examine the efficacy of a neuromuscular training (NMT) intervention on acute sports-related time-loss injury over the subsequent year relative to standard of care.

STUDY DESIGN

Randomized clinical trial; Level of evidence, 1.

METHODS

A total of 27 youth athletes were assessed initially postconcussion (median, 7 days postconcussion; interquartile range [IQR], 5-10) and after return-to-play clearance (median, 40 days postconcussion; IQR, 15-52). After return-to-play clearance, they were randomly assigned to NMT intervention (n = 11; mean ± SD age, 14.7 ± 1.7 years; 36% female) or standard of care (n = 16; mean ± SD age, 15.3 ± 1.8 years; 44% female). The intervention (duration, 8 weeks; frequency, 2 times per week) included guided strength exercises with landing stabilization focus. Standard of care received no recommendations. For the subsequent year, athletes prospectively completed a monthly log of sports-related injuries and organized sports competitions.

RESULTS

During the first year after postconcussion return-to-play clearance, sports-related time-loss injuries were more common among standard of care relative to NMT intervention (75% [95% CI, 48%-93%] vs 36% [95% CI, 11%-69%]). After adjusting for age and sex, the hazard of subsequent injury in the standard-of-care group was 3.56 times (95% CI, 1.11-11.49; P = .0334) that of the NMT intervention group. Sports participation was similar between NMT intervention and standard of care during the year-long monitoring period (hours of organized sports per month; median, 12 [IQR, 2.6-32.1] vs 15.6 [IQR, 3.5-105.9]; P = .55). The age- and sex-adjusted incidence of injuries was 10.2 per 1000 competitive exposures (95% CI, 3.7-28.4) in the standard-of-care group as opposed to 3.4 per 1000 (95% CI, 0.9-13.4) in the NMT intervention group. After adjusting for age and sex, incidence of injuries was higher for standard of care vs NMT intervention (rate ratio, 2.96 [95% CI, 0.89-9.85]; P = .076).

CONCLUSION

Although preliminary, our findings suggest that an NMT intervention initiated after return-to-play clearance may significantly reduce sports-related time-loss injuries over the subsequent year.

REGISTRATION

NCT03917290 (ClinicalTrials.gov identifier).

Proteomic Discovery of Noninvasive Biomarkers Associated With Sport-Related Concussions

BACKGROUND AND OBJECTIVES

Sport-related concussions affect millions of individuals across the United States each year, and current techniques to diagnose and monitor them rely largely on subjective measures. Our goal was to discover and validate objective, quantifiable noninvasive biomarkers with the potential to be used in sport-related concussion diagnosis.

METHODS

Urine samples from a convenience series of healthy control collegiate athletes who had not sustained a concussion and athletes who sustained a concussion as diagnosed by a sports medicine physician within 7 days were collected prospectively and studied. Participants also completed an instrumented single-task gait analysis as a functional measure. Participants were recruited from a single collegiate athletic program and were ≥18 years of age and were excluded if they had a concomitant injury, active psychiatric conditions, or preexisting neurologic disorders. Using Tandem Mass Tags (TMT) mass spectroscopy and ELISA, we identified and validated urinary biomarkers of concussion.

RESULTS

Forty-eight control and 47 age- and sex-matched athletes with concussion were included in the study (51.6% female, 48.4% male, average age 19.6 years). Participants represented both contact and noncontact sports. All but 1 of the postconcussion participants reported experiencing symptoms at the time of data collection. Insulin-like growth factor 1 (IGF-1) and IGF binding protein 5 (IGFBP5) were downregulated in the urine of athletes with concussions compared to healthy controls. Multivariable risk algorithms developed to predict the probability of sport-related concussion showed that IGF-1 multiplexed with single-task gait velocity predicts concussion risk across a range of postinjury time points (area under the curve [AUC] 0.786, 95% confidence interval [CI] 0.690-0.884). When IGF-1 and IGFBP5 are multiplexed with single-task gait velocity, they accurately distinguish between healthy controls and individuals with concussion at acute time points (AUC 0.835, 95% CI 0.701-0.968, p < 0.001).

DISCUSSION

These noninvasive biomarkers, discovered in an objective and validated manner, may be useful in diagnosing and monitoring sport-related concussions in both acute phases of injury and several days after injury.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT02354469 (submitted February 2015, first patient enrolled August 2015).

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that urinary IGF-1 and IGFBP5 multiplexed with single-task gait velocity may be useful in diagnosing sport-related concussion.

Objective Eye Tracking Metrics of Vision and Autonomic Dysfunction Distinguish Adolescents With Acute Concussion and Those with Persistent Post-Concussion Symptoms from Uninjured Controls

OBJECTIVE

To explore the utility of an eye-tracking assessment in distinguishing binocular alignment, saccadic movement, and pupillary dynamics among uninjured adolescents, acute cases (= 28 days since concussion), and persistent cases (>28 days since concussion).

BACKGROUND

Visual and autonomic system disturbances are common sequelae of concussion. Quantification of visual and autonomic dysfunction via an eye tracking device could provide an objective method of acute diagnosis and subacute identification of ongoing injury.

DESIGN/METHODS

We compared 347 eye tracking metrics, derived from a 220 seconds eye-tracking assessment, among 132 uninjured adolescents (mean age: 15.3, 56.2% female), 110 acute cases (mean days since injury: 12.5, mean age: 15.4, 46.4% female), and 95 persistent cases (mean days since injury: 53.6, mean age: 15.4, 70.2% female) using Kruskal-Wallis tests with Bonferroni corrections to account for multiple comparisons.

RESULTS

Nine eye-tracking metrics were significantly associated with injury status. One measure of binocular alignment (acute v. control: p = 0.003, persistent v. control: p = 0.001) and one measure of saccadic movement (acute v. persistent: p = 0.03, acute v. control: p = 0.03, persistent v. control: p < 0.001) were worse in cases. Cases had larger left and right mean and median pupil size than uninjured adolescents (acute v. control, p < 0.001; persistent v. control, p < 0.001). Cases had greater differences in mean (acute v. control: p < 0.001, persistent v. control: p < 0.001), median (acute v. control, p < 0.001, persistent v. control, p = 0.003), and variance of (acute v. control: p < 0.001, persistent v. control: p < 0.001) left and right pupil size. Eight of these metrics distinguished female cases from uninjured adolescents, but similar differences were not observed in male participants.

CONCLUSIONS

Objective eye tracking technology can identify vision and pupillary disturbances after concussion. These metrics could be integrated into clinical practice to monitor recovery in a heterogeneous adolescent concussion population and may identify sex-specific differences in autonomic dysfunction.

Examining Initial Post-Concussion Dizziness and Postural Stability as Potential Recovery Predictors

OBJECTIVE

To examine the association between acute post-concussion dizziness, initial symptom severity, and postural stability with time to symptom resolution among adolescents.

BACKGROUND

Identifying early post-concussion symptoms and functional deficits that predict symptom resolution can guide treatment strategies. Dizziness is among the most common concussion symptoms, and existing literature investigating the association between dizziness and recovery time is mixed.

DESIGN/METHODS

Participants underwent initial evaluation = 14 days post-concussion, and self-reported symptom severity using the Post-Concussion Symptom Inventory (PCSI). We used PSCI dizziness ratings to group participants: a difference between current and pre-injury dizziness ≥3 = dizzy; difference <3 = not dizzy. We evaluated postural stability using modified Balance Error Scoring System (mBESS) and tandem gait (TG). Patients were followed until symptom resolution, and our primary outcome of interest was time from concussion to symptom resolution. Using a univariable Cox proportional hazard model, we examined the association of dizziness and symptom resolution time. We then used a multivariable Cox proportional hazard model to adjust for variables that differed between groups.

RESULTS

We examined 89 participants, grouped as dizzy (n = 34; age = 14.7 ± 2.7 years; 7.1 ± 3.4 days post-injury; symptom resolution time = 40.8 ± 5.7 days) or not dizzy (n = 55; age = 14.4 ± 2.3 years; 7.2 ± 3.1 days post-injury; symptom resolution time = 23.3 ± 3.2 days). Upon univariable examination, dizziness was independently associated with symptom resolution time (HR = 0.49; 95% CI: 0.28, 0.83; p = 0.009). After adjusting for potential confounding variables (initial symptom severity, mBESS tandem stance errors, TG time, and loss of consciousness) multivariable model results indicated initial symptom severity was the only variable associated with symptom resolution time (HR = 0.98; 95% CI: 0.96, 0.997; p = 0.025).

CONCLUSIONS

Total symptom severity, but not dizziness or postural stability, was significantly associated with symptom resolution time among adolescents following concussion. Individuals with moderate to severe post-concussion dizziness had higher average symptom scores indicating self-reported dizziness should be interpreted in the context of total concussion symptom burden.