Static and Dynamic Cognitive Performance in Youth and Collegiate Athletes With Concussion.

OBJECTIVE: To determine if individuals with a concussion demonstrate altered cognitive performance while standing still or while walking relative to uninjured controls. DESIGN: Cross-sectional. SETTING: Sports-medicine clinic. PARTICIPANTS: Youth and collegiate athletes diagnosed with a concussion, assessed within 10 days of injury, and a group of uninjured control subjects. INDEPENDENT VARIABLES: Concussion and control groups. MAIN OUTCOME MEASURES: Participants stood still for 30 seconds while completing a cognitive task (spelling words backward, serial subtraction, or reverse month recitation) and completed a similar set of cognitive tasks while walking. Our primary outcome variables were (1) overall cognitive task performance (accuracy) and (2) the total number of task items completed during testing (completion rate) during standing and walking conditions. RESULTS: One hundred ninety-one participants completed the study: 94 with concussion (tested mean = 5.1 ± 2.9 days postconcussion; 51% female; mean age = 17.1 ± 3.3 years) and 97 control subjects (40% female; mean age = 17.5 ± 2.1 years). The concussion group completed significantly fewer responses than the control group while standing still (37.3 ± 14.5 vs 45.1 ± 17.6 responses; P = 0.03) and while walking (22.7 ± 7.5 vs 33.6 ± 13.4 responses; P < 0.001). They were also significantly less accurate at spelling words backward (81.2 ± 28.6% correct vs 89.8 ± 15.0% correct; P = 0.049) and reciting months in reverse order (95.8 ± 10.4% correct vs 98.2 ± 4.2% correct; P = 0.034) while walking. CONCLUSIONS: Athletes displayed lower cognitive task accuracy rates after concussion compared with control subjects during backward spelling and reverse month recitation tasks while walking but similar levels of accuracy while standing. Assessment of cognitive performance during dynamic tasks may be a clinically viable method to evaluate post-concussion deficits.

Reliability of Objective Eye-Tracking Measures Among Healthy Adolescent Athletes.

OBJECTIVE: To determine the test-retest correlation of an objective eye-tracking device among uninjured youth athletes. DESIGN: Repeated-measures study. SETTING: Sports-medicine clinic. PARTICIPANTS: Healthy youth athletes (mean age = 14.6 ± 2.2 years; 39% women) completed a brief, automated, and objective eye-tracking assessment. INDEPENDENT VARIABLES: Participants completed the eye-tracking assessment at 2 different testing sessions. MAIN OUTCOME MEASURES: During the assessment, participants watched a 220-second video clip while it moved around a computer monitor in a clockwise direction as an eye tracker recorded eye movements. We obtained 13 eye movement outcome variables and assessed correlations between the assessments made at the 2 time points using Spearman's Rho (rs). RESULTS: Thirty-one participants completed the eye-tracking evaluation at 2 time points [median = 7 (interquartile range = 6-9) days between tests]. No significant differences in outcomes were found between the 2 testing times. Several eye movement variables demonstrated moderate to moderately high test-retest reliability. Combined eye conjugacy metric (BOX score, rs = 0.529, P = 0.008), the variance of the ratio for both eye movements in the horizontal (rs = 0.497, P = 0.013) and vertical (rs = 0.446; P = 0.029) movement planes along the top/bottom of the computer screen, and the variance of the left and right eye movement along the bottom segment of the computer screen (rs = 0.565; P = 0.004) each demonstrated moderate between-test correlations. CONCLUSIONS: Automated and quantitative eye movement and conjugacy metrics provide relatively stable measurements among a group of healthy youth athletes. Thus, their inclusion as a visual tracking metric may be complementary to other visual examination techniques when monitoring concussion recovery across time.

Exercise in the first week following concussion among collegiate athletes: Preliminary findings.

OBJECTIVES: Our purpose was to examine the association between exercise after concussion with symptom severity, postural control, and time to symptom-resolution. DESIGN: Longitudinal cohort. METHODS: Collegiate athletes (n = 72; age = 20.2 ±â€¯1.3 years; 46% female) with concussion completed a symptom questionnaire at initial (0.6 ±â€¯0.8 days post-injury) and follow-up (2.9 ±â€¯1.4 days post-injury) evaluations, and a postural control assessment at follow-up. Participants were grouped into those who exercised in between the time of injury and the follow-up evaluation and those who did not. Decisions regarding post-concussion exercise were made by a sports medicine team consisting of a single team physician and athletic trainers. RESULTS: Thirteen athletes were not included in the current study, resulting in an 85% response rate. Thirteen of the athletes who completed the study exercised between evaluations (18%). There was no symptom resolution time difference between groups (median = 13 [IQR = 7-18] days vs. 13 [7-23] days; p = 0.83). Symptom ratings were similar between groups at the acute post-injury assessment (median PCSS = 18.5 [7.5-26] vs. 17 [14-40]; p = 0.21), but a main effect of group after adjusting for time from injury to assessment indicated the exercise group reported lower symptom severity than the no exercise group across both assessments (p = 0.044). The dual-task gait speed of the exercise group was higher than the no exercise group (0.90 ±â€¯0.15 vs. 0.78 ±â€¯0.16 m/s; p = 0.02). CONCLUSIONS: Athletes who were recommended aerobic exercise after concussion did not have worse outcomes than those who were not. Exercise within the first week after concussion does not appear to be associated with detrimental clinical outcomes.

Tandem Gait Test-Retest Reliability Among Healthy Child and Adolescent Athletes.

CONTEXT: The tandem gait test is a method for assessing dynamic postural control and part of the Sport Concussion Assessment Tool, versions 3 and 5. However, its reliability among child and adolescent athletes has yet to be established. OBJECTIVE: To examine the test-retest reliability of the single-task and dual-task tandem gait test among healthy child and adolescent athletes. DESIGN: Descriptive laboratory study. SETTING: Sports injury-prevention center. PATIENTS OR OTHER PARTICIPANTS: Uninjured and healthy athletes between the ages of 9 and 18 years. INTERVENTION(S): Tandem gait measures repeated 3 times across the period of approximately 1 month. MAIN OUTCOME MEASURE(S): Participants completed the tandem gait test under single-task and dual-task (ie, while simultaneously executing a cognitive task) conditions. Our primary outcome measure was completion time during the single-task and dual-task conditions. We also assessed cognitive accuracy and response rate while participants completed the dual-task tandem gait test. RESULTS: Thirty-two child and adolescent athletes completed the study (mean age = 14.3 ± 2.4 years; females = 16). Single-task tandem gait times were similar across the 3 testing sessions (14.4 ± 4.8, 13.5 ± 4.2, and 13.8 ± 4.8 seconds; P = .45). Dual-task tandem gait times steadily improved across the test timeline (18.6 ± 6.9, 16.6 ± 4.5, and 15.8 ± 4.7 seconds; P = .02). Bivariate correlations indicated moderately high to high agreement from test 1 to test 2 (single-task r = .627; dual-task r = 0.655) and from test 2 to test 3 (single-task r = 0.852; dual-task r = 0.775). Both the single-task (intraclass correlation coefficient; ICC [3,1] = 0.86; 95% confidence interval [CI] = 0.73, 0.93) and dual-task (ICC [3,1] = 0.84; 95% CI = 0.69, 0.92) conditions demonstrated high reliability across testing sessions. CONCLUSIONS: Tandem gait outcome measures demonstrated high test-retest reliability in both the single- and dual-task conditions. The overall reliability was within the acceptable range for clinical practice, but improvements across tests suggested a moderate practice effect. Tandem gait represents a reliable, dynamic, postural-control test that requires minimal space, cost, and time.

Effect of Sports and Growth on Hamstrings and Quadriceps Development in Young Female Athletes: Cross-Sectional Study.

CONTEXT: Lower extremity muscular strength may vary by different sport participation during growth process. OBJECTIVE: To investigate effect of sport participation and growth by comparing strength of the hamstrings, quadriceps, and hamstrings to quadriceps strength ratio (H:Q ratio) between young female figure skaters and soccer players. DESIGN: Cross-sectional. SETTINGS: Laboratory affiliated with regional sports medicine center. PARTICIPANTS: pediatric and adolescent female athletes. PROCEDURES: Isometric hamstrings and quadriceps strength were measured. MAIN OUTCOME MEASURES: Strength of the hamstrings, quadriceps, and hamstrings to quadriceps strength ratio (H:Q ratio). STATISTICAL ANALYSIS: Effect of sport participation and growth was analyzed through a two-way (two sports: figure skaters and soccer players; three age groups: <12 years, 13-16 years, and >17 years) analysis of covariance. RESULTS: Hamstrings strength was significantly greater in figure skaters than soccer players. Also, hamstring strength of 13-16 years and >17 years was higher compared to <12 years. Additionally, significantly higher H:Q ratio in figure skaters compared to soccer players. CONCLUSIONS: There is effect of growth on hamstrings strength among 13-16 years and >17 years compared to <12 years. Figure skaters showed greater hamstrings strength and H:Q ratio than female soccer players.

Trouble Falling Asleep After Concussion Is Associated With Higher Symptom Burden Among Children and Adolescents.

Our objective was to identify factors associated with trouble falling asleep postconcussion. Patients seen for care after sport-related concussion were assessed ≤10 days postinjury and were between 6 and 19 years of age. Outcomes included symptoms (Post-Concussion Symptom Scale), postural steadiness, missed school, and medical history. There were 261 patients (49% female; mean age=14.8±2.5 years): 45% reported trouble falling asleep. A greater proportion of patients who reported trouble falling asleep missed ≥2 days of school (64% vs 49%; P = .02). Patients who reported trouble falling asleep endorsed more severe symptom severity than those who did not (median=38 vs 18; P < .001). After covariate adjustment, confusion (aOR = 1.95, 95% CI = 1.131-3.375), missing ≥2 days of school (aOR = 4.52, 95% CI = 1.553-13.16), and noise sensitivity (aOR = 1.48, 95% CI = 1.1.042-2.010) were independently associated with trouble falling asleep. Sleep disturbances are associated with poorer clinical outcomes after concussion. Inclusion of sleep assessments may help to provide early therapeutic pathways for pediatric concussion patients.

Objective clinical tests of dual-task dynamic postural control in youth athletes with concussion.

OBJECTIVES: To prospectively evaluate single/dual-task timed-up-and-go (TUG) and tandem gait performance among children and adolescents with concussion and healthy controls. DESIGN: Repeated measures. METHODS: Participants with concussion (n=23; age=14.1±2.5years; 52% female) completed single/dual-task TUG, tandem gait, and symptom assessments 6.7±2.6 and 23.3±6.1days post injury. The control group (n=27; age=14.1±2.3years; 48% female) completed the same protocol initially and 10.7±16.1days later. All participants completed single-task (undivided attention) and dual-task (divided attention) tests. The primary outcome variable was test completion time. RESULTS: The concussion group completed single-task (concussion group mean=11.1±1.9 vs. control group mean 9.9±1.4s, p=0.027) and dual-task (concussion group mean=14.4±3.3 vs. control group mean 12.7±1.9s, p=0.047) TUG tests slower than the control group across both time points. The concussion group completed dual-task tandem gait tests slower than the control group at both time points (21.3±6.3 vs. 16.8±5.5s, p=0.006), and were slower in the single-task condition at the first test (19.8±5.4 vs. 13.8±4.4s, p=0.003). Symptoms were significantly worse for the concussion group compared to the control group at the first (34.1±21.4 vs. 3.9±9.1, p<0.001), but not the second test (9.1±12.0 vs. 2.2±6.8; p=0.08). CONCLUSIONS: Slower dual-task TUG and tandem gait times were detected across both time points for the concussion group relative to the control group. In contrast, single-task tandem gait deficits appeared to improve in a similar fashion as symptoms, suggesting increased complexity from the addition of a cognitive task allows for the detection of persistent post-concussion deficits that might take longer to resolve.

Identifying Persistent Postconcussion Symptom Risk in a Pediatric Sports Medicine Clinic.

BACKGROUND: Although most children report symptom resolution within a month of a concussion, some patients experience persistent postconcussion symptoms (PPCS) that continues for more than 1 month. Identifying patients at risk for PPCS soon after an injury can provide useful clinical information. PURPOSE: To determine if the Predicting Persistent Post-concussive Problems in Pediatrics (5P) clinical risk score, an emergency department (ED)-derived and validated tool, is associated with developing PPCS when obtained in a primary care sports concussion setting. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We conducted a study of patients seen at a pediatric sports medicine concussion clinic between May 1, 2013, and October 1, 2017, who were <19 years of age and evaluated within 10 days of a concussion. The main outcome was PPCS, defined as symptoms lasting >28 days. Nine variables were used to calculate the 5P clinical risk score, and we assessed the association between the 5P clinical risk score and PPCS occurrence. The secondary outcome was total symptom duration. RESULTS: We examined data from 230 children (mean age, 14.8 ± 2.5 years; 50% female; mean time from injury to clinical assessment, 5.6 ± 2.7 days). In univariable analyses, a greater proportion of those who developed PPCS reported feeling slowed down (72% vs 44%, respectively; P < .001), headache (94% vs 72%, respectively; P < .001), sensitivity to noise (71% vs 43%, respectively; P < .001), and fatigue (82% vs 51%, respectively; P < .001) and committed ≥4 errors in tandem stance (33% vs 7%, respectively; P < .001) than those who did not. Higher 5P clinical risk scores were associated with increased odds of developing PPCS (adjusted odds ratio [OR], 1.62 [95% CI, 1.30-2.02]) and longer symptom resolution times (ß = 8.40 [95% CI, 3.25-13.50]). Among the individual participants who received a high 5P clinical risk score (9-12), the majority (82%) went on to experience PPCS. The area under the curve for the 5P clinical risk score was 0.75 (95% CI, 0.66-0.84). After adjusting for the effect of covariates, fatigue (adjusted OR, 2.93) and ≥4 errors in tandem stance (adjusted OR, 7.40) were independently associated with PPCS. CONCLUSION: Our findings extend the potential use for an ED-derived clinical risk score for predicting the PPCS risk into the sports concussion clinic setting. While not all 9 predictor variables of the 5P clinical risk score were independently associated with the PPCS risk in univariable or multivariable analyses, the combination of factors used to calculate the 5P clinical risk score was significantly associated with the odds of developing PPCS. Thus, obtaining clinically pragmatic risk scores soon after a concussion may be useful for early treatments or interventions to mitigate the PPCS risk.

Objective Eye Tracking Deficits Following Concussion for Youth Seen in a Sports Medicine Setting.

Quantification of visual deficits may help to identify dysfunction following concussion. We evaluated eye-tracking measurements among adolescents within 10 days of concussion and healthy control participants. Patients who reported to 2 tertiary care sport concussion clinics within 10 days of concussion completed an objective eye tracking assessment. Seventy-nine participants completed the study, 44 with concussion (mean age = 14.1 ± 2.2 years, 39% female) and 35 controls (mean age = 14.3 ± 2.4 years, 57% female). Right eye skew along the bottom of the screen was significantly higher for the concussion group compared to controls (median = 0.022 [interquartile range = -0.263, 0.482] vs 0.377 [interquartile range = -0.574, -0.031]; P = .002), but not the left eye. Among the variables investigated, right eye skew was altered for adolescents with a concussion. Visual function is an important component in the postconcussion evaluation, and identifying deficits soon after injury may allow for earlier specialist referral and intervention.

Running mechanics of females with bilateral compartment syndrome.

[Purpose] Primary purpose was to compare running mechanics between healthy runners and runners with chronic exertional compartment syndrome (CECS) including overstride angles, ankle dorsiflexion (DF) angles, and foot strike patterns. The secondary purpose was to analyze the association between the overstride angles and ankle DF angles. [Participants and Methods] Running images of 7 female runners with bilateral CECS patients were captured at a time of the medical examination. Their running images were compared with gender, age, and body mass index matched 31 healthy control runners. [Results] The bilateral CECS female runners have a propensity of running with significantly greater overstride and ankle DF angles than the healthy female runners. There were no foot strike differences between the two cohorts. There were a non-significant, poor relationship between overstride and ankle DF angles in the healthy female runners while a significant, strong association was found between overstride and ankle DF angles in the bilateral CECS female runners. [Conclusion] Compared to healthy female runners, bilateral CECS female runners demonstrated different running mechanics including greater overstride and ankle DF angles. The two variables were strongly associated with each other in bilateral CECS female runners, but not in healthy female runners. This may potentially contribute to the mechanism of CECS development.