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 (ß=-3.43; 95%CI = -6.50, -0.36; p = 0.029) and cognitive (ß = -2.29; 95%CI = -4.22, -0.36; p = 0.02), but not somatic (ß=-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.

The Diagnostic Utility of Cervical Spine Proprioception for Adolescent Concussion.

OBJECTIVE: Cervical spine proprioception may be impaired after concussion. Our objective was to determine the diagnostic utility of cervical spine proprioception for adolescent concussion. DESIGN: Cross-sectional. SETTING: Research laboratory. PARTICIPANTS: Adolescents ≤18 days of concussion and uninjured controls. INTERVENTIONS: N/A. MAIN OUTCOMES: Head repositioning accuracy (HRA) testing, a measure of cervical spine proprioception. The HRA test involved patients relocating their head back to a neutral starting position with eyes closed after maximal cervical spine flexion, extension, and right and left rotations. The overall HRA error score was the mean error (distance from the starting point to self-reported return to neutral) across 12 trials: 3 trials in each direction. We used t-tests to compare group means and logistic regression (outcome = group, predictor = HRA, covariates) to calculate odds ratios. We used a receiver operator characteristic curve to evaluate area under the curve (AUC) and calculate the optimal HRA cutpoint to distinguish concussion from controls. RESULTS: We enrolled and tested 46 participants with concussion (age = 15.8 ± 1.3 years, 59% female, mean = 11.3 ± 3.3 days postconcussion) and 83 uninjured controls (age = 16.1 ± 1.4 years, 88% female). The concussion group had significantly worse HRA than controls (4.3 ± 1.6 vs 2.9 ± 0.7 degrees, P < 0.001, Cohen d = 1.19). The univariable HRA model AUC was 0.81 (95% CI = 0.73, 0.90). After adjusting for age, sex, and concussion history, the multivariable model AUC improved to 0.85 (95% CI = 0.77, 0.92). The model correctly classified 80% of participants as concussion/control at a 3.5-degree cutpoint. CONCLUSIONS: Adolescents with concussion demonstrated worse cervical spine proprioception than uninjured controls. Head repositioning accuracy may offer diagnostic utility for subacute concussion.

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.

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 (ß = 0.27; 95% confidence interval [CI], 0.01-0.53; P = 0.04) and light sensitivity (ß = 0.506; 95% CI, 0.061-0.951; P = 0.02), but not dizziness (ß = 0.390; 95% CI, -0.047 to 0.827; P = 0.08) or blurry vision (ß = 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.

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.

More Physical Activity Is Correlated With Reduction in Kinesiophobia for Adolescents With Persistent Symptoms After Concussion.

CONTEXT: The relationship between physical activity (PA) and fear of pain with movement (ie, kinesiophobia) during concussion recovery is unknown. Kinesiophobia may limit PA, while PA after concussion may reduce kinesiophobia. Our purpose was to examine the correlation between PA and self-reported kinesiophobia during concussion recovery for adolescents with and without persistent symptoms. DESIGN: Prospective cohort study of children ages 10-18 years within 14 days of concussion. METHODS: Participants rated kinesiophobia using the Tampa Scale of Kinesiophobia (TSK) at initial (≤14 d postconcussion) and return to play (RTP) assessments, and wore activity monitors between assessments. Our primary outcome was TSK score change from initial to RTP assessments. We grouped participants based on whether they experienced persistent symptoms (symptoms ≥28 days) or not (symptoms <28 days) and calculated correlation coefficients (Pearson r for normally distributed and Spearman rho for nonnormally distributed variables) between PA variables and TSK change scores. RESULTS: Among the 41 participants enrolled, 44% developed persistent symptoms (n = 18; age = 14.5 [2.0] y; 50% female; symptom duration = 57.3 [6.2] d; RTP = 66.8 [6.4] d) and 56% did not (n = 23; age = 14.9 [1.8] y; 48% female; symptom duration = 15.2 [1.5] d; RTP = 21.7 [1.9] d). For the persistent symptoms group, greater TSK change scores (mean = -2.5 [5.7] point change) were significantly and moderately correlated with higher daily step count (r = -.60, P = .008) and exercise frequency (r = -.63, P = .005), but were not correlated with exercise duration (ρ = -.12, P = .65). Among the no persistent symptoms group, TSK change scores (mean = -6.0 [5.0] point change) were not correlated with step count (r = -.18, P = .41) or exercise duration (ρ = .10, P = .67), and the correlation with frequency was low and not significant (r = -.34, P = .12). CONCLUSIONS: Regular PA during concussion recovery, regardless of duration or intensity, may help reduce kinesiophobia for those experiencing persistent symptoms.

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.

Dizziness Is Associated With Neck/Shoulder Pain Following Pediatric Concussion.

OBJECTIVE: To examine the association between dizziness and neck/shoulder pain after concussion and if differences in postural stability and oculomotor function exist among patients reporting dizziness with or without concurrent neck/shoulder pain. DESIGN: Cross sectional. SETTING: Sports medicine clinic. PATIENTS: Pediatric patients ≤14 days post concussion. INTERVENTIONS: N/A. OUTCOME MEASURES: Patients completed the Health and Behavior Inventory (HBI) symptom rating and separately rated neck/shoulder pain (scale 0-3; 0 = no pain). We grouped patients by HBI dizziness rating (0 = not-dizzy; 1-3 = dizzy) and compared neck/shoulder pain ratings between the groups. We then compared oculomotor and postural stability outcomes between dizzy patients with and without neck/shoulder pain. RESULTS: We included 153 patients: dizzy (n = 100; age = 14.6 ± 2.2 years; 48% female) and not-dizzy (n = 53, age = 14.4 ± 3.1 years; 38% female). The dizzy group reported significantly higher neck/shoulder pain (1.4 ± 1.1 vs 0.5 ± 0.9 points, P < 0.001) and total symptom score (25.7 ± 11.2 vs 11.7 ± 9.3 points, P < 0.001) than the not-dizzy group. After adjusting for total symptom score and preinjury anxiety, depression, and migraines, dizziness was associated with higher odds of neck/shoulder pain (odds ratio = 1.9, 95% CI, 1.2-3.0; P = 0.004). No differences were observed between dizzy patients with and without neck/shoulder pain for near point of convergence (10.0 ± 7.5 vs 8.5 ± 6.7 cm, P = 0.43), modified Balance Error Scoring System (8.9 ± 5.5 vs 6.8 ± 4.7 errors, P = 0.09), or tandem gait (single-task: 26.0 ± 12.3 vs 24.2 ± 11.9 seconds, P = 0.56; dual-task: 35.1 ± 14.3 vs 35.6 ± 18.6 seconds, P = 0.90). CONCLUSIONS: In concussion patients experiencing dizziness, evaluating neck/shoulder pain may help identify individuals who would benefit from cervical spine rehabilitation. However, other potential causes of dizziness should also be evaluated to facilitate timely recovery.

Sleep Problems and Melatonin Prescription After Concussion Among Youth Athletes.

OBJECTIVES: To examine the effect of sleep disturbances on concussion symptom recovery and to examine the effect of melatonin prescription on symptom improvement among concussed adolescents with sleep problems. DESIGN: Longitudinal test-retest. SETTING: Sports medicine clinic. PARTICIPANTS: Patients aged 8 to 18 years, diagnosed with a concussion, evaluated within 14 days after injury, and evaluated again 15 to 35 days after injury. INDEPENDENT VARIABLES: We grouped patients based on whether they reported sleep disturbances within 14 days of injury. MAIN OUTCOME MEASURES: Outcome measures included symptom severity, headache severity, melatonin prescription, and the change in symptom severity between visits. RESULTS: Two hundred twenty-five patients were included: 36% who reported sleep problems (44% female; age = 14.4 ± 2.0 years; evaluated 7.3 ± 3.8 and 23.2 ± 5.4 days after injury) and 64% who did not (32% female; age = 14.6 ± 2.3 years; evaluated 7.2 ± 3.4 and 23.0 ± 5.3 days after injury). Those with sleep problems reported higher symptom severity than those without across the 2 visits (22.1 ± 14.3 vs 14.6 ± 12.5; P < 0.001). There was no significant difference in the change in symptom severity between visits among those who received [median = 9-point improvement; interquartile range (IQR) = 1-14] and did not (median = 9, IQR = 2-18) receive a melatonin prescription (P = 0.80). CONCLUSIONS: Sleep problems among pediatric patients within 2 weeks of concussion are associated with more severe symptoms. Melatonin prescription was not associated with faster symptom recovery.

Web-Based Exercise Program Increases Cervical Strength in Adolescent Athletes.

ABSTRACT: Wilson, JC, Levek, C, Daoud, AK, Brewer, M, Brooks, K, Sochanska, A, Randall, M, and Provance, AJ. Web-based exercise program increases cervical strength in adolescent athletes. J Strength Cond Res 35(4): 1149-1155, 2021-This cohort study aimed to evaluate the efficacy of a web-based 6-week cervical strengthening program on cervical strength in adolescent athletes. It was hypothesized that subjects completing the program would demonstrate significant increase in cervical muscle strength compared with baseline strength. Eighty-three high school soccer athlete subjects were recruited from 2 local nationally competitive soccer clubs. Teams were assigned to either control or intervention groups to minimize information crossover. Fifty subjects were recruited to the intervention group (29 male, 21 female; average age 15.1 years). Thirty-three subjects were recruited to the control group (21 male, 12 female; average age 15.1 years). Intervention group subjects completed a web-based progressive cervical strengthening program over 6 weeks. Cervical strength in flexion, extension, right and left lateral flexion (LLF) was measured in Newton (N) of force at 3 time points during the competitive season for both control and intervention groups. Intervention group subjects significantly increased cervical strength [mean difference (95% confidence interval)] in LLF [24.1 (15.9-32.4)], extension [27.9 (18.4-37.5)], right lateral flexion [18.8 (11.6-26.1)], and flexion [mean ratio: 1.2 (1.1-1.2)] at follow-up testing; whereas control subjects did not see significant changes in strength. A web-based progressive cervical strengthening program improves cervical muscular strength in a population of adolescent athletes over a period of 6 weeks. Such a program could be used by researchers in future studies evaluating the influence on concussion risk and by practitioners as a means of reducing sport-related head and neck injuries.

Reliability and Minimal Detectable Change for a Smartphone-Based Motor-Cognitive Assessment: Implications for Concussion Management.

Our purpose was to investigate the reliability and minimal detectable change characteristics of a smartphone-based assessment of single- and dual-task gait and cognitive performance. Uninjured adolescent athletes (n = 17; mean age = 16.6, SD = 1.3 y; 47% female) completed assessments initially and again 4 weeks later. The authors collected data via an automated smartphone-based application while participants completed a series of tasks under (1) single-task cognitive, (2) single-task gait, and (3) dual-task cognitive-gait conditions. The cognitive task was a series of continuous auditory Stroop cues. Average gait speed was consistent between testing sessions in single-task (0.98, SD = 0.21 vs 0.96, SD = 0.19 m/s; P = .60; r = .89) and dual-task (0.92, SD = 0.22 vs 0.89, SD = 0.22 m/s; P = .37; r = .88) conditions. Response accuracy was moderately consistent between assessments in single-task standing (82.3% accurate, SD = 17.9% vs 84.6% accurate, SD = 20.1%; P = .64; r = .52) and dual-task gait (89.4% accurate, SD = 15.9% vs 85.8% accurate, SD = 20.2%; P = .23; r = .81) conditions. Our results indicate automated motor-cognitive dual-task outcomes obtained within a smartphone-based assessment are consistent across a 1-month period. Further research is required to understand how this assessment performs in the setting of sport-related concussion. Given the relative reliability of values obtained, a smartphone-based evaluation may be considered for use to evaluate changes across time among adolescents, postconcussion.

The Nocebo Effect and Pediatric Concussion.

While placebo effects are well recognized within clinical medicine, "nocebo effects" have received much less attention. Nocebo effects are problems caused by negative expectations derived from information or treatment provided during a clinical interaction. In this review, we examine how nocebo effects may arise following pediatric concussion and how they may worsen symptoms or prolong recovery. We offer several suggestions to prevent, lessen, or eliminate such effects. We provide recommendations for clinicians in the following areas: terminology selection, explicit and implicit messaging to patients, evidence-based recommendations, and awareness of potential biases during clinical interactions. Clinicians should consider the empirically grounded suggestions when approaching the care of pediatric patients with concussion.

A Longitudinal Investigation of Symptom Recovery following Concussion in Youth Soccer.

OBJECTIVE: To prospectively evaluate symptom outcomes after youth soccer-related concussion. STUDY DESIGN: Using a prospective cohort design, we enrolled male and female competitive soccer players age 8-17 years into 3 groups: concussed (n = 23), matched control (n = 23), and orthopedic injury (n = 24). Postconcussive symptoms were monitored serially via both athlete and parent report at days 1-2, 4, 7, 10, 30, and 90. RESULTS: Repeated-measures analyses revealed a significant time by group interaction (F [12, 402] = 19.91, P < .001). In the initial days postinjury, the concussed group reported greater symptoms than the comparison groups, with more symptoms reported by athletes on average than parents. By 10 days, concussed athletes did not differ from the matched controls by either rater's report, but they did differ from the orthopedic injury group by parent report. At 30 days, no differences were apparent among groups. At 30 days, 100% of concussed youth and 91% of parents rated symptoms as back to preinjury levels using reliable change indices. At 30 days, 86% of athletes had been cleared to return to full game play. CONCLUSIONS: The natural clinical history of concussion symptoms in youth competitive soccer players was similar to that seen in older athletes, with resolution in days to a few weeks. Additional study will be required to investigate which factors best predict symptom outcomes for individual athletes and how symptom report relates to performance-based outcome measures and underlying neurophysiologic recovery.

Symptom profiles and postural control after concussion in female artistic athletes.

OBJECTIVES: The purpose of our investigation was to compare post-concussion symptom profiles and postural control measures among female youth artistic athletes (gymnasts and cheerleaders) relative to female ball sport athletes (volleyball or basketball). METHODS/FINDINGS: We compared 27 artistic athletes (median age = 15.0 years; evaluated median = 13 days post-injury) and 49 ball sport athletes (median age = 15.3 years; evaluated median = 10 days post-injury) within 21 days of sustaining a concussion on measures of symptom profiles and postural control (Balance Error Scoring System [BESS]), tandem gait, and Romberg tests. After adjusting for the independent effect of time from injury-evaluation, concussion history, and pre-morbid migraine history, we observed that artistic athletes performed the BESS tandem stance foam condition with fewer errors than ball sport athletes (ß = -2.4; 95% CI = -4.7, -0.2; p = .03). Artistic athletes demonstrated a higher, yet not statistically significant, headache severity than ball sport athletes (median = 4.5 vs 4.0, p = .07). CONCLUSIONS: Overall, artistic athletes had similar symptom profiles to ball sport athletes. Postural control measures, other than the BESS tandem stance foam condition, were not significantly different from ball sport athletes. This suggests that although their sports may require higher levels of balance, artistic athletes' performance on post-concussion balance tests may be similar to athletes of other disciplines.

Dual-Task Gait Stability after Concussion and Subsequent Injury: An Exploratory Investigation.

Persistent gait alterations can occur after concussion and may underlie future musculoskeletal injury risk. We compared dual-task gait stability measures among adolescents who did/did not sustain a subsequent injury post-concussion, and uninjured controls. Forty-seven athletes completed a dual-task gait evaluation. One year later, they reported sport-related injuries and sport participation volumes. There were three groups: concussion participants who sustained a sport-related injury (n = 8; age =15.4 ± 3.5 years; 63% female), concussion participants who did not sustain a sport-related injury (n = 24; 14.0 ± 2.6 years; 46% female), and controls (n = 15; 14.2 ± 1.9 years; 53% female). Using cross-recurrence quantification, we quantified dual-task gait stability using diagonal line length, trapping time, percent determinism, and laminarity. The three groups reported similar levels of sports participation (11.8 ± 5.8 vs. 8.6 ± 4.4 vs. 10.9 ± 4.3 hours/week; p = 0.37). The concussion/subsequent injury group walked slower (0.76 ± 0.14 vs. 0.65 ± 0.13 m/s; p = 0.008) and demonstrated higher diagonal line length (0.67 ± 0.08 vs. 0.58 ± 0.05; p = 0.02) and trapping time (5.3 ± 1.5 vs. 3.8 ± 0.6; p = 0.006) than uninjured controls. Dual-task diagonal line length (hazard ratio =1.95, 95% CI = 1.05-3.60), trapping time (hazard ratio = 1.66, 95% CI = 1.09-2.52), and walking speed (hazard ratio = 0.01, 95% CI = 0.00-0.51) were associated with subsequent injury. Dual-task gait stability measures can identify altered movement that persists despite clinical concussion recovery and is associated with future injury risk.

American Medical Society for Sports Medicine position statement on concussion in sport.

Sport-related concussion (SRC) is a common injury in recreational and organised sport. Over the past 30 years, there has been significant progress in our scientific understanding of SRC, which in turn has driven the development of clinical guidelines for diagnosis, assessment and management of SRC. In addition to a growing need for knowledgeable healthcare professionals to provide evidence-based care for athletes with SRC, media attention and legislation have created awareness and, in some cases, fear about many issues and unknowns surrounding SRC. The American Medical Society for Sports Medicine (AMSSM) formed a writing group to review the existing literature on SRC, update its previous position statement, and to address current evidence and knowledge gaps regarding SRC. The absence of definitive outcomes-based data is challenging and requires relying on the best available evidence integrated with clinical experience and patient values. This statement reviews the definition, pathophysiology and epidemiology of SRC, the diagnosis and management of both acute and persistent concussion symptoms, the short-term and long-term risks of SRC and repetitive head impact exposure, SRC prevention strategies, and potential future directions for SRC research. The AMSSM is committed to best clinical practices, evidence-based research and educational initiatives that positively impact the health and safety of athletes.

American Medical Society for Sports Medicine Position Statement on Concussion in Sport.

Sport-related concussion (SRC) is a common injury in recreational and organized sport. Over the past 30 years, there has been significant progress in our scientific understanding of SRC, which in turn has driven the development of clinical guidelines for diagnosis, assessment, and management of SRC. In addition to a growing need for knowledgeable health care professionals to provide evidence-based care for athletes with SRC, media attention and legislation have created awareness and, in some cases, fear about many issues and unknowns surrounding SRC. The American Medical Society for Sports Medicine formed a writing group to review the existing literature on SRC, update its previous position statement, and address current evidence and knowledge gaps regarding SRC. The absence of definitive outcomes-based data is challenging and requires relying on the best available evidence integrated with clinical experience and patient values. This statement reviews the definition, pathophysiology, and epidemiology of SRC, the diagnosis and management of both acute and persistent concussion symptoms, the short- and long-term risks of SRC and repetitive head impact exposure, SRC prevention strategies, and potential future directions for SRC research. The American Medical Society for Sports Medicine is committed to best clinical practices, evidence-based research, and educational initiatives that positively impact the health and safety of athletes.

Athletes Doing Arabesques: Important Considerations in the Care of Young Dancers.

Dance is as much a sport as an art form. Sports medicine clinicians seeing dancers in their practice will need to be familiar with the unique characteristics of dance in order to provide proper care. Dance encompasses different forms, which vary in equipment and terminology. The epidemiology of dance injuries has historically focused on ballet, but there is increasing research on other dance forms. Lower extremity and back injuries predominate. Injury prevention, both primary and secondary, is at the heart of dance medicine. Primary prevention includes preseason conditioning, identifying risk factors for injury, and recognizing the female athlete triad. Secondary prevention includes a comprehensive approach to injury rehabilitation, an appreciation for the unique demands of dance, and an understanding of the particulars of the injury being treated. Dancers may have difficulty accessing medical care or following prescribed advice; the proactive clinician will anticipate these situations.

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 (ß = 58.8; 95% CI = 29.2, 88.3; P < .001) and dual-task Stroop (ß = 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.

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.