Search

Disruptions in gait function are common after concussion in adolescents; however, the neuromotor control deficits driving these gait disruptions are not well known. Fifteen concussed (age mean [SD]): 17.4 [0.6], 13 females, days since injury: 26.3 [9.9]) and 17 uninjured (age: 18.0 [0.7], 10 females) adolescents completed 3 trials each of single-task gait and dual-task gait (DT). During DT, participants simultaneously walked while completing a serial subtraction task. Gait metrics and variability in instantaneous mean frequency in lower extremity muscles were captured by inertial sensors and surface electromyography, respectively. A 2-way analysis of covariance was used to compare gait metrics across groups and conditions. Functional principal components analysis was used to identify regions of variability in instantaneous mean frequency curves. Functional principal component scores were compared across groups using a Welch statistic. Both groups displayed worse performance on gait metrics during DT condition compared to single-task, with no differences between groups (P <.001). Concussed adolescents displayed significantly greater instantaneous mean frequency, indicated by functional principal component 1, in the tibialis anterior, biceps femoris, and semitendinosus (P <.05) during single-task and DT compared with uninjured adolescents. Our observations suggest that concussed adolescents display inefficient motor unit recruitment lasting longer than 2 weeks following injury, regardless of the addition of a secondary task. [ABSTRACT FROM AUTHOR]

Concussion research has primarily focused on sport-related mechanisms and excluded non–sport-related mechanisms. In adult populations, non–sport-related concussions (non-SRCs) demonstrated worse clinical outcomes compared with sport-related concussions (SRCs); however, investigations of non-SRCs in college-aged patients are limited. To examine clinical outcomes in collegiate athletes with non-SRCs compared with SRCs and explore sex differences in outcomes among collegiate athletes with non-SRCs. Prospective cohort study. Clinical setting. A total of 3500 athletes were included (n = 555 with non-SRCs, 42.5% female) from colleges or universities and service academies participating in the National Collegiate Athletic Association Department of Defense Concussion Assessment, Research and Education (CARE) Consortium. Dichotomous outcomes (yes or no) consisted of immediate reporting, mental status alterations, loss of consciousness, posttraumatic amnesia, retrograde amnesia, motor impairments, delayed symptom presentation, and required hospital transport. Continuous outcomes were symptom severity, days with concussion symptoms, and days lost to injury. Data were collected within 24 to 48 hours of injury and at return to play. Adjusted relative risks (ARRs) compared the likelihood of dichotomous outcomes by mechanism and by sex within patients with non-SRCs. Multivariate negative binomial regressions were used to assess group differences in continuous variables. Athletes with non-SRCs were less likely to report immediately (ARR = 0.73, 95% CI = 0.65, 0.81) and more likely to report delayed symptom presentation (ARR = 1.17, 95% CI = 1.03, 1.32), loss of consciousness (ARR = 3.15, 95% CI = 2.32, 4.28), retrograde amnesia (ARR = 1.77, 95% CI = 1.22, 2.57), and motor impairment (ARR = 1.45, 95% CI = 1.14, 1.84). Athletes with non-SRCs described greater symptom severity, more symptomatic days, and more days lost to injury (P <.001) compared with those who had SRCs. Within the non-SRC group, female athletes indicated greater symptom severity, more symptomatic days, and more days lost to injury (P <.03) than male athletes. Athletes with non-SRCs had worse postinjury outcomes compared with those who had SRCs, and female athletes with non-SRCs had worse recovery metrics than male athletes. Our findings suggest that further investigation of individuals with non-SRCs is needed to improve concussion reporting and management. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Growing evidence indicates early exercise may improve symptoms and reduce clinical recovery time after concussion, but research examining collegiate student-athletes is scarce. Objective: The aim of this study was to compare symptom recovery time, clinical recovery time, and persisting post-concussion symptom (i.e., symptoms ≥ 28 days) prevalence by the timing of light exercise initiation before the graded return to play (RTP) protocol among concussed participants. Methods: Collegiate student-athletes (n = 1228; age 18.4 ± 0.9 years; 56.5% male, 76.3% division I; 33.7% ≥ 1 prior concussion) across 30 institutions enrolled in the CARE Consortium completed post-concussion assessments and were monitored over time. Symptom recovery (days from injury to symptom resolution) and clinical recovery (days from injury to return to play protocol completion) was determined by the student-athletes' clinicians. Student-athletes were categorized by timing of light exercise initiation. Early (< 2 days post-concussion; n = 161), typical (3–7 days post-concussion; n = 281), and late exercise (≥ 8 days post-concussion; n = 169) groups were compared with the no-exercise group (n = 617; i.e., did not exercise prior to beginning the RTP protocol) for all analyses. Multivariable Cox regression models with hazard ratios (HR) and survival curves and a multivariable binomial regression model with prevalence ratios (PR) compared recovery outcomes between exercise groups while accounting for covariates. Results: Compared to the no-exercise group, the early exercise group was 92% more probable to experience symptom recovery (HR 1.92; 95% CI 1.57–2.36), 88% more probable to reach clinical recovery (HR 1.88; 95% CI 1.55–2.28) and took a median of 2.4 and 3.2 days less to recover, respectively. The late exercise group relative to the no-exercise group was 57% less probable to reach symptom recovery (HR 0.43; 95% CI 0.35–0.53), 46% less probable to achieve clinical recovery (HR 0.54; 95% CI 0.45–0.66) and took 5.3 days and 5.7 days more to recover, respectively. The typical exercise group did not differ in hazard for symptom or clinical recovery (p ≥ 0.329) compared with the no-exercise group. The prevalence of persisting post-concussion symptoms in the combined sample was 6.6%. Early exercise had 4% lower prevalence (PR 0.96, 95% CI 0.94–0.99) and typical exercise had 3% lower prevalence (PR 0.97, 95% CI 0.94–0.99) of persisting post-concussion symptoms, while the late exercise group had an elevated prevalence (PR 1.11, 95% CI 1.04–1.18) compared with the no-exercise group. Conclusion: Exercise < 2 days post-concussion was associated with more probable and faster symptom and clinical recovery, and lower persisting post-concussion symptom prevalence. When considering our findings and existing literature, qualified clinicians may implement early exercise into their clinical practice to provide therapeutic treatment and improve student-athlete recovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Affective symptoms, specifically, anxiety, are often overlooked after sport-related concussion (SRC), and may contribute to prolonged recovery. OBJECTIVE: To examine the impact of anxiety during clinical recovery among adolescents (13–18y) enrolled in a randomized trial of aerobic exercise for SRC. METHODS: Patients at three sites were randomized into aerobic exercise or stretching arms, and enrolled in the 4-week intervention. The relationship between PROMIS Anxiety score at initial visit and time to symptom resolution was evaluated with survival analysis. The relationship between weekly PROMIS Anxiety score and Post-concussion Symptom Inventory (PCSI) score was evaluated with Linear Mixed Models. Analyses adjusted for study arm and baseline covariates. RESULTS: Among 54 adolescents (median age = 15.8y, initial visit PCSI score = 32, pre-injury PROMIS Anxiety score = 2), median time to symptom resolution was 10 days (25th-75th percentiles: 6-24) in the Low-PROMIS Anxiety group and 12 days (25th-75th percentiles: 5-21) in the High-PROMIS Anxiety group (p = 0.62). Each additional unit of PROMIS Anxiety score corresponded to a 1.52-unit higher PCSI total score (p < 0.01). Neither effect varied by aerobic exercise/stretching group. CONCLUSION: Higher initial PROMIS Anxiety score was not significantly associated with delayed symptom resolution. However, over time, PROMIS Anxiety score was significantly associated with elevated PCSI score, regardless of exercise/stretching group. [ABSTRACT FROM AUTHOR]

Background: Recent advances in technology have enabled the development of head impact sensors, which provide a unique opportunity for sports medicine researchers to study head kinematics in contact sports. Studies have suggested that video or observer confirmation of head impact sensor data is required to remove false positives. In addition, manufacturer filtering algorithms may be ineffective in identifying true positives and removing true negatives. Purpose: To (1) identify the percentage of video-confirmed events recorded by headband-mounted sensors in high school soccer through video analysis, overall and by sex; (2) compare video-confirmed events with the classification by the manufacturer filtering algorithms; and (3) quantify and compare the kinematics of true- and false-positive events. Study Design: Cohort study; Level of evidence, 2. Methods: Adolescent female and male soccer teams were instrumented with headband-mounted impact sensors (SIM-G; Triax Technologies) during games over 2 seasons of suburban high school competition. Sensor data were sequentially reduced to remove events recorded outside of game times, associated with players not on the pitch (ie, field) and players outside the field of view of the camera. With video analysis, the remaining sensor-recorded events were identified as an impact event, trivial event, or nonevent. The mechanisms of impact events were identified. The classifications of sensor-recorded events by the SIM-G algorithm were analyzed. Results: A total of 6796 sensor events were recorded during scheduled varsity game times, of which 1893 (20%) were sensor-recorded events associated with players on the pitch in the field of view of the camera during verified game times. Most video-confirmed events were impact events (n = 1316, 70%), followed by trivial events (n = 396, 21%) and nonevents (n = 181, 10%). Female athletes had a significantly higher percentage of trivial events and nonevents with a significantly lower percentage of impact events. Most impact events were head-to-ball impacts (n = 1032, 78%), followed by player contact (n = 144, 11%) and falls (n = 129, 10%) with no significant differences between male and female teams. The SIM-G algorithm correctly identified 70%, 52%, and 66% of video-confirmed impact events, trivial events, and nonevents, respectively. Conclusion: Video confirmation is critical to the processing of head impact sensor data. Percentages of video-confirmed impact events, trivial events, and nonevents vary by sex in high school soccer. Current manufacturer filtering algorithms and magnitude thresholds are ineffective at correctly classifying sensor-recorded events and should be used with caution. [ABSTRACT FROM AUTHOR]

Primary care providers are increasingly providing youth concussion care but report insufficient time and training, limiting adoption of best practices. We implemented a primary care-based intervention including an electronic health record-based clinical decision support tool ("SmartSet") and in-person training. We evaluated consequent improvement in 2 key concussion management practices: (1) performance of a vestibular oculomotor examination and (2) discussion of return-to-learn/return-to-play (RTL/RTP) guidelines. Data were included from 7284 primary care patients aged 0 to 17 years with initial concussion visits between July 2010 and June 2014. We compared proportions of visits pre- and post-intervention in which the examination was performed or RTL/RTP guidelines provided. Examinations and RTL/RTP were documented for 1.8% and 19.0% of visits pre-intervention, respectively, compared with 71.1% and 72.9% post-intervention. A total of 95% of post-intervention examinations were documented within the SmartSet. An electronic clinical decision support tool, plus in-person training, may be key to changing primary care provider behavior around concussion care. [ABSTRACT FROM AUTHOR]

Objective: Investigate the reliability of concussion symptoms captured through ecological momentary assessment (EMA) and compare time with recovery based on 3 definitions of symptomatic recovery and the date of clinical clearance to begin the return-to-play (RTP) process. Design: We used a mobile app with EMA to monitor concussion symptoms as part of a multicenter randomized controlled trial. Setting: Three sports medicine practices. Participants: Patients between 13 and 18 years old with sport-related concussion were prompted to complete the Post-Concussion Symptom Inventory daily over 4 weeks. Interventions: None. Main Outcome Measures: We compared the elapsed days to reaching the 4 outcomes using scatterplots and Kaplan–Meier curves. Results: Among 118 participants, symptoms reported into the app had excellent agreement with symptoms reported at a clinical visit on the same day (intraclass correlation coefficient = 0.97). Most (>50%) participants reached "specific symptom return to preinjury levels," "overall symptom return to preinjury levels," and "current symptom resolution" based on EMA symptom reports between several days and 1 week before achieving "clinical clearance to RTP" determined at a clinical visit, which had 100% sensitivity, but between 56.3% and 78.1% specificity, relative to the app-measured symptom outcomes. Conclusions: Time until symptom recovery varies based on the chosen definition of symptomatic recovery but is a more precise correlate with clinical clearance to begin the RTP process when defining symptom recovery as a return to a preinjury baseline level of symptomatology. Real-time symptom monitoring may be beneficial clinically, allowing providers to assess patients' recovery status and make more timely and remote treatment recommendations. [ABSTRACT FROM AUTHOR]

This study sought to test the hypothesis that significant differences would be observed in clinical measures, symptoms, and objective assessments of vergence eye movements between children with typically developing convergence insufficiency (TYP-CI) and children with persistent post-concussion symptoms with convergence insufficiency (PPCS-CI). Data from age-matched binocularly normal controls (BNC) were used for comparison. Data from three groups of children 11 to 17 years of age are presented: BNC (N = 11), TYP-CI (N = 10), and PPCS-CI (N = 15). Clinical measures of vergence, accommodation, and symptom severity were collected. Symmetrical 4° disparity vergence eye movements were quantified with an eye tracker integrated into a head-mounted display (Oculus DK2). Peak velocity and final response amplitude of convergence and divergence eye movement responses were assessed. The mean near point of convergence (break) was more receded (worse), the amplitude of accommodation more deficient, and convergent and divergent peak velocities slower in the PPCS-CI group compared with the TYP-CI and BNC groups. These results suggest that PPCS-CI may be a different clinical entity than TYP-CI. Hence, more research is warranted to determine whether the therapeutic interventions that are effective for TYP-CI can also be used for PPCS-CI populations. [ABSTRACT FROM AUTHOR]

Purpose: Evaluate the discriminatory ability of two clinical measures and one device-based measure of gait and balance for concussed youth. Methods: We enrolled 81 cases and 90 controls age 14–18 yr old from August 2017 to June 2018. Controls were recruited from a suburban high school, and cases were recruited from the concussion program of an academic pediatric tertiary care center. Tests included two clinical measures: 1) complex tandem gait, scored as sway/errors walking forward and backward eyes open and closed; 2) Modified Balance Error Scoring System (mBESS), scored as total number of errors on three standing tasks; and one device-based measure; 3) Modified Clinical Test of Sensory Interaction and Balance (mCTSIB) using the Biodex Biosway Balance System, scored as a sway index. Sensitivity, specificity, ideal cutpoint, and area under the receiver operating characteristic curve (AUC) were calculated for all test components. Results: Ideal cutpoint for total number of sway/errors for tandem gait = 5, sensitivity 41%, specificity 90%. Ideal cutpoint for total mBESS errors = 4, sensitivity 55%, specificity 75%. Ideal cutpoint for mCTSIB = 1.37, sensitivity 37%, specificity 88%. Among each test, some individual components outperformed overall composites, in particular tandem gait (specificity forward eyes open = 99%, sensitivity backward eyes closed = 81%). Among the 40 cases and 65 controls with all three assessments, AUC (95% CI) for tandem gait = 0.63 (0.52,0.75), mBESS = 0.70 (0.60,0.81), and mCTSIB = 0.54 (0.42,0.66). Conclusions: A device-based measure of balance did not produce better discriminatory ability than two clinical assessments. Complex tandem gait has the additional benefit of being an easy-to-perform and graded test with highly sensitive and specific individual components. [ABSTRACT FROM AUTHOR]

Gait deficits are common after concussion in adolescents. However, the neurophysiological underpinnings of these gait deficiencies are currently unknown. Thus, the goal of this study was to compare spatiotemporal gait metrics, prefrontal cortical activation, and neural efficiency between concussed adolescents several weeks from injury and uninjured adolescents during a dual-task gait assessment. Fifteen concussed (mean age[SD]: 17.4[0.6], 13 female, days since injury: 26.3[9.9]) and 17 uninjured adolescents (18.0[0.7], 10 female) completed a gait assessment with three conditions repeated thrice: single-task walking, single-task subtraction, and dual-task, which involved walking while completing a subtraction task simultaneously. Gait metrics were measured using an inertial sensor system. Prefrontal cortical activation was captured via functional near-infrared spectroscopy. Neural efficiency was calculated by relating gait metrics to prefrontal cortical activity. Differences between groups and conditions were examined, with corrections for multiple comparisons. There were no significant differences in gait metrics between groups. Compared to uninjured adolescents, concussed adolescents displayed significantly greater prefrontal cortical activation during the single-task subtraction (P = 0.01) and dual-task (P = 0.01) conditions with lower neural efficiency based on cadence (P = 0.02), gait cycle duration (P = 0.03), step duration (P = 0.03), and gait speed (P = 0.04) during the dual-task condition. Our findings suggest that several weeks after injury concussed adolescents demonstrate lower neural efficiency and display a cost to gait performance when cognitive demand is high, e.g., while multitasking, suggesting that the concussed adolescent brain is less able to compensate when attention is divided between two concurrent tasks. • Instrumented dual-task gait protocol was employed in concussed adolescents. • Gait metrics, prefrontal cortical activation, and neural efficiency were assessed. • Concussed adolescents had lower neural efficiency during dual-task gait. [ABSTRACT FROM AUTHOR]