Heading, an integral component of soccer, exposes athletes to a large number of head impacts over a career. The literature has begun to indicate that cumulative exposure may lead to long-term ...functional and psychological deficits. Quantifying an athlete's exposure over a season is a first step in understanding cumulative exposure.
To measure the frequency and magnitude of direct head impacts in collegiate women's soccer players across impact type, player position, and game or practice scenario.
Cross-sectional study.
National Collegiate Athletic Association Division I institution.
Twenty-three collegiate women's soccer athletes.
Athletes wore Smart Impact Monitor accelerometers during all games and practices. Impacts were classified during visual, on-field monitoring of athletic events. All direct head impacts that exceeded the 10 g threshold were included in the final data analysis. The dependent variable was linear acceleration, and the fixed effects were (1) type of impact: clear, pass, shot, unintentional deflection, or head-to-head contact; (2) field position: goalkeeper, defense, forward, or midfielder; (3) playing scenario: game or practice.
Shots (32.94 g ± 12.91 g, n = 38; P = .02) and clears (31.09 g ± 13.43 g, n = 101; P = .008) resulted in higher mean linear accelerations than passes (26.11 g ± 15.48 g, n = 451). Head-to-head impacts (51.26 g ± 36.61 g, n = 13; P < .001) and unintentional deflections (37.40 g ± 34.41 g, n = 24; P = .002) resulted in higher mean linear accelerations than purposeful headers (ie, shots, clears, and passes). No differences were seen in linear acceleration across player position or playing scenario.
Nonheader impacts, including head-to-head impacts and unintentional deflections, resulted in higher mean linear accelerations than purposeful headers, including shots, clears, and passes, but occurred infrequently on the field. Therefore, these unanticipated impacts may not add substantially to an athlete's cumulative exposure, which is a function of both frequency and magnitude of impact.
An emerging area of research has identified that an increased risk of musculoskeletal injury may exist upon returning to sports after a sport-related concussion. The mechanisms underlying this ...recently discovered phenomenon, however, remain unknown. One theorized reason for this increased injury risk includes residual neuromuscular control deficits that remain impaired despite clinical recovery. Thus, the objectives of this review were: (1) to summarize the literature examining the relationship between concussion and risk of subsequent injury and (2) to summarize the literature for one mechanism with a theorized association with this increased injury risk, i.e., neuromuscular control deficits observed during gait after concussion under dual-task conditions. Two separate reviews were conducted consistent with both specified objectives. Studies published before 9 December, 2016 were identified using PubMed, Web of Science, and Academic Search Premier (EBSCOhost). Inclusion for the objective 1 search included dependent variables of quantitative measurements of musculoskeletal injury after concussion. Inclusion criteria for the objective 2 search included dependent variables pertaining to gait, dynamic balance control, and dual-task function. A total of 32 studies were included in the two reviews (objective 1 n = 10, objective 2 n = 22). According to a variety of study designs, athletes appear to have an increased risk of sustaining a musculoskeletal injury following a concussion. Furthermore, dual-task neuromuscular control deficits may continue to exist after patients report resolution of concussion symptoms, or perform normally on other clinical concussion tests. Therefore, musculoskeletal injury risk appears to increase following a concussion and persistent motor system and attentional deficits also seem to exist after a concussion. While not yet experimentally tested, these motor system and attentional deficits may contribute to the risk of sustaining a musculoskeletal injury upon returning to full athletic participation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The National Collegiate Athletic Association (NCAA) has published concussion-management practice guidelines consistent with recent position and consensus statements. Whereas NCAA Division I athletic ...trainers appear highly compliant, little is known about the concussion-management practice patterns of athletic trainers at smaller institutions where staffing and resources may be limited.
To descriptively define the concussion-management practice patterns of NCAA Division II and III athletic trainers.
Cross-sectional study.
Web-based questionnaire.
A total of 755 respondents (response rate = 40.2%) from NCAA Division II and Division III institutions.
The primary outcome measures were the rate of multifaceted concussion-assessment techniques, defined as 3 or more assessments; the specific practice patterns of each assessment battery; and tests used during a clinical examination.
Most respondents indicated using a multifaceted assessment during acute assessment (Division II = 76.9%, n = 473; Division III = 76.0%, n = 467) and determination of recovery (Division II = 65.0%, n = 194; Division III = 63.1%, n = 288) but not at baseline (Division II = 43.1%, n = 122; Division III = 41.0%, n = 176). Typically, when a postconcussion assessment was initiated, testing occurred daily until baseline values were achieved, and most respondents (80.6% 244/278) reported using a graded exercise protocol before return to participation.
We found limited use of the multifaceted assessment battery at baseline but higher rates at both acute assessment and return-to-participation time points. A primary reason cited for not using test-battery components was a lack of staffing or funding for the assessments. We observed limited use of neuropsychologists to interpret neuropsychological testing. Otherwise, most respondents reported concussion-management protocols consistent with recommendations, including a high level of use of objective measures and incorporation of a progressive return-to-participation protocol.
There is increasing societal concern about the long-term effects of repeated impacts from soccer heading, but there is little information about ways to reduce head impact severity. The purpose of ...this study was to identify factors that contribute to head acceleration during soccer heading. One-hundred soccer players completed 12 controlled soccer headers. Peak linear (PLA) and rotational (PRA) accelerations were measured using a triaxial accelerometer and gyroscope. Head acceleration contributing factors were grouped into 3 categories: size (head mass, neck girth), strength (sternocleidomastoid, upper trapezius) and technique kinematics (trunk, head-to-trunk range-of-motion), sternocleidomastoid and upper trapezius activity. Multiple regression analyses indicated size variables explained 22.1% of the variance in PLA and 23.3% of the variance in PRA; strength variables explained 13.3% of the variance in PLA and 17.2% of the variance in PRA; technique variables did not significantly predict PLA or PRA. These findings suggest that head and neck size and neck strength predict PLA and PRA. Anthropometric and neck strength measurements should be considered when determining an athlete's readiness to begin soccer heading.
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BFBNIB, FSPLJ, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
PURPOSEThe purpose was to evaluate tandem gait (TG), Balance Error Scoring System (BESS), and modified Balance Error Scoring System (mBESS) performance acutely after concussion in collegiate ...student-athletes. In addition, we sought to evaluate the psychometric properties of TG, including minimal detectable change (MDC), sensitivity, and specificity.
METHODSSeventy-six National Collegiate Athletic Association student-athletes performed TG and BESS tests38 acutely after concussion and 38 controls. Participants were tested at baseline (time 1) and again acutely after concussion, or the following year for controls (time 2). Ten controls, tested simultaneously by two researchers, established a TG interrater minimal detectable change. A 2 × 2 mixed-design ANOVA compared each outcome variable. An receiver operating characteristic curve analysis was used to evaluate sensitivity, specificity, and area under the curve (AUC).
RESULTThere was a significant interaction (F = 8.757, P = 0.004) for TG whereby the concussion group was slower after concussion (10.59 ± 1.53 vs 11.80 ± 2.67 s), whereas there was no difference for controls (10.13 ± 1.72 vs 9.93 ± 1.85 s). There was no significant interaction for BESS (F = 0.235, P = 0.630) or mBESS (F = 0.007, P = 0.935). TG had a sensitivity of 0.632, a specificity of 0.605, and an AUC of 0.704. BESS had a sensitivity of 0.447, a specificity of 0.500, and an AUC of 0.508. mBESS had a sensitivity of 0.474, a specificity of 0.632, and an AUC of 0.535.
CONCLUSIONSParticipants completed TG significantly slower after concussion, whereas no change across time was detected for controls. In contrast, BESS and mBESS performances were similar at both testing times in both groups. Our AUC analysis was acceptable for TG, but a failure for both BESS and mBESS; thus, TG may be a useful alternative for clinicians conducting postconcussion postural control assessments.
Background The approach to the diagnosis of severe combined immunodeficiency disease (SCID) and related disorders varies among institutions and countries. Objectives The Primary Immune Deficiency ...Treatment Consortium attempted to develop a uniform set of criteria for diagnosing SCID and related disorders and has evaluated the results as part of a retrospective study of SCID in North America. Methods Clinical records from 2000 through 2009 at 27 centers in North America were collected on 332 children treated with hematopoietic stem cell transplantation (HCT), enzyme replacement therapy, or gene therapy for SCID and related disorders. Eligibility for inclusion in the study and classification into disease groups were established by using set criteria and applied by an expert review group. Results Two hundred eighty-five (86%) of the patients were determined to be eligible, and 47 (14%) were not eligible. Of the 285 eligible patients, 84% were classified as having typical SCID; 13% were classified as having leaky SCID, Omenn syndrome, or reticular dysgenesis; and 3% had a history of enzyme replacement or gene therapy. Detection of a genotype predicting an SCID phenotype was accepted for eligibility. Reasons for noneligibility were failure to demonstrate either impaired lymphocyte proliferation or maternal T-cell engraftment. Overall (n = 332) rates of testing were as follows: proliferation to PHA, 77%; maternal engraftment, 35%; and genotype, 79% (mutation identified in 62%). Conclusion Lack of complete laboratory evaluation of patients before HCT presents a significant barrier to definitive diagnosis of SCID and related disorders and prevented inclusion of subjects in our observational HCT study. This lesson is critical for patient care, as well as the design of future prospective treatment studies for such children because a well-defined and consistent study population is important for precision in outcomes analysis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Insulin and its receptor are known to be present and functional in the brain. Insulin cerebrospinal fluid concentrations have been shown to correlate with plasma levels of insulin in a nonlinear ...fashion, indicative of a saturable transport pathway from the blood to the brain interstitial fluid. The aim of the present study was to investigate whether insulin was transported across brain endothelial cells in vitro via an insulin receptor-dependent pathway. The study showed that the insulin receptor was expressed at both the mRNA and protein levels in bovine brain endothelial cells. Luminally applied radiolabeled insulin showed insulin receptor-mediated binding to the endothelial cells. This caused a dose-dependent increase in Akt-phosphorylation, which was inhibited by coapplication of an insulin receptor inhibitor, s961, demonstrating activation of insulin receptor signaling pathways. Transport of insulin across the blood-brain barrier in vitro was low and comparable to that of a similarly sized paracellular marker. Furthermore, insulin transport was not inhibited by coapplication of an excess of unlabeled insulin or an insulin receptor inhibitor. The insulin transport and uptake studies were repeated in mouse brain endothelial cells demonstrating similar results. Although it cannot be ruled out that culture-induced changes in the cell model could have impaired a potential insulin transport mechanism, these in vitro data indicate that peripheral insulin must reach the brain parenchyma through alternative pathways rather than crossing the blood-brain barrier via receptor mediated transcytosis.
OBJECTIVE:The purpose of this study was to explore the current reported, unreported, and potentially unrecognized concussion rates among collegiate student-athletes who have completed their ...collegiate athletic career.
DESIGN:Retrospective survey.
SETTING:College and University athletic training rooms.
PARTICIPANTS:One hundred sixty-one collegiate student-athletes (56.5% women; aged 21.5 ± 1.3; 3.7 ± 1.0 years of collegiate athletic experience) from 10 institutions who had either completed their intercollegiate athletic eligibility or were no longer participating.
MAIN OUTCOME MEASURES:The self-reported concussion rate, the unreported rate and reasons, and the potentially unrecognized concussion rate.
RESULTS:The self-reported concussion rate was 33.5% (54/161), and 22.2% (12) self-reported at least 3 concussions. The unreported rate was 11.8% (19/161), and the potentially unrecognized rate was 26.1% (42/161) with the most common unrecognized symptom being “knocked silly/seen stars” (23.6% 38/161).
CONCLUSIONS:Overall, 49.7% of all respondents (80/161) reported 1 acknowledged, unreported, or potential concussion. The unreported rate was lower than previous high school studies; however, the potentially unrecognized rate remains high and should be clinically concerning. These findings suggest educational interventions targeting collegiate student-athletes should remain and continue to focus on identifying concussion symptoms and dispelling the common misconception that “bell ringers” and “dings” are not concussions.
PURPOSEThe purpose of this study was to determine the relationship between repetitive head impacts (RHI) and clinical concussion assessments across a season among collegiate football (FB) and women’s ...soccer (WSOC) players.
METHODSFifteen male FB and 23 WSOC players participated in this study. Participants were included if they were medically cleared for unrestricted athletic participation. Participants were tested in a university athletic training room on two occasionspreseason (PRE) and postseason (POST). The outcome measures consisted of tandem gait (TG), Standardized Assessment of Concussion, Balance Error Scoring System, King-Devick (KD), clinical reaction time, and Immediate Post-Concussion Assessment and Cognitive Testing. Repetitive head impact during the season was quantified using the Head Impact Telemetry System (Simbex, NH) for FB and the Smart Impact Monitor (SIM; Triax Technologies, Norwalk, CT) for WSOC. Independent variables included total number of impacts, average magnitude of peak linear acceleration, cumulative linear exposure, and number of impacts ≥98g.
RESULTSResults from direct-entry multiple regression analyses suggest significant associations between RHI and both visual memory (R = 0.670, F = 6.487, P = 0.002) and TG (R = 0.636, F = 3.841, P = 0.029) for WSOC and between RHI and KD (R = 0.756, F = 5.579, P = 0.013) for FB, whereby those with greater exposure performed worse. No other regression analyses within or across groups were significant.
CONCLUSIONSThese data suggest that RHI do not represent clinically meaningful changes on a multifaceted and multimodal concussion assessment battery. However, there may be subtle visual/vestibular impairments as observed by the associations between RHI and visual memory/TG among WSOC, RHI, and KD among FB.
To determine the relationship between prolonged exposure to repetitive head impacts (RHI) through contact sports, as assessed by cumulative years contact sport participation, and quality of life ...outcomes in current/former contact sport athletes.
Cumulative lifetime RHI exposure may be a more meaningful measure than age of first exposure to contact sports to assess effects of RHI on neurologic function, however effects on young adults remain mixed.
Twenty-one physically active current/former contact sport athletes (35.0 ± 12.2 years, 66.7% male) completed an online questionnaire. To assess quality of life and psychological status, participants completed the Apathy Evaluation Scale-Self Rated (AES-S), Short Form 12 (SF-12), Satisfaction with Life Survey (SWLS), and Sport Concussion Assessment Tool 5 (SCAT5) Symptoms. Participants self-reported years of organized contact sport history (16.9 ± 10.5 years, range: 1-45) along with covariates (sex, LD/ADHD, age, concussion history). Generalized linear models were used to examine the association between cumulative years contact sport and psychological outcomes, while controlling for covariates.
Cumulative years contact sports was a significant positive predictor of better apathy ratings (
= 0.038) and SWLS (
= 0.001). For every year increase, there was an associated 1.1% reduction in AES-S and 1.6% improvement in SWLS. Cumulative years was not a significant predictor of SF-12 Mental Component Summary (
= 0.113), SF-12 Physical Component Summary (
= 0.289), or symptoms (
= 0.237).
Cumulative years of contact sport history was associated with better patient reported outcomes in current/former contact/collision sport athletes. This provides insight into later life effects of prolonged RHI exposure on neuropsychological outcomes in a more diverse subject pool outside of retired football players. Long-term neurologic effects remain to be elucidated, however, in early adulthood collision sports have positive mental health outcomes.
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