Dustin W. Currie

Altitude Modulates Concussion Incidence Implications for Optimizing Brain Compliance to Prevent Brain Injury in Athletes

Background: Recent research indicates that the volume and/or pressure of intracranial fluid, a physiology affected by one’s altitude (ie, elevation above sea level), may be associated with the likelihood and/or severity of a concussion. The objective was to employ an epidemiological field investigation to evaluate the relationship between altitude and concussion rate in high school sports. Hypothesis: Because of the physiologies that occur during acclimatization, including a decline in intracranial compliance (a “tighter fit”), increased altitude may be related to a reduction in concussion rates in high school athletes. Study Design: Cohort study; Level of evidence, 3. Methods: Data on concussions and athlete exposures (AEs) between 2005-2006 and 2011-2012 were obtained from a large national sample of high schools (National High School Sports-Related Injury Surveillance System [High School RIO]) and were used to calculate total, competition, and practice concussion rates for aggregated sports and for football only. Results: Altitude of participating schools ranged from 7 to 6903 ft (median, 600 ft), and a total of 5936 concussions occurred in 20,618,915 exposures (2.88 per 10,000 AEs). When concussion rates were dichotomized by altitude using the median, elevated altitude was associated with a reduction in concussion rates overall (rate ratio [RR], 1.31; P < .001), in competition (RR, 1.31; P < .001), and in practice (RR, 1.29; P < .001). Specifically, high school sports played at higher altitude demonstrated a 31% reduction (95% confidence interval [CI], 25%-38%) in the incidence of total reported concussions. Likewise, concussion rates at increased altitude were reduced 30% for overall exposures, 27% for competition exposures, and 28% for practice exposures in football players (P < .001). Conclusion: The results of this epidemiological investigation indicate increased physiological responses to altitude may be associated with a reduction in sports-related concussion rates, especially in collision sports. Future research that focuses on the potential prophylactic effect of optimizing outflow impedance and thus reduction of intracranial compliance (a “tighter fit”) in humans is warranted to determine the most effective approaches to mitigate sport-related concussion, especially in football players.

Epidemiology of Patellofemoral Instability Injuries Among High School Athletes in the United States

Background: Patellofemoral instability injuries, including dislocations and subluxations, are relatively rare in the general population but are believed to be much more common in young athletic patient populations, such as high school athletes. In spite of the relatively high risk, the epidemiology of such injuries in this population has not been clearly elucidated. Purpose: To provide a comprehensive understanding of the epidemiology of patellofemoral instability injuries among high school athletes in the United States. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Data were obtained from the National High School Sports-Related Injury Surveillance System, High School RIO (Reporting Information Online), an Internet-based sports injury surveillance system. Athletic trainers from high schools across the country uploaded data regarding athlete exposures (defined as practice or game participation) and injuries across 22 sports from 2007-2008 through 2012-2013. Data were collected regarding athlete demographics, injury mechanism and details, practice versus competition, return to sport, and the need for surgery. Results: A total of 421 patellar instability (143 dislocations and 278 subluxations) injuries occurred during 21,556,515 athlete exposures (AEs) during the study period, for an overall injury rate of 1.95 per 100,000 AEs. The highest injury rates were noted in girls’ gymnastics (6.19 per 100,000 AEs), boys’ football (4.10), and boys’ wrestling (3.45). The overall injury rate was significantly lower for girls than boys (1.66 and 2.15, respectively; rate ratio [RR], 0.77; 95% CI, 0.62-0.94). In contrast, among only the sex-comparable sports, the injury rate was higher for girls than boys (1.47 and 0.88, respectively; RR, 1.67; 95% CI, 1.19-2.34). The rate of injury was higher in competition (3.72) than practice (1.34) (RR, 2.78; 95% CI, 2.29-3.36). A no-contact injury mechanism was the most commonly reported mechanism (37.8% of injuries), followed by player-to-player contact (36.8%). When all contact subcategories are combined, the overall contact mechanism represents 59.3% of injuries. Return to play after a patellofemoral instability injury occurred within 3 weeks for 59.5% of athletes. Return to play in >3 weeks (16.0%) and loss of the remainder of the season (20.0%) were less common outcomes. Conclusion: Patellofemoral instability injury rates vary by sport, sex, and type of exposure (competition vs practice). A better understanding of such patterns of patellofemoral instability injury will help drive formulation of new injury prevention strategies and decrease the risk for patellofemoral instability injury among high school athletes.

Epidemiology of Elbow Dislocations in High School Athletes

Background: The elbow is the second most commonly dislocated major joint in the general population. Previous studies that focused on emergency department populations indicate that such injuries occur most frequently among adolescent athletes. Purpose: To describe the epidemiological rates and patterns of sports-related elbow dislocations in high school athletes. Study Design: Descriptive epidemiology study. Methods: Sports-related injury data for the 2005-2006 through 2013-2014 academic years from a national convenience sample of high schools participating in the National High School Sports-Related Injury Surveillance Study (High School Reporting Information Online [RIO]) were analyzed. Results: Certified athletic trainers participating in High School RIO reported 115 of 1246 (9.2%) elbow injuries as elbow dislocations. A total of 30,415,179 athlete exposures (AEs) were reported during the study period, resulting in a dislocation rate of 0.38 per 100,000 AEs. The majority of the dislocations resulted from boys’ wrestling (46.1%) and football (37.4%). Elbow dislocation rates were higher in competition than in practice. Also, 91.3% of dislocations occurred in boys’ sports. Among both boys (60.4%) and girls (88.9%), the majority of injuries occurred during varsity sports activities. Contact with another person was the most common injury mechanism (46.9%), followed by contact with the playing surface (46.0%). Dislocations more commonly resulted in removal from play for more than 3 weeks (23.4% vs 6.9%, respectively) or medical disqualification (36.9% vs 7.0%, respectively) compared with other elbow injuries. Dislocations were also more likely to result in surgical treatment than other elbow injuries (13.6% vs 4.7%, respectively). Conclusion: In high school athletes, elbow dislocations result in longer removal from play and are more likely to require surgical treatment than nondislocation-associated elbow injuries. Rates and patterns of elbow dislocations vary by sport. In high-risk sports, focused sport-specific prevention strategies may help to decrease the rates and severity of elbow dislocation injuries.

Demographic profile of families and children in the Study to Explore Early Development (SEED): Case-control study of autism spectrum disorder

BACKGROUND The Study to Explore Early Development (SEED) is designed to enhance knowledge of autism spectrum disorder characteristics and etiologies. OBJECTIVE This paper describes the demographic profile of enrolled families and examines sociodemographic differences between children with autism spectrum disorder and children with other developmental problems or who are typically developing. METHODS This multi-site case-control study used health, education, and birth certificate records to identify and enroll children aged 2-5 years into one of three groups: 1) cases (children with autism spectrum disorder), 2) developmental delay or disorder controls, or 3) general population controls. Study group classification was based on sampling source, prior diagnoses, and study screening tests and developmental evaluations. The childs primary caregiver provided demographic characteristics through a telephone (or occasionally face-to-face) interview. Groups were compared using ANOVA, chi-squared test, or multinomial logistic regression as appropriate. RESULTS Of 2768 study children, sizeable proportions were born to mothers of non-White race (31.7%), Hispanic ethnicity (11.4%), and foreign birth (17.6%); 33.0% of households had incomes below the US median. The autism spectrum disorder and population control groups differed significantly on nearly all sociodemographic parameters. In contrast, the autism spectrum disorder and developmental delay or disorder groups had generally similar sociodemographic characteristics. CONCLUSIONS SEED enrolled a sociodemographically diverse sample, which will allow further, in-depth exploration of sociodemographic differences between study groups and provide novel opportunities to explore sociodemographic influences on etiologic risk factor associations with autism spectrum disorder and phenotypic subtypes.

Cheerleading Injuries in United States High Schools

BACKGROUND AND OBJECTIVES: Approximately 400 000 students participate in US high school cheerleading annually, including 123 386 involved in competitive spirit squads. The degree of athleticism and the difficulty of cheerleading skills have increased in recent decades, renewing safety concerns. This study describes the epidemiology of high school cheerleading injuries and compares cheerleading injury rates and patterns relative to other sports. METHODS: Data collected by the longitudinal, National High School Sports-Related Injury Surveillance Study from 2009/2010 through 2013/2014 were analyzed. RESULTS: Injury rates in cheerleading ranked 18th of 22 sports, with an overall injury rate of 0.71 per 1000 athlete-exposures (AEs). Competition (0.85) and practice (0.76) injury rates were similar, whereas performance rates were lower (0.49). Although 96.8% of injured cheerleaders were girls, the overall injury rate was higher in boys (1.33 vs 0.69, rate ratio [RR]: 1.93, 95% confidence interval [CI]: 1.30–2.88). Although concussions were the most common cheerleading injury (31.1% of injuries), concussion rates were significantly lower in cheerleading (2.21 per 10 000 athlete-exposures) than all other sports combined (3.78; RR: 0.58, 95% CI: 0.51–0.66) and all other girls’ sports (2.70; RR: 0.82, 95% CI: 0.72–0.93). Over half of all injuries occurred during stunts (53.2%). CONCLUSIONS: Although safety remains a concern among cheerleaders, overall injury rates are lower than most other high school sports. Although overall injury rates are relatively low, cheerleading injuries may be more severe when they do occur. A detailed knowledge of cheerleading injury patterns relative to other sports is needed to drive targeted, evidence-based prevention efforts.

Epidemiology of Shoulder Dislocations in High School and Collegiate Athletics in the United States: 2004/2005 Through 2013/2014

Background: Shoulder dislocations occur frequently in athletes across a variety of sports. This study provides an updated descriptive epidemiological analysis of shoulder dislocations among high school and college athletes and compares injury rates and patterns across these age groups. Hypothesis: There would be no difference in injury rates/patterns between high school and college athletes. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Shoulder dislocation data from the High School Reporting Information Online (RIO) and the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) databases were analyzed from the 2004/2005 through 2013/2014 (NCAA) or 2005/2006 through 2013/2014 (RIO) academic years in 11 different sports. Rate ratios (RRs) and injury proportion ratios (IPRs) were calculated to make comparisons between age groups. Results: During the study period, 598 shoulder dislocations were reported during 29,249,482 athlete-exposures (AEs) among high school athletes, for an overall shoulder dislocation rate of 2.04 per 100,000 AEs; 352 shoulder dislocations were reported during 13,629,533 AEs among college athletes, for an overall injury rate of 2.58 per 100,000 AEs. College athletes had a higher rate of shoulder dislocation than high school athletes (RR, 1.26; 95% CI, 1.11-1.44). However, the injury rate in football was lower in collegiate than high school athletes (RR, 0.52; 95% CI, 0.43-0.62). Surgery was performed to correct 28.0% of high school and 29.6% of college shoulder dislocations. Shoulder dislocations resulted in longer return-to-play times than other shoulder injuries. Conclusion: Overall, shoulder dislocation rates were higher among collegiate than high school athletes. This may be due to greater contact forces involved in sports at higher levels of play, although the increased rate in high school football warrants additional research. Clinical Relevance: Higher shoulder dislocation rates within collegiate athletics are likely due to the higher level of intensity at this level of play, with stronger and faster athletes resulting in more forceful collisions.

Epidemiologic comparisons of soccer-related injuries presenting to emergency departments and reported within high school and collegiate settings

BackgroundFew studies compare sports injury patterns in different settings. This study described the epidemiology of soccer injuries presenting to emergency departments (EDs) and compared injuries presenting to EDs to injuries presenting to collegiate and high school athletic trainers (ATs).MethodsSoccer-related injuries (product code 1267) in the National Electronic Injury Surveillance System (NEISS) that were sustained by individuals at least two years of age in 2004–2013 were included. High School Reporting Information Online (HS RIO) data for high school soccer injuries during the 2005/06–2013/14 academic years were compared to NEISS data for those aged 14–17 years in 2005–2013. National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) data for collegiate soccer injuries during the 2009/10–2013/14 academic years were compared to NEISS data for those aged 18–22 years in 2009–2013. All datasets included weights to calculate national estimates. Injury proportion ratios (IPRs) with 95% confidence intervals (CIs) compared nationally estimated injury distributions between the HS RIO/NCAA-ISP and NEISS data subsets.ResultsDuring the study period, 63,258 soccer-related injuries were captured by NEISS, which translates to an estimated 2,039,250 injuries seen at US EDs nationwide. Commonly injured body parts included the head/face (19.1%), ankle (17.6%), hand/wrist (15.3%), and knee (12.2%). Common diagnoses included sprains/strains (34.0%), fractures (22.2%), and contusions (17.7%). Compared to their respective age ranges in NEISS, sprains/strains comprised a larger proportion of injuries in HS RIO (48.3% vs. 33.7%; IPR = 1.38; 95% CI: 1.33, 1.42) and NCAA-ISP (51.3% vs. 37.0%; IPR = 1.39; 95% CI: 1.31, 1.46). In contrast, fractures comprised a smaller proportion of injuries in HS RIO than in NEISS (7.5% vs. 18.6%; IPR = 0.43; 95% CI: 0.39, 0.47) and NCAA-ISP (2.8% vs. 15.7%; IPR = 0.18; 95% CI: 0.14, 0.22).ConclusionsATs more commonly reported injuries that are easily diagnosed and treated (e.g., sprains/strains); EDs more commonly reported injuries with longer recovery times and rehabilitation (e.g., fractures). Although ED surveillance data can identify the most severe sports-related injuries, high school and college sports surveillance may better describe the breadth of sports-related injuries. Our findings may provide further support for school-based sports medicine professionals, but further research is needed to comprehensively examine the potential economic and health-related benefits.

An Epidemiological Comparison of Elbow Injuries Among United States High School Baseball and Softball Players, 2005-2006 Through 2014-2015:

Background: Pitching is a common mechanism of injury in baseball, with known risk factors for elbow injuries among adolescent pitchers. Hypothesis: Elbow injury rates and mechanisms will differ between high school baseball and softball players. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Baseball- and softball-related injury data from the 2005-2006 through 2014-2015 academic years were collected from the High School Reporting Information Online (RIO) Internet-based data collection tool. Athlete-exposure (AE) and injury data were collected by certified athletic trainers. Rate ratios (RRs) were calculated comparing injury rates in the 2 populations. Injury proportion ratios (IPRs) comparing elbow injuries in pitchers and nonpitchers were calculated as the proportion of all elbow injuries in pitchers divided by the proportion of all elbow injuries in nonpitchers. Results: A total of 214 elbow injuries in male baseball players occurred over 2,327,774 AEs, for an overall elbow injury rate of 0.92 per 10,000 AEs. A total of 75 elbow injuries were reported in female softball players over 1,731,644 AEs, for an overall rate of 0.43 per 10,000 AEs. The rate of elbow injury was significantly higher for baseball than softball (RR, 2.12; 95% CI, 1.64-2.77). A significantly greater proportion of elbow injuries in baseball were pitching-related compared with those from softball, with 50.2% occurring while pitching in baseball versus 11.0% in softball (IPR, 4.58; 95% CI, 2.35-8.93). If all injuries occurring during pitching were removed from both sports, the difference in elbow injury rate for baseball and softball would no longer be significant (RR, 1.19; 95% CI, 0.88-1.62). Conclusion: The rate of elbow injuries is significantly higher in baseball than softball. This is attributable to differences in rates of pitching-related injuries between these 2 groups. Clinical Relevance: These results demonstrate that overhand pitching increases risk of elbow injury in high school athletes.

Status of High Body Weight Among Nurse-Family Partnership Children

Purpose: Increased prevalence of high levels of body weight in early childhood has become a public health concern, given its potential association with adult obesity and related comorbidities. Both socioeconomic status and race-ethnicity are related to increased prevalence. The purpose of this study was to identify additional risk factors common to children of low-income families; and to guide quality improvement initiatives within home visiting programs, potentially fostering more desirable physical development outcomes. Study Design and Methods: A cohort of children (n = 14,318) of all mothers enrolled in Nurse–Family Partnership between 2007 and 2010 was evaluated. Measures consisted of demographics, health behaviors, and physical growth metrics collected by specially educated nurses during the course of home visits that also delivered the program model. Measures of weight (W) versus length (L) were converted to percentiles using the Centers for Disease Control and Prevention–World Health Organization norms with high W/L (≥97.7th percentile) defining a binary outcome. Multiple logistic regression modeling was then used to derive risk models for that outcome. Results: Across each of the four time points for body measures (childs age 6, 12, 18, and 24 months), race-ethnicity, prepregnancy body mass index (BMI), maternal weight gain, and breastfeeding duration emerged as common risk factors. Clinical Implications: Moderation of weight gain during pregnancy, extending breastfeeding duration, and normalization of BMI before subsequent pregnancies may potentially serve as means of lowering the prevalence of high body weight levels in young children of low-income families served by home visitors.

Head impact locations in US high school boys’ and girls’ soccer concussions, 2012/13-2015/16

This study describes concussions and concussion-related outcomes sustained by high school soccer players by head impact location, sex, and injury mechanism. Data were obtained for the 2012/13-2015/16 school years from the National High School Sports-Related Injury Surveillance System, High School RIO™. This Internet-based sports injury surveillance system captures data reported by athletic trainers from an annual average of 162 U.S. high schools. Data were analyzed to describe circumstances of soccer concussion (e.g., symptomology, symptom resolution, and return-to-play time) by impact location (i.e., front- [face included], back-, side-, and top-of-the-head) and sex. Most concussions were from front-of-the-head impacts (boys, 30.5%; girls, 34.0%). Overall, 4.1 ± 2.2 and 4.6 ± 2.3 symptoms were reported in boys and girls, respectively. In boys, symptom frequency was not associated with head impact location (p = 0.66); an association was found in girls (p = 0.02), with the highest symptom frequency reported in top-of-the-head impacts (5.4 ± 2.2). Head impact location was not associated with symptom resolution time (boys, p = 0.21; girls, p = 0.19) or return-to-play time (boys, p = 0.18; girls, p = 0.07). Heading was associated with 28.0% and 26.5% of concussions in boys and girls, respectively. Most player-player contact concussions during heading occurred from side-of-the-head impacts (boys, 49.4%; girls, 43.2%); most heading-related ball contact concussions occurred from front-of-the-head (boys, 41.4%; girls, 42.6%) and top-of-the-head (boys, 34.5%; girls, 36.9%) impacts. Head impact location was generally independent of symptom resolution time, return-to-play time, and recurrence among high school soccer concussions. However, impact location may be associated with reported symptom frequency. Further, many of these clinical concussion descriptors were associated with sex.