Epidemiology of Exertional Heat Illnesses in Youth, High School, and College Football.

INTRODUCTION: Data on exertional heat illness (EHI) in youth football are limited and have not been compared across competition levels. PURPOSE: This study describes the epidemiology of EHI events in youth, high school (HS), and college football in the 2012-2014 seasons. METHODS: One hundred and eighteen youth teams (players age 5-14 yr), 96 HS programs (~14-18 yr), and 34 college programs (~18-23 yr) participated. During games and practices, athletic trainers recorded EHI events and athlete exposures (AE), defined as one athlete participating in one game/practice. We calculated the number of reported EHI by time in season, game/practice, and need for emergency transportation. EHI rates, risk, included rate ratios (IRR), and risk ratios (RR) with 95% confidence intervals (CI) were calculated in 2015. RESULTS: EHI rates for youth, HS, and college football were 1.82, 0.57, and 1.67/10,000 AE, respectively. Rates were highest during the preseason (youth: 2.76; HS: 1.47; college: 3.66/10,000 AE). Game rates were higher than practice rates in youth (4.04 vs 1.22/10,000 AE; IRR = 3.31; 95% CI, 1.75-6.26) and college (4.42 vs 1.38/10,000 AE; IRR = 3.21; 95% CI, 2.00-5.16); the practice rate was higher than the game rate in HS (0.63 vs 0.27/10,000 AE; IRR = 2.33; 95% CI, 1.01-5.38). The EHI risk was higher in college (0.9%) than in youth (0.6%; RR = 1.59; 95% CI, 1.06-2.37) and HS (0.5%; RR = 2.01; 95% CI, 1.43-2.81). Common EHI events included heat cramps (youth: 15.8%; HS: 28.6%; college: 45.6%), heat exhaustion (youth: 42.1%; HS: 32.9%; college: 20.0%), and dehydration (youth: 31.6%; HS: 28.6%; college: 28.9%). CONCLUSIONS: EHI risk was low. Higher preseason football EHI rates across levels emphasize developing and continually modifying preseason heat acclimatization policies. Lower EHI rates in HS games and youth practices may be attributable to night events, suggesting the importance of modifying/canceling events based on environmental conditions.

Epidemiology of National Collegiate Athletic Association Men's and Women's Cross-Country Injuries, 2009-2010 Through 2013-2014.

CONTEXT: Recent injury-surveillance data for collegiate-level cross-country athletes are limited. OBJECTIVE: To describe the epidemiology of National Collegiate Athletic Association (NCAA) men's and women's cross-country injuries during the 2009-2010 through 2013-2014 academic years. DESIGN: Descriptive epidemiology study. SETTING: Aggregate injury and exposure data collected from 25 men's and 22 women's cross-country programs, providing 47 and 43 seasons of data, respectively. PATIENTS OR OTHER PARTICIPANTS: Collegiate student-athletes participating in men's and women's cross-country during the 2009-2010 through 2013-2014 academic years. MAIN OUTCOME MEASURE(S): Injury rates; injury rate ratios (RRs); injury proportions by body site, diagnosis, and apparatus; and injury proportion ratios were reported with 95% confidence intervals (CIs). RESULTS: The Injury Surveillance Program captured 216 injuries from men's cross-country and 260 injuries from women's cross-country, leading to injury rates of 4.66/1000 athlete-exposures (AEs) for men (95% CI = 4.04, 5.28) and 5.85/1000 AEs for women (95% CI = 5.14, 6.56). The injury rate in women's cross-country was 1.25 times that of men's cross-country (95% CI = 1.05, 1.50). Most injuries affected the lower extremity (men = 90.3%, women = 81.9%). The hip/groin-injury rate in women (0.65/1000 AEs) was higher than that in men (0.15/1000 AEs; RR = 4.32; 95% CI = 1.89, 9.85). The ankle-injury rate in men (0.60/1000 AEs) was higher than that in women (0.29/1000 AEs; RR = 2.07; 95% CI = 1.07, 3.99). Common diagnoses were strains (men = 19.9%, women = 20.4%) and inflammation (men = 18.1%, women = 23.8%). The majority of injuries were classified as overuse (men = 57.6%, women = 53.3%). CONCLUSIONS: Consistent with prior research, injury distributions varied between male and female athletes, and the injury rate among females was higher. Understanding the epidemiology of these cross-country injuries may be important for developing appropriate preventive interventions.

Injury Rates in Age-Only Versus Age-and-Weight Playing Standard Conditions in American Youth Football.

BACKGROUND: American youth football leagues are typically structured using either age-only (AO) or age-and-weight (AW) playing standard conditions. These playing standard conditions group players by age in the former condition and by a combination of age and weight in the latter condition. However, no study has systematically compared injury risk between these 2 playing standards. PURPOSE: To compare injury rates between youth tackle football players in the AO and AW playing standard conditions. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Athletic trainers evaluated and recorded injuries at each practice and game during the 2012 and 2013 football seasons. Players (age, 5-14 years) were drawn from 13 recreational leagues across 6 states. The sample included 4092 athlete-seasons (AW, 2065; AO, 2027) from 210 teams (AW, 106; O, 104). Injury rate ratios (RRs) with 95% CIs were used to compare the playing standard conditions. Multivariate Poisson regression was used to estimate RRs adjusted for residual effects of age and clustering by team and league. There were 4 endpoints of interest: (1) any injury, (2) non-time loss (NTL) injuries only, (3) time loss (TL) injuries only, and (4) concussions only. RESULTS: Over 2 seasons, the cohort accumulated 1475 injuries and 142,536 athlete-exposures (AEs). The most common injuries were contusions (34.4%), ligament sprains (16.3%), concussions (9.6%), and muscle strains (7.8%). The overall injury rate for both playing standard conditions combined was 10.3 per 1000 AEs (95% CI, 9.8-10.9). The TL injury, NTL injury, and concussion rates in both playing standard conditions combined were 3.1, 7.2, and 1.0 per 1000 AEs, respectively. In multivariate Poisson regression models controlling for age, team, and league, no differences were found between playing standard conditions in the overall injury rate (RRoverall, 1.1; 95% CI, 0.4-2.6). Rates for the other 3 endpoints were also similar (RRNTL, 1.1 [95% CI, 0.4-3.0]; RRTL, 0.9 [95% CI, 0.4-1.9]; RRconcussion, 0.6 [95% CI, 0.3-1.4]). CONCLUSION: For the injury endpoints examined in this study, the injury rates were similar in the AO and AW playing standards. Future research should examine other policies, rules, and behavioral factors that may affect injury risk within youth football.

Methods and Descriptive Epidemiology of Services Provided by Athletic Trainers in High Schools: The National Athletic Treatment, Injury and Outcomes Network Study.

CONTEXT: Research is limited on the extent and nature of the care provided by athletic trainers (ATs) to student-athletes in the high school setting. OBJECTIVE: To describe the methods of the National Athletic Treatment, Injury and Outcomes Network (NATION) project and provide the descriptive epidemiology of AT services for injury care in 27 high school sports. DESIGN: Descriptive epidemiology study. SETTING: Athletic training room (ATR) visits and AT services data collected in 147 high schools from 26 states. PATIENTS OR OTHER PARTICIPANTS: High school student-athletes participating in 13 boys' sports and 14 girls' sports during the 2011-2012 through 2013-2014 academic years. MAIN OUTCOME MEASURE(S): The number of ATR visits and individual AT services, as well as the mean number of ATR visits (per injury) and AT services (per injury and ATR visit) were calculated by sport and for time-loss (TL) and non-time-loss (NTL) injuries. RESULTS: Over the 3-year period, 210 773 ATR visits and 557 381 AT services were reported for 50 604 injuries. Most ATR visits (70%) were for NTL injuries. Common AT services were therapeutic activities or exercise (45.4%), modalities (18.6%), and AT evaluation and reevaluation (15.9%), with an average of 4.17 ± 6.52 ATR visits and 11.01 ± 22.86 AT services per injury. Compared with NTL injuries, patients with TL injuries accrued more ATR visits (7.76 versus 3.47; P < .001) and AT services (18.60 versus 9.56; P < .001) per injury. An average of 2.24 ± 1.33 AT services were reported per ATR visit. Compared with TL injuries, NTL injuries had a larger average number of AT services per ATR visit (2.28 versus 2.05; P < .001). CONCLUSIONS: These findings highlight the broad spectrum of care provided by ATs to high school student-athletes and demonstrate that patients with NTL injuries require substantial amounts of AT services.

Comprehensive Coach Education and Practice Contact Restriction Guidelines Result in Lower Injury Rates in Youth American Football.

BACKGROUND: Research evaluating the effect of comprehensive coach education and practice contact restriction in youth football injury rates is sparse. In 2012, USA Football released their Heads Up Football coaching education program (HUF), and Pop Warner Football (PW) instituted guidelines to restrict contact during practice. PURPOSE: To compare injury rates among youth football players aged 5 to 15 years by whether their leagues implemented HUF and/or were PW-affiliated. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2014 youth football season. Players were drawn from 10 leagues across 4 states. The non-Heads Up Football (NHUF) group consisted of 704 players (none of whom were PW-affiliated) from 29 teams within 4 leagues. The HUF+PW group consisted of 741 players from 27 teams within 2 leagues. The HUF-only group consisted of 663 players from 44 teams within 4 leagues. Injury rates and injury rate ratios (IRRs) were reported with 95% CIs. RESULTS: A total of 370 injuries were reported during 71,262 athlete-exposures (AEs) (rate, 5.19/1000 AEs). Compared with the NHUF group (7.32/1000 AEs), the practice injury rates were lower for the HUF+PW group (0.97/1000 AEs; IRR, 0.13; 95% CI, 0.08-0.21) and the HUF-only group (2.73/1000 AEs; IRR, 0.37; 95% CI, 0.26-0.53). Compared with the NHUF group (13.42/1000 AEs), the game injury rate was lower for the HUF+PW group (3.42/1000 AEs; IRR, 0.25; 95% CI, 0.15-0.44) but not for the HUF-only group (13.76/1000 AEs; IRR, 1.02; 95% CI, 0.73-1.43). Also, the HUF+PW game injury rate was lower than that of HUF-only (IRR, 0.20; 95% CI, 0.12-0.36). Higher injury rates were typically found in those aged 11 to 15 years compared with those aged 5 to 10 years. However, stronger effects related to HUF implementation and PW affiliation were seen among 11- to 15-year-olds. When restricted to concussions only, the sole difference was found between the practice concussion rates among 11- to 15-year-olds in the HUF+PW (0.14/1000 AEs) and NHUF groups (0.79/1000 AEs) (IRR, 0.18; 95% CI, 0.04-0.85). CONCLUSION: These findings support comprehensive coach education and practice contact restrictions as effective methods of injury mitigation. Future research should continue evaluating similar programming within other levels of competition and sports.

Epidemiology of National Collegiate Athletic Association Women's Gymnastics Injuries, 2009-2010 Through 2013-2014.

CONTEXT: Recent injury-surveillance data for collegiate-level women's gymnastics are limited. In addition, researchers have not captured non-time-loss injuries (ie, injuries resulting in restriction of participation <1 day). OBJECTIVE: To describe the epidemiology of National Collegiate Athletic Association (NCAA) women's gymnastics injuries during the 2009-2010 through 2013-2014 academic years. DESIGN: Descriptive epidemiology study. SETTING: Aggregate injury and exposure data collected from 11 women's gymnastics programs providing 28 seasons of data. PATIENTS OR OTHER PARTICIPANTS: Collegiate student-athletes participating in women's gymnastics during the 2009-2010 through 2013-2014 academic years. INTERVENTION(S): Women's gymnastics data from the NCAA Injury Surveillance Program (ISP) during the 2009-2010 through 2013-2014 academic years were analyzed. MAIN OUTCOME MEASURE(S): Injury rates; injury rate ratios; injury proportions by body site, diagnosis, and apparatus; and injury proportion ratios were reported with 95% confidence intervals (CIs). RESULTS: The ISP captured 418 women's gymnastics injuries, a rate of 9.22/1000 athlete-exposures (AEs; 95% CI = 8.33, 10.10). The competition injury rate (14.49/1000 AEs) was 1.67 times the practice injury rate (8.69/1000 AEs; 95% CI = 1.27, 2.19). When considering time-loss injuries only, the injury rate during this study period (3.62/1000 AEs) was lower than rates reported in earlier NCAA ISP surveillance data. Commonly injured body sites were the ankle (17.9%, n = 75), lower leg/Achilles tendon (13.6%, n = 57), trunk (13.4%, n = 56), and foot (12.4%, n = 52). Common diagnoses were ligament sprain (20.3%, n = 85) and muscle/tendon strain (18.7%, n = 78). Overall, 12.4% (n = 52) of injuries resulted in time loss of more than 3 weeks. Of the 291 injuries reported while a student-athlete used an apparatus (69.6%), most occurred during the floor exercise (41.9%, n = 122) and on the uneven bars (28.2%, n = 82). CONCLUSIONS: We observed a lower time-loss injury rate for women's gymnastics than shown in earlier NCAA ISP surveillance data. Safety initiatives in women's gymnastics, such as "sting mats," padded equipment, and a redesigned vault table, may have contributed to minimizing the frequency and severity of injury.

The National Athletic Treatment, Injury and Outcomes Network (NATION): Methods of the Surveillance Program, 2011-2012 Through 2013-2014.

CONTEXT: Previous epidemiologic researchers have examined time-loss (TL) injuries in high school student-athletes, but little is known about the frequency of non-time-loss (NTL) injuries in these athletes. OBJECTIVE: To describe the methods of the National Athletic Treatment, Injury and Outcomes Network (NATION) Surveillance Program and provide descriptive epidemiology of TL and NTL injuries across athletes in 27 high school sports. DESIGN: Descriptive epidemiology study. SETTING: Aggregate injury and exposure data collected from 147 high schools in 26 states. PATIENTS OR OTHER PARTICIPANTS: High school student-athletes participating in 13 boys' sports and 14 girls' sports during the 2011-2012 through 2013-2014 academic years. MAIN OUTCOME MEASURE(S): Athletic trainers documented injuries and exposures using commercially available injury-tracking software packages. Standard injury-tracking software was modified by the software vendors to conform to the surveillance needs of this project. The modified software exported a set of common data elements, stripped of personally identifiable information, to a centralized automated verification and validation system before they were included in the centralized research database. Dependent measures were injury and exposure frequencies and injury rates with 95% confidence intervals stratified by sport, sex, and injury type (TL or NTL). RESULTS: Over the 3-year period, a total of 2337 team seasons across 27 sports resulted in 47 014 injuries and 5 146 355 athlete-exposures. The NTL injuries accounted for 38 765 (82.45%) and TL injuries for 8249 (17.55%) of the total. CONCLUSIONS: The NTL injuries accounted for a substantial amount of the total number of injuries sustained by high school student-athletes. This project demonstrates the feasibility of creating large-scale injury surveillance systems using commercially available injury-tracking software.

Incidence of Concussion During Practice and Games in Youth, High School, and Collegiate American Football Players.

IMPORTANCE: A report by the Institute of Medicine called for comprehensive nationwide concussion incidence data across the spectrum of athletes aged 5 to 23 years. OBJECTIVE: To describe the incidence of concussion in athletes participating in youth, high school, and collegiate American football. DESIGN, SETTING, AND PARTICIPANTS: Data were collected by athletic trainers at youth, high school, and collegiate football practices and games to create multiple prospective observational cohorts during the 2012 and 2013 football seasons. Data were collected from July 1, 2012, through January 31, 2013, for the 2012 season and from July 1, 2013, through January 31, 2014, for the 2013 season. The Youth Football Surveillance System included 118 youth football teams, providing 4092 athlete-seasons. The National Athletic Treatment, Injury and Outcomes Network program included 96 secondary school football programs, providing 11 957 athlete-seasons. The National Collegiate Athletic Association Injury Surveillance Program included 24 member institutions, providing 4305 athlete-seasons. EXPOSURES: All injuries regardless of severity, including concussions, and athlete exposure information were documented by athletic trainers during practices and games. MAIN OUTCOMES AND MEASURES: Injury rates, injury rate ratios, risks, risk ratios, and 95% CIs were calculated. RESULTS: Concussions comprised 9.6%, 4.0%, and 8.0% of all injuries reported in the Youth Football Surveillance System; National Athletic Treatment, Injury and Outcomes Network; and National Collegiate Athletic Association Injury Surveillance Program, respectively. The game concussion rate was higher than the practice concussion rate across all 3 competitive levels. The game concussion rate for college athletes (3.74 per 1000 athlete exposures) was higher than those for high school athletes (injury rate ratio, 1.86; 95% CI, 1.50-2.31) and youth athletes (injury rate ratio, 1.57; 95% CI, 1.17-2.10). The practice concussion rate in college (0.53 per 1000 athlete exposures) was lower than that in high school (injury rate ratio, 0.80; 95% CI, 0.67-0.96). Youth football had the lowest 1-season concussion risks in 2012 (3.53%) and 2013 (3.13%). The 1-season concussion risk was highest in high school (9.98%) and college (5.54%) in 2012. CONCLUSIONS AND RELEVANCE: Football practices were a major source of concussion at all 3 levels of competition. Concussions during practice might be mitigated and should prompt an evaluation of technique and head impact exposure. Although it is more difficult to change the intensity or conditions of a game, many strategies can be used during practice to limit player-to-player contact and other potentially injurious behaviors.

Association of equipment worn and concussion injury rates in National Collegiate Athletic Association football practices: 2004-2005 to 2008-2009 academic years.

BACKGROUND: The epidemiology of football-related concussions has been extensively examined. However, although football players experience more at-risk exposure time during practices than competitions, there is a dearth of literature examining the nature of the activities or equipment worn during practice. In particular, varying levels of equipment worn during practices may place players at varying levels of risk for concussion. PURPOSE: To describe the epidemiology of NCAA men's football concussions that occurred during practices from the 2004-2005 to 2008-2009 academic years by amount of equipment worn. STUDY DESIGN: Descriptive epidemiology study. METHODS: Men's collegiate football data from the National Collegiate Athletic Association Injury Surveillance System (NCAA ISS) during the 5-year study period were analyzed. Injury rates and injury rate ratios (RRs) were reported with 95% confidence intervals. RESULTS: During the study period, 795 concussions were reported during practices, resulting in an injury rate of 0.39 per 1000 athlete-exposures (AEs) (95% CI, 0.36-0.42). Among NCAA divisions, Division III had the highest concussion rate (0.54/1000 AEs), followed by Division I (0.34/1000 AEs) and Division II (0.24/1000 AEs) (all P values for RRs comparing divisions<.001). Most concussions in practice occurred when players were fully padded (69.9%), followed by wearing shells (23.5%) and helmets only (1.9%). The practice concussion rate was higher in fully padded practices (0.66/1000 AEs) compared with practices when shells were worn (0.33/1000 AEs; RR=1.99 [95% CI, 1.69-2.35]; P<.001) and practices when only helmets were worn (0.03/1000 AEs; RR=22.39 [95% CI, 13.41-37.39]; P<.001). The practice concussion rate of the preseason (0.76/1000 AEs) was higher than that of the regular season (0.18/1000 AEs; RR=4.14 [95% CI, 3.55-4.83]; P<.001) and that of postseason (0.25/1000 AEs; RR=3.02 [95% CI, 1.95-4.67]; P<.001). The types of practice with the highest concussion rate were scrimmages (1.55/1000 AEs). Although only 3 concussions were sustained during scrimmage practices in which players wore shells, the concussion rate (2.84/1000 AEs) was higher than all other reported rates. CONCLUSION: Practice concussion rates are highest during fully padded practices, preseason practices, and scrimmages, suggesting that the nature, focus, and intensity of football practices affect concussion risk. In addition, coaching staff should continue to closely monitor player safety during scrimmages. Meanwhile, future surveillance should examine whether removing scrimmages, particularly those that are not fully padded, will meaningfully reduce the incidence and rate of concussions.

Epidemiology of National Collegiate Athletic Association men's and women's swimming and diving injuries from 2009/2010 to 2013/2014.

BACKGROUND: Recent injury data for collegiate-level swimming and diving are limited. This study describes the epidemiology of men's and women's swimming and diving injuries reported by the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) during the 2009/2010 to 2013/2014 academic years. METHODS: Injuries and athlete-exposure (AE) data reported within 9 men's and 13 women's swimming and diving programmes were analysed. Injury rates, injury rate ratios (IRR), and injury proportions by body site, diagnosis and mechanism were reported with 95% CIs. RESULTS: The ISP captured 149 and 208 injuries for men's and women's swimming and diving, respectively, leading to injury rates of 1.54/1000 and 1.71/1000 AEs. Among females, divers had a higher injury rate (2.49/1000 AEs) than swimmers (1.63/1000 AEs; IRR=1.53; 95% CI 1.07 to 2.19). Injury rates for male divers (1.94/1000 AEs) and swimmers (1.48/1000 AEs) did not differ (IRR=1.33; 95% CI 0.85 to 2.31). Most injuries occurred to the shoulder, resulted in strains and were classified as overuse or non-contact. Female swimmers had a higher overuse injury rate (1.04/1000 AEs) than male swimmers (0.66/1000 AEs; IRR=1.58; 95% CI 1.14 to 2.19). Overuse injury rates for female divers (0.54/1000 AEs) and male divers (0.46/1000 AEs) did not differ (IRR=1.16; 95% CI 0.40 to 3.34). Injury rates in 2012/2013-2013/2014 were lower than those in 2009/2010-2011/2012 for women's swimming (IRR=0.70; 95% CI 0.52 to 0.95) and diving (IRR=0.56; 95% CI 0.30 to 1.08), respectively. No time trends existed for men's swimmers or divers. CONCLUSIONS: Shoulder, strain and overuse injuries were common in collegiate men's and women's swimming and diving. Female swimmers were more likely to suffer an overuse injury than male swimmers. In addition, divers may have higher injury rates than swimmers, although small reported numbers warrant additional research.

Comprehensive Coach Education Reduces Head Impact Exposure in American Youth Football.

BACKGROUND: Despite little evidence that defines a threshold of head impact exposure or that participation in youth sports leads to long-term cognitive impairments, it is prudent to identify methods of reducing the frequency of head impacts. PURPOSE: To compare the mean number of head impacts between youth football players in practice and games between leagues that implemented the Heads Up Football (HUF) educational program and those that did not (NHUF). STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: During the 2014 season, head impact exposure was measured using xPatch accelerometers from 70 youth football players aged 8 to 15 years from 5 leagues. Data were collected during both games and practices. The NHUF group comprised 32 players from 8 teams within 3 leagues. The HUF group comprised 38 players from 7 teams within 2 leagues. Independent-sample t tests evaluated differences in head impact exposure across groups (ie, HUF and NHUF). RESULTS: Players (mean ± SD: age, 11.7 ± 1.4 years; height, 152.2 ± 10.5 cm; weight, 51.6 ± 9.6 kg) experienced a total of 7478 impacts over 10g, of which 4250 (56.8%) and 3228 (43.2%) occurred in practices and games, respectively. The majority of impacts occurred within the NHUF group (62.0%), followed by the HUF group (38.0%). With a 10g impact threshold, the mean number of impacts during practice per individual event was lower in the HUF group (mean ± SD, 5.6 ± 2.9) than in the NHUF group (mean ± SD, 8.9 ± 3.1; difference, 3.4; 95% CI, 2.9-3.9). This difference was attenuated when the threshold was changed to 20g but remained significant (difference, 1.0; 95% CI, 0.7-1.3). At both the 10g and 20g impact thresholds, no differences were found in games. CONCLUSION: Players who participated in HUF leagues accumulated fewer head impacts per practice at both the 10g and 20g thresholds. Youth football leagues should consider the HUF educational program, while exploring additional interventions, to help reduce the number of head impacts in players.