Sara L. Dalton

Epidemiology of Hamstring Strains in 25 NCAA Sports in the 2009-2010 to 2013-2014 Academic Years

Background: The epidemiology of hamstring strains among student-athletes has been extensively researched. However, there is a paucity of recent data describing patterns of hamstring strains. Purpose: To describe the epidemiology of hamstring strains in 25 National Collegiate Athletic Association (NCAA) championship sports. Study Design: Descriptive epidemiology study. Methods: Hamstring strains data were analyzed from the NCAA Injury Surveillance Program during the 2009-2010 to 2013-2014 academic years. Hamstring strain injury rates, rate ratios (RRs), and injury proportion ratios were reported with 95% CIs. Results: During the study period, 1142 hamstring strains were reported, leading to an injury rate of 3.05 per 10,000 athlete-exposures (AEs). Most hamstring strains occurred during practices (68.2%). However, the competition rate (5.24 per 10,000 AEs) was larger than the practice rate (2.56 per 10,000 AEs; RR = 2.05; 95% CI, 1.81-2.32). A slight majority occurred during the regular season (52.9%). However, the preseason rate (5.00 per 10,000 AEs) was larger than the regular season/postseason rate (2.34 per 10,000 AEs; RR = 2.14; 95% CI, 1.90-2.40). Men’s football, men’s soccer, and women’s soccer contributed the greatest proportion of hamstring strains (35.3%, 9.9%, and 8.3%, respectively). Most hamstring strains were due to noncontact (72.3%). Of all hamstring strains, 12.6% were recurrent, 37.7% resulted in a time loss of <24 hours, and 6.3% resulted in a time loss >3 weeks. Variations in hamstring strain patterns existed by sport. The hamstring strain rate was larger in men than in women in soccer (RR = 1.60; 95% CI, 1.22-2.11), baseball/softball (RR = 1.66; 95% CI, 1.07-2.59), and indoor track (RR = 1.88; 95% CI, 1.26-2.78). In addition, proportions of hamstring strains that were recurrent were higher among men in most sex-comparable sports, but this difference was not significant. Conclusion: Hamstring strain rates were higher in the preseason and in competition. Student-athletes should be acclimatized to the rigors of preseason participation. Meanwhile, further surveillance should investigate the effectiveness of prospective prevention programs in an effort to reduce the prevalence of initial and recurrent hamstring strain injuries.

Epidemiologic Measures for Quantifying the Incidence of Concussion in National Collegiate Athletic Association Sports

CONTEXT Injury rates compare the relative frequency of sport-related concussions across groups. However, they may not be intuitive to policy makers, parents, or coaches in understanding the likelihood of concussion. OBJECTIVE To describe 4 measures of incidence (athlete-based rate, athlete-based risk, team-based rate, and team-based risk) during the 2011-2012 through 2014-2015 academic years. DESIGN  Descriptive epidemiology study. SETTING Aggregate injury and exposure data collected from the National Collegiate Athletic Association Injury Surveillance Program in 13 sports (mens baseball, basketball, football, ice hockey, lacrosse, soccer, and wrestling and womens basketball, ice hockey, lacrosse, soccer, softball, and volleyball). PATIENTS OR OTHER PARTICIPANTS Collegiate student-athletes. MAIN OUTCOME MEASURE(S) Sport-related concussion data from the National Collegiate Athletic Association Injury Surveillance Program during the 2011-2012 through 2014-2015 academic years were analyzed. We calculated concussion rates per 1000 athlete-exposures (AEs), concussion risk, average number of concussions per team, and percentage of teams with at least 1 concussion. RESULTS During the 2011-2012 through 2014-2015 academic years, 1485 concussions were sustained by 1410 student-athletes across 13 sports. Concussion rates ranged from 0.09/1000 AEs in mens baseball to 0.89/1000 AEs in mens wrestling. Concussion risk ranged from 0.74% in mens baseball to 7.92% in mens wrestling. The average ± SD number of concussions per team ranged from 0.25 ± 0.43 in mens baseball to 5.63 ± 5.36 in mens football. The percentage of teams with a concussion ranged from 24.5% in mens baseball to 80.6% in mens football. CONCLUSIONS   Although mens wrestling had a higher concussion rate and risk, mens football had the largest average number of concussions per team and the largest percentage of teams with at least 1 concussion. The risk of concussion, average number of concussions per team, and percentage of teams with concussions may be more intuitive measures of incidence for decision makers. Calculating these additional measures is feasible within existing injury surveillance programs, and this method can be applied to other injury types.

Epidemiology of 3825 injuries sustained in six seasons of National Collegiate Athletic Association men's and women's soccer (2009/2010-2014/2015)

Aim To describe the epidemiology of National Collegiate Athletic Association (NCAA) mens and womens soccer injuries during the 2009/2010–2014/2015 academic years. Methods This descriptive epidemiology study used NCAA Injury Surveillance Program (NCAA-ISP) data during the 2009/2010–2014/2015 academic years, from 44 mens and 64 womens soccer programmes (104 and 167 team seasons of data, respectively). Non-time-loss injuries were defined as resulting in <24 h lost from sport. Injury counts, percentages and rates were calculated. Injury rate ratios (RRs) and injury proportion ratios (IPRs) with 95% CIs compared rates and distributions by sex. Results There were 1554 mens soccer and 2271 womens soccer injuries with injury rates of 8.07/1000 athlete exposures (AE) and 8.44/1000AE, respectively. Injury rates for men and women did not differ in competitions (17.53 vs 17.04/1000AE; RR=1.03; 95% CI 0.94 to 1.13) or practices (5.47 vs 5.69/1000AE; RR=0.96; 95% CI 0.88 to 1.05). In total, 47.2% (n=733) of mens soccer injuries and 47.5% (n=1079) of womens were non-time loss. Most injuries occurred to the lower extremity and were diagnosed as sprains. Women had higher concussion rates (0.59 vs 0.34/1000AE; RR=1.76; 95% CI 1.32 to 2.35) than men. Conclusions Non-time-loss injuries accounted for nearly half of the injuries in mens and womens soccer. Sex differences were found in competition injuries, specifically for concussion. Further study into the incidence, treatment and outcome of non-time-loss injuries may identify a more accurate burden of these injuries.

Comparison of Indiana High School Football Injury Rates by Inclusion of the USA Football “Heads Up Football” Player Safety Coach

Background: In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football’s Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. Purpose: To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Study Design: Cohort study; Level of evidence, 2. Methods: Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The “education only” group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). Results: During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Conclusion: Findings support the PSC as an effective method of injury mitigation in high school football. Future research should seek to replicate this study using larger samples from additional states.

The Epidemiology of Hip/Groin Injuries in National Collegiate Athletic Association Men's and Women's Ice Hockey: 2009-2010 Through 2014-2015 Academic Years.

Background: There is limited research regarding the epidemiology of hip/groin injuries in ice hockey, the majority of which is restricted to time-loss injuries only. Purpose: To describe the epidemiology of hip/groin injuries in collegiate men’s and women’s ice hockey from 2009-2010 through 2014-2015. Study Design: Descriptive epidemiology study. Methods: Hip/groin injury data from the National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) during the 2009-2010 through 2014-2015 seasons were analyzed. Injury rates, rate ratios (RRs), and injury proportion ratios (IPRs) were reported with 95% confidence intervals (CIs). Results: During the 2009-2010 through 2014-2015 seasons, 421 and 114 hip/groin injuries were reported in men’s and women’s ice hockey, respectively, leading to injury rates of 1.03 and 0.78 per 1000 athlete-exposures (AEs), respectively. The hip/groin injury rate was greater in men than in women (RR, 1.32; 95% CI, 1.08-1.63). In addition, 55.6% and 71.1% of hip/groin injuries in men’s and women’s ice hockey, respectively, were non–time loss (NTL) injuries (ie, resulted in participation restriction time <24 hours); 7.6% and 0.9%, respectively, were severe (ie, resulted in participation restriction time >3 weeks). The proportion of hip/groin injuries that were NTL injuries was greater in women than in men (IPR, 1.28; 95% CI, 1.11-1.48). Conversely, the proportion of hip/groin injuries that were severe was greater in men than in women (IPR, 8.67; 95% CI, 1.20-62.73). The most common hip/groin injury diagnosis was strain (men, 67.2%; women, 76.3%). Also, 12 (2.9%) and 3 (2.6%) cases of hip impingement were noted in men’s and women’s ice hockey, respectively. Conclusion: Hip/groin injury rates were greater in men’s than in women’s ice hockey. Time loss varied between sexes, with men sustaining more injuries with time loss over 3 weeks. Despite increasing concerns of femoroacetabular impingement in ice hockey players, few cases of hip impingement were reported in this dataset.

Epidemiology of Hip Flexor and Hip Adductor Strains in National Collegiate Athletic Association Athletes, 2009/2010-2014/2015

Background: Little research has examined the rates and patterns of hip flexor or hip adductor strains in student-athletes in the National Collegiate Athletic Association (NCAA). Purpose: To describe the epidemiology of hip flexor and adductor strains in NCAA athletes during the 2009/2010-2014/2015 academic years. Study Design: Descriptive epidemiology study. Methods: Rates and patterns of hip flexor and adductor strains in collegiate sports were examined in a convenience sample of NCAA varsity teams from 25 sports. Rates and distributions of strains by mechanism, recurrence, and participation restriction time were examined. Injury rate ratios (IRRs) and proportion ratios were calculated to compare rates within and between sports by event type, sex, mechanism, recurrence, and participation restriction time. Results: A total of 770 hip flexor and 621 hip adductor strains were reported, resulting in overall injury rates of 1.60 and 1.29 per 10,000 athlete-exposures (AEs), respectively. In men, the rate of hip flexor strains was 1.81 per 10,000 AEs, and that for hip adductor strains was 1.71 per 10,000 AEs. In women, the rate of hip flexor strains was 1.59 per 10,000 AEs, and the rate of hip adductor strains was 1.15 per 10,000 AEs. The highest rates of strains were found in men’s soccer and men’s ice hockey (range, 2.47-3.77 per 10,000 AEs). Most hip flexor and hip adductor strains occurred in practice, but both had higher rates in competition. In sex-comparable sports, hip flexor strain rates did not differ between the sexes (IRR = 1.14; 95% CI, 0.96-1.36), but the rate of hip adductor strains was higher in men than women (IRR = 1.49; 95% CI, 1.22-1.81). Noncontact was the most common mechanism for both types of strains (hip flexor strains, 59.4%; hip adductor strains, 62.5%); 10.1% of hip flexor strains and 11.1% of hip adductor strains were recurrent. The highest rates of recurrence of both types of strain were found in men’s and women’s ice hockey (range, 16.0%-30.6%). Most hip flexor and hip adductor strains resulted in <1 week of participation restriction (hip flexor strains, 83.8%; hip adductor strains, 82.9%). Conclusion: The NCAA sports with the highest rates of hip flexor and hip adductor strains were men’s soccer and men’s ice hockey. In sex-comparable sports, men had a higher rate of hip adductor, but not hip flexor, strains. Recurrence rates were remarkably high in ice hockey. Male sports teams, especially soccer and ice hockey, should place an emphasis on prevention programs for hip adductor strains. Secondary prevention programs involving thorough rehabilitation and strict return-to-play criteria should be developed and implemented to curb the high recurrence rate of these injuries, particularly in ice hockey.

A 6-year surveillance study of “Stingers” in NCAA American Football

ABSTRACT This study describes the epidemiology of “stinger” injuries in National Collegiate Athletic Association (NCAA) Men’s Football. About 57 NCAA Men’s Football programmes provided 153 team-seasons of injury data to the NCAA Injury Surveillance Programme (NCAA-ISP) during the 2009/2010–2014/2015 academic years. In the study period, 229 “stingers” were reported for an injury rate of 2.04/10,000 athlete-exposures (AE). Most “stingers” were reported during competitions (55.5%) and the preseason (80.3%) and resulted in time loss less than 24 hours (63.8%). One in five (18.8%) were recurrent. Most “stingers” were due to player contact (93.0%), particularly while tackling (36.7%) and blocking (25.8%) and occurred to defensive ends/linebackers (25.8%) and offensive linemen (23.6%). Although previous research reports a large prevalence of “stingers” among football players, the NCAA-ISP reported a relatively low injury rate. The transient nature of pain associated with “stingers” may have contributed to under-reporting, highlighting the need to deduce manners to increase reporting.

The epidemiology of back/neck/spine injuries in National Collegiate Athletic Association men’s and women’s ice hockey, 2009/2010 to 2014/2015

ABSTRACT This study describes the epidemiology of back/neck/spine injuries in National Collegiate Athletic Association (NCAA) men’s and women’s ice hockey. Data from 66 NCAA men’s and 29 women’s ice hockey programmes (total of 147 and 67 team-seasons, respectively) were analysed from the NCAA Injury Surveillance Program during the 2009/2010–2014/2015 academic years. In the study period, 226 and 97 back/neck/spine injuries were reported in men and women, respectively, for injury rates of 0.56 and 0.65/1000 athlete exposures. Injury rates were higher in competitions than practices in men (injury rate ratio [IRR] = 4.22; 95% confidence interval [CI]: 3.24–5.49) and women (IRR = 2.49; 95% CI: 1.67–3.70). Most injuries occurred in the lower back/lumbar spine (men: 52.2%; women: 48.5%). There were notably low rates of fractures and severe spinal injuries for both sexes. This study enhances our understanding of the incidence, mechanisms and factors influencing these injuries and can ultimately lead to more effective injury prevention.

Examining Play Counts and Measurements of Injury Incidence in Youth Football

CONTEXT   Whereas researchers have provided estimates for the number of head impacts sustained within a youth football season, less is known about the number of plays across which such impact exposure occurs. OBJECTIVE   To estimate the number of plays in which youth football players participated during the 2013 season and to estimate injury incidence through play-based injury rates. DESIGN   Descriptive epidemiology study. SETTING   Youth football. PATIENTS OR OTHER PARTICIPANTS   Youth football players (N = 2098; age range, 5-15 years) from 105 teams in 12 recreational leagues across 6 states. MAIN OUTCOME MEASURE(S)   We calculated the average number of athlete-plays per season and per game using independent-samples t tests to compare age groups (5-10 years old versus 11-15 years old) and squad sizes (<20 versus ≥20 players); game injury rates per 1000 athlete-exposures (AEs) and per 10 000 athlete-plays; and injury rate ratios (IRRs) with 95% confidence intervals (CIs) to compare age groups. RESULTS   On average, youth football players participated in 333.9 ± 178.5 plays per season and 43.9 ± 24.0 plays per game. Age groups (5- to 10-year-olds versus 11- to 15-year-olds) did not differ in the average number of plays per season (335.8 versus 332.3, respectively; t2086.4 = 0.45, P = .65) or per game (44.1 versus 43.7, respectively; t2092.3 = 0.38, P = .71). However, players from smaller teams participated in more plays per season (373.7 versus 308.0; t1611.4 = 8.15, P < .001) and per game (47.7 versus 41.4; t1523.5 = 5.67, P < .001). Older players had a greater game injury rate than younger players when injury rates were calculated per 1000 AEs (23.03 versus 17.86/1000 AEs; IRR = 1.29; 95% CI = 1.04, 1.60) or per 10 000 athlete-plays (5.30 versus 4.18/10 000 athlete-plays; IRR = 1.27; 95% CI = 1.02, 1.57). CONCLUSIONS   A larger squad size was associated with a lower average number of plays per season and per game. Increasing youth football squad sizes may help reduce head-impact exposure for individual players. The AE-based injury rates yielded effect estimates similar to those of play-based injury rates.

93 Sex differences in ankle sprain treatments in secondary school student-athletes

Statement of Purpose Determine whether ankle sprain management differed between male and female secondary school athletes. Methods/Approach The National Athletic Treatment, Injury and Outcomes Network (NATION) project collected athletic training room (ATR) visits and AT services data from 27 sports in 147 secondary schools from 26 states from 2011–2012 through 2013–2014. For all ankle sprains, we compared the number of visits, length of time between the first and last visit, number of services, and types of services between males and females using means, standard deviations, and independent-samples t-tests. Results Over the 3 year period, 3213 ankle sprains received treatment: 1910 (59%) in males and 1303 (41%) in females. The average number of ATR visits and treatments per injury was not different between males (6.31, SD=8.51; 22.8, SD=36.7) and females (6.04, SD=7.50; 21.4, SD=27.4; p=0.34 and p=0.20, respectively). The average length of time between the first and last treatment was 2.5 days longer among females (28.8, SD=28.2) compared to males (26.3, SD=25.7; p=0.02). However, the average number of modality treatments per ankle sprain was larger in males (2.74, SD=4.64) than females (2.31, SD=3.59; p=0.003), and the average number of taping treatments per ankle sprain was larger in males (2.94, SD=2.69) than females (2.49, SD=2.28; p=0.01). Conclusion While the number of ATR visits and treatments for ankle sprains did not differ by sex, the treatment course length and types of treatments, but the clinical significance is unknown. Significance/Contribution to Injury and Violence Prevention Science Women are at increased risk of sustaining an initial ankle sprain. Further, chronic ankle instability (CAI), a condition that significantly burdens many athletes throughout life, is more prevalent in females. Proper management may reduce the risk of recurrent sprains and CAI. Further examination is needed to determine whether males and females are receiving equal quality of care.