Epidemiology of Knee Sprains in Youth, High School, and Collegiate American Football Players

Context: Variations in knee-sprain incidence among competition levels are unclear but may help inform prevention strategies in American football players. Objective: To describe the epidemiology of knee sprains in youth, high school, and collegiate football players. Design: Descriptive epidemiology study. Setting: Injury and athlete-exposure (AE) data were collected from 3 injury-surveillance programs at the youth, high school, and collegiate competition levels. Patients or Other Participants: Data from 310 youth, 184 high school, and 71 collegiate football team-seasons were collected during the 2012 through 2014 seasons. Main Outcome Measure(s): Knee-sprain rates and risks were calculated for each competition level. Injury rate ratios (IRRs) and risk ratios (RRs) compared knee-sprain rates by competition level. Injury proportion ratios (IPRs) compared differences in surgery needs, recurrence, injury mechanism, and injury activity by competition level. Results: Knee-sprain rates in youth, high school, and collegiate football were 0.16/1000 AEs, 0.25/1000 AEs, and 0.69/1000 AEs, respectively. Knee-sprain rates increased as the competition level increased (high school versus youth: IRR = 1.60; 95% confidence interval [CI] = 1.12, 2.30; collegiate versus high school: IRR = 2.73; 95% CI = 2.38, 3.96). Knee-sprain risk was highest in collegiate (4.3%), followed by high school (2.0%) and youth (0.5%) athletes. Knee-sprain risk increased as the competition level increased (high school versus youth: RR = 3.73; 95% CI = 2.60, 5.34; collegiate versus high school: RR = 2.14; 95% CI = 1.83, 2.51). Collegiate football had the lowest proportion of knee sprains that were noncontact injuries (collegiate versus youth: IPR = 0.54; 95% CI = 0.31, 0.95; collegiate versus high school: IPR = 0.59; 95% CI = 0.44, 0.79) and the lowest proportion that occurred while being tackled (collegiate versus youth: IPR = 0.44; 95% CI = 0.26, 0.76; collegiate versus high school: IPR = 0.71; 95% CI = 0.51, 0.98). Conclusions: Knee-sprain incidence was highest in collegiate football. However, level-specific variations in the distributions of knee sprains by injury activity may highlight the need to develop level-specific policies and prevention strategies that ensure safe sports play.

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Incidence, Severity, and Time Loss Associated With Collegiate Football Fractures, 2004-2005 to 2013-2014

The American Journal of Sports Medicine ◽

10.1177/0363546517749914 ◽

2018 ◽

Vol 46 (4) ◽

pp. 987-994 ◽

Cited By ~ 3

Author(s):

Mark A. Cairns ◽

Eddie K. Hasty ◽

Mackenzie M. Herzog ◽

Robert F. Ostrum ◽

Zachary Y. Kerr

Keyword(s):

National Collegiate Athletic Association ◽

Injury Rate ◽

Surveillance Program ◽

Football Players ◽

Descriptive Epidemiology ◽

Prevention Strategies ◽

Time Loss ◽

Inherent Risk ◽

Rate Ratios ◽

Collegiate Football

Background: The inherent risk of any time loss from physical injury in football has been extensively discussed, with many such injuries having a profound effect on the lives of National Collegiate Athletic Association (NCAA) football players. However, the incidence of fractures in collegiate football has not been well established. Purpose: To examine the epidemiology of fractures in NCAA football. Study Design: Descriptive epidemiology study. Methods: Fracture data reported in college football during the 2004-2005 to 2013-2014 academic years were analyzed from the NCAA Injury Surveillance Program (NCAA-ISP). Fracture rates per 1000 athlete-exposures, surgery and time loss distributions, injury rate ratios, injury proportion ratios (IPRs), and 95% CIs were reported. Results: Overall, 986 fractures were reported. The rate of competition fractures was larger than the rate of practice fractures (1.80 vs 0.17 per 1000 athlete-exposures; injury rate ratio = 10.56; 95% CI, 9.32-11.96). Fractures of the hand/fingers represented 34.6% of all injuries, while fibula fractures (17.2%) were also common. A majority (62.5%) of all fractures resulted in time loss >21 days. Altogether, 34.4% of all fractures required surgery, and 6.3% were recurrent. The proportion of fractures resulting in time loss >21 days was higher for fractures requiring surgery than fractures not requiring surgery (85.0% vs 50.7%; IPR = 1.68; 95% CI, 1.53-1.83). The proportion of recurrent and nonrecurrent fractures requiring surgery did not differ (35.5% vs 34.3%; IPR = 1.03; 95% CI, 0.73-1.46); however, recurrent fractures were more likely to require surgery than nonrecurrent fractures when restricted to the hand/fingers (66.7% vs 27.2%; IPR = 2.45; 95% CI, 1.36-4.44). Conclusion: Fractures in collegiate football were sustained at a higher rate in competition than practice and frequently required extended time lost from participation, particularly among those requiring surgery. Prevention strategies are warranted to reduce incidence and severity of fractures.

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Age of First Exposure to American Football and Behavioral, Cognitive, Psychological, and Physical Outcomes in High School and Collegiate Football Players

Sports Health A Multidisciplinary Approach ◽

10.1177/1941738119849076 ◽

2019 ◽

Vol 11 (4) ◽

pp. 332-342 ◽

Cited By ~ 12

Author(s):

Benjamin L. Brett ◽

Daniel L. Huber ◽

Alexa Wild ◽

Lindsay D. Nelson ◽

Michael A. McCrea

Keyword(s):

High School ◽

Clinical Outcome ◽

Outcome Measures ◽

Collegiate Athletes ◽

American Football ◽

Outcome Variable ◽

Football Players ◽

Level Of Evidence ◽

Intermediate Outcomes ◽

Collegiate Football

Background: Although some studies have observed a relationship between age of first exposure (AFE) to American football and long-term outcomes, recent findings in collegiate athletes did not observe a relationship between AFE and more intermediate outcomes at early adulthood. This, however, requires independent replication. Hypothesis: There will be no association between AFE to football and behavioral, cognitive, emotional/psychological, and physical functioning in high school and collegiate athletes. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: Active high school and collegiate football players (N = 1802) underwent a comprehensive preseason evaluation on several clinical outcome measures. Demographic and health variables that significantly differed across AFE groups were identified as potential covariates. General linear models (GLMs) with AFE as the independent variable were performed for each clinical outcome variable. Similar GLMs that included identified covariates, with AFE as the predictor, were subsequently performed for each clinical outcome variable. Results: After controlling for covariates of age, concussion history, race, and a diagnosis of ADHD, earlier AFE (<12 vs ≥12 years) did not significantly predict poorer performance on any clinical outcome measures (all P > 0.05). A single statistically significant association between AFE group and somatization score was recorded, with AFE <12 years exhibiting lower levels of somatization. Conclusion: In a large cohort of active high school and collegiate football student-athletes, AFE before the age of 12 years was not associated with worse behavioral, cognitive, psychological, and physical (oculomotor functioning and postural stability) outcomes. Clinical Relevance The current findings suggest that timing of onset of football exposure does not result in poorer functioning in adolescence and young adults and may contribute to resilience through decreased levels of physically related psychological distress.

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Injuries in a Japanese Division I Collegiate American Football Team: A 3-Season Prospective Study

Journal of Athletic Training ◽

10.4085/1062-6050-48.4.15 ◽

2013 ◽

Vol 48 (6) ◽

pp. 818-825 ◽

Cited By ~ 5

Author(s):

Junta Iguchi ◽

Yosuke Yamada ◽

Misaka Kimura ◽

Yoshihiko Fujisawa ◽

Tatsuya Hojo ◽

...

Keyword(s):

United States ◽

Prospective Study ◽

Injury Rate ◽

The United States ◽

American Football ◽

Division I ◽

Data Set ◽

Injury Rates ◽

Football Team ◽

Collegiate Football

Context: Previous research on American football injuries in Japan has focused on incidence proportion in terms of the number of injuries divided by the number of players. This is the first study to examine injury rates over several seasons. Objective: To conduct a prospective study of injuries in a Japanese Division I collegiate American football team over the 2007 through 2009 seasons. Design: Cohort study. Setting: Collegiate football team at Doshisha University, Kyoto, Japan. Patients or Other Participants: All 289 athletes who played on the collegiate Division I football team during the 2007 through 2009 seasons. Main Outcome Measure(s): A certified athletic trainer kept a daily record of all practice and game injuries. Injury rates were calculated according to season, injury type, body part, severity, and mechanism. Injuries were also analyzed according to position of player, school year, and playing experience. Results: The game injury rate (GIR; 32.7 injuries/1000 athlete-exposures) was higher than the practice injury rate (PIR; 10.9 injuries/1000 athlete-exposures) over the 3 seasons (P < .05). The PIR was higher among Japanese players than the comparable United States collegiate football injury rates (5.8–7.0 injuries/1000 athlete-exposures). Ankle and foot injuries occurred more frequently during games, whereas thigh and gluteal injuries occurred more frequently during practices. Conclusions: Our data show differences between games and practices in terms of injury rates, body parts injured, and positions of players injured. The high PIR in Japan may be due to the increased contact during practices and length of practices compared with the United States. Further research involving multiple teams is recommended to validate the trends noted in this study. The expanded data set could assist in the development of safety regulations and preventive interventions for Japanese football.

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A - 02 The Epidemiology of Concussion in Middle School Football

Archives of Clinical Neuropsychology ◽

10.1093/arclin/acab035.02 ◽

2021 ◽

Vol 36 (4) ◽

pp. 642-642

Author(s):

Blackstone A ◽

Kelshaw P ◽

Hacherl S ◽

Erdman N ◽

Lincoln A ◽

...

Keyword(s):

High School ◽

Middle School ◽

Return To Sport ◽

Injury Rate ◽

American Football ◽

High School Football ◽

Certified Athletic Trainers ◽

Older Athletes ◽

Public Middle School ◽

Rate Ratios

Abstract Objective Middle school is often the first exposure to American football for many children. However, research examining concussion in football has primarily focused on high school and older athletes. Therefore, we investigated the incidence of concussion and subsequent sport time loss (TL) in MS football. Methods Athlete exposure (AE) and injury rates (IR) were gathered by onsite Certified Athletic Trainers within public middle school for all events across the 2015/16–2019/20 school years. AE was defined as one athlete participating in one practice or game. TL was defined as the number of days between the injury and return to sport dates. Concussion rates per 1000AE with corresponding confidence intervals (CI) were calculated. Injury rate ratios (IRR) with 95% CIs were compared IR between practices and games. CIs excluding 1.0 were considered significant. Results 75 concussions (IR = 1.38/1000AE, 95% CI = 1.06–1.69) occurred across 54,544 AEs. The concussion rate was significantly higher in games (n = 31, IR = 3.51, 95%CI = 2.27–4.75) than practices (n = 44, IR = 0.96, 95%CI = 0.68–1.25; IRR = 3.65, 95%CI = 2.30–5.77). The mean sport TL was 16.50 ± 8.25 days. Conclusions We observed middle school football concussion rates (practices and games) and associated TL from sport to be consistent with prior youth and high school football research. However, the concussion rate for middle school games was more than 3 times that of practices. This is similar to prior middle school football findings, but less than reported in high school football. Continued research evaluating modifiable risk factors for concussion in middle school football games and practices is needed.

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The Epidemiology of Overuse Conditions in Youth Football and High School Football Players

Journal of Athletic Training ◽

10.4085/1062-6050-52.10.04 ◽

2017 ◽

Vol 52 (10) ◽

pp. 976-981

Author(s):

Kevin Morris ◽

Janet E. Simon ◽

Dustin R. Grooms ◽

Chad Starkey ◽

Thomas P. Dompier ◽

...

Keyword(s):

High School ◽

Epidemiologic Study ◽

Injury Rate ◽

Football Players ◽

Primary Concern ◽

High School Football ◽

Sport Training ◽

School Sports ◽

Youth Football ◽

Rate Ratios

Context: High-intensity sport training at the youth level has led to increased concern for overuse conditions. Few researchers have examined overuse conditions in youth sports.Objective: To examine the rates, risks, and distributions of overuse conditions between youth and high school football players.Design: Descriptive epidemiologic study.Setting: Youth and high school football teams.Patients or Other Participants: The Youth Football Safety Study (YFSS) investigated youth football athletes from age 5 to 14 years. The National Athletic Treatment, Injury and Outcomes Network (NATION) focused on high school football athletes 14 to 18 years old. The YFSS data consisted of 210 team-seasons, and the NATION data consisted of 138 team-seasons.Main Outcome Measure(s): Athletic trainers collected football injury and exposure data during the 2012 and 2013 seasons. Injury rates, risks, and distributions were calculated, with injury rate ratios, risk ratios, and injury proportion ratios with 95% confidence intervals (CIs) comparing youth and high school football players.Results: The YFSS reported 1488 injuries, of which 53 (3.6%) were overuse conditions. The NATION reported 12 013 injuries, of which 339 (2.8%) were overuse conditions. The overuse condition rate did not differ between high school and youth football (3.93 versus 3.72/10 000 athlete-exposures; injury rate ratio = 1.06; 95% CI = 0.79, 1.41). However, the 1-season risk of overuse condition was higher in high school than in youth football players (2.66% versus 1.05%; risk ratio = 2.53; 95% CI = 1.84, 3.47). Compared with high school football players, youth football players had greater proportions of overuse conditions that were nontime loss (ie, <24 hours participation-restriction time; 83.0% versus 67.0%; injury proportion ratio = 1.24; 95% CI = 1.07, 1.43) and affecting the lower extremity (92.5% versus 62.5%; injury proportion ratio = 1.48; 95% CI = 1.32, 1.65).Conclusions: Overuse conditions may not present a primary concern in youth and high school football players. However, differences existed between the 2 levels of competition. Although additional research on the incidence of overuse conditions across all youth and high school sports is needed, these findings may highlight the need for programming that is specific to competition level.

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Examining Play Counts and Measurements of Injury Incidence in Youth Football

Journal of Athletic Training ◽

10.4085/1062-6050-52.7.06 ◽

2017 ◽

Vol 52 (10) ◽

pp. 955-965 ◽

Cited By ~ 4

Author(s):

Zachary Y. Kerr ◽

Susan W. Yeargin ◽

Aristarque Djoko ◽

Sara L. Dalton ◽

Melissa M. Baker ◽

...

Keyword(s):

Outcome Measure ◽

Age Groups ◽

Injury Rate ◽

Football Players ◽

Injury Incidence ◽

Injury Rates ◽

Head Impacts ◽

Youth Football ◽

Rate Ratios ◽

Age Range

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.

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The Epidemiology of Injuries in Middle School Football, 2015-2017: The Advancing Healthcare Initiatives for Underserved Students Project

The American Journal of Sports Medicine ◽

10.1177/0363546518825361 ◽

2019 ◽

Vol 47 (4) ◽

pp. 933-941 ◽

Cited By ~ 4

Author(s):

Zachary Y. Kerr ◽

Nelson Cortes ◽

Jatin P. Ambegaonkar ◽

Amanda M. Caswell ◽

Matt Prebble ◽

...

Keyword(s):

Middle School ◽

Injury Prevention ◽

Injury Rate ◽

Surveillance Systems ◽

Injury Incidence ◽

Prevention Strategies ◽

Certified Athletic Trainers ◽

Injury Rates ◽

Underserved Students ◽

Rate Ratios

Background: Although data exist on injuries in youth football leagues, there are limited recent data on injury incidence in middle school football. Updated injury incidence estimates can help drive the development of injury prevention strategies. Purpose: Describe the epidemiology of injuries in middle school football during school years 2015-2016 to 2017-2018. Study Design: Descriptive epidemiology study. Methods: Data originated from 9 public middle schools in Virginia during school years 2015-2016 to 2017-2018. Certified athletic trainers collected injury and athlete-exposure (AE) data from school-sanctioned games and practices in boys’, football. Injury counts and rates per 1000 AEs were calculated. Injury rate ratios with 95% CIs compared rates between games and practices. Results: Overall, 664 middle school boys’, football injuries were reported, leading to an overall injury rate of 20.54 per 1000 AEs (95% CI, 18.98-22.11). The time loss injury rate (inclusive of injuries with participation restriction time ≥24 hours) was 9.28 per 1000 AEs (95% CI, 8.23-10.33). The injury rate was higher in competition than practice (36.19 vs 17.97 per 1000 AEs; injury rate ratio, 2.01; 95% CI, 1.69-2.40). Most injuries were to the head/face (competition, 20.6%; practice, 15.8%) and hand/wrist (competition, 18.8%; practice, 16.4%) and were diagnosed as contusions (competition, 30.9%; practice, 25.9%) and sprains (competition, 19.4%; practice, 12.6%). Competitions also had a large proportion of concussions (10.3%). Overall, 80.0% and 66.9% of injuries were due to contact in competition and practice, respectively; of these contact-related injuries, 62.1% and 41.6% were specifically player contact. Conclusion: Injury distributions parallel those found in previous research from middle school and other sport settings. Injury rates in middle school football were higher than those reported in previous findings in high school and college. However, caution must be taken when interpreting findings in relation to other surveillance systems with varying methodologies. Still, the findings highlight the need for injury prevention strategies within middle school football, particularly as related to contact-related mechanisms.

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Epidemiology of Cervical Muscle Strains in Collegiate and High School Football Athletes, 2011–2012 Through 2013–2014 Academic Years

Journal of Athletic Training ◽

10.4085/1062-6050-229-18 ◽

2019 ◽

Vol 54 (7) ◽

pp. 780-786

Author(s):

Katherine M. Lee ◽

Melissa C. Kay ◽

Kristen L. Kucera ◽

William E. Prentice ◽

Zachary Y. Kerr

Keyword(s):

High School ◽

Rate Ratio ◽

National Collegiate Athletic Association ◽

Injury Rate ◽

Adverse Outcomes ◽

Surveillance Program ◽

Football Players ◽

Surveillance Systems ◽

High School Football ◽

Cervical Muscle

Context Cervical muscle strains are an often-overlooked injury, with neck- and spine-related research typically focusing on spinal cord and vertebral injuries. Objective To examine the rates and distributions of cervical muscle strains in collegiate and high school football athletes. Design Descriptive epidemiology study. Setting Collegiate and high school football teams. Patients or Other Participants The National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) collected data from collegiate football athletes. The High School National Athletic Treatment, Injury and Outcomes Network (HS NATION) and High School Reporting Information Online (HS RIO) collected data from high school football athletes. Data from the 2011–2012 through 2013–2014 academic years were used. Main Outcome Measure(s) Athletic trainers collected injury and exposure data for football players. Injury counts, injury rates per 10 000 athlete-exposures (AEs), and injury rate ratios with 95% confidence intervals (CIs) were calculated. Results The NCAA-ISP reported 49 cervical muscle strains (rate = 0.96/10 000 AEs), of which 28 (57.1%) were TL (time loss; rate = 0.55/10 000 AEs). High School NATION reported 184 cervical muscle strains (rate = 1.66/10 000 AEs), of which 33 (17.9%) were TL injuries (rate = 0.30/10 000 AEs). The HS RIO, which collects only TL injuries, reported 120 TL cervical muscle strains (rate = 0.51/10 000 AEs). The overall injury rate was lower in the NCAA-ISP than in HS NATION (injury rate ratio = 0.58; 95% CI = 0.42, 0.79); when restricted to TL injuries, the overall injury rate was higher in the NCAA-ISP (injury rate ratio = 1.83; 95% CI = 1.11, 3.03). No differences were found when comparing TL injuries in HS RIO and the NCAA-ISP. Cervical muscle-strain rates were higher during competitions than during practices across all 3 surveillance systems for all injuries. Most cervical muscle strains were due to player contact (NCAA-ISP = 85.7%, HS NATION = 78.8%, HS RIO = 85.8%). Conclusions The incidence of cervical muscle strains in football players was low compared with other injuries. Nonetheless, identifying and implementing interventions, particularly those aimed at reducing unsafe player contact, are essential to further decrease the risk of injury and associated adverse outcomes.

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