National Collegiate Athletic Association Injury Surveillance System Research Articles

Sports Injury Epidemiology: Foundation of Evidence of, by, and for Athletic Trainers.

Sports Injury Epidemiology: Foundation of Evidence of, by, and for Athletic Trainers.

Epidemiology of Severe Foot Injuries in US Collegiate Athletes.

Background:The effects of foot injuries on collegiate athletes in the United States are of interest because of the short 5-year eligibility period in the National Collegiate Athletic Association (NCAA).Purpose:To discuss the epidemiology of severe NCAA foot injuries sustained over 10 years in 25 sports.Study Design:Descriptive epidemiology study.Methods:We utilized the NCAA Injury Surveillance System, which prospectively collects deidentified injury data for collegiate athletes. Severe injuries were classified as season- or career-ending injuries, injuries with >30-day time loss, or injuries requiring operative treatment. Injury rates (IRs) were analyzed per 100,000 athlete-exposures.Results:Of 3607 total foot injuries, 18.71% (n = 675) were classified as severe, with an IR of 5.73 per 100,000 athletic-exposures. For all severe injuries, the operative rate was 24.3%, the season-ending rate 37.0%, and the career-ending rate 4.4%. The proportion of recurrent injuries was 13.9%. Men’s sports with the highest severe foot IRs were basketball (IR = 10.71), indoor track (IR = 7.16), and football (IR = 7.08). Women’s sports with the highest severe foot IRs were cross-country (IR = 17.15), gymnastics (IR = 14.76), and outdoor track (IR = 14.65). Among all severe foot injuries, the most common was a fifth metatarsal fracture. The highest contact/noncontact injury ratios were phalangeal fracture, turf toe, and Lisfranc injury. The severe injuries with the highest operative rates were Lisfranc injuries, fifth metatarsal fractures, and midfoot fractures. The severe injuries associated with the highest season-ending IRs were Lisfranc injury, midfoot fracture, and general metatarsal fractures. Severe flexor/extensor injuries had the highest career-ending IRs, followed by turf toe. Severe injuries with the highest median time loss were sesamoidal fractures, calcaneal fractures, and plantar fascial injuries.Conclusion:Of all collegiate foot injuries sustained over a 10-year period, 18.7% were characterized as severe, and 24.3% of severe injuries required surgery. Basketball was the men’s sport with the highest severe IR, and cross-country was the women’s sport with the highest severe IR. Overall, female athletes experienced slightly higher severe foot IRs as compared with male athletes.

Epidemiology of Anterior Cruciate Ligament Injury on Natural Grass Versus Artificial Turf in Soccer: 10-Year Data From the National Collegiate Athletic Association Injury Surveillance System.

Background:Anterior cruciate ligament (ACL) injury is prevalent among National Collegiate Athletic Association (NCAA) soccer players. Controversy remains regarding the effect of the surface type on the rate of ACL injury in soccer players, considering differences in sex, type of athletic exposure, and level of competition.Hypothesis:Natural grass surfaces would be associated with decreased ACL injury rate in NCAA soccer players. Sex, type of athletic exposure (match vs practice), and level of competition (Division I-III) would affect the relationship between playing surface and ACL injury rates.Study Design:Cohort study; Level of evidence, 3.Methods:Using the NCAA Injury Surveillance System (ISS) database, we calculated the incidence rate of ACL injury in men and women from 2004-2005 through 2013-2014 seasons. The incidence was normalized against athletic exposure (AE). Additional data collected were sex, athletic activity at time of injury (match vs practice), and level of competition (NCAA division) to stratify the analysis. Statistical comparisons were made by calculating incidence rate ratios (IRR). Statistical significance was set at an alpha of .05.Results:There were 30,831,779 weighted AEs during the study period. The overall injury rate was 1.12 ACL injuries per 10,000 AEs (95% CI, 1.08-1.16). Women comprised 57% of the match data (10,261 games) and 55% of practice data (26,664 practices). The overall injury rate was significantly higher on natural grass (1.16/10,000 AEs; 95% CI, 1.12-1.20) compared with artificial turf (0.92/10,000 AEs [95% CI, 0.84-1.01]; IRR, 1.26 [95% CI, 1.14-1.38]) (P < .0001). This relationship was demonstrated consistently across all subanalyses, including stratification by NCAA division and sex. The injury rate on natural grass (0.52/10,000 AEs; 95% CI, 1.11-1.26) was significantly greater than the injury incidence during practice on artificial turf (0.06/10,000 AEs; 95% CI, 0.043-0.096). Players were 8.67 times more likely to sustain an ACL injury during practice on natural grass compared with practice on artificial turf (95% CI, 5.43-12.13; P < .0001). No significant difference was found in injury rates between matches played on grass versus turf (IRR, 0.93; 95% CI, 0.84-1.03; P = .15).Conclusion:NCAA soccer players who practice on natural grass have increased risk of ACL injury compared with the risk of those practicing on an artificial surface, regardless of sex or NCAA division of play. No difference in risk of ACL injury between playing surfaces was detected during matches. Further research is necessary to examine the effect of multiple factors when evaluating the effect of the surface type on the risk of ACL injury in soccer players.

A Decade of Hip Injuries in National Collegiate Athletic Association Football Players: An Epidemiologic Study Using National Collegiate Athletic Association Surveillance Data.

The complex, high-energy nature of football puts players at risk for hip injuries. To analyze National Collegiate Athletic Association (NCAA) Injury Surveillance Program data for men's football hip injuries from 2004-2005 through 2013-2014. Descriptive epidemiologic study. National Collegiate Athletic Association football teams. Data on collegiate football players was provided by the NCAA Injury Surveillance System from 2004-2005 through 2013-2014. The incidence, risk factors, rates, and distribution of hip injuries over the 10-year period from 2004-2005 through 2013-2014 were determined. Rates and distribution of injuries were analyzed by injury type, time loss, event type, time of season, recurrence, mechanism of injury, player position, and if surgery was required. Injury rate ratios were calculated to compare rates between event types and by time of season. A total of 1618 hip injuries occurred during 3 121 380 athlete-exposures (AEs), resulting in an overall hip injury rate of 5.18 per 10 000 AEs. Adductor strains (38.63%) were the most common type, followed by hip-flexor strains (28.55%) and hip contusions (18.23%). Players were 3.56 (95% confidence interval [CI] = 3.19, 3.98) times more likely to sustain a hip injury during competitions compared with practices. They were 2.37 (95% CI = 2.15, 2.62) and 3.56 (95% CI = 2.49, 5.08) times more likely to sustain a hip injury during the preseason than in-season or the postseason, respectively. During the 10-year period, NCAA football players sustained higher rates of hip injuries during competitions and the preseason. The majority were noncontact injuries, resulted in time loss of less than 6 days, and did not require surgery. The injuries varied with player position and occurred most often to defensive backs. Muscle strains were the most frequent group of hip injuries, while adductor strains, hip-flexor strains, and hip contusions were the most common injury types.

Incidence of Knee Injuries on Artificial Turf Versus Natural Grass in National Collegiate Athletic Association American Football: 2004-2005 Through 2013-2014 Seasons

Background: The use of artificial turf in American football continues to grow in popularity, and the effect of these playing surfaces on athletic injuries remains controversial. Knee injuries account for a significant portion of injuries in the National Collegiate Athletic Association (NCAA) football league; however, the effect of artificial surfaces on knee injuries remains ill-defined. Hypothesis: There is no difference in the rate or mechanism of knee ligament and meniscal injuries during NCAA football events on natural grass and artificial turf playing surfaces. Study Design: Descriptive epidemiology study. Methods: The NCAA Injury Surveillance System Men’s Football Injury and Exposure Data Sets for the 2004-2005 through 2013-2014 seasons were analyzed to determine the incidence of anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), medial meniscus, and lateral meniscal tear injuries. Injury rates were calculated per 10,000 athlete exposures, and rate ratios (RRs) were used to compare injury rates during practices and competitions on natural grass and artificial turf in NCAA football as a whole and by competition level (Divisions I, Divisions II and III). Mechanisms of injury were calculated for each injury on natural grass and artificial turf surfaces. Results: A total of 3,009,205 athlete exposures and 2460 knee injuries were reported from 2004 to 2014: 1389 MCL, 522 ACL, 269 lateral meniscal, 164 medial meniscal, and 116 PCL. Athletes experienced all knee injuries at a significantly higher rate when participating in competitions as compared with practices. Athletes participating in competitions on artificial turf experienced PCL injuries at 2.94 times the rate as those playing on grass (RR = 2.94; 95% CI, 1.61-5.68). When stratified by competition level, Division I athletes participating in competitions on artificial turf experienced PCL injuries at 2.99 times the rate as those playing on grass (RR = 2.99; 95% CI, 1.39-6.99), and athletes in lower NCAA divisions (II and III) experienced ACL injuries at 1.63 times the rate (RR = 1.63; 95% CI, 1.10-2.45) and PCL injuries at 3.13 times the rate (RR = 3.13; 95% CI, 1.14-10.69) on artificial turf as compared with grass. There was no statistically significant difference in the rate of MCL, medial meniscal, or lateral meniscal injuries on artificial turf versus grass when stratified by event type or level of NCAA competition. No difference was found in the mechanisms of knee injuries on natural grass and artificial turf. Conclusion: Artificial turf is an important risk factor for specific knee ligament injuries in NCAA football. Injury rates for PCL tears were significantly increased during competitions played on artificial turf as compared with natural grass. Lower NCAA divisions (II and III) also showed higher rates of ACL injuries during competitions on artificial turf versus natural grass.

Multifactorial examination of sex-differences in head injuries and concussions among collegiate soccer players: NCAA ISS, 2004\u20132009

BackgroundWhile head injuries and concussions are major concerns among soccer players, the multifactorial nature of head injury observations in this group remains relatively undefined. We aim to extend previous analyses and examine sex-differences in the incidence of head injuries, odds of head injuries within an injured sample, and severity of head injuries, among collegiate soccer players between 2004 and 2009.MethodsData collected within the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) between the years of 2004 and 2009, were analyzed in this study. Unadjusted rate ratios (RR), compared incidence rates between categories of sex, injury mechanism, setting and competition level. We also examined sex-differences in head injury incidence rates, across categories of the other covariates. Multivariable logistic regression and negative binomial regression modeling tested the relation between sex and head injury corollaries, while controlling for contact, setting, and competition level.ResultsBetween 2004 and 2009, head injuries accounted for approximately 11% of all soccer-related injuries reported within the NCAA-ISS. The rate of head injuries among women was higher than among men (RR = 1.23, 95% CI = [1.08, 1.41]). The rate of head injuries due to player-to-player contact was comparable between women and men (RR = 0.95, 95% CI = [0.81, 1.11]). Whereas, the rate of injury due to contact with apparatus (ball/goal) was nearly 2.5 times higher (RR = 2.46, 95% CI = [1.76, 3.44]) and the rate due to contact with a playing surface was over two times higher (RR = 2.29, 95% CI = [1.34, 3.91]) in women than in men. In our multifactorial models, we also observed that the association between sex and head injury corollaries varied by injury mechanism.ConclusionsSex-differences in the incidence, odds (given an injury), and severity (concussion diagnosis, time-loss) of head injuries varied by injury mechanism (player-to-player contact vs. all other mechanisms) in this sample.

Sex Differences In Head Injuries Among Collegiate Soccer Players

Some of the highest rates of head injuries and concussion among all contact/collision sports are observed in soccer; yet, the multifactorial determinants of head injuries among players remain relatively undefined. PURPOSE: To examine sex-differences in the rate and the severity (lost days of participation, resultant concussions) of head injuries among collegiate soccer players between 2004 and 2009, while controlling for several covariables previously linked to injury occurrence. METHODS: Data from the National Collegiate Athletic Association Injury Surveillance System (NCAA-ISS) were used to calculate injury incidence density (ID) per 1000 athletic exposures (AE). The rate ratio (RR), along with the 95% Wald confidence interval (CI), compared ID among female, relative to male soccer players. Multivariable logistic regression and multivariable negative binomial regression modeling then tested the relation between sex and head injury incidence and severity while controlling for contact, setting, and competition level. RESULTS: Between 2004 and 2009, the sex-specific rate of soccer-related head injuries was 0.87 per 1000 AEs in women and 0.71 per 1000 AEs in men (RR = 1.23, 95% CI = [1.08, 1.41]). The rate of head injuries due to player-to-player contact was comparable between women and men (RR=0.95, 95% CI=[0.81, 1.11]); however, the rate of injury due to contact with apparatus was nearly 2 ½ -fold higher (RR=2.46, 95% CI = [1.76, 3.44]) and the rate due to contact with a playing surface was over two-fold higher (RR=2.29, 95% CI = [1.34, 3.91]) in women than in men. We also observed a significant joint effect between sex and contact in our regression models, with a particularly notable antagonistic interaction observed while modeling head injuries. CONCLUSION: Among female players, head contact with a ball, a goal post, or the playing surface may be especially deleterious compared with head contact with another player.

Audiovestibular symptoms as predictors of prolonged sports-related concussion among NCAA athletes.

We looked to determine the rates of audiovestibular symptoms following sports-related concussions among collegiate athletes. Further, we assessed the correlation between these symptoms and the time to return to participation in athletic activity. Retrospective analysis of the National Collegiate Athletic Association Injury Surveillance System (NCAA-ISS). The NCAA-ISS was queried from 2009 through 2014 for seven men's sports and eight women's sports across divisions 1, 2, and 3. Injuries resulting in concussions were analyzed for audiovestibular symptoms, duration of symptoms, and return to participation times. From 2009 to 2014, there were 1,647 recorded sports-related concussions, with athletes reporting dizziness (68.2%), imbalance (35.8%), disorientation (31.4%), noise sensitivity (29.9%), and tinnitus (8.5%). Concussion symptoms resolved within 1 day (17.1%), within 2 to 7 days (50.0%), within 8 to 30 days (25.9%), or persisted over 1 month (7.0%). Return to participation occurred within 1 week (38.3%), within 1 month (53.0%), or over 1 month (8.7%). Using Mann-Whitney U testing, overall symptom duration and return to competition time were significantly increased when any of these symptoms were present (P < 0.05). Duration of concussion symptom correlated with dizziness (P = 0.043) and noise sensitivity (P = 0.000), whereas return to participation times correlated with imbalance (P = 0.011) and noise sensitivity (P = 0.000). Dizziness and imbalance (odds ratio: 4.15, confidence interval: 3.20-5.38, P < 0.001) were the two symptoms with the strongest association. Audiovestibular symptoms are common complaints among collegiate athletes sustaining concussions. Dizziness and noise sensitivity correlated with the duration of concussive symptoms, whereas imbalance and noise sensitivity was correlated with prolonged return to competition time. 4. Laryngoscope, 127:2850-2853, 2017.

Maxillofacial injuries among National Collegiate Athletic Association athletes: 2004-2014

Participation in National Collegiate Athletic Association (NCAA) sports increases annually, yet the risk of maxillofacial injuries among these athletes is unknown. We report the incidence and trends in maxillofacial injuries among NCAA athletes. Retrospective study of the NCAA Injury Surveillance System (ISS) representing athletes from seven men's and eight women's sports across Divisions 1, 2, and 3. Incidence of maxillofacial injuries by sport, gender, anatomic location, and injuries requiring surgery were measured. Athlete exposure data from 2004 to 2005 through 2013 to 2014 were analyzed, along with maxillofacial injuries recorded in the NCAA-ISS. There were 2,017 injuries recorded, which projects to 41,204 injuries from 202,087,229 athlete events, or 2.04 injuries per 10,000 athlete events (95% confidence interval [CI], 1.68 to 2.40). Women had higher injury rates, 2.06 versus 2.03 (P = 0.016 [95% CI 0.22 to 2.09]). Highest rates were noted in men's wrestling 7.02 (95% CI, 2.84 to 11.19) and men's basketball 4.80 (95% CI, 3.57 to 6.02), and were lowest in women's ice hockey 0.61 (95% CI, 0.17 to 1.06) and women's volleyball 0.43 (95% CI, 0.20 to 0.66). No gender differences in fractures or need for surgery, but men sustained more operative fractures, 27.85% versus 17.04% (P = 0.035 [95% CI, 0.79 to 20.82]). Men's football, women's ice hockey, women's volleyball, and women's gymnastics had consistently low fracture rates. Maxillofacial injuries represent approximately 3.4% of all injuries sustained by NCAA athletes. Women had a higher injury rate, whereas men had a higher rate of operative facial fractures. Awareness and improved facial protection, especially among noncontact sports, will be crucial in reducing the incidence of these injuries. 4. Laryngoscope, 127:1296-1301, 2017.

Time Trends in Incidence and Severity of Injury Among Collegiate Soccer Players in the United States

Background: A number of sociocultural and environmental changes have occurred over the past several decades that may affect the risk of injury among young athletes playing soccer. Purpose: To identify trends in injury incidence and severity between 2 time periods (1990-1996 and 2004-2009) in both male and female National Collegiate Athletic Association (NCAA) soccer players in the United States. Design: Descriptive epidemiology study. Methods: Data were analyzed from the NCAA Injury Surveillance System. The rate ratio (RR), along with the 95% Wald CI, compared incidence density in 2004-2009 relative to that in 1990-1996. Results: Overall sex-pooled injury rates were significantly lower in the 2004-2009 cohort compared with the 1990-1996 cohort (RR = 0.88; 95% CI = 0.86-0.91), and this was true for almost every category of injury studied. We observed only 1 significant sex difference between the time periods with regard to noncontact injuries, as men experienced a significant increase in rate of noncontact injuries between 1990-1996 and 2004-2009 (RR = 1.09; 95% CI = 1.02-1.17), whereas women experienced a significant decrease (RR = 0.70; 95% CI = 0.67-0.75). Conclusion: These surveillance data show decreasing trends in collegiate soccer injuries. Whether these decreases are attributable to greater resources being allocated toward athlete health, injury management, or the safety of the playing environment cannot be determined. Given the prominence of soccer play in the United States, public health efforts should promote the use of this surveillance system to better inform and evaluate injury prevention practices and policies directed toward player safety.

Time Trends in Incidence and Severity of Injury among NCAA Soccer Players, 1990–1996 and 2004–2009

People under age 25 years comprise the largest cohort of soccer players in the U.S.; yet, the descriptive epidemiology of injury in this age group is limited. Moreover, there have been few analyses of injury occurrence across time that would allow investigators to monitor trends in response to changing practices and policies. PURPOSE: To identify trends in injury incidence and severity between two time periods (1990-1996 and 2004-2009) in NCAA soccer players. METHODS: Data were analyzed from the National Collegiate Athletic Association Injury Surveillance System (NCAA-ISS). As per data collection guidelines, injury incidence was defined as: 1) any injury event that occurred during participation in an intercollegiate game or practice; 2) that required medical attention; and 3) restricted participation or performance for >1 day beyond the event. To account for varying levels of playing exposure among the athletes we calculated Athlete-Exposure (AE), defined as a single athlete participating in a single practice or competition with any probability of injury. Incidence density then was calculated as the number of events per 1000 AE within each time period. The rate ratio (RR), along with the 95% confidence interval (CI), compared incidence density and severity in 2004-2009 relative to 1990-1996. RESULTS: Overall injury rates were significantly lower in the 2004-2009 cohort compared with the 1990-1996 cohort [RR=0.88 (95%CI=0.86, 0.91)] and this was true for almost every category of injury studied. The lower rates were especially noticeable for recurrent injuries [RR=0.62 (95%CI=0.57, 0.68)], short-term injuries [RR=0.69 (95%CI=0.67, 0.72)] and for injuries requiring surgery [RR=0.35 (95%CI=0.29, 0.41)]. There was also a significant reduction in injuries occurring during games, particularly during the second half [RR=0.69 (95%CI: 0.66, 0.73)]. In contrast, we observed a significant increase in rates of long-term (>7 days of lost time) injuries between the two time periods [RR=1.33 (95%CI=1.27, 1.40)]. CONCLUSIONS: Given the prominence of soccer play in the United States, public health efforts should promote the use of this surveillance system to better inform and evaluate injury prevention practices and policies directed toward player safety.

National collegiate athletic association injury surveillance system: review of methods for 2004-2005 through 2013-2014 data collection.

Since 1982, the National Collegiate Athletic Association has used the Injury Surveillance System (ISS) to collect injury and athlete-exposure data from a representative sample of collegiate institutions and sports. At the start of the 2004-2005 academic year, a Web-based ISS replaced the paper-based platform previously used for reporting injuries and exposures. To describe the methods of the Web-based National Collegiate Athletic Association ISS for data collection as implemented from the 2004-2005 to 2013-2014 academic years. The Web-based ISS monitored National Collegiate Athletic Association-sanctioned practices and competitions, the number of participating student-athletes, and time-loss injuries during the preseason, regular season, and postseason in 25 collegiate sports. Starting in the 2009-2010 academic year, non-time-loss injuries were also tracked. Efforts were made to better integrate ISS data collection into the workflow of collegiate athletic trainers. Data for the 2004-2005 to 2013-2014 academic years are available to researchers through a standardized application process available at the Datalys Center Web site. As of February 2014, more than 1 dozen data sets have been provided to researchers. The Datalys Center encourages applications for access to the data.

Epidemiology of Syndesmosis Injuries in Intercollegiate Football

To describe the incidence and risk factors for high ankle sprains (ie, syndesmosis injuries) among National Collegiate Athletic Association (NCAA) football players. Descriptive epidemiologic study. Data were examined from the NCAA's Injury Surveillance System (ISS) for 5 football seasons (from 2004-2005 to 2008-2009). All NCAA men's football programs participating in the ISS. No additional risk factors were introduced as a result of this analysis. For partial and complete syndesmosis injuries, outcome measures included incidence, time lost from participation, and requirement for surgical repair. The overall incidence of high ankle sprains in NCAA football players was 0.24 per 1000 athlete exposures, accounting for 24.6% of all ankle sprains. Athletes were nearly 14 times more likely to sustain the injury during games compared with practice; complete syndesmosis injuries resulted in significantly greater time lost compared with partial injuries (31.3 vs 15.8 days). Less than 3% of syndesmosis injuries required surgical intervention. There was a significantly higher injury incidence on artificial surfaces compared with natural grass. The majority of injuries (75.2%) occurred during contact with another player. Our data suggest a significantly higher incidence of syndesmosis injuries during games, during running plays, and to running backs and interior defensive linemen. The wide range in time lost from participation for complete syndesmosis injuries underscores the need for improved understanding of injury mechanism and classification of injury severity such that prevention, safe return to play protocols, and outcomes can be further improved.

Acromioclavicular Joint Injuries in National Collegiate Athletic Association Football

Background: Injuries to the shoulder are common in collegiate football, and injuries to the acromioclavicular (AC) joint have previously accounted for up to 41% of all shoulder injuries. Purpose: To determine the incidence and epidemiology of injury to the AC joint in National Collegiate Athletic Association (NCAA) football athletes. Study Design: Descriptive epidemiology study. Methods: The NCAA Injury Surveillance System (ISS) men’s football database was reviewed from the 2004-2009 playing seasons. The exposure data set from the same years was reviewed for the purposes of computing rates of injury per athlete exposure (AE). The injury rate (number of injuries divided by number of AEs) was computed per 10,000 AEs for competition and practice exposures. Ninety-five percent confidence intervals (95% CIs) for the incidence rates were calculated using assumptions of a Poisson distribution. Results: According to the estimates made by the NCAA ISS, a total of 748 injuries to the AC joint occurred in NCAA football players during 2,222,155 AEs, accounting for 4.49% of all injuries sustained during this 5-year surveillance period. The overall rate of injury was 3.34 per 10,000 AEs (95% CI, 3.10-3.59). Players were 11.68 (95% CI, 10.11-13.49) times more likely to sustain an injury in games than practices. Partial sprains (types I or II) accounted for 96.4% of injuries, while complete sprains (≥type III) accounted for the remaining 3.6%. The average amount of time lost per injury was 11.61 days. Complete sprains resulted in a mean time loss of 31.9 days (95% CI, 24.4-39.6) while partial injuries resulted in 11.0 days lost (95% CI, 9.6-12.3). Overall, 2.41% of injuries underwent surgical intervention, with 22.2% of complete sprains and 1.7% of partial injuries resulting in surgery. Complete sprains of the AC joint were 13.5 (95% CI, 4.63-35.26) times more likely to result in surgical intervention than partial sprains. The majority of injuries (71.93%) resulted from contact with another player and 47.09% occurred while tackling or being tackled. Of all injuries, 47.63% occurred during offensive plays, while defense accounted for 20.77%. Conclusion: AC joint injuries in NCAA football players are predominantly low-grade sprains, leading to approximately 12 days of lost competition. The few severe sprains that occurred often resulted in surgery or required approximately 5 weeks of rehabilitation.

Incidence and Risk Factors for Injuries to the Anterior Cruciate Ligament in National Collegiate Athletic Association Football

Background: Injuries to the anterior cruciate ligament (ACL) are common in athletic populations, particularly in athletes participating in football, soccer, and skiing. Purpose: The purpose of this study was to analyze the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) men’s football ACL injury database from the playing seasons of 2004-2005 through 2008-2009 to determine the incidence and epidemiology of complete injury to the ACL in NCAA football athletes. Study Design: Descriptive epidemiology study. Methods: The NCAA ISS men’s football database was reviewed from the 2004-2005 through 2008-2009 seasons using the specific injury code, “Anterior cruciate ligament (ACL) complete tear.” The injury rate was computed for competition and practice exposures. Ninety-five percent confidence intervals (CIs) for the incident rates were calculated using assumptions of a Poisson distribution. Pairwise, 2-sample tests of equality of proportions with a continuity correction were used to estimate the associations of risk factors such as event type, playing surface, season segment, and football subdivision. Descriptive data were also described. Results: The ACL injury rate during games (8.06 per 10,000 athlete-exposures [AEs] 95% CI, 6.80-9.42) was significantly greater than the rate during practice (0.8 per 10,000 AEs 95% CI, 0.68-0.93). Players were 10.09 (95% CI, 8.08-12.59) times more likely to sustain an ACL injury in competition when compared with practices. When practice exposures were analyzed separately, the injury rate was significantly greater during scrimmages (3.99 per 10,000 AEs 95% CI, 2.29-5.94) compared with regular practices (0.83 per 10,000 AEs 95% CI, 0.69-0.97) and walk-throughs (0 per 10,000 AEs 95% CI, 0-0.14). There was an incidence rate of 1.73 ACL injuries per 10,000 AEs (95% CI, 1.47-2.0) on artificial playing surfaces compared with a rate of 1.24 per 10,000 AEs (95% CI, 1.05-1.45) on natural grass. The rate of ACL injury on artificial surfaces is 1.39 (95% CI, 1.11-1.73) times higher than the injury rate on grass surfaces. Conclusion: Between 2004 and 2009, NCAA football players experienced a greater number of ACL injuries in games compared with practices, in scrimmages compared with regular practices, and when playing on artificial turf surfaces. This latter finding will need to be confirmed by additional studies.

Epidemiological Considerations of Concussions Among Intercollegiate Athletes

The purpose of this study was to examine epidemiological trends of concussions among 15 different intercollegiate sports during the 1997-1998, 1998-1999, and 1999-2000 seasons. Data were collected using the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS). For the 15 sports studied during the 3 academic years, the NCAA ISS documented 3,535 team-seasons, 40,547 reportable injuries, 5,566,924 practice athlete exposures (AEs), and 1,090,298 game AEs. Concussions accounted for 6.2% of all reported injuries during this 3-year study. Of all the reported injuries, women lacrosse players (13.9%) reported the highest percentage of suffering a concussion during a game followed by women's soccer (11.4%), men's ice hockey (10.3%), men's lacrosse (10.1%), football (8.8%), women's basketball, (8.5%), field hockey (7.2%), men's soccer (7.0%), wrestling (6.6%), men's basketball (5.0%), baseball (4.2%), and women's volleyball (4.1%). Female athletes from all 7 sports were found to be at a lower risk for suffering concussions during practice sessions than the 8 male sports. However, female athletes were found to be at a greater risk for suffering concussions during games compared to male athletes. Injury trends over the 3-year period indicate concussions continue to be on the rise for athletes participating in collegiate football, men's soccer, and women's and men's basketball.