The First Decade of Web-Based Sports Injury Surveillance: Descriptive Epidemiology of Injuries in US High School Boys' Lacrosse (2008-2009 Through 2013-2014) and National Collegiate Athletic Association Men's Lacrosse (2004-2005 Through 2013-2014)

Headgear use in girls' lacrosse-stakeholders not ready for change

Purpose

Mandating headgear for field players in girls' lacrosse to reduce head injuries, including concussion, has been heavily debated. However, research regarding the need and effectiveness of mandated headgear use in girls' lacrosse is still developing. Therefore, this qualitative study aimed to identify the need for and barriers to the development of mandated headgear use policies in girls' lacrosse in Ohio.

Methods

We conducted six virtual focus groups, three with concussion experts (clinicians and researchers) and three with girls' lacrosse stakeholders (high school players, parents, coaches, and officials). A focus group guide was developed to explore study participants' perceptions and opinions on concussion in girls' lacrosse, headgear use among players, and policies and policy development related to headgear use or a headgear mandate. We developed the codebook using an inductive and iterative approach based on focus group transcripts and used ATLAS.TI to code and analyze the transcript data.

Results

Concussion experts and stakeholders understood the potential consequences of concussion but did not perceive concussion as a pervasive problem in girls' lacrosse. The prevention of head and facial injuries was regarded as a potential benefit of headgear use. However, stakeholders expressed that the myriad of arguments discussed opposing mandated headgear use including increased aggressive play and/or targeting, concerns over changes in the game, and cost strongly outweighed the benefits. Finally, both concussion experts and stakeholders identified multiple organizations, including USA Lacrosse, who could act as facilitators and/or barriers to developing, enacting, and implementing headgear policies.

Conclusions

Concussion experts and stakeholders identified possible reasons for headgear use related to injury prevention but also identified several important barriers to the development of a headgear mandate for girls' lacrosse in Ohio.

Epidemiology of injuries in U.S. high school track and field throwing events from 2008 to 2019

BACKGROUND

Injury characteristics of high school track and field throwing athletes in the United States are not well studied. Understanding epidemiology of injuries is important to identify treatment and prevention strategies.

OBJECTIVE

To describe injury rates and patterns in U.S. high school track and field throwing events from a longitudinal national sports injury surveillance system.

DESIGN

Descriptive epidemiology study.

SETTING

Data were provided by the National High School Sports Related Injury Surveillance System, High School RIO (Reporting Information Online).

METHODS

Athletic trainers reported injury and exposure data through the High School RIO website on a weekly basis. An athlete exposure (AE) was defined as one athlete participating in one school-sanctioned practice or competition. Throwing events of discus, shot put, and javelin were analyzed in this study.

MAIN OUTCOME MEASURES

Injury rate, rate ratios (RR), injury proportion ratios (IPR).

PARTICIPANTS

U.S. high school athletes.

RESULTS

A total of 267 track and field throwing injuries occurred during 5,486,279 AEs. Overall, the rate of injuries in competition was higher than in practice (RR 1.35, 95% confidence interval [CI] 1.01-1.80). In practice, the rate of injuries was higher for girls than boys (RR 1.53, 95% CI 1.12-2.08). The most frequently injured body part was the shoulder (21.7%), followed by the ankle (16.5%) and knee (12.0%). The most common types of injury were muscle strains (26.14%) and ligament sprains (25%). Recurrent injuries accounted for a higher proportion of chronic injuries compared to new injuries (IPR 1.85, 95% CI 1.16-2.97).

CONCLUSION

This study described injury characteristics of high school track and field throwing athletes from 2008 to 2019. Based on our results, injury prevention may be particularly important for female throwers with prior injury.

Head Impact Kinematics and Brain Tissue Strains in High School Lacrosse

Male lacrosse and female lacrosse have differences in history, rules, and equipment. There is current debate regarding the need for enhanced protective headwear in female lacrosse like that worn by male lacrosse players. To inform this discussion, 17 high school lacrosse players (6 female and 11 male) wore the Stanford Instrumented Mouthguard during 26 competitive games over the 2021 season. Time-windowing and video review were used to remove false-positive recordings and verify head acceleration events (HAEs). The HAE rate in high school female lacrosse (0.21 per athlete exposure and 0.24 per player hour) was approximately 35% lower than the HAE rate in high school male lacrosse (0.33 per athlete exposure and 0.36 per player hour). Previously collected kinematics data from the 2019 high school male and female lacrosse season were combined with the newly collected 2021 kinematics data, which were used to drive a finite element head model and simulate 42 HAEs. Peak linear acceleration (PLA), peak angular velocity (PAV), and 95th percentile maximum principal strain (MPS95) of brain tissue were compared between HAEs in high school female and male lacrosse. Median values for peak kinematics and MPS95 of HAEs in high school female lacrosse (PLA, 22.3 g; PAV, 10.4 rad/s; MPS95, 0.05) were lower than for high school male lacrosse (PLA, 24.2 g; PAV, 15.4 rad/s; MPS95, 0.07), but the differences were not statistically significant. Quantifying a lower HAE rate in high school female lacrosse compared to high school male lacrosse, but similar HAE magnitudes, provides insight into the debate regarding helmets in female lacrosse. However, due to the small sample size, additional video-verified data from instrumented mouthguards are required.

Pulsed Red and Blue Photobiomodulation for the Treatment of Thigh Contusions and Soft Tissue Injury: A Randomized Controlled Trial

CONTEXT

Contusion and soft tissue injuries are common in sports. Photobiomodultion, light and laser therapy, is an effective aid to increase healing rates and improve function after various injury mechanisms. However, it is unclear how well photobiomodulation improves function after a contusion soft tissue injury. This study aimed to determine the effects of a pulsed red and blue photobiomodulation light patch on muscle function following a human thigh contusion injury.

DESIGN

Single-blinded randomized control trial design.

METHODS

We enrolled 46 healthy participants. Participants completed 5 visits on consecutive days. On the first visit, participants completed a baseline isokinetic quadriceps strength testing protocol at 60°/s and 180°/s. On the second visit, participants were struck in the rectus femoris of the anterior thigh with a tennis ball from a serving machine. Immediately following, participants were treated for 30 minutes with an active or placebo photobiomodulation patch (CareWear light patch system, CareWear Corp). Following the treatment, participants completed the same isokinetic quadriceps strength testing protocol. Participants completed the treatment and isokinetic quadriceps strength test during the following daily visits. We normalized the data by calculating the percent change from baseline. We used a mixed model analysis of covariance, with sex as a covariate, to determine the difference between treatment groups throughout the acute recovery process.

RESULTS

We found the active photobiomodulation treatment significantly increased over the placebo group, quadriceps peak torque during the 180°/s test (P = .030), and average power during both the 60°/s (P = .041) and 180°/s (P ≤ .001) assessments. The mean peak torque and average power of 180°/s, at day 4, exceeded the baseline levels by 8.9% and 16.8%, respectively.

CONCLUSIONS

The red and blue photobiomodulation light patch improved muscle strength and power during the acute healing phase of a human thigh contusion injury model.

Lacrosse-related injuries in boys and girls treated in U.S. emergency departments, 2000-2016

BACKGROUND

Lacrosse is one of the fastest-growing sports in the United States. Its rules regarding permitted contact differ by sex and age. There are no known studies using a nationally representative data set to analyze lacrosse injury patterns over several years by sex and age in the youth population.

METHODS

A retrospective analysis was performed using data from the National Electronic Injury Surveillance System for youth aged 11-18 years who were treated for lacrosse-related injuries in U.S. emergency departments from 2000 to 2016. Based on our review of the case narratives, we created and coded a new injury-mechanism variable. We generated national estimates from 6406 cases.

RESULTS

An estimated 206,274 lacrosse-related injuries to youths aged 11-18 years were treated in U.S. emergency departments from 2000 to 2016. The rate of injuries per 10,000 significantly increased from 1.9 in 2000 to a peak of 5.3 in 2012 (p < 0.0001), followed by a significant decrease to 3.4 in 2016 (p = 0.020). Injury mechanism, body part injured, and diagnosis differed by sex. Boys were 1.62 times (95% confidence interval (95%CI): 1.25-2.09) more likely than girls to be injured by player-to-player contact. Girls were 2.21 times (95%CI: 1.96-2.49) more likely than boys to have non-contact injuries. Overall, as age increased, the percentage of injuries from lacrosse sticks decreased and player-to-player contact increased.

CONCLUSION

Despite additional protective regulations in the sport, lacrosse is an important source of injury where we continue to see differences by sex and age. This study supports the continuation, modification, and addition of rules aimed at reducing lacrosse injury risk.

Incidence of injuries among lacrosse athletes: a systematic review and meta-analysis

OBJECTIVES

The purpose of this systematic review was to determine the incidence of injuries among lacrosse athletes and the differences in rates of injury by location and gender.

METHODS

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were implemented to conduct this systematic review.[1] The following variables were extracted from each of the included articles: location of injury, gender of patient, and incidence of injury among study population. The methodological quality of the included studies was assessed using mixed-methods appraisal tool (MMAT) version 2018.[2] Estimated rates were reported as pooled proportion with 95% CI. Rates of injury were calculated as a rate per 1000 athletic exposures (AEs), defined as an athlete participating in 1 practice or competition in which he or she was exposed to the possibility of athletic injury.

RESULTS

This study found that the highest injury rate among lacrosse athletes was to the lower leg/ankle/foot with a rate of 0.66 injuries per 1000 AEs (95% CI, 0.51, 0.82). This injury pattern was also found to be the highest among both male and female lacrosse athletes. No statistical significance was detected when comparing rates of injury across gender, regardless of location. The injury pattern with the lowest rates of injury for female athletes being to the shoulder/clavicle and the neck for male athletes.

CONCLUSION

The highest rate of injury among lacrosse athletes was to the lower leg/ankle/foot. As participation in lacrosse continues to rise, there is a greater need for understanding the rate of injury and injury characteristics for physicians and trainers to provide effective care to lacrosse athletes.

Descriptive Epidemiology of Campus Recreation Injuries

Campus recreation is an underserved population lacking specific medical standards, access to on-site medical personnel, and a universal injury surveillance system. The purpose of this study was to retrospectively examine injury epidemiology within a campus recreation center across 4 years. A total of 1,680 injuries were analyzed from one U.S. university with the greatest number of injuries occurring in intramural sports, informal recreation, and club sports, respectively. Of all injuries reported, 73% were musculoskeletal in nature and 9% were from concussions. As most injuries fall outside the scope of basic first aid, on-site medical services should be considered for all campus recreation settings.

Injuries in Canadian high school boys’ collision sports: insights across football, ice hockey, lacrosse, and rugby

Background

Collision sport participation rates among high school youth in Canada are high. While participation is beneficial for physical and mental well-being, the rates of injury in these sports are high.

Aims

This study aims to compare injury rates and profiles across four common youth collision sports (ice hockey, tackle football, lacrosse, rugby).

Methods

Data from a cross-sectional questionnaire of 2029 high school youth were used to identify male collision sport participants to be included in this secondary analysis (n = 360).

Results

Of the 2029 students who completed the questionnaire, 360 participated in collision-based sports [Ages: 14 (5%), 15 (41%), 16 (25%), 17 (26%), 18 (3%)]. The rates of injury ranged from 12.7 injuries/100 participants/year (rugby) to 33.1 injuries/100 participants/year (ice hockey). Concussion rates ranged from 12.4 (football) to 15.8 (ice hockey) concussions/100 participants/year. Similarities existed in the profile of injuries between sports, with most injuries occurring due to contact with another player (range 57.0% to 87.5%). Injuries to the head (33.3%), wrist/hand (16.0%), shoulder (12.8%), and knee (12.0%) were the most prevalent injury type. Substantial differences in previous playing experience existed between sports.

Discussion

The high rate of injury and concussion reported across each of these sports highlights the need for the introduction of primary prevention strategies in these sports aimed to reduce the risk of injury.

The Epidemiology of Youth Sport-Related Shoulder Injuries: A Systematic Review

Background

Youth around the globe place their shoulders at risk for injury when participating in sports. Shoulder injuries may vary in severity, produce the potential for time-loss from sport, and result in functional disability. We sought to explore sport-related shoulder injuries in youth by identifying injury rates, risk factors, injury mechanisms, and injury prevention strategies.

Methods

All relevant full-text articles were identified by searching MEDLINE, EMBASE, CINAHL, Sport Discus, and the Cochrane Controlled Trials Registry. No date restrictions were used. All full-text studies reporting original research describing sport-related shoulder injury among female and/or male youth from 5 to 18 years old were included.

Results

Of 3,889 studies screened, 97 described shoulder injury in youth sports. Shoulder injuries were identified in 24 unique sports. The median seasonal prevalence of shoulder injury was 10.9% (range 1.2-28.2%). The most common injury mechanisms identified were contacted with another player, contact with the playing environment, and falling to the ground. Risk factors for shoulder injury identified were side-to-side strength imbalances, weak external rotator muscles, and scapular dyskinesia. One study evaluated a successful training strategy to prevent shoulder injuries, but two other interventions demonstrated no effect.

Conclusions

Sport-related shoulder injuries are prevalent among youth athletes. Injury risk factors identified included modifiable intrinsic factors such as strength, range of motion, and training load. The most common injury mechanism was direct contact with either another person or an object in the playing environment. Innovative shoulder-specific strategies are needed to reduce shoulder injuries in this population. Trial Registration: PROSPERO ID: CRD42020189142.

Epidemiology of NCAA Track and Field Injuries From 2010 to 2014

Background:

Track and field (T&F) athletes compete in a variety of events that require different skills and training characteristics. Descriptive epidemiology studies often fail to describe event-specific injury patterns.

Purpose:

To describe the epidemiology of injuries in National Collegiate Athletic Association (NCAA) T&F by sex, setting (practice vs competition), and time of season (indoor vs outdoor) and to compare injury patterns by events within the sport.

Study Design:

Descriptive epidemiology study.

Methods:

Data were obtained from the NCAA Injury Surveillance Program for all indoor and outdoor T&F injuries during the academic years 2009-2010 to 2013-2014. Injury rates, injury rate ratios, and injury proportion ratios (IPRs) were reported and compared by sex, injury setting, season, and event. Analysis included time-loss as well as no-time loss injuries.

Results:

Over the 5 seasons, the overall injury rate was 3.99 injuries per 1000 athletic-exposures (95% CI, 3.79-4.20). After controlling for injury diagnoses, women’s T&F athletes experienced an 18% higher risk of injury (95% CI, 7% to 31%) and missed 41% more time after an injury (95% CI, 4% to 93%) when compared with men. Among all athletes, the injury risk during competition was 71% higher (95% CI, 50% to 95%) compared with practice and required 59% more time loss (95% CI, 7% to 135%). Distance running accounted for a significantly higher proportion of overuse injuries (IPR, 1.70; 95% CI, 1.40-2.05; P < .05) and required 168% more time loss (95% CI, 78% to 304%) than other events. The hip and thigh were the body regions most commonly injured; injury type, however, varied by T&F event. Sprinting accounted for the greatest proportion of hip and thigh injuries, distance running had the greatest proportion of lower leg injuries, and throwing reported the greatest proportion of spine and upper extremity injuries.

Conclusion:

Injury risk in NCAA T&F varied by sex, season, and setting. Higher injury rates were found in women versus men, indoor versus outdoor seasons, and competitions versus practices. The hip and thigh were the body regions most commonly injured; however, injury types varied by event. These findings may provide insight to programs aiming to reduce the risk of injury and associated time loss in collegiate T&F.

Hand and wrist injuries among collegiate athletes vary with athlete division

BACKGROUND

The rates, severity and consequences of hand and wrist injuries sustained by National Collegiate Athletic Association athletes are not well characterized. This study describes the epidemiology of hand and wrist injuries among collegiate athletes competing in different divisions.

METHODS

The National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) was accessed from 2004 to 2015 for the following sports: baseball, basketball, football, ice hockey, lacrosse, soccer, wrestling, field hockey, gymnastics, softball and volleyball. The data were used to identify all hand and wrist injuries, the specific injury diagnosis, mean time loss of activity following injury, and need for surgery following injury. These were then stratified by gender. Descriptive statistics were performed to examine the association between sports, event type and division. Student's t test was used to calculate p-values for independent variables. Chi-Square test was used to calculate odds ratio. P < 0.05 was considered significant.

RESULTS

103,098 hand and wrist injuries were reported in in the studied NCAA sports from 2004 to 2015. Male athletes sustained 72,423 injuries (6.01/10,000 athlete exposure) and female athletes sustained 30,675 injuries (4.13/10,000 athlete exposure). Division I athletes sustained significantly more injuries compared to divisions II and III. Overall, 3.78% of hand and wrist injuries required surgical intervention. A significantly higher percentage of division I athletes (both male and female) underwent surgical intervention compared to divisions II and III. The mean time lost due to hand and wrist injury was 7.14 days for all athletes. Division I athletes missed the fewest days due to injury at 6.29 days though this was not significant.

CONCLUSIONS

Hand and wrist injuries are common among collegiate athletes. Division I athletes sustain higher rates of injuries and higher surgical intervention rates, while tending to miss fewer days due to injury. Improved characterization of divisional differences in hand and wrist injuries can assist injury management and prevention.

Epidemiology of Injuries in National Collegiate Athletic Association Men's Lacrosse: 2014-2015 Through 2018-2019

CONTEXT

The popularity of National Collegiate Athletic Association (NCAA) men's lacrosse has been steadily increasing since the early 1980s.

BACKGROUND

Injury surveillance is an important tool to aid in identifying emerging patterns of sport-related injury in NCAA men's lacrosse.

METHODS

Injury data collected from a sample of men's lacrosse teams through the NCAA Injury Surveillance Program for the academic years 2014-2015 through 2018-2019 were analyzed. Athlete exposures were estimated and computed based on collected exposure data. Injury counts, rates, and proportions were used to describe injury characteristics, and injury rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated to estimate differences in injury rates.

RESULTS

The overall injury rate was 4.90 per 1000 athlete exposures (AEs), and the competition injury rate was higher than the practice injury rate (IRR = 2.59; 95% CI = 2.35, 2.84). The overall preseason injury rate was higher than the regular and postseason injury rates. The most reported injuries were concussions (8.0%), ankle sprains (7.7%), and hamstring tears (6.9%).

CONCLUSIONS

Study findings were comparable with existing epidemiological evidence. The overall burden of concussions and lower extremity injuries warrant further attention in this population.

Methods of the National Collegiate Athletic Association Injury Surveillance Program, 2014-2015 Through 2018-2019

BACKGROUND

Since 1982, the National Collegiate Athletic Association (NCAA) has collaborated with athletic trainers (ATs) to create the largest ongoing collegiate sports injury database in the world. This report provides an operational update of the NCAA Injury Surveillance Program (NCAA ISP) during the academic years 2014-2015 through 2018-2019.

SURVEILLANCE SYSTEM STRUCTURE

The NCAA ISP used a convenience sampling technique via a rolling recruitment model. The ATs at contributing institutions voluntarily submitted data into their respective electronic medical record systems; common data elements were pushed to and maintained by the Datalys Center. The ATs provided information about all team-related activities, even if no injury occurred during that activity, as well as detailed reports on each injury, including condition and circumstances.

SUMMARY

The NCAA ISP has a long-standing role in supplying NCAA stakeholders with crucial injury surveillance data, playing a critical part in safeguarding student-athletes participating in collegiate sports.

Men's Lacrosse Injuries in the 2018 International World Championship Play

Background:

Limited data exist on injuries in men’s lacrosse at the international level. As lacrosse’s popularity grows rapidly across the globe, health care providers must understand how to treat lacrosse athletes.

Purpose:

To analyze injury data from the 2018 Men’s World Lacrosse Championship.

Study Design:

Descriptive epidemiology study.

Methods:

This study prospectively observed injuries that occurred during the 2018 Men’s World Lacrosse Championship. The medical staff of each team completed injury report forms, and data were categorized into body part injury, type, mechanism, time, and location of injury.

Results:

Over 11 days, 1019 athletes competed in 170 games, resulting in a total of 7147 athlete-exposures (AEs). A total of 140 injuries were recorded during the tournament for an injury rate of 19.6 per 1000 AEs (95% CI, 16.4-22.7). Overall, there were more contact injuries (n = 99; 70.7%) than noncontact injuries (n = 41; 29.3%) (P < .0001). Contact injuries most commonly affected the upper extremity, while noncontact injuries most commonly affected the lower extremity. Contusions were the most commonly reported injury type in the tournament (n = 41; 29.3%), followed by ligament sprains (n = 32; 22.9%) and muscle strains (n = 21; 15.0%). Although there was no difference between the first and second half of gameplay, the injury rate increased in the latter portion of each half (the first and third quarters vs the second and fourth quarters) (P < .0001). A total of 4 injuries required trips to the hospital.

Conclusion:

Lacrosse has a unique injury profile, as it includes both overhead and collision activity as well as multidirectional, cutting movements. Understanding common injury patterns may help with treatment and prevention. Fatigue may play a role in injury rate, and future research of within-game and within-tournament fatigue should explore this relationship.

Data-Driven Risk Classification of Concussion Rates: A Systematic Review and Meta-Analysis

BACKGROUND

Concussion is a growing public health concern and generating concussion prevention programs depends on identifying high-risk sports and characteristics. Identifying the roles of sport, sex, and participation level (e.g., high school versus collegiate athletics) in concussion risk would facilitate more informed decision-making regarding sports participation and generate better targeted prevention strategies.

OBJECTIVES

The current study's objectives were to: (1) determine the magnitude and hierarchy of sports-related concussion (SRC) risk across an array of events and (2) evaluate the modifying roles of sex, participation level, and session type on SRC rates.

METHODS

A literature search was conducted on PubMed, searching concussion studies published between 2001 and December 2019. Inclusion criteria for studies required: (1) concussion occurred during sport, (2) that the SRC was clinically diagnosed, and (3) athlete exposures and concussions could be extracted or estimated. A study was excluded if it: (1) was not an original research article, (2) was not written in English language, (3) was an animal study, (4) did not have enough data to calculate SRC rates, (5) included professional or youth sample, and/or (6) contained data collected prior to 2001. The meta-analysis and meta-regression analyses were fit using a random effects model.

RESULTS

Search results returned 2695 unique research articles, with 83 studies included in analyses. Sport, sex, participation level, and session type all significantly influenced SRC rates. Overall, rugby had the highest concussion rate and was classified as the highest risk sport (28.25 concussions per 10,000 athlete exposures). Overall, females had a higher concussion rate than males. Only lacrosse demonstrated a higher concussion rate for males compared to females. Collegiate athletes had higher concussion rates than high school athletes. Games were associated with 2.01 more concussions per 10,000 AEs than practices.

CONCLUSIONS

This meta-analysis demonstrated rugby has the highest concussion risk, followed by American Football, ice hockey, and wrestling. Concussion risk was influenced by sport, sex, participation, and session. Identifying the factors and environments that influence concussion risk can facilitate risk reduction and prevention strategies.

Epidemiology of Sport-Related Concussion

Sport-related concussions are common in the United States. Concussion rates have increased over time, likely due to improved recognition and awareness. Concussion rates vary across level (high school vs college), sex, and sport. Concussion rates are the highest among men, particularly in football, wrestling, ice hockey, and lacrosse where collisions and contact are inherent to the sports, although girls'/women's soccer rates are high. In gender-comparable sports, women have higher concussion rates. Continued data collection will increase understanding of sport-related concussion and provide areas for targeted prevention in the future.

Are high school girls' lacrosse players at increased risk of concussion because they are not allowed to wear the same helmet boys' lacrosse players are required to wear?

BACKGROUND

Boys' lacrosse (LAX), a full contact sport allowing body and stick checking, mandates hard shell helmets with full face masks. Girls' LAX, which prohibits body checking and whose sphere rule is supposed to prevent stick checking to the head, allows optional flexible headgear with/without integrated eye protection. Whether the required boys' LAX helmets should also be mandated in girls' LAX has been debated.

METHODS

In this retrospective cohort study we used LAX concussion data from a national high school sports-related injury surveillance study to determine if girls' LAX players were at increased risk of concussion from stick or ball contact due to differences in helmet regulations by calculating the attributable risk and attributable risk percent (AR%) for concussion resulting from ball or stick impacts.

RESULTS

From 2008-09 through 2018-19, boys' LAX players sustained 614 concussions during 1,318,278 athletic exposures (AEs) (4.66 per 10,000 AEs) and girls' LAX players sustained 384 concussions during 983,291 AEs (3.91 per 10,000 AEs). For boys, athlete-athlete contact was the most common mechanism of concussion accounting for 66.4% of all concussions, while stick or ball contact accounted for 23.5%. For girls, stick or ball contact accounted for 72.7% of all concussions, while athlete-athlete contact accounted for 19.8%. Concussion rates from stick or ball contact were significantly higher in girls vs. boys (RR = 2.60, 95% CI 2.12-3.18). The attributable risk associated with playing girls' vs. boys' LAX for concussion resulting from stick or ball contact was 1.75 concussions per 10,000 AEs (95% CI 1.37-2.12) and the AR% was 61.5% (95% CI 52.9-68.5). An estimated 44.7% of all girls' LAX concussions could have been prevented if girls' LAX players wore the helmet mandated in boys' LAX.

CONCLUSIONS

Girls' LAX players who are allowed, but not required, to wear a flexible headgear are at increased risk of concussions from stick or ball impacts compared to boys' LAX players, who are required to wear a hard shell helmet with full face mask. Additional research is needed to determine if there are any defendable arguments to continue justifying restricting girls' LAX players access to this effective piece of protective equipment.