Sex- and Age-Specific Review of Flag Football Injuries in the United States: A 10-Year Analysis of National Injury Data

Abstract

Context:

Flag football is a rapidly growing sport with injuries frequently presenting to emergency departments (EDs). Current literature on flag football lacks mechanisms of injury and any information pertaining to female athletes. The purpose of this study was to examine demographic-specific injury trends in those playing flag football.

Evidence Acquisition:

The National Electronic Injury Surveillance System (NEISS) was queried for flag football injuries presenting to United States EDs from January 1, 2013 to December 31, 2022. Patient demographics, injury site, diagnosis, and disposition were recorded. NEISS narratives were used to identify mechanisms of injury. National estimates (NEs) were calculated using the NEISS statistical sample weight. Annual injury trends were evaluated by linear regression.

Study Design:

Descriptive epidemiology study.

Level of Evidence:

Level 3.

Results:

There were 2508 flag football injuries (NE, 86,443) analyzed from 2013 to 2022; 78.2% were sustained by male athletes. Linear regression analysis revealed no significant trend in annual injuries (P = 0.16) from 2013 to 2022. The most common mechanism of injury was player-player collision (35.7%). The 2 age groups most affected by flag football injuries were middle school-aged (11-13 years) (20.8%) and high school-aged (14-18 years) (23.7%). The area of the body most affected for pediatric (<18 years) groups was the head, while adults most frequently injured their fingers. In addition, the most common mechanism for the pediatric age group was fracture (21.3%), whereas adult age groups most frequently suffered from strain/sprain injuries.

Conclusion:

The number of injuries from flag football identified in this study has not decreased throughout the last decade, aside from 2020 - potentially due to the prevalence of COVID-19. Collisions were the most frequent mechanism of injury across all age groups. Whereas younger athletes frequently sustained head injuries and fractures, older athletes typically sustained strain/sprain injuries and finger injuries.

Flag football is a sport designed to mirror traditional American football while minimizing contact during play. With rising awareness of player safety and increased media coverage, many players are opting to play flag football to avoid injury.^6,15 Repetitive concussions and head trauma can occur while playing traditional tackle football, prompting many youth, adolescent, and adult athletes to turn to flag football as a potentially safer alternative. ¹⁵

The number of flag football players has increased across the United States (US), with a 39% increase since 2020.^3,15 For the young and inexperienced athlete, flag football can serve as a gateway to learning proper techniques and body mechanics necessary to play tackle football safely. For older players, the sport provides an opportunity to remain physically active while minimizing the risk of injury. According to Roghair et al, ¹² there are 2.8 million kids in the US currently participating in flag football. ¹⁰ This number is only expected to grow, as a recent American Academy of Pediatrics Policy Statement recommends the expansion of flag football to mitigate injuries associated with tackling injuries. ¹⁴ With new participants emerging globally, awareness of safety protocols in flag football is more important than ever, as flag football is slated to debut as an official women’s National Collegiate Athletic Association (NCAA) sport in 2025 and the Olympic Games in 2028.

As flag football participation among American youth and older adults has climbed, so has research centered around motivations in participation and injuries sustained by players.^{1,3,6,7,10,13,16} In a study by Foss et al, ³ the head/face/neck region was found to be the most common injury site, and females had a higher risk of overall injury. Furthermore, contusions and sprains/subluxations were the most common types of injuries. ³ Although head injuries are present in flag football, a study by Waltzman et al ¹⁵ underscores its relative safety compared with tackle football, which resulted in 14.67 times more head impacts. ⁵ However, there is a paucity of data concerning age- and sex-specific injury patterns in flag football. In addition, the mechanisms of injury specific to this sport remain largely undefined.

Despite the rapid growth in flag football, to our knowledge there is no study that utilizes a nationally representative cohort to assess the distribution and underlying mechanisms for flag football injuries. In this study, we used the National Electronic Injury Surveillance System (NEISS) to evaluate the primary mechanisms of injury, location of injury, and epidemiologic trends in flag football injuries by age and sex. We hypothesized that (1) a majority of examined injuries would be contact-related injuries, (2) the head would be the most affected body part, and (3) injury frequency would not be increasing despite the continued growth of the sport.

Methods

Database

The Consumer Product Safety Commission’s NEISS is a public, national deidentified database. This database collects visits to US emergency departments (EDs) as a probability sample from designated hospitals across the country that are stratified by geographic location and size. The included hospitals are grouped into 1 of 5 categories: 4 of them represent hospital EDs of varying sizes and the fifth is EDs from children’s hospitals. Using sample weights that are assigned to each of the EDs included in the dataset, national estimates (NEs) may be calculated for injuries across the US based on the raw NEISS case data.

Data Extraction

The NEISS database was queried retrospectively for all injuries related to flag football from January 1, 2013 to December 31, 2022. There were 2508 cases of injuries related to flag football that were extracted. Included in each case file in NEISS is the date of ED visit, age, sex, race/ethnicity, injury diagnosis, injured body part, and discharge disposition. Age was then categorized into 1 of 6 groups: young child (0-10 years), middle school aged (11-13 years), high school aged (14-18 years), college aged (19-23 years), young adult (24-30 years), and adult (≥31 years).

The narrative provided for each patient case was reviewed by the authors to identify the mechanism of injury. These mechanisms of injury were attained through retrospective review of each individual case and subsequently categorized. Collisions included any injury that occurred as a result of contact between ≥2 players. Fall injuries referred to injuries where a player hit/collided with the ground. Flag pull injuries involved injuries sustained while attempting to pull a flag. Twist injuries referred to twisting, rolling, inverting, etc, of a joint. Overuse injuries were made up of chronic strain/sprain injuries. Any injury that did not meet one of these criteria was coded as “other mechanism.” Injury narratives that did not provide details regarding the injury mechanism were coded as “not specified.”

Exclusion Criteria

Injuries that presented to EDs that were not sustained while playing flag football were excluded (weight lifting workouts during football practice, spectator or fan injuries at a flag football game, band injury at halftime of football game, etc). Injuries that occurred playing tackle football or any other rules than flag football were also excluded.

Statistical Analysis

IBM SPSS Statistics Version 28.0 was used for this data analysis. Descriptive statistics (reported in NEISS cases, NE, and associated percentages) were utilized when determining the breakdown by sex, age, race, injury mechanism, and injured body part. When assessing sex-specific differences in frequency of injury, injured body part, or mechanism of injury, Pearson’s chi squared analysis was used. To evaluate annual trends in flag football injuries, linear regression analysis was used. In this analysis, the year of injury was the independent variable and the number of injuries sustained while playing flag football was the dependent variable. Diagnosis and injured body part were also examined across the study period with linear regression. P values and 95% CI are reported and the level of statistical significance is set at P < 0.05.

Results

An estimated total of 86,444 NE (2508 NEISS cases) flag football injuries presented to US EDs between January 1, 2013 and December 31, 2022. Injuries occurred predominantly in male athletes (76%). Among all age groups, the high school group was the most affected (NE, 20,534; 24%), followed by the middle school age group (NE; 17,940; 20.75%). The lowest number of injuries were seen in those <10 years old (NE, 8930; 10.33%) (Table 1).

Table 1.

Demographic characteristics of flag football NEISS cases and nationally estimated injuries from January 1, 2013 to December 31, 2022.

		NEISS Cases	NE	Percentage
Sex	Male	1961	65,371	75.62
	Female	547	21,073	24.38
	Total	2508	86,444	100
Age group, years old	Young child, 0-10	350	8930	10.33
	Middle school, 11-13	568	17,940	20.75
	High school, 14-18	562	20,534	23.75
	College, 19-22	410	14,954	17.3
	Young adult, 23-30	362	13,175	15.24
	Adult, ≥31	256	10,911	12.63
	Total	2508	86,444	100

NE, national estimate; NIESS, National Electronic Injury Surveillance System.

Linear regression analysis of annual injuries between 2013 and 2022 demonstrated no significant trend in annual injuries (P = 0.16; R² = 0.20; β = −0.331; 95% CI, –826 to 163). The number of injuries remained relatively constant from 2013 to 2019 (NE, 9150-10,582), with a decrease of 79.1% in 2020 (NE, 2211), which then returned to a similar level (NE, 8405) by 2022 (Figure 1).

Figure 1.

NEs of flag football-related injuries presenting to US EDs during study period (2013-2022). ED, emergency department; NE, national estimate; US, United States.

Player collision was the most common mechanism of injury for every age group, making up 35.3% of all injuries (NE, 29,080) (Figure 2).

Figure 2.

Mechanisms of injury in study cohort. FOOSH, fallen onto an outstretched hand.

Fracture was the most frequent diagnosis among the youth, middle school, and high school age groups, accounting for 21.3% of injuries in the 0- to 10-year-old group, 29.7% of injuries in the middle school age group, and 22.3% in the high school age group (Table 2). The head was the body part affected most frequently for the pediatric groups, making up 25.8% of injuries in the younger than middle school group, 20.6% for the middle school group, and 22.2% for the high school group. For young adults, adults, and the college age group, fingers became the most affected body part, making up 18.3%, 17.1%, and 17.9% of injuries for the college age, young adult, and adult age groups, respectively.

Table 2.

Most frequent mechanisms of injury and diagnosis by age group

Age group, years old	Top 3 mechanisms	Top 3 diagnoses
Young child, 0-10	1. Player collision (37%)	1. Fracture (21.3%)
	2. Fall injury (34.2%)	2. Strain/sprain (17.4%)
	3. Flag pull (13%)	3. Contusion/abrasion (15.5%)
Middle school, 11-13	1. Player collision (31.6%)	1. Fracture (29.7%)
	2. Fall injury (30.2%)	2. Strain/sprain (25.2%)
	3. Flag pull (22.6%)	3. Concussion (13.4%)
High school, 14-18	1. Player collision (35.1%)	1. Strain/sprain (24.7%)
	2. Fall injury (26.7%)	2. Fracture (22.3%)
	3. Flag pull (20.0%)	3. Concussion (13.4%)
College, 19-22	1. Player collision (32.4%)	1. Strain/sprain (24.9%)
	2. Fall injury (29.3%)	2. Fracture (17.8%)
	3. Flag pull (21.2%)	3. Dislocation (14.1%)
Young adult, 23-30	1. Player collision (35.3%)	1. Strain/sprain (32.7%)
	2. Fall injury (25.4%)	2. Fracture (20.6%)
	3. Flag pull (15.6%)	3. Dislocation (9.9%)
Adult, ≥31	1. Player collision (31.3%)	1. Strain/sprain (35.8%)
	2. Fall injury (29.7%)	2. Fracture (18.2%)
	3. Overuse injury (14.6%)	3. Dislocation (10.9%)

When stratified by sex, the greatest proportion of injuries sustained by male athletes was the middle school age group (21.14%), whereas the age group injured most frequently for female athletes was the high school age group (34.87%) (Figure 3). Both male and female athletes were injured most frequently by player collision, and then by fall/ fallen onto an outstretched hand (FOOSH) (Figure 4). The most injured body part for male athletes across all groups was the head (16.87%), whereas female athletes most frequently injured the finger (20.26%).

Figure 3.

Proportion of injuries by age group, comparing male and female players.

Figure 4.

Mechanism of injuries by sex.

Discussion

This study revealed that the head was the body part injured most frequently in pediatric populations and that head injury was more common in male than female players. The number of injuries did not change significantly throughout the study period, remaining fairly constant between 2013 and 2019, decreasing in 2020, likely due to the COVID-19 pandemic, and returning to baseline by 2021. In addition, it was discovered that among adult athletes, the finger was the body region injured most commonly. Interestingly, the 2 groups that sustained the greatest proportion of injuries in flag football were the middle school and high school age groups. Despite being the case, this finding may be due to the greatest proportion of players being from these age groups. Finally, player collision was the most common mechanism of injury across all age groups.

On a positive note, despite an overall increase in flag football participation, including a 39% increase in the past 3 years, ³ there was no significant increase in number of injuries. Although participation has increased in recent years, a concomitant increase in injury frequency was not observed. The existing literature remains conflicted on the potential harm that can still occur in flag football, even though flag football was designed to be a safe alternative to tackle football. According to a study by Lynall et al, ⁹ youth flag football players were less likely to sustain collision injuries to the head, but were more likely to sustain high acceleration injuries to the head compared with tackle football youth counterparts. In addition, a study by Sarmiento et al ¹³ demonstrated that, although the incidence was less than in tackle football players, flag football players could still expect to sustain 0.37 head impacts during a practice and 0.77 head impacts during a game. A third study by Foss et al ³ suggested that although the actual rate of collisions and injury in flag football were lower than those in tackle football, the sites of injury and mechanisms very closely mirror tackle football, indicating further protective protocols may still need to be put into place. Surprisingly, a study by Peterson et al ¹⁰ suggests that youth flag football players may be even more likely to sustain a concussion than youth tackle football players, with no significant difference in severe injuries between youth tackle and flag football leagues.

This study corroborates previous findings on the number of flag football collision injuries and found that contact injuries by collision were the most common injury mechanism across all age groups. This is an alarming finding, given the original purpose of flag football was to avoid unnecessary contact. According to a study by Foss et al, ³ 74.5% of injuries from flag football were a result of direct impact. This is a critical concern as flag football has become an increasingly popular alternative to traditional tackle football for youth athletes, National Football League players during the Pro Bowl, Olympic athletes, and as a lower-impact alternative for both male and female athletes. With a current lack of literature on the distribution of injuries in the sport of flag football and its safety relative to tackle football, it is imperative that measures are taken to protect player safety as the sport continues to rise in popularity. Given that collision and flag pull injuries are 2 of the highest prevalence, it would be wise to conduct further research on head injury and the efficacy of head protection during these games. For flag pull injuries, many mechanisms noted broken fingers and hands after getting stuck in a player’s flag belt. Further considerations should be taken to modernize the flag belt to deter further injuries of this type, such as adding flag clips to the shorts players wear to eliminate the potential for hands and fingers to get stuck in another player’s belt. Certain rules exist to combat these injuries in organized leagues, such as the “no pocket rule” in which players may not have pockets in their shorts to avoid finger and wrist injuries. ⁴ Foss et al ³ demonstrated that removing pockets decreased injuries sustained to the fingers including the thumb.

Another interesting finding were the differences by age group. The body part injured most commonly for the 3 youth and adolescent age groups was the head. Despite existing orthopaedic literature confirming that tackle football head-injury risk is significantly higher than that of flag football,^10,13,15 head injury still made up the greatest proportion of injuries for youth and adolescent age groups in this study. The most common diagnosis experienced by the youth and adolescent athletes was fractures. This is supported by the existing literature, suggesting that fracture rates among adolescent athletes may be twice as high as that of adult athletes.^1,2 The most common diagnoses for injury in the adult age groups were strain and sprain, potentially indicating a high number of overuse injuries in the adult players. A study by Kaplan et al ⁵ suggested that fitting adult players with proper ankle braces would be able to combat this issue, decreasing the prevalence of ankle sprain by a significant margin.

With respect to sex-specific differences, there is very little literature discussing women’s injury prevalence in a flag football context. A study by Pirruccio et al ¹¹ discussed the necessity for further research into female player head injuries, stating that participation rates do not explain the rising trends in head injuries for high school age female athletes. Female flag football players suffered roughly 25% of all injuries, with high school athletes being the most commonly injured. When examining how these injuries occurred, both male and female athletes sustained a majority of injuries through player collision, followed by fall. Of note, a study by Lin et al ⁸ suggests that female athletes were more likely than male athletes to sustain a concussion when colliding with equipment in a variety of sports. Female flag football players overall had a higher risk ratio and injury rate ratio compared with male players. ³ Given the contrasting data with regard to female athletes in flag football, further sex-specific epidemiologic research may aid in understanding prevalence and causes of injury for female athletes in flag football, particularly as the participation of female athletes in this sport continues to rise and the inaugural season of women’s NCAA flag football approaches.

Limitations

The NEISS dataset is a cross-sectional probability sample and therefore does not represent an exact number of all national cases that presented to US EDs over the study period. Therefore, the data acquired for this study represent a “best estimate” and reflect the proportions of injuries across this study group as opposed to injury prevalence or rate. This may limit the further comparison of data with sports with a more robust body of evidence such as tackle football. In addition, the dataset only includes injuries that are severe enough for patients to report to the ED for diagnosis and management. This potentially omits patients who managed injuries on their own or presented to urgent care clinics or other healthcare provider offices. Characterizing injury mechanisms relied on the limited detail available in the NEISS case narratives, which likely had inaccuracies in characterization. Given that these mechanisms were categorized through manual review of case narratives, the data should be interpreted with caution. Finally, specific information about rules and equipment used, such as the number of flags, amount of players on field, and presence or absence of protective equipment, are not included in NEISS, and therefore this study was unable to quantitatively assess the true efficacy of safety equipment.

Conclusion

This study demonstrated no significant trends in the number of annual injuries, despite flag football’s growing popularity in the US. Player collisions made up a majority of injury mechanisms across all age groups, and the head was the body part injured most frequently among pediatric populations. Male patients sustained a greater number of injuries in this study, and differences in mechanism of injury and diagnosis were observed for the different age groups examined in this study.