Comparison of injuries sustained on artificial turf and grass by male and female elite football players

The objective of this study was to compare incidences and patterns of injury for female and male elite teams when playing football on artificial turf and grass. Twenty teams (15 male, 5 female) playing home matches on third‐generation artificial turf were followed prospectively; their injury risk when playing on artificial turf pitches was compared with the risk when playing on grass. Individual exposure, injuries (time loss) and injury severity were recorded by the team medical staff. In total, 2105 injuries were recorded during 246 000 h of exposure to football. Seventy‐one percent of the injuries were traumatic and 29% overuse injuries. There were no significant differences in the nature of overuse injuries recorded on artificial turf and grass for either men or women. The incidence (injuries/1000 player‐hours) of acute (traumatic) injuries did not differ significantly between artificial turf and grass, for men (match 22.4 v 21.7; RR 1.0 (95% CI 0.9–1.2); training 3.5 v 3.5; RR 1.0 (0.8–1.2)) or women [match 14.9 v 12.5; RR 1.2 (0.8–1.8); training 2.9 v 2.8; RR 1.0 (0.6–1.7)]. During matches, men were less likely to sustain a quadriceps strain (P=0.031) and more likely to sustain an ankle sprain (P=0.040) on artificial turf.     

Risk factors for injuries in elite female soccer players

Objective

To describe risk factors for injuries in elite female soccer.

Methods

A total of 143 female soccer players from the German national league participated in the study. Baseline information on player characteristics—for example, anthropometric measurements and playing position—and medical history were recorded at the start of the study. During one outdoor season, injuries and training and match exposure times were prospectively documented for each player.

Results

The risk of a new anterior cruciate ligament (ACL) rupture was significantly increased in players with a previous rupture (odds ratio (OR)  =  5.24, p  =  0.01). This was not the case for ankle sprain (OR  =  1.39) or knee sprain (OR  =  1.50). In addition, no significantly increased risk of new sprains or ACL ruptures was found when the injured leg was the unit of analysis. Injury incidence was considerably higher in defenders (9.4 injuries per 1000 hours exposure) and strikers (8.4/1000 hours) than goalkeepers (4.8/1000 hours) and midfielders (4.6/1000 hours). Ten per cent of all players (n  =  14) sustained more than three injuries. Most of these were defenders (n  =  8) or strikers (n  =  4). Significantly more injuries occurred to the dominant leg (105 v 71, p  =  0.01); this was particularly true for contact injuries (52 v 29, p  =  0.01).

Conclusions

Injury risk should be assessed on an individual basis. Therefore it seems appropriate to individualise preventive training programmes, as is recommended for other training content. Evaluating the existing rules of soccer and their appropriate application may also help to decrease injury risk, particularly in contact situations.     

Stress fractures in elite male football players

The objective was to investigate the incidence, type and distribution of stress fractures in professional male football players. Fifty‐four football teams, comprising 2379 players, were followed prospectively for 189 team seasons during the years 2001–2009. Team medical staff recorded individual player exposure and time‐loss injuries. The first team squads of 24 clubs selected by UEFA as belonging to the 50 best European teams, 15 teams of the Swedish Super League and 15 teams playing their home matches on artificial turf pitches were included. In total, 51 stress fractures occurred during 1 180 000 h of exposure, giving an injury incidence of 0.04 injuries/1000 h. A team of 25 players can therefore expect one stress fracture every third season. All fractures affected the lower extremities and 78% the fifth metatarsal bone. Stress fractures to the fifth metatarsal bone, tibia or pelvis caused absences of 3–5 months. Twenty‐nine percent of the stress fractures were re‐injuries. Players that sustained stress fractures were significantly younger than those that did not. Stress fractures are rare in men's professional football but cause long absences. Younger age and intensive pre‐season training appear to be risk factors.     

Soccer injuries in Iceland

We investigated the frequency, cause and location of injuries in Icelandic elite soccer in 1991. The incidence of injuries for the individual player was 34.8 ± 5.7 per 1000 game-hours and 5.9 ± 1.1 per 1000 practice-hours. The most common types of injuries were muscle strains (29%), ligament sprains (22%), contusions (20%), and other injuries (29%). The frequency of reinjury was markedly high, where 44% of the strains and 58% of the sprains were registered as reinjuries. Strains occurred mainly during sprinting, sprains by tackling, and contusion during other contact. Significantly more injuries occurred on artificial turf than on grass or gravel in correlation to number of hours in games and practices. Teams who had the longest pre-season preparation period obtained significantly fewer injuries during the season.     

Lifetime prevalence of injuries in incoming division I collegiate football players

Objectives: The purpose of this study is to determine the lifetime prevalence of past injuries in incoming first year football players in a Division 1 college football team.

Methods: Pre-participation questionnaires from 605 first-year football players over 20 years (1996–2015) were examined to determine the prevalence of concussions, stingers, fractures, and musculoskeletal surgeries sustained before playing at the collegiate level. Players were grouped by position: wide receiver and defensive back (WR/DB), offensive and defensive linemen (OL/DL), all other positions (OP), and unknown (UKN). Prevalence of injuries by year and position was compared using Pearson’s χ² Test (p < 0.05).

Results: The reported lifetime prevalence is as follows: concussion (21%), stinger (23%), musculoskeletal surgery (23%), and fracture (44%). There were no significant differences in lifetime prevalence of concussions (p = 0.49), stingers (p = 0.31), fractures (p = 0.60), or musculoskeletal surgeries (p = 0.97) based on position. There were also no significant differences in the lifetime prevalence of concussions (p = 0.14), musculoskeletal surgeries (p = 0.50), or fractures (p = 0.59) based on year. However, there was a significant difference in the lifetime prevalence of stingers based on year (p < 0.001).

Conclusions: There was an expectation to observe an increase in injury prevalence by entering year, but this was not seen. A decrease in stingers was actually observed, but there was no significant difference among any other injury recorded. These results do not support the perception that football injuries are on the rise. Under reporting is a significant concern as players may fear disqualification or that they are evaluated by the coaching staff based on their medical history. More research is needed to confirm lifetime injury prevalence and evaluate differences over time among football players.     

Upper extremity injuries in Danish children aged 6–12, mechanisms,and risk factors

Although injuries to the upper extremity are most costly, the picture of the upper extremity injury problem remains incomplete. This study is the first to describe the etiology and mechanisms of upper extremity injuries in Danish children. A 2.5‐year observational prospective cohort study was conducted to record upper extremity injuries in 1048 children. Data were weekly collected by sending a text message. A total of 176 upper extremity injuries were reported (128 acute injuries). Of the acute upper extremity injuries, 55% were sprains, 47% occurred in the hand/wrist, and 53% of cases were caused by a fall. When corrected for exposure to physical activity, this resulted in an acute upper extremity injury incidence density of 0.18 per 1000 h of physical activity. The odds of sustaining an upper extremity injury was higher in the older children (HR: 1.84, 95% CI: 1.10–3.09), a tendency was found suggesting that girls are at increased acute upper extremity risk compared to boys (HR: 1.40 95% CI: 0.97–2.04). The findings that most injuries occur after a fall, that injury risk increases over age and that girls seem to be at increased injury risk provides essential information to guide future childhood injury prevention.     

Rescheduling Part 2 of the 11+ reduces injury burden and increases compliance in semi‐professional football

Although the 11+ program has been shown to reduce injuries in sub‐elite football, program compliance is typically poor, suggesting that strategies to optimize delivery are necessary. This study investigated the effect of rescheduling Part 2 of the three‐part 11+ program on program effectiveness. Twenty‐five semi‐professional football clubs were randomly allocated to either a Standard‐11+ (n = 398 players) or P2_post group (n = 408 players). Both groups performed the 11+ program at least twice a week throughout the 2017 football season. The Standard‐11+ group performed the entire 11+ program before training activities commenced, whereas the P2_post group performed Parts 1 and 3 of the 11+ program before and Part 2 after training. Injuries, exposure, and individual player 11+ dose were monitored throughout the season. No significant between group difference in injury incidence rate (P2_post vs Standard‐11+ = 11.8 vs 12.3 injuries/1000 h) was observed. Severe time loss injuries > 28 days (33 vs 58 injuries; P < .002) and total days lost to injury (4303 vs 5815 days; P < .001) were lower in the P2_post group. A higher 11+ program dose was observed in the P2_post (29.1 doses; 95% CI 27.9‐30.1) versus Standard‐11+ group (18.9 doses; 95% CI 17.6?20.2; P < .001). In semi‐professional football, rescheduling Part 2 of the 11+ program to the end of training maintained the effectiveness of the original 11+ program to reduce injury incidence. Importantly, rescheduling Part 2 improved player compliance and reduced the number of severe injuries and total injury burden, thereby enhancing effectiveness of the 11+ program.     

Risk for injury when playing in a national football team

The Swedish male senior national football team was followed prospectively between 1991 and 1997. During these 6 years, the team played 73 official matches and had three training camps. The senior author (J. E.) attended 57 of these matches and the three training camps and these matches and training camps, are included in the present study. Exposure to football was recorded individually for each player. The team physician examined all injuries. Total exposure was 7245 h (6235 training and 1010 match hours) and there were 71 injuries (40 training and 31 match injuries). Five (16%) of the match injuries were major, with more than 4 weeks of absence from football. The injury incidence during training was 6.5/1000 h and the injury risk during matchplay was 30.3/1000 h. A significantly higher injury incidence was found for matches lost compared to matches won or drawn (52.5 vs. 22.7/1000 h, P=0.026). No statistically significant difference for injury was found between competitive matches and friendly matches. No difference was found between home and away matches or matches on neutral ground. The risk for injury when playing in a national team compares with previously reported figures for professional football at a high level.     

Involving research‐invested clinicians in data collection affects injury incidence in youth football

It is well established that differences in injury definition and recording methodology restrict comparisons between injury surveillance programmes. There is, however, little documentation of the variation that can exist between data recorders. The aim of this study was, therefore, to explore the effect on reported injuries when team recorders or supervisors are involved in research. Injury data collected prospectively over five seasons for the U16, U17, and U18 age groups in a youth football (soccer) academy were used to compare different recording settings based on the research involvement of the clinicians. A research‐invested team physiotherapist reported an 8.8 times greater incidence (P < 0.001) of non‐time‐loss injuries and a 2.5 times greater incidence (P < 0.001) of minimal injuries (1‐3 days lost) compared to a setting where neither the team physiotherapists nor the supervisor relied on the collected data for research purposes. When team physiotherapists were not invested in research themselves but were supervised by a researcher, the incidence of non‐time‐loss injuries and minimal injuries was 2.5 times (P < 0.001) and 2.0 times greater (P < 0.01) than in the non‐invested setting, respectively. However, there were no differences between recording settings for overall incidence of time‐loss injuries. The results from this study demonstrate that involving clinicians that are relying on the collected data for research purposes can significantly affect the reported rates of non‐time‐loss and minimal injuries. Time‐loss injuries overall were not affected by research investment, and should therefore be preferred for comparisons between teams and seasons.     

Knee function among elite handball and football players 1‐6 years after anterior cruciate ligament injury

The aim of the study was to describe objective and self‐reported knee function for athletes who have returned to elite handball and football play after an ACL injury, comparing these to non‐injured players at the same level. A total of 414 handball and 444 football players completed baseline tests from 2007 through 2014, examining lower extremity strength, dynamic balance, knee laxity, and knee function (KOOS questionnaire). Measures were compared between injured and non‐injured legs and between injured legs and legs of controls. Eighty (9.3%) of the 858 players reported a previous ACL injury, 1‐6 years post‐injury (3.5±2.5 years), 49 handball (61.3%) and 31 football players (38.7%). We found no difference in strength or dynamic balance between previously ACL‐injured (N=80) and non‐injured players legs (N=1556). However, lower quadriceps (6.3%, 95% CI: 3.2‐9.2) and hamstrings muscle strength (6.1%, 95% CI: 3.3‐8.1) were observed in previously ACL‐injured legs compared to the non‐injured contralateral side (N=80). ACL‐injured knees displayed greater joint laxity than the contralateral knee (N=80, 17%, 95% CI: 8‐26) and healthy knees (N=1556, 23%, 95% CI: 14‐33). KOOS scores were significantly lower for injured knees compared to knees of non‐injured players. ACL‐injured players who have successfully returned to elite sport have comparable strength and balance measures as their non‐injured teammates. Subjective perception of knee function is strongly affected by injury history, with clinically relevant lower scores for the KOOS subscores Pain, Function, Sport, and Quality Of Life.     

Risk factors for injury in middle school football players

BACKGROUND: Little is known about the frequency of or risk factors for injuries in middle school or junior high school football players. PURPOSE: To examine the associations of player characteristics (injury history, conditioning, player position, special equipment) and physical parameters (body mass index, weight, height, grip strength) with risk of injury. STUDY DESIGN: Prospective cohort study. METHODS: We documented risk factors for injury in 646 middle school football players, 10 to 15 years of age, in the Oklahoma City, Oklahoma, school district during the 1998 and 1999 seasons. Player characteristics and physical parameters were measured at the beginning of both seasons. Logistic regression methods were used to determine whether baseline variables were associated with the odds of subsequent injury. RESULTS: More playing experience was the only variable significantly associated with the risk of injury in multivariate analyses. This association was observed regardless of the type of injury and even after indirectly controlling for time at risk of injury by restricting analyses to first-string players. Increasing age was significantly associated with the risk of fractures. CONCLUSIONS: Results suggest that physical characteristics play a minor role in risk of injury from football in this age group.     

Risk factors for injury in high school football players

BACKGROUND: Many studies have reported the frequency and types of injuries in high school football players. However, few have assessed the relationship between player characteristics and risk of injury. PURPOSE: To describe the epidemiologic characteristics of and risk factors for injury in high school football players and to determine whether players' characteristics could be used to predict subsequent injury. STUDY DESIGN: Prospective cohort study. METHODS: This study was part of a 2-year prospective investigation (1998 to 1999) of risk factors for injury in 717 (343 in the 1998 season and 374 in the 1999 season) high school football players in the Oklahoma City, Oklahoma, School District. Player characteristics (playing experience, position, injury history) and physical parameters (body mass index, weight, height, grip strength) were measured at the beginning of each season. Logistic regression analysis was used to determine whether any of the baseline variables were associated with the odds of subsequent injury. RESULTS: The physical characteristics of players, such as body mass index and strength, were not associated with risk of injury. More playing experience and a history of injury in the previous season were significantly related to increased risk. Linemen were at the highest risk of injury, particularly knee injuries and season-ending injuries. CONCLUSIONS: Future research should focus on decreasing the risk of injury to linemen.     

A comparison of injuries in elite male and female football players: A five‐season prospective study

The aim was to compare the epidemiology of injuries between elite male and female football players from the same club. Injuries and individual exposure time in a male team and a female team, both playing in the Spanish first division, were prospectively recorded by the club's medical staff for five seasons (2010‐2015) following the FIFA consensus statement. Total, training, and match exposure hours per player‐season were 20% higher for men compared to women (P< .01). Total, training, and match injury incidence were 30%‐40% higher in men (P≤ .04) mainly due to a 4.82 (95% confidence interval [CI ] 2.30‐10.08) times higher incidence of contusions, as there were no differences in the incidence of muscle and joint/ligament injuries (P≥ .44). The total number of absence days was 21% larger in women owing to a 5.36 (95% CI 1.11‐25.79) times higher incidence of severe knee and ankle ligament injuries. Hamstring strains and pubalgia cases were 1.93 (95% CI 1.16‐3.20) and 11.10 (95% CI 1.48‐83.44) times more frequent in men, respectively; whereas quadriceps strains, anterior cruciate ligament ruptures, and ankle syndesmosis injuries were 2.25 (95% CI 1.22‐4.17), 4.59 (95% CI 0.93‐22.76), and 5.36 (95% CI 1.11‐25.79) times more common in women, respectively. In conclusion, prevention strategies should be tailored to the needs of male and female football players, with men more predisposed to hamstring strains and hip/groin injuries, and women to quadriceps strains and severe knee and ankle ligament injuries.     

Neuromuscular training reduces lower limb injuries in elite female basketball players. A cluster randomized controlled trial

The study was a two‐armed, parallel group, cluster randomized controlled trial in which 15 teams (160 players) were assigned to either an experimental group (EG , 8 teams n = 86), which warmed‐up with bodyweight neuromuscular exercises, or a control group (CG , 7 teams, n = 74) that performed standard tactical‐technical exercises before training. All injuries during the 2015‐2016 regular season were counted. Epidemiologic incidence proportion and incidence rate were also calculated. Countermovement jump (CMJ ) and composite Y‐Excursion Balance test (YBT ) were used to assess lower limb strength and postural control. A total of 111 injuries were recorded. Chi‐square test detected statistically significant differences between EG and CG (32 vs 79, P  = .006). Significant differences in the injuries sustained in the EG (21 vs 11, P  = .024) and CG (52 vs 27, P  = .0001) during training and matches, respectively, were observed. Significant differences in post‐intervention injuries were observed between in EG and CG during training (21 vs 52, P  < .0001) and matches (11 vs 27, P  = .006). Significant differences in epidemiologic incidence (0.37 vs 1.07, P  = .023) and incidence rate (1.66 vs 4.69, P  = .012) between the EG and the CG were found. Significant improvement in CMJ (+9.4%, P  < .0001; d  = 1.2) and composite YBT (right: +4.4%, P  = .001, d  = 1.0; left: +3.0%, P  = .003; d  = 0.8) for the EG was noted. Significant differences in post‐intervention CMJ (+5.9%, P  = .004) and composite YBT scores (right, +3.7%, P  = .012; left, +2.3%, P  = .007) between the EG and the CG were observed. Including bodyweight neuromuscular training into warm‐up routines reduced the incidence of serious lower limb injuries in elite female basketball players.     

The impact of playing in matches while injured on injury surveillance findings in professional football

This study aimed to analyze the frequency, nature, and consequences of footballers playing matches while injured, and to examine the impact on injury surveillance findings. High levels of inter‐rater reliability and content validity were established for a tool designed to document players who were already injured at the start of a match. The tool was implemented in three English football teams (a Championship, League 1, and League 2 team) for one season, using a “time loss” definition of injury. One hundred forty‐three matches were surveyed, revealing 102 match appearances by players who were already injured. Almost half of all games featured at least one injured player, with episodes of playing with injury occurring more frequently and lasting longer in League 2 players compared with higher level players. No association was observed between the number of injured players starting matches and match outcome [χ²(4, N = 143) = 3.27, P = 0.514]. Fifteen percent of all injury episodes captured were only through prospective documentation of playing while injured. The findings show that both traumatic and overuse injuries are managed by footballers through competitive matches, and have important implications for aiding understanding of the epidemiology of injury in professional football.     

Injury epidemiology in a national football team of the Middle East

Many football epidemiological studies have been performed but only two of them have investigated injury risk in a national football team. In the present study, the senior male Qatar national football team was followed prospectively for two seasons. All injuries that were incurred during training and matches were recorded, together with match and training exposure time. Principal findings were (i) a higher injury incidence during matches than during training, (65.9 vs 4.3/1000 h, P<0.001), (ii) a high incidence of muscular strain during matches (23.2/1000 h) and (iii) a greater severity of injury in games than in regular training or camp situations (19.5 vs 8.4 vs 6.7 days, P<0.05). Despite the unique environmental, social and cultural setting in the Middle East, these findings are consistent with previous data from European football, suggesting that international guidelines on injury prevention and management may be applied in this region.     

Exercise program for prevention of groin pain in football players: a cluster‐randomized trial

Groin injuries cause major problems in sports and particularly in football. Exercise is effective in treating adductor‐related groin pain, but no trials have been published regarding the specific prevention of groin pain or prevention specifically targeting overuse injuries in sport using exercise programs. We performed a cluster‐randomized trial including 55 football clubs representing 1211 players. The clubs were randomized to an exercise program aimed at preventing groin injuries (n=27) or to a control group training as usual (n=28). The intervention program consisted of six exercises including strengthening (concentric and eccentric), coordination, and core stability exercises for the muscles related to the pelvis. Physiotherapists assigned to each club registered all groin injuries. Twenty‐two clubs in each group completed the study, represented by 977 players. There was no significant effect of the intervention (HR=0.69, 95% CI 0.40–1.19). The risk of a groin injury was reduced by 31%, but this reduction was not significant. A univariate analysis showed that having had a previous groin injury almost doubles the risk of developing a new groin injury and playing at a higher level almost triples the risk of developing a groin injury.     

A prospective study of injuries in licensed floorball players

Injuries occuring among 457 licensed floorball players in teh Swedish National League were analysed prospectively during the season from 1993 to 1994. Fifty-one (11%) players sustained 58 injuries. The majority (76%) of the injuries were due to trauma mostly during the game (55%). Twenty-three (52%) of the traumatic injuries were caused by an opponent or a stick. Ankle sprain (35%) was the most common diagnosis. Injury severity classified with regard to time of absence from sport participation were similarly distributed for minor (36%), moderate (29%) and major (35%) injuries. The total rate of injury was 2.5 per 1000 hours for female and 2.6 for male players. Although this rate is lower than for contact sports like soccer and ice-hockey, we feel that further investigation of floorball injuries and improvement of protection devices would be valuable.     

Frequency and associated factors of poor knee alignment in young Brazilian volleyball players

Objectives: Poor knee alignment during the deceleration phase of closed kinetic chain movements, such as landings, is a relevant risk factor for injuries in sports. This study assessed the knee alignment and possible associated factors in young Brazilian volleyball athletes

Methods: One hundred and seventeen athletes of both genders (9–19 years old) were assessed during a drop jump for the observation of knee alignment. Chi-square test was used to describe the association between poor knee alignment and: gender, age category (≤14 years and ≥15 years), sports experience, participation in competitions, the presence of knee pain during training, and history of lower limb injury

Results: Seventy percent of athletes presented poor knee alignment, which was slightly associated with a sports experience lower than one year.

Conclusion: Thus, considering the high number of volleyball practitioners and its strong presence in physical education classes, preventive measures should be adopted for young volleyball athletes of both genders, especially in the sports initiation phase.     

Acute hamstring injuries in Danish elite football: A 12‐month prospective registration study among 374 players

The purpose of the present study was to examine the incidence rates of acute hamstring injuries in Danish elite football sustained during training or match play. Furthermore, it was our intention to document details about the recurrence, severity and the injury seasonal distribution. Hamstring injuries among 374 elite football players were registered prospectively during a 12‐month period. A total of 46 first‐time and eight recurrent hamstring injuries were registered. The incidence rates for incurring a first‐time hamstring injury showed a significantly (P<0.01) greater incidence rate per 1000 h during match play compared with training. Of 32 players who reported a hamstring injury in the 12‐month period before the study, eight (25%) incurred an injury that fulfilled the criteria for a recurrent injury. In 69% of the injuries, the severity of injury was categorized as moderate (8–28 days from injury to injury free) and 18% as severe (>28 days from injury to injury free). Each team sustained a mean of 3.4 hamstring injuries per season, with a mean of 21.5 days missed per injury (range 3–136; median 16 days per injury). The seasonal distribution showed an accumulation of injuries in the first 2 months after a 3.5‐month mid‐season winter break.