Injuries in women's professional soccer

The epidemiology of sports-related fractures in adolescents

OBJECTIVE

To examine the epidemiology of sports-related fractures in adolescents aged 10-19 years.

METHODS

All fractures in adolescents presenting to the Royal Hospital for Sick Children and the Royal Infirmary of Edinburgh in a one-year period were prospectively documented and all sports-related fractures retrospectively examined. These two hospitals have a defined population facilitating epidemiological studies.

RESULTS

There were 408 adolescent sports-related fractures giving an overall incidence of 5.63/1000/year. The gender ratio was 87/13% male/female and 84% were upper limb fractures. Thirty sports produced 22 different fracture types. Football, rugby and skiing accounted for 66.2% of the fractures. The commonest fractures were in the finger phalanges (28.7%), distal radius and ulna (23.0%) and metacarpus (12.7%).

CONCLUSIONS

Sport-related fractures are common in adolescents, particularly in males. They tend to be low-energy injuries affecting the upper limb in particular. Few require operative treatment although their frequency means that they impose significant demands on orthopaedic surgeons and health systems.

Injuries in women's soccer: a 1-year all players prospective field study of the women's Bundesliga (German premier league)

OBJECTIVE

To obtain precise information on injury patterns in the women's premier soccer league in Germany.

DESIGN

One-year, prospective, epidemiologic cohort study.

SETTING

Institutional level German Football Association.

PARTICIPANTS

All 254 players from all 12 women's premier league teams were included.

INTERVENTIONS

Base information by standardized personal interviews. Evaluation of all injury-associated medical data transmitted by standardized documentation forms.

ASSESSMENT OF RISK FACTORS

Injuries incidence rates (average, 95% confidence intervals) based on the exposure in matches and at practice.

MAIN OUTCOME MEASURES

All time loss diagnoses, number and context of injuries related to their anatomical localization, severity, and rehabilitation period were recorded.

RESULTS

All 254 players finished the study [average age, 22.8 years (16-35 years)]. Two hundred forty-six injuries amounted to an injury rate of 3.3 per 1000 hours (games, 18.5 per 1000 hours; practice, 1.4 per 1000 hours). Injury distribution: knee, 31.0%; ankle, 22.1%; thigh, 12.9%; and head, 7.1%. The seasonal peak was at the beginning of the competitive season. Injury rates doubled after the 60th minute. Twenty-nine percent of the injuries were severe, and 37% were moderate.

CONCLUSIONS

Female players suffer a high amount of head injuries and severe knee and ankle injuries. The most common single injury is a sprained ankle. Torn ligaments in the ankle and knee are the most common injuries that require a long recovery period. Most of the severe injuries (>30 days) are due to noncontact intrinsic mechanisms. Almost one-quarter of all injuries consist of exertion syndromes not yet correlated with certain seasonal periods.

[Knee and ankle injuries from playing football]

Soccer is the most common sport activity worldwide. Over the last two decades the increase in soccer players has mainly been due to increased interest by females. In general, soccer is a relatively safe sport activity, especially if minor injuries resulting in short periods of absence from playing or training are neglected. However, due to the high number of soccer players severe injuries are also frequent. These are a problem not only for the injured player and the team but may also become problematic for the socio-economic system. In up to 80-90% structures of the lower extremities are injured. For sufficient radiological diagnosis knowledge of the biomechanics of the soccer game and some details about the history of the injury may be of help. To prevent soccer injuries or keep the degree of injury low, special programs had been developed.

Hamstring activation during lower body resistance training exercises

PURPOSE

The purpose of this study was to evaluate differences in hamstring activation during lower body resistance training exercises. This study also sought to assess differences in hamstring-to-quadriceps muscle activation ratios and gender differences therein.

METHODS

A randomized repeated measures design was used to compare six resistance training exercises that are commonly believed to train the hamstrings, including the squat, seated leg curl, stiff leg dead lift, single leg stiff leg dead lift, good morning, and Russian curl. Subjects included 34 college athletes. Outcome measures included the biceps femoris (H) and rectus femoris (Q) electromyography (EMG) and the H-to-Q EMG ratio, for each exercise.

RESULTS

Main effects were found for the H (P < 0.001) and Q (P < 0.001). Post hoc analysis identified the specific differences between exercises. In addition, main effects were found for the H-to-Q ratio when analyzed for all subjects (P < 0.001). Further analysis revealed that women achieved between 53.9 to 89.5% of the H-to-Q activation ratios of men, for the exercises assessed. In a separate analysis of strength matched women and men, women achieved between 35.9 to 76.0% of the H-to-Q ratios of men, for these exercises.

CONCLUSIONS

Hamstring resistance training exercises offer differing degrees of H and Q activation and ratios. Women compared with men, are less able to activate the hamstrings and/or more able to activate the quadriceps. Women may require disproportionately greater training for the hamstrings compared with the quadriceps.

Injuries among male and female elite football players

All 12 female football clubs (228 players) and 11 of 14 male clubs (239 players) in the Swedish premier league were followed prospectively during the 2005 season. Individual exposure (playing time), injuries (time loss), and injury severity (days lost due to injury) were recorded by the team medical staffs. Injury incidence was higher for male players during both training (4.7 vs 3.8 injuries/1000 h, P=0.018) and match play (28.1 vs 16.1, P<0.001). However, no difference was found in the incidence of severe injury (absence >4 weeks) (0.7/1000 h in both groups). The thigh, especially the hamstrings, was the overall most commonly injured region in both sexes, while the hip/groin was more commonly injured in male players and the knee in female players. Knee ligament injuries accounted for 31% and 37% of the total time lost from football for male and female players, respectively. In conclusion, male elite players had a higher injury incidence than their female counterparts although no difference was observed in the incidence of moderate to severe injury. We recommend that preventive measures should be focused on hamstring and knee ligament injury in order to reduce the overall injury burden.

Preventing knee injuries in adolescent female football players - design of a cluster randomized controlled trial [NCT00894595]

Background

Knee injuries in football are common regardless of age, gender or playing level, but adolescent females seem to have the highest risk. The consequences after severe knee injury, for example anterior cruciate ligament (ACL) injury, are well-known, but less is known about knee injury prevention. We have designed a cluster randomized controlled trial (RCT) to evaluate the effect of a warm-up program aimed at preventing acute knee injury in adolescent female football.

Methods

In this cluster randomized trial 516 teams (309 clusters) in eight regional football districts in Sweden with female players aged 13–17 years were randomized into an intervention group (260 teams) or a control group (256 teams). The teams in the intervention group were instructed to do a structured warm-up program at two training sessions per week throughout the 2009 competitive season (April to October) and those in the control group were informed to train and play as usual. Sixty-eight sports physical therapists are assigned to the clubs to assist both groups in data collection and to examine the players' acute knee injuries during the study period. Three different forms are used in the trial: (1) baseline player data form collected at the start of the trial, (2) computer-based registration form collected every month, on which one of the coaches/team leaders documents individual player exposure, and (3) injury report form on which the study therapists report acute knee injuries resulting in time loss from training or match play. The primary outcome is the incidence of ACL injury and the secondary outcomes are the incidence of any acute knee injury (except contusion) and incidence of severe knee injury (defined as injury resulting in absence of more than 4 weeks). Outcome measures are assessed after the end of the 2009 season.

Discussion

Prevention of knee injury is beneficial for players, clubs, insurance companies, and society. If the warm-up program is proven to be effective in reducing the incidence of knee injury, it can have a major impact by reducing the future knee injury burden in female football as well as the negative long-term disabilities associated with knee injury.

Trial registration

NCT00894595

Foot and ankle injuries during the Athens 2004 Olympic Games

Background

Major, rare and complex incidents can occur at any mass-gathering sporting event and team medical staff should be appropriately prepared for these. One such event, the Athens Olympic Games in 2004, presented a significant sporting and medical challenge. This study concerns an epidemiological analysis of foot and ankle injuries during the Games.

Methods

An observational, epidemiological survey was used to analyse injuries in all sport tournaments (men's and women's) over the period of the Games.

Results

A total of 624 injuries (525 soft tissue injuries and 99 bony injuries) were reported. The most frequent diagnoses were contusions, sprains, fractures, dislocations and lacerations. Significantly more injuries in male (58%) versus female athletes (42%) were recorded. The incidence, diagnosis and cause of injuries differed substantially between the team sports.

Conclusion

Our experience from the Athens Olympic Games will inform the development of public health surveillance systems for future Olympic Games, as well as other similar mass events.

Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial

OBJECTIVE

To examine the effect of a comprehensive warm-up programme designed to reduce the risk of injuries in female youth football.

DESIGN

Cluster randomised controlled trial with clubs as the unit of randomisation.

SETTING

125 football clubs from the south, east, and middle of Norway (65 clusters in the intervention group; 60 in the control group) followed for one league season (eight months).

PARTICIPANTS

1892 female players aged 13-17 (1055 players in the intervention group; 837 players in the control group).

INTERVENTION

A comprehensive warm-up programme to improve strength, awareness, and neuromuscular control during static and dynamic movements.

MAIN OUTCOME MEASURE

Injuries to the lower extremity (foot, ankle, lower leg, knee, thigh, groin, and hip).

RESULTS

During one season, 264 players had relevant injuries: 121 players in the intervention group and 143 in the control group (rate ratio 0.71, 95% confidence interval 0.49 to 1.03). In the intervention group there was a significantly lower risk of injuries overall (0.68, 0.48 to 0.98), overuse injuries (0.47, 0.26 to 0.85), and severe injuries (0.55, 0.36 to 0.83).

CONCLUSION

Though the primary outcome of reduction in lower extremity injury did not reach significance, the risk of severe injuries, overuse injuries, and injuries overall was reduced. This indicates that a structured warm-up programme can prevent injuries in young female football players.

TRIAL REGISTRATION

ISRCTN10306290.

The H-Wave((R)) Device Induces NODependent Augmented Microcirculation and Angiogenesis, Providing Both Analgesia and Tissue Healing in Sports Injuries

The hypothesis that the H-Wave(R) device (Electronic Waveform Lab, Inc., Huntington Beach, CA), a small-diameter fiber stimulator, is a paradigm shift of electrotherapeutic treatment of pain associated with human neuropathies and sports injuries is based on a number of its properties. The primary effect of H-Wave(R) device stimulation (HWDS) is the stimulation of "red-slow-twitch" skeletal muscle fibers. The authors propose, based on the unique waveform, that the H-Wave(R) device specifically and directly stimulates the small smooth muscle fibers within the lymphatic vessels ultimately leading to fluid shifts and reduced edema. In unpublished rat studies, it has been observed that HWDS induces protein clearance. The H-Wave(R) device was designed to stimulate an ultra low frequency (1-2 Hz), low tension, nontetanizing, and nonfatiguing contraction, which closely mimics voluntary or natural muscle contractions. The H-Wave(R) device can stimulate small fibers due in part to its exponentially decaying waveform and constant current generator activity. The main advantage of these technologies over currently applied electrical stimulators (eg, transcutaneous electrical nerve stimulator [TENS], interferential [IF], neuromuscular electrical stimulation [NMES], high-volt galvanic, etc.) is that H-Wave\'s(R) small fiber contraction does not trigger an activation of the motor nerves of the large white muscle fibers or the sensory delta and C pain nerve fibers, thus eliminating the negative and painful effects of tetanizing fatigue, which reduces transcapillary fluid shifts. Another function of the H-Wave(R) device is an anesthetic effect on pain conditions, unlike a TENS unit which in the short term activates a hypersensory overload effect (gate theory) to stop pain signals from reaching the thalamic region of the brain. When the H-Wave(R) device is used at high frequency (60 Hz), it acts intrinsically on the nerve to deactivate the sodium pump within the nerve fiber, leading to a long-lasting anesthetic/analgesic effect due to an accumulative postsynaptic depression. Moreover, HWDS produces a nitric oxide (NO)-dependent enhancement of microcirculation and angiogenesis in rats. Thus, the authors hypothesize that because of these innate properties of the H-Wave(R) device, it may provide a paradigm shift for the treatment of both short- and long-term inflammatory conditions associated with pain due to sports injuries. A recent meta-analysis found a moderate-to-strong effect of the H-Wave(R) device in providing pain relief, reducing the requirement for pain medication, and increasing functionality. The most robust effect was observed for improved functionality, suggesting that the H-Wave(R) device may facilitate a quicker return to the field.

KEYWORDS

H-Wave(R) device; sportsmedicine, nitric oxide-dependent blood flow; analgesia; angiogenesis.

The epidemiology of acute sports-related fractures in adults

OBJECTIVE

To determine the incidence and epidemiology of acute sports-related fractures in adults.

DESIGN

Retrospective analysis of a prospectively collected database containing all in-patient and out-patient fractures in a defined patient population in 2000.

SETTING

Orthopaedic Trauma Unit.

RESULTS

There were 5953 fractures in 2000 of which 761 (12.8%) were caused in sporting accidents. The overall incidence was 142/10(5) with 261/10(5) in males and 35/10(5) in females. The mean age was 25.6 years. 41 sports caused the fractures but 10 sports accounted for 86.8% of fractures. In 40 sports the highest prevalence of fractures were in the upper limb and the commonest fractures seen were in the distal radius, metacarpus and finger phalanges although the highest prevalence was in the clavicle. Sports fractures comprised 16.5% of upper limb fractures and 7.5% of lower limb fractures. Our results suggest that there are 80,000-85,000 sports fractures annually in the United Kingdom of which about 18,000 require operative treatment.

CONCLUSIONS

Sporting activities are the third most common cause of fractures. With increasing affluence it is likely that they will increase. Fractures of the wrist and hand are the most common but in some sports there are a number of higher energy fractures. Our results suggest that, even in sport, there are a number of osteoporotic fractures usually occurring in women.

The epidemiology of United States high school soccer injuries, 2005-2007

BACKGROUND

United States high school soccer participation increased 5 fold over the last 30 years. With increased participation comes increased injury incidence.

HYPOTHESIS

High school soccer injury patterns will vary by gender and type of exposure.

STUDY DESIGN

Descriptive epidemiologic study.

METHODS

Soccer-related injury data were collected over the 2005-2006 and 2006-2007 school years from 100 nationally representative United States high schools via Reporting Information Online (RIO, an Internet-based sports-related injury surveillance system).

RESULTS

Participating certified athletic trainers reported 1524 soccer injuries during 637 446 athlete exposures (AEs), for an injury rate of 2.39 per 1000 AEs, corresponding to a nationally estimated 807 492 soccer-related injuries during the 2005-2006 and 2006-2007 seasons. The injury rate per 1000 AEs was greater during competition (4.77) than practice (1.37) (rate ratio [RR] = 3.49; 95% confidence interval [CI], 3.15-3.87). Overall, the most frequent diagnoses were incomplete ligament sprains (26.8%), incomplete muscle strains (17.9%), contusions (13.8%), and concussions (10.8%). The most commonly injured body sites were the ankle (23.4%), knee (18.7%), head/face (13.7%), and thigh/upper leg (13.1%). Similar proportions of boys (57.9%) and girls (53.9%) returned to activity in <1 week. During competition, girls sustained complete knee ligament sprains requiring surgery at a rate of 26.4 per 100 000 AEs, higher than the rate among boys during competition (1.98 per 100 000 AEs) (RR = 13.3; 95% CI, 3.15-56.35) and among girls during practice (2.34 per 100 000 AEs) (RR = 11.3; 95% CI, 4.31-29.58). Player-to-player contact was more common among competition injuries (injury proportion ratio [IPR] = 2.42; 95% CI, 2.01-2.92), while noncontact mechanisms were more common among practice injuries (IPR = 2.39; 95% CI, 1.90-3.01).

CONCLUSIONS

High school soccer injury patterns vary by gender and type of exposure. Identifying such differences in injury patterns is the important first step in the development of evidence-based, targeted injury prevention efforts.

Self-reported injury history and lower limb function as risk factors for injuries in female youth soccer

BACKGROUND

Identifying and understanding injury risk factors are necessary to develop and target measures to prevent injuries. Because youth teams rarely have health care professionals working directly with the team, identifying players at increased risk through elaborate clinical tests is not feasible. Questionnaires may be a possible alternative as screening instruments.

PURPOSE

To examine whether injury history and lower limb function assessed by a self-administered questionnaire represent risk factors for injury.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

At baseline, female soccer players (aged 14-16 years) were asked to complete a detailed questionnaire covering sports participation; history of previous injuries to the ankle, knee, hamstring, or groin; as well as present function of these 4 specific regions. A total of 1430 (71% of the entire cohort) were followed up to record injuries during the subsequent 8 months.

RESULTS

A history of a previous injury to the ankle (rate ratio, 1.2 [1.1-1.3]; P < .001), knee (rate ratio, 1.4 [1.2-1.6]; P <.001), or groin (rate ratio, 1.6 [1.2-2.1]; P = .004) increased the risk of new injuries to the same region. Reporting a reduced function (defined as <80% of the maximum score) for the ankle (rate ratio, 1.7 [1.1-2.7]; P =.021) or knee (rate ratio, 3.2 [1.8-5.7]; P <.001) was also a significant risk factor. However, the sensitivity of previous injuries and lower limb function in predicting new injuries was low.

CONCLUSION

A history of previous injury and reduced function at baseline were significant risk factors for new injuries to the same region during the following season.

Injuries in Norwegian female elite soccer: a prospective one-season cohort study

Female soccer has become increasingly popular during the last two decades. According to the International Football Association (FIFA) there are approximately 40 million registered female soccer players in the world. Three studies in elite soccer have shown an injury incidence during games ranging from 12.6 to 23.3 injuries per 1,000 h. A very high incidence of ACL-injuries ranging from 0.31 to 2.2 per 1,000 game hours has also been shown. We followed the Norwegian female elite series during the 2001 season to estimate the incidence and characteristics of injuries. A total of 181 female soccer players on ten teams were followed during the 2001 elite season in Norway. We recorded baseline data, match and training exposure and injury data as type of injury, location and severity of injury. The mean age of the players was 23 years (range 17-34). A total of 189 injuries were recorded and 19 (10%) of these were overuse injuries; 89 (47%) occurred during games and 100 (53%) during training sessions. The incidence of acute injuries was 23.6 per 1,000 game hours and 3.1 per 1,000 training hours. The majority of the injuries occurred in the lower extremities (81%), but there were also a significant number of head injuries (6.3%). The most common injury type was ankle sprain (17.2%). Half of the injuries were minor, with training or game absence of less than 7 days. Midfielders sustained the most injuries (32.6%) with an incidence of 42.4 per 1,000 game hours. We recorded two ACL-injuries and two PCL-injuries during the season. They all occurred during games, and the incidence was therefore calculated to 0.6 per 1,000 game hours for both injury types. The incidences of injuries reported for female soccer varies considerably, with the highest numbers reported from Germany and the present study. These studies have also the highest incidence of minor injuries registered. The location of the injuries is quite similar compared to other reports, but the number of ankle sprains seems to be higher in our study, whereas the number of knee and thigh injuries is lower. There has been much attention to ACL injuries in team handball and hamstring injuries in soccer in Norway, and this could have influenced the team's pre-season training, resulting in a reduction in the incidence of these injury types. The high number of ankle injuries has to be addressed to see whether this is a result of inadequate rehabilitation routines leading to re-injuries, or other factors. The high number of ACL-injuries in these reports is alarming and needs special attention in the future.

Injuries in young elite female soccer players: an 8-season prospective study

BACKGROUND

Epidemiologic data on injuries in young female soccer players at elite levels are scarce.

PURPOSE

The aim of the present study is to investigate the incidence of soccer-related injuries in young elite female French players.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Injuries sustained by players between 15 and 19 years of age, during 8 seasons, were diagnosed and documented by a sports physician according to type, location, severity, the date the injury occurred, and playing position.

RESULTS

Altogether 619 injuries were documented for 110 players (92.4%). Of these injuries, 64.6% (4.6/1000 training hours; 95% confidence interval [CI], 4.2-5.0) and 35.4% (22.4/1000 match hours; 95% CI, 19.4-25.4) were sustained during training and matches, respectively. The risk of injury was greater in the youngest (under age 15) group compared with the oldest (under 19) group (relative risk 1.7; 95% CI, 1.3-2.3). Traumatic injuries amounted to 536 (86.4%) and 83 (13.4%) were overuse injuries. There were 51.9% minor injuries, 35.7% moderate injuries, and 12.4% major injuries. Most injuries were located at the lower extremities (83.4%), with the majority affecting the ankle (n = 157). The most commonly diagnosed injury was ankle sprain (16.8%). Twelve anterior cruciate ligament ruptures were sustained, with the majority occurring during matches (n = 10; 1.0/1000 match hours; 95% CI, 0.4-1.6). Reinjuries accounted for 4.4% of total injuries, and September was the predominant month for injury (14.2%).

CONCLUSIONS

The results, when compared with those of other investigations on female soccer players, revealed high rates of both traumatic injury and match injury, whereas recurrence of injury was low. Injuries, notably sprains, to the ankle were common, suggesting a need for the implementation of specific injury prevention strategies for this joint.

Preventing injuries in female youth football--a cluster-randomized controlled trial

A set of exercises--the "11"--have been selected to prevent football injuries. The purpose of this cluster-randomized controlled trial was to investigate the effect of the "11" on injury risk in female youth football. Teams were randomized to an intervention (n=59 teams, 1091 players) or a control group (n=54 teams, 1001 players). The intervention group was taught the "11," exercises for core stability, lower extremity strength, neuromuscular control and agility, to be used as a 15-min warm-up program for football training over an 8-month season. A total of 396 players (20%) sustained 483 injuries. No difference was observed in the overall injury rate between the intervention (3.6 injuries/1000 h, confidence interval (CI) 3.2-4.1) and control group (3.7, CI 3.2-4.1; RR=1.0, CI 0.8-1.2; P=0.94) nor in the incidence for any type of injury. During the first 4 months of the season, the training program was used during 60% of the football training sessions, but only 14 out of 58 intervention teams completed more than 20 prevention training sessions. In conclusion, we observed no effect of the injury prevention program on the injury rate, most likely because the compliance with the program was low.

Football injuries during European Championships 2004-2005

The risk of injury in football is high, but few studies have compared men's and women's football injuries. The purpose of this prospective study was to analyse the exposure and injury characteristics of European Championships in football and to compare data for men, women and male youth players. The national teams of all 32 countries (672 players) that qualified to the men's European Championship 2004, the women's European Championship 2005 and the men's Under-19 European Championship 2005 were studied. Individual training and match exposure was documented during the tournaments as well as time loss injuries. The overall injury incidence was 14 times higher during match play than during training (34.6 vs. 2.4 injuries per 1000 h, P < 0.0001). There were no differences in match and training injury incidences between the championships. Teams eliminated in the women's championship had a significantly higher match injury incidence compared to teams going to the semi-finals (65.4 vs. 5.0 injuries per 1000 h, P = 0.02). Non-contact mechanisms were ascribed for 41% of the match injuries. One-fifth of all injuries were severe with absence from play longer than 4 weeks. In conclusion, injury incidences during the European Championships studied were very similar and it seems thus that the risk of injury in international football is at least not higher in women than in men. The teams eliminated in the women's championship had a significantly higher match injury incidence than the teams going to the final stage. Finally, the high frequency of non-contact injury is worrying from a prevention perspective and should be addressed in future studies.

Tackle mechanisms and match characteristics in women's elite football tournaments

BACKGROUND

Several tools have been used for assessing risk situations and for gathering tackle information from international football matches for men but not for women.

PURPOSE

To analyse activities in women's football and to identify the characteristics and risk potentials of tackles.

STUDY DESIGN

Retrospective video analysis.

METHOD

Video recordings of 24 representative matches from six women's top-level tournaments were analysed for tackle parameters and their risk potential.

RESULTS

3531 tackles were recorded. Tackles in which the tackling player came from the side and stayed on her feet accounted for nearly half of all challenges for the ball in which body contact occurred. 2.7% of all tackles were classified as risk situations, with sliding-in tackles from behind and the side having the highest risk potential. Match referees sanctioned sliding-in tackles more often than other tackles (20% v 17%, respectively). Tackle parameters did not change in the duration of a match; however, there was an increase in the number of injury risk situations and foul plays towards the end of each half.

CONCLUSIONS

Match properties provide valuable information for a better understanding of injury situations in football. Staying on feet and jumping vertically tackle actions leading to injury were sanctioned significantly more times by the referee than those not leading to injury (p<0.001), but no such difference was seen for sliding-in tackles (previously reported to have the highest injury potential in women's football). Therefore, either the laws of the game are not adequate or match referees in women's football are not able to distinguish between sliding-in tackles leading to and those not leading to injury.

Injuries in female football players in top-level international tournaments

BACKGROUND

Despite the growing popularity of women's football and the increasing number of female players, there has been little research on injuries sustained by female football players.

PURPOSE

Analysis of the incidence, characteristics and circumstances of injury in elite female football players in top-level international tournaments.

STUDY DESIGN

Prospective survey.

METHODS

Injuries incurred in seven international football tournaments were analysed using an established injury report system. Doctors of all participating teams reported all injuries after each match on a standardised injury reporting form. The mean response rate was 95%.

RESULTS

387 injuries were reported from 174 matches, equivalent to an incidence of 67.4 injuries/1000 player hours (95% CI 60.7 to 74.1) or 2.2 injuries/match (95% CI 2.0 to 2.4). Most injuries (84%; 317/378) were caused by contact with another player. The injuries most commonly involved the lower extremity (n = 248; 65%), followed by injuries of the head and neck (n = 67, 18%), trunk (n = 33, 9%) and upper extremity (n = 32, 8%). Contusions (n = 166; 45%) were the most frequent type of injury, followed by sprains or ligament rupture (n = 96; 26%) and strains or muscle fibre ruptures (n = 31; 8%). The most common diagnosis was an ankle sprain. There were 7 ligament ruptures and 15 sprains of the knee. On average 1 injury/match (95% CI 0.8 to 1.2) was expected to result in absence from a match or training.

CONCLUSION

The injury rate in women's top-level tournaments was within the range reported previously for match injuries in elite male and female players. However, the diagnoses and mechanisms of injury among the female players differed substantially from those previously reported in male football players.

Stress fracture risk factors in female football players and their clinical implications

A stress fracture represents the inability of the skeleton to withstand repetitive bouts of mechanical loading, which results in structural fatigue, and resultant signs and symptoms of localised pain and tenderness. Reports of stress fractures in female football players are not prevalent; however, they are probably under-reported and their importance lies in the morbidity that they cause in terms of time lost from participation. By considering risk factors for stress fractures in female football players it may be possible to reduce the impact of these troublesome injuries. Risk factors for stress fractures in female football players include intrinsic risk factors such as gender, endocrine, nutritional, physical fitness and neuromusculoskeletal factors, as well as extrinsic risk factors such as training programme, equipment and environmental factors. This paper discusses these risk factors and their implications in terms of developing prevention and management strategies for stress fractures in female football players.

Causation of injuries in female football players in top-level tournaments

BACKGROUND

Analyses of tackle parameters in injury situations have provided valuable information regarding men's football. However, there are no similar data for women's football.

OBJECTIVE

To categorise the tackle mechanisms leading to injury in elite women's football.

STUDY DESIGN

Retrospective video analysis of injury situations.

METHODS

Events associated with all reported injuries during six women's top-level tournaments were analysed on video recordings for tackle parameters.

RESULTS

More than half of all injuries were due to tackles from the side (52%, 103/200), whereas tackles from behind were much less commonly involved in injury situations (11%, 21/200). One-footed (65%, 130/200) and upper body (21%, 42/200) tackle actions were most common. Sliding-in tackles leading to injury were the least likely to be sanctioned by match referees. Tackling players (45%, 90/200) were almost as likely to be injured as the tackled player (55%).

CONCLUSION

The present study found differences between injury mechanisms in women's football and previously published data on men's football. Further research, especially using video analysis, is needed for a better understanding of risk situations in football.

Lower extremity muscle activation and alignment during the soccer instep and side-foot kicks

STUDY DESIGN

Controlled laboratory study.

OBJECTIVES

To quantify phase duration and lower extremity muscle activation and alignment during the most common types of soccer kick-the instep kick and side-foot kick. A second purpose was to test the hypotheses that different patterns of lower extremity muscle activation occur between the 2 types of kicks and between the kicking limb compared to the support limb.

BACKGROUND

Soccer players are at risk for lower extremity injury, especially at the knee. Kicking the soccer ball is an essential, common, and distinctive part of a soccer player's activity that plays a role in soccer player injury. Regaining the ability to kick is also essential for soccer athletes to return to play after injury.

METHODS

Thirteen male soccer players underwent video motion analysis and electromyography (EMG) of 7 muscles in both the kicking and supporting lower extremity (iliacus, gluteus maximus, gluteus medius, vastus lateralis, vastus medialis, hamstrings, gastrocnemius) and 2 additional muscles in the kicking limb only (hip adductors, tibialis anterior). Five instep and 5 side-foot kicks were recorded for each player. Analysis-of-variance models were used to compare EMG activity between type of kicks and between the kicking and nonkicking lower extremity.

RESULTS

Five phases of kicking were identified: (1) preparation, (2) backswing, (3) limb cocking, (4) acceleration, and (5) follow-through. Comparing the kicking limb between the 2 types of kick, significant interaction effects were identified for the hamstrings (P = .02) and the tibialis anterior (P<.01). Greater activation of the kicking limb iliacus (P<.01), gastrocnemius (P<.01), vastus medialis (P = .016), and hip adductors (P<.01) occurred during the instep kick. Significant differences were seen between the kicking limb and the support limb for all muscles during both types of kick.

CONCLUSIONS

Certain lower extremity muscle groups face different demands during the soccer instep kick compared to the soccer side-foot kick. Similarly, the support limb muscles face different demands than the kicking limb during both kicks. Better definition of lower extremity function during kicking provides a basis for improved insight into soccer player performance, injury prevention, and rehabilitation.

The epidemiology of knee injuries in English professional rugby union

BACKGROUND

Detailed injury epidemiology is an invaluable tool for reducing risks associated with sporting injuries. Very little accurate injury surveillance data exist regarding knee injuries in professional rugby.

HYPOTHESES

(1) Knee injuries have a greater impact on the game than injuries to other body locations. (2) Anterior cruciate ligament and medial collateral ligament injuries cause the greatest days absent from training and match play.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Medical personnel prospectively reported time-loss injuries sustained by 546 professional rugby union players from 12 clubs in England over 2 seasons, and the knee injuries were evaluated.

RESULTS

Injuries to the knee accounted for the highest number of days absent due to injury (7776 days, 21%) and were characteristically severe, with a disproportionately high number of days missed per injury (37 days). Anterior cruciate ligament injuries accounted for the greatest proportion of days missed of all knee injuries (29%), followed by medial collateral ligament injuries (25%). Most severe injuries occurred during contact, mostly during a tackle, and most commonly in the final 20 minutes of a match. Injuries tended to be more common in backs. Injuries sustained during training accounted for 16% of all knee injuries. Each club studied had a mean of 10 knee injuries per season resulting in a total of 353 days absent.

CONCLUSIONS

The incidence of knee injuries sustained during matches was higher than that reported in all other football codes, surpassed only by rugby union at the international level. Knee injuries accounted for the highest player absence due to injury; 5% of an average playing squad were absent at any one time due to knee injuries.

A systematic review on ankle injury and ankle sprain in sports

This article systematically reviews epidemiological studies on sports injury from 1977 to 2005 in which ankle injury was included. A total of 227 studies reporting injury pattern in 70 sports from 38 countries were included. A total of 201,600 patients were included, with 32,509 ankle injuries. Ankle injury information was available from 14,098 patients, with 11 847 ankle sprains. Results show that the ankle was the most common injured body site in 24 of 70 included sports, especially in aeroball, wall climbing, indoor volleyball, mountaineering, netball and field events in track and field. Ankle sprain was the major ankle injury in 33 of 43 sports, especially in Australian football, field hockey, handball, orienteering, scooter and squash. In sports injuries throughout the countries studied, the ankle was the second most common injured body site after the knee, and ankle sprain was the most common type of ankle injury. The incidence of ankle injury and ankle sprain was high in court games and team sports, such as rugby, soccer, volleyball, handball and basketball. This systematic review provides a summary of the epidemiology of ankle injury in sports.

Epidemiology of 1.6 million pediatric soccer-related injuries presenting to US emergency departments from 1990 to 2003

BACKGROUND

As soccer participation in the United States increases, so does the number of children at risk for injury.

PURPOSE

To examine pediatric soccer-related injuries presenting to US emergency departments from 1990 to 2003.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

A descriptive analysis of nationally representative, pediatric, soccer-related injury data from the US Consumer Product Safety Commission's National Electronic Injury Surveillance System.

RESULTS

Among those 2 to 18 years of age, a nationally estimated 1597528 soccer-related injuries presented to US emergency departments from 1990 to 2003. Mean age was 13.2 years (range, 2-18 years); 58.6% were male. From 1990 to 2003, there was an increase in the absolute number of injuries among girls (P < .0001). The wrist/finger/hand (20.3%), ankle (18.2%), and knee (11.4%) were the most commonly injured body parts. The most common diagnoses were sprain/strain (35.9%), contusion/abrasion (24.1%), and fracture (23.2%). Boys were more likely to have face and head/neck injuries (17.7%; relative risk, 1.40; 95% confidence interval, 1.32-1.49; P < .01) and lacerations/punctures (7.5%; relative risk, 3.31; 95% confidence interval, 2.93-3.74; P < .01) than were girls (12.7% and 2.3%, respectively). Girls were more likely to have ankle injuries (21.8%; relative risk, 1.38; 95% confidence interval, 1.33-1.45; P < .01) and knee injuries (12.9%; relative risk, 1.25; 95% confidence interval, 1.15-1.35; P < .01) than were boys (15.7% and 10.4%, respectively). Girls were more likely to have sprains or strains (42.4%) than were boys (31.3%; relative risk, 1.36; 95% confidence interval, 1.31-1.40; P < .01). Children 2 to 4 years old sustained a higher proportion of face and head/neck injuries (41.0%) than did older children (15.5%; relative risk, 2.65; 95% confidence interval, 2.09-3.36; P < .01).

CONCLUSION

When comparing these data to available national statistics that estimate participation in youth soccer, true injury rates may actually be decreasing for boys and girls. Young children should be closely supervised because of risk of head injuries and rate of hospitalization. The establishment of a national database of soccer participation and injury data is needed to better identify injury risks.

A systematic review on ankle injury and ankle sprain in sports

This article systematically reviews epidemiological studies on sports injury from 1977 to 2005 in which ankle injury was included. A total of 227 studies reporting injury pattern in 70 sports from 38 countries were included. A total of 201,600 patients were included, with 32,509 ankle injuries. Ankle injury information was available from 14,098 patients, with 11 847 ankle sprains. Results show that the ankle was the most common injured body site in 24 of 70 included sports, especially in aeroball, wall climbing, indoor volleyball, mountaineering, netball and field events in track and field. Ankle sprain was the major ankle injury in 33 of 43 sports, especially in Australian football, field hockey, handball, orienteering, scooter and squash. In sports injuries throughout the countries studied, the ankle was the second most common injured body site after the knee, and ankle sprain was the most common type of ankle injury. The incidence of ankle injury and ankle sprain was high in court games and team sports, such as rugby, soccer, volleyball, handball and basketball. This systematic review provides a summary of the epidemiology of ankle injury in sports.

Neuromuscular control training programs and noncontact anterior cruciate ligament injury rates in female athletes: a numbers-needed-to-treat analysis

OBJECTIVE

To determine the numbers needed to treat (NNT) and relative risk reduction (RRR) associated with neuromuscular training programs aimed at preventing noncontact anterior cruciate ligament (ACL) injuries in female athletes.

DATA SOURCES

We searched PubMed, MEDLINE, SPORT Discus, CINAHL, and Web of Science from 1966 through 2005 using the terms knee, injury, anterior cruciate ligament, ACL, prevention, plyometric, and neuromuscular training.

STUDY SELECTION

Selected articles were from peer-reviewed journals written in English that described original research studies comparing neuromuscular training programs with control programs to determine the number of noncontact ACL injuries per event exposure or hours of playing time. Five studies met the inclusion criteria and were independently rated by 3 reviewers using the Physiotherapy Evidence Database (PEDro) scale. Consensus PEDro scores ranged from 4 to 7 out of 10.

DATA EXTRACTION

We used numbers of subjects, ACL injuries, and injury exposure rates to calculate NNT and RRR for each study. The NNT calculations from all studies were based on the number of players across 1 competitive season and were described as NNT benefit or NNT harm.

DATA SYNTHESIS

All 5 studies demonstrated a prophylactic effect due to the neuromuscular training programs. The pooled NNT estimates showed that 89 individuals (95% confidence interval: 66 to 136) would need to participate in the prophylactic training program to prevent 1 ACL injury over the course of 1 competitive season. Pooled RRR was 70% (95% confidence interval: 54% to 80%) among individuals who participated in the intervention program. One high-quality randomized control trial and 4 medium-quality prospective cohort studies showed mostly consistent findings. Thus, a Strength of Recommendation Taxonomy level of evidence of 1 with a grade B recommendation supports the use of neuromuscular training programs in the prevention of noncontact ACL injuries in female athletes.

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.

Injuries in team sport tournaments during the 2004 Olympic Games

BACKGROUND

Several authors have analyzed the incidence of injuries in a given sport, but only a few have examined the exposure-related incidence of injuries in different types of sports using the same methodology.

PURPOSE

Analysis of the incidence, circumstances, and characteristics of injuries in different team sports during the 2004 Olympic Games.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

During the 2004 Olympic Games, injuries in 14 team sport tournaments (men's and women's soccer, men's and women's handball, men's and women's basketball, men's and women's field hockey, baseball, softball, men's and women's water polo, and men's and women's volleyball) were analyzed. After each match, the physician of the participating teams or the official medical representative of the sport completed a standardized injury report form. The mean response rate was 93%.

RESULTS

A total of 377 injuries were reported from 456 matches, an incidence of 0.8 injuries per match (95% confidence interval, 0.75-0.91) or 54 injuries per 1000 player matches (95% confidence interval, 49-60). Half of all injuries affected the lower extremity; 24% involved the head or neck. The most prevalent diagnoses were head contusion and ankle sprain. On average, 78% of injuries were caused by contact with another player. However, a significantly higher percentage of noncontact (57%) versus contact injuries (37%) was expected to prevent the player from participating in his or her sport. Significantly more injuries in male players (46%) versus female players (35%) were expected to result in absence from match or training. The incidence, diagnosis, and causes of injuries differed substantially between the team sports.

CONCLUSION

The risk of injury in different team sports can be compared using standardized methodology. Even if the incidence and characteristics of injuries are not identical in all sports, prevention of injury and promotion of fair play are relevant topics for almost all team sports.

The incidence of ankle sprains in soccer

This study investigated the relationship between exposure time and ankle sprains in soccer. Forty-one teams (639 players) from four male senior soccer divisions at different levels of skill (divisions I-VI) were followed prospectively for 1 year. The exposure to soccer and the number of injuries per player were higher in higher divisions, but the injury incidence, percentage of ankle injuries and incidence of ankle injuries were the same at different levels of skill. Of all injuries 17 to 20% were ankle sprains and the incidence varied between 1.7 to 2.0 ankle injuries per 1,000 hours of exposure. Since players with previous ankle problems run an increased risk of reinjury we suggest that these players receive preventive advice.