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Re-injuries in Professional Football: The UEFA Elite Club Injury Study
Abstract
Since the start in 2001, the UEFA Elite Club Injury Study (UEFA-ECIS) has collected player exposure and injury data from nearly 50 top-level football clubs from 17 different countries. In total, 13,000 injuries during 1.8 million hours have been registered between 2001 and 2016, making it the biggest database of its kind in professional football. A top-level football club will on average suffer just over 50 injuries per season, and 17% of them will be re-injuries. Reducing injury recurrence rates should clearly be a priority for professional clubs in order to decrease the total injury burden.
... Moreover, its high recurrence rate in the weeks following return to play (RTP) is a cause of concern in professional soccer [18][19][20]. Its recurrence rate is between 5% and 6.4% in the short-term (the first week following RTP) [21,22], between 50% and 77% in the medium-term (between the first and second month after RTP), and 15% in the long term (between 5-6 months after RTP) [22]. For these reasons, a successful management of these injuries constitutes a challenge for clinicians in order to define specific protocols of treatment that integrate biological stimulus [23][24][25] and reconditioning programs adapted for elite competition [17]. ...
... Moreover, its high recurrence rate in the weeks following return to play (RTP) is a cause of concern in professional soccer [18][19][20]. Its recurrence rate is between 5% and 6.4% in the short-term (the first week following RTP) [21,22], between 50% and 77% in the medium-term (between the first and second month after RTP), and 15% in the long term (between 5-6 months after RTP) [22]. For these reasons, a successful management of these injuries constitutes a challenge for clinicians in order to define specific protocols of treatment that integrate biological stimulus [23][24][25] and reconditioning programs adapted for elite competition [17]. ...
... An important part of the study was that the participants did not suffer any re-injury or serious adverse effects in 20 weeks following RTP. Epidemiological research has reported that the recurrence rate of a reinjury to the rectus femoris in the weeks following the RTP varied between 5% [21] and 6.4% [22]. As in previous studies, only post-needling soreness was reported, which is a frequent effect after PNE, usually lasting less than 48 h [60]. ...
Rectus femoris muscle strains are one of the most common injuries occurring in sports such as soccer. The purpose of this study was to describe the safety and feasibility of a combination of percutaneous needle electrolysis (PNE) and a specific rehab and reconditioning program (RRP) following an injury to the rectus femoris in professional soccer players. Thirteen professional soccer players received PNE treatment 48 h after a grade II rectus femoris muscle injury, followed by a the RRP 24 h later. Assessment of recovery from injury was done by registering the days taken to return to train (RTT), return to play (RTP), and structural and functional progress of the injured muscle was registered through ultrasound imaging and match-GPS parameters. Also, adverse events and reinjuries were recorded in the follow up period of twenty weeks. The RTT registered was 15.62 ± 1.80 days and RTP was 20.15 ± 2.79 days. After fourteen days, the ultrasound image showed optimal repair. Match-GPS parameters were similar before and after injury. There were no relapses nor were any serious adverse effects reported during the 20-week follow-up after the RTP. A combination of PNE and a specific RRP facilitated a faster RTP in previously injured professional soccer players enabling them to sustain performance and avoid reinjuries.
... Desta forma, e pelo impacto não somente na vida dos atletas, mas também na economia dos clubes e equipes esportivas, as ocorrências e tipos de lesões tem sido um dos campos mais estudados no meio esportivo (Cumps et al., 2008;Öztürk & Kılıç, 2013;van Mechelen, 1997), e os resultados das pesquisas desenvolvidas indicam que na prática profissional do futebol não apenas a incidência, mas também a reincidência de lesões têm ISSN: 2525-8761 ocorrido com maior frequência a cada temporada, e estas novas taxas de lesões impactam diretamente o desempenho dos jogadores na atual temporada (Hägglund et al., 2018), principalmente pelas altas taxas de reincidência de lesões, até 77%, no início das temporadas (Hägglund et al., 2018). Em contrapartida, também é sugerido que tratamentos reabilitativos pós temporada e pós lesões servem para evitar e prevenir novas lesões, e reaparecimento das antigas (Bueno et al., 2021;Hägglund et al., 2007). ...
... Desta forma, e pelo impacto não somente na vida dos atletas, mas também na economia dos clubes e equipes esportivas, as ocorrências e tipos de lesões tem sido um dos campos mais estudados no meio esportivo (Cumps et al., 2008;Öztürk & Kılıç, 2013;van Mechelen, 1997), e os resultados das pesquisas desenvolvidas indicam que na prática profissional do futebol não apenas a incidência, mas também a reincidência de lesões têm ISSN: 2525-8761 ocorrido com maior frequência a cada temporada, e estas novas taxas de lesões impactam diretamente o desempenho dos jogadores na atual temporada (Hägglund et al., 2018), principalmente pelas altas taxas de reincidência de lesões, até 77%, no início das temporadas (Hägglund et al., 2018). Em contrapartida, também é sugerido que tratamentos reabilitativos pós temporada e pós lesões servem para evitar e prevenir novas lesões, e reaparecimento das antigas (Bueno et al., 2021;Hägglund et al., 2007). ...
Objetivo: Verificar a associação da posição do atleta com o tipo de lesão dos membros inferiores em profissionais de futebol do Norte do Brasil. Métodos: 44 profissionais de futebol da cidade de Manaus foram descobertos um questionário com dados sobre a idade, a posição de jogo, o tipo e o local da lesão. Resultados: Encontrou-se associação estatisticamente significativa entre o tipo de lesão com a posição do jogador ( p= 0,035). Os dois tipos de lesão mais recorrentes nos atletas da cidade de Manaus foram lesões ligamentares (52,27%) e musculares (29,55%), sendo que o ligamento do tornozelo e a musculatura posterior da coxa foram os locais mais afetados, ambos com 15,91% de número. Conclusão: Foram encontradas associações positivas entre a posição e o tipo de lesão em futebol americano do Norte do Brasil.
... Hamstring muscle injuries typically occur along the proximal musculotendinous junction but may also occur anywhere in the muscle belly between the origin and insertion (Ropiak et al., 2012). The severity of the injury can be estimated according to the number of days the athlete remains absent from training sessions or matches and is classified into four levels: minimal, 0-3 days; mild, 4-7 days; moderate, 8-28 days; and severe, >28 days (Hägglund et al., 2018). ...
Purpose. The Nordic hamstring exercise (NHE) has been shown to be successful in reducing hamstring muscle injury (HMI), which is one of the most common non-contact injuries of the lower limbs. This is especially pertinent in sports that require acceleration, maximal sprints, and sudden changes in the direction of running and sprinting, such as soccer and rugby. This study aimed to evaluate the awareness, implementation, and opinions of athletes worldwide regarding the effectiveness of NHE in preventing hamstring injury.
Materials and methods. A self-administered questionnaire was distributed to 1500 athletes from different sports. The survey consisted of six questions covering country, gender, type of sport, awareness, implementation, and opinions of athletes worldwide regarding the effectiveness of NHE in preventing hamstring injury. The survey was available in ten different languages.
Results. A total of 1142 male and female athletes from different sports participated in the survey. More than half of the athletes 641 (56%) were aware of NHE, and only 519 (45.4 %) were implementing NHE in their current training routines. Athletes who implemented NHE reported a positive opinion regarding the program’s effectiveness with a score of 8.4 ± 1 out of 10.
Conclusions. Many athletes were aware of NHE and implemented it in their training routine since they found it to be effective in decreasing hamstring injury rates. However, additional work must be done to educate athletes about the importance of implementing this exercise and its effectiveness in preventing hamstring injury.
... In the former three decades, there is a growing body of evidence concerning the efficacy of preventive measures of sports injuries [1][2][3] and reinjuries (defined as an injury of the same type and at the same site as an index injury in the preceding year) [4,5]. This comes handy as the number of participants in organized youth sports is on the rise, with increasing number of games, and more competitive sporting modalities seem to be demanding more from human development domains (and these are not discrete, i.e., they constantly interact). ...
Prevention of sports-related injury is partial and significantly conceivable and yields important health, sportive, societal, and economic benefits. Every stakeholder within sports should embrace and boost prevention of sports-related injuries. It brings and enables superior outcomes in health, sports, and financial scopes. It is an exercise of professionalism, governance, and clever management. Knowledge and its translation into practice require hard work and transdisciplinary. However, broadening the involvement of professionals’ areas cannot preclude the need to ongoing research of core subjects of sports medicine such as epidemiology, anatomy, physiology, biomechanics, neurosciences, planning and prescription of preventive measures, and others. Yet, science of implementation and models from social sciences are crucial to successful implementation of preventable measures. There is a responsibility hierarchy that needs to be definitely and entirely called into action. No doubts could subsist that Prevention is the best remedy (Portuguese saying). Injury prevention measures have to merge as core value and culture signature of every sports organization and ruling bodies.
Introduction: Somatotype was developed by W.H. Sheldon (1940) based on the constitutional
psychology which attempted to associate human temperament with body type. The present study was aimed
to find out if any association presented between somatotype and depression.
Methods: 62 male and female
college students, age ranged from 18-21 yr, were studied. Somatotype was calculated using Heath-Carter
method (1990) and Beck Depression Inventory (1996) method was used for depression.
Results: Normal
depression level were observed in Mesomorphic endomorph category (35.7%), in Endomorphic ectomorph
category (25 %), in Ectomorphic endomorph category (50%), in Balance ectomorph category (85.7 %), in
Endomorphic mesomorph category (75 %) and in Balanced ectomorph category (50%). Mild depression was
observed in Mesomorphic endomorph category (28.6%), in Endomorphic ectomorph category (37.5%), in
Ectomorphic endomorph category (25%), in Balanced endomorph category (14.3%), in Endomorphic
mesomorph category (25%), and in Balanced ectomorph category (50%). Border line depression were
observed in Mesomorphic endomorph category (10.7%), in Endomorphic ectomorph category (25 %), in
Ectomorphic endomorph category (12.5 %). Moderate depression was observed in Mesomorphic endomorph
category (14.3 %), and in Endomorphic ectomorph category (12.5%). Severe and extreme depression levels
were observed only in Mesomorphic endomorph category (7.2 % and 3.6% respectively). Depression level of
75 % Mesomorphic endomorph category were non-clinical and rest were clinical. 87.5 % students with
Endomorphic ectomorph category were with non-clinical depression level, rest were with clinical depression
level. Depression level of 87.5 % Ectomorphic endomorph category were non-clinical, only 12.5 % were
clinical. The correlation coefficients (r) were 0.2 (between endomorphy and depression), 0.1 (between
mesomorphy and depression) and 0.1 (between ectomorphy and depression).
Conclusion: Thus, from the
above study, it could be concluded that somatotype categories did not have any significant association with
depression level. Further study is recommended. Somatotype is just a description of body shape and size,
rather than a reflection of mind.
Conflict of Interest : It doesn’t exist.
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32(12), 1208-1211.
The book is intended for everyone involved in football practice, but primarily for professional medical personnel and coaches whose task is the prevention and rehabilitation of unwanted conditions and injuries that result in the absence of players from football fields.
The problem of injuries in modern football is a complex and financially very important factor. Injury classification, its frequency and severity are usually evaluated against 1000 working hours (training and playing matches) of a professional team. The injury of a professional football player has multiple repercussions on the team itself, but also on the financial structure.
In terms of content, the book defines several important factors of the health condition of football players in professional football through the presentation of tools for prevention, mechanisms of the occurrence and structure of injuries, their classifications and management of the process of return to the field (RTP, English "Return to play").
How was this book put together?
Through structure, the book deals with injuries in professional football against frequency and complexity, and topologically according to regions of origin. The content of the text is based on the use of the most relevant information from scientific literature published by leading scientists and experts from the world of football. Each chapter opens with interesting facts, and a complete understanding of the information and assembling a complete picture occurs after reading the entire text. Therefore, dear reader, we recommend that you read the book in its entirety, in order to have a full understanding of the context.
The experience of all the authors in a scientific, but also professional sense, greatly helped to present the content in a very accessible and appropriate way. The content is supported by a large number of pictures and graphic displays that hold attention and raise the level of understanding of the content.
Background:
Rehabilitation progression and return-to-play (RTP) decision making following hamstring strain injury (HSI) can be challenging for clinicians, owing to the competing demands of reducing both convalescence and the risk of re-injury. Despite an increased focus on the RTP process following HSI, little attention has been paid to rehabilitation progression and RTP criteria, and subsequent time taken to RTP and re-injury rates.
Objective:
The aim of this systematic review is to identify rehabilitation progression and RTP criteria implemented following HSI and examine the subsequent time taken to RTP and rates of re-injury.
Methods:
A systematic literature review of databases MEDLINE, CINAHL, SPORTDiscus, Cochrane Library, Web of Science and EMBASE was conducted to identify studies of participants with acute HSI reporting time taken to RTP and rates of re-injury after a minimum 6-month follow-up. General guidelines and specific criteria for rehabilitation progression were identified for each study. In addition, RTP criteria were identified and categorised as performance tests, clinical assessments, isokinetic dynamometry or the Askling H-test.
Results:
Nine studies were included with a total of 601 acute HSI confirmed by clinical examination or magnetic resonance imaging within 10 days of initial injury. A feature across all nine studies was that the injured individual's perception of pain was used to guide rehabilitation progression, whilst clinical assessments and performance tests were the most frequently implemented RTP criteria. Mean RTP times were lowest in studies implementing isokinetic dynamometry as part of RTP decision making (12-25 days), whilst those implementing the Askling H-test had the lowest rates of re-injury (1.3-3.6%).
Conclusions:
This systematic review highlights the strong emphasis placed on the alleviation of pain to allow HSI rehabilitation progression, and the reliance on subjective clinical assessments and performance tests as RTP criteria. These results suggest a need for more objective and clinically practical criteria, allowing a more evidence-based approach to rehabilitation progression, and potentially reducing the ambiguity involved in the RTP decision-making process.
The return to sport from injury is a difficult multifactorial decision, and risk of reinjury is an important component. Most protocols for ascertaining the return to play status involve assessment of the healing status of the original injury and functional tests which have little proven predictive ability. Little attention has been paid to ascertaining whether an athlete has completed sufficient training to be prepared for competition. Recently, we have completed a series of studies in cricket, rugby league and Australian rules football that have shown that when an athlete's training and playing load for a given week (acute load) spikes above what they have been doing on average over the past 4 weeks (chronic load), they are more likely to be injured. This spike in the acute:chronic workload ratio may be from an unusual week or an ebbing of the athlete's training load over a period of time as in recuperation from injury. Our findings demonstrate a strong predictive (R(2)=0.53) polynomial relationship between acute:chronic workload ratio and injury likelihood. In the elite team setting, it is possible to quantify the loads we are expecting athletes to endure when returning to sport, so assessment of the acute:chronic workload ratio should be included in the return to play decision-making process.
Synopsis Achilles tendinopathy is a common overuse injury in athletes involved in running and jumping activities and sports. The intervention with the highest level of evidence is exercise-therapy and it is recommended that all patients initially be treated with exercise for at least 3 months prior to considering other treatment options. Recovery from Achilles tendinopathy can take up to a year and there is a high propensity for recurrence especially during the return to sport phase. The extent of the tendon injury, the age and sex of the athlete, the magnitude of pain/symptoms, the extent of impairments, and the demands of the sport all need to be considered when planning for return to sport. This clinical commentary describes an approach to return to sport for patients with midportion Achilles tendinopathy. The aim of the return to sport program is to facilitate the decision-making process in returning an athlete with midportion Achilles tendinopathy back to full sport participation and minimize the chances for recurrence of the injury. J Orthop Sports Phys Ther, Epub 21 Sep 2015. doi:10.2519/jospt.2015.5885.
Abstract
Background Our 2012 review on therapeutic interventions for acute hamstring injuries found a lack of high-quality studies. The publication of new studies warranted an update.
Objectives To update and reanalyse the efficacy of conservative treatments for hamstring injury.
Data sources PubMed, EMBASE, Web of Science, Cochrane library, CINAHL and SPORTDiscus were searched till mid-February 2015.
Study eligibility criteria Randomised controlled trials (RCTs) on the effect of conservative interventions versus a control group or other intervention for hamstring injuries (HI) were included.
Data analysis The search results were screened independently by two authors. Risk of bias assessment was performed using a modified Downs and Black scale with a maximum score of 28. Meta-analysis was performed, where possible.
Main results 10 RCTs (526 participants), including 6 new RCTs, were identified. Two RCTs were of good/excellent quality, the rest were fair or poor (median Downs and Black score 16 (IQR 9)). Meta-analysis of two studies on rehabilitation (lengthening) exercises showed a significantly reduced time to return to play (HR 3.22 (95% CI 2.17 to 4.77), p<0.0001) but no difference in risk of re-injury. Meta-analysis of three studies investigating platelet-rich plasma (PRP) showed no effect when compared to control (HR 1.03 (95% CI 0.87 to 1.22), p=0.73). Limited evidence was found that progressive agility and trunk stability training may reduce re-injury rates.
Conclusions Meta-analysis showed superior efficacy for rehabilitation exercises. PRP injection had no effect on acute hamstring injury. Limited evidence was found that agility and trunk stabilisation may reduce re-injury rates. The limitations identified in the majority of RCTs should improve the design of new hamstring RCTs.
Context:
Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries.
Objective:
To investigate the incidence and characteristics of injuries in the Dutch premier soccer league.
Design:
Cohort study.
Setting:
The Dutch premier soccer league.
Patients or other participants:
During the 2009-2010 soccer season, a total of 217 professional soccer players from 8 teams were prospectively followed.
Main outcome measure(s):
The medical staff recorded time-loss injuries, including information on injuries (ie, type, body part, duration) and exposure data for training sessions and matches.
Results:
A total of 286 injuries were recorded, affecting 62.7% of the players. The overall injury incidence was 6.2 injuries per 1000 player-hours, 2.8 in training sessions and 32.8 in matches. Most of the recorded injuries were acute (68.5%). Eight percent of the injuries were classified as recurrent. Injuries were most likely to be located in the lower extremities (82.9%). Injury time loss ranged from 1 to 752 days, with a median of 8 days. Knee injuries had the greatest consequences in terms of days of absence from soccer play (on average, 45 days). The most common diagnosis was muscle/tendon injury of the lower extremities (32.9%).
Conclusions:
Injury risk in the Dutch premier soccer league is high, especially during matches. Preventive measures should focus on the most common diagnoses, namely, muscle/tendon injuries of the lower extremities.
Objective: to compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season.
Design: a prospective two-cohort design.
Methods: during the 2009-2010 season, 456 Dutch male amateur soccer players and 217 professional players were prospectively followed. Information on injuries and individual exposure to all soccer activities were recorded in both cohorts. Injuries were recorded using the time-loss definition.
Results: In total, 424 injuries were recorded among 274 of the amateur players (60.1% injured players) and 286 injuries were sustained by 136 (62.7% injured players) of the professional players (p=0.52). Compared to the professionals, the injury incidence during training sessions was higher among amateurs (p=0.01), but the injury incidence among professionals was higher during matches (p<0.001). Professional players also had a higher incidence of minimal injuries (p<0.001), whereas the incidence of moderate and severe injuries was higher for amateurs (all p<0.001). Lastly, professional players sustained more overuse injuries (p=0.02), whereas amateurs reported more recurrent injuries (p<0.001).
Conclusions: The abovementioned differences in injury rates between amateur and professional players in the Netherlands might be explained by the difference in the level at which they play, since factors like the availability of medical support and/or the team size may influence the injury risk and characteristics.
The influence of fixture congestion on injury rates and team performance has only been scarcely investigated.
To study associations between recovery time and match load and injury rates and team performance in professional football.
Exposure and time loss injuries were registered prospectively from 27 teams over 11 seasons. Matches were grouped according to recovery days before each match (≤3 vs >3 days, and ≤4 vs ≥6 days). Injury rates and team performance were compared between groups. Match load in match sequences containing five consecutive matches was determined by the number of days separating the first match and the last training session during that match sequence. Linear regression was used to study associations between match load and injury rates and team performance.
Team performance showed no association with match load, or recovery days prior to matches, except for Europa League matches that indicated more matches lost with short recovery (≤3 days) (p=0.048). Total injury rates and muscle injury rates were increased in league matches with ≤4 days compared with ≥6 days' recovery (RR 1.09, 95% CI 1.00 to 1.18, and RR 1.32, 95% CI 1.15 to 1.51, respectively), specifically hamstring and quadriceps injuries. High match load was associated with increase in muscle injury rate in matches in the same match sequence (p=0.012), and increase in ligament injury rate in training in the subsequent match sequence (p=0.003).
Fixture congestion was associated with increased muscle injury rates but had no, or very limited, influence on team performance.
Limited information is available on the variation in injury rates over multiple seasons of professional football.
To analyse time-trends in injury characteristics of male professional football players over 11 consecutive seasons.
A total of 1743 players comprising 27 teams from 10 countries were followed prospectively between 2001 and 2012. Team medical staff recorded individual player exposure and time loss injuries.
A total of 8029 time loss injuries were recorded. The match unavailability due to injury was 14% and constant over the study period. On average, a player sustained two injuries per season, resulting in approximately 50 injuries per team and season. The ligament injury rate decreased during the study period (R(2)=0.608, b=-0.040, 95% CI -0.065 to -0.016, p=0.005), whereas the rate of muscle injury (R(2)=0.228, b=-0.013, 95% CI -0.032 to 0.005, p=0.138) and severe injury (R(2)=0.141, b=0.015, 95% CI -0.013 to 0.043, p=0.255) did not change over the study period. In addition, no changes in injury rates over the 11-year period were found for either training (R(2)=0.000, b=0.000, 95% CI -0.035 to 0.034, p=0.988) or match play (R(2)=0.282, b=-0.015, 95% CI -0.032 to 0.003, p=0.093).
The injury rate has decreased for ligament injuries over the last 11 years, but overall training, match injury rates and the rates of muscle injury and severe injury remain high.
Ankle injury is common in football, but the circumstances surrounding them are not well characterised.
To investigate the rates, especially time-trends, and circumstances of ankle injuries in male professional football.
27 European clubs with 1743 players were followed prospectively between 2001/2002 and 2011/2012. Time loss injuries and individual-player exposure during training sessions and matches were recorded. Injury rate was defined as the number of injuries/1000 h.
A total of 1080 ankle injuries were recorded (13% of all injuries) with lateral ligament ankle sprain being the most common injury subtype (51% of all ankle injuries). The rates of ankle injury and ankle sprain were 1/1000 h and 0.7/1000 h, respectively. The ankle sprain rate declined slightly over time during the 11-year study period (on average 3.1%/season) with a statistically significant seasonal trend (p=0.041). Foul play according to the referee was involved in 40% of the match-related ankle sprains. Syndesmotic sprains and ankle impingement were uncommon causes of time loss (3% each of all ankle injuries).
Lateral ligament ankle sprain constituted half of all ankle injuries in male professional football, whereas ankle impingement syndromes were uncommon. The ankle sprain rate decreased slightly over time, but many ankle sprains were associated with foul play. Our data extend the body of literature that provides football policy makers with a foundation to review existing rules and their enforcement.
Background There is limited information about Achilles tendon disorders in professional football.
Aims To investigate the incidence, injury circumstances, lay-off times and reinjury rates of Achilles tendon disorders in male professional football.
Methods A total of 27 clubs from 10 countries and 1743 players have been followed prospectively during 11 seasons between 2001 and 2012. The team medical staff recorded individual player exposure and time-loss injuries.
Results A total of 203 (2.5% of all injuries) Achilles tendon disorders were registered. A majority (96%) of the disorders were tendinopathies, and nine were partial or total ruptures. A higher injury rate was found during the preseason compared with the competitive season, 0.25 vs 0.18/1000 h (rate ratio (RR) 1.4, 95% CI 1.1 to 2.0; p=0.027). The mean lay-off time for Achilles tendinopathies was 23±37 (median=10, Q1=4 and Q3=24) days, while a rupture of the Achilles tendon, on average, caused 161±65 (median=169, Q1=110 and Q3=189) days of absence. Players with Achilles tendon disorders were significantly older than the rest of the cohort, with a mean age of 27.2±4 years vs 25.6±4.6 years (p<0.001). 27% of all Achilles tendinopathies were reinjuries. A higher reinjury risk was found after short recovery periods (31%) compared with longer recovery periods (13%) (RR 2.4, 95% CI 2.1 to 2.8; p<0.001).
Conclusions Achilles tendon disorders account for 3.8% of the total lay-off time and are more common in older players. Recurrence is common after Achilles tendinopathies and the reinjury risk is higher after short recovery periods.
Background Previously, no difference in acute injury rate has been found when playing football on artificial turf (AT) compared with natural grass (NG).
Aim To compare acute injury rates in professional football played on AT and NG at the individual player level; and to compare, at club level, acute and overuse injury rates between clubs that have AT at their home venue (AT clubs) and clubs that have NG (NG clubs).
Methods 32 clubs (AT, n=11; NG, n=21) in the male Swedish and Norwegian premier leagues were followed prospectively during the 2010 and 2011 seasons. Injury rate was expressed as the number of time loss injuries/1000 h and compared with rate ratio (RR) and 99% CI.
Results No statistically significant differences were found in acute injury rates on AT compared with NG during match play (RR 0.98, 99% CI 0.79 to 1.22) or training (RR 1.14, 99% CI 0.86 to 1.50) when analysing at the individual player level. When analysing at the club level, however, AT clubs had a significantly higher acute training injury rate (RR 1.31, 99% CI 1.04 to 1.63) and overuse injury rate (RR 1.38, 99% CI 1.14 to 1.65) compared with NG clubs.
Conclusions At the individual player level, no significant differences were found in acute injury rates when playing on AT compared with NG. However, clubs with AT at their home venue had higher rates of acute training injuries and overuse injuries compared with clubs that played home matches on NG.
Background:
The influence of injuries on team performance in football has only been scarcely investigated.
Aim:
To study the association between injury rates and team performance in the domestic league play, and in European cups, in male professional football.
Methods:
24 football teams from nine European countries were followed prospectively for 11 seasons (2001-2012), including 155 team-seasons. Individual training and match exposure and time-loss injuries were registered. To analyse the effect of injury rates on performance, a Generalised Estimating Equation was used to fit a linear regression on team-level data. Each team's season injury rate and performance were evaluated using its own preceding season data for comparison in the analyses.
Results:
7792 injuries were reported during 1 026 104 exposure hours. The total injury incidence was 7.7 injuries/1000 h, injury burden 130 injury days lost/1000 h and player match availability 86%. Lower injury burden (p=0.011) and higher match availability (p=0.031) were associated with higher final league ranking. Similarly, lower injury incidence (p=0.035), lower injury burden (p<0.001) and higher match availability (p<0.001) were associated with increased points per league match. Finally, lower injury burden (p=0.043) and higher match availability (p=0.048) were associated with an increase in the Union of European Football Association (UEFA) Season Club Coefficient, reflecting success in the UEFA Champions League or Europa League.
Conclusions:
Injuries had a significant influence on performance in the league play and in European cups in male professional football. The findings stress the importance of injury prevention to increase a team's chances of success.
Background:
Player activities in soccer matches are influenced by the match result and match venue. It is not known whether injury rates are influenced by these factors.
Purpose:
To investigate whether there are associations between injury rates and the match result, venue, and type of competition in male soccer.
Study design:
Cohort study; Level of evidence, 3.
Methods:
Twenty-six professional clubs from 10 countries were followed prospectively during 9 seasons (2001-2002 to 2009-2010). All matches, and injuries occurring in these matches, were registered by the team's medical staff. An injury was registered if it resulted in player absence from training or matches. Information about match result, venue, and type of competition for all reported matches was gathered by the authors from online databases. Injury rates in matches with varying match characteristics were compared by use of generalized estimating equations. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.
Results:
A total of 2738 injuries during 6010 matches were registered. There were no associations between odds of 1 injury occurrence and match result or type of competition, whereas the odds were decreased in matches played away compared with home matches (OR, 0.89; 95% CI, 0.80-0.99). The odds of 2 or more injury occurrences in a match were increased in matches resulting in a draw (OR, 1.39; 95% CI, 1.15-1.69) or loss (OR, 1.66; 95% CI, 1.38-1.98) compared with matches won and were decreased in other cup matches compared with league matches (OR, 0.57; 95% CI, 0.39-0.84) and in matches played away compared with home matches (OR, 0.70; 95% CI, 0.60-0.82). Finally, injuries with more than 1 week's absence occurred more frequently in Champions League matches compared with league matches both for matches with 1 injury (OR, 1.26; 95% CI, 1.09-1.45) and matches with 2 or more injuries (OR, 1.57; 95% CI, 1.13-2.20).
Conclusion:
The odds of 2 or more injury occurrences in professional soccer were higher in matches resulting in a loss or a draw compared with a win, whereas the odds of injury occurrences were lower in matches played away compared with home matches. The rate of moderate and severe injuries increased with the importance of the match.
Background Medial collateral ligament (MCL) injury is the most common knee ligament injury in professional football.
Aim To investigate the rate and circumstances of MCL injuries and development over the past decade.
Methods Prospective cohort study, in which 27 professional European teams were followed over 11 seasons (2001/2002 to 2011/2012). Team medical staffs recorded player exposure and time loss injuries. MCL injuries were classified into four severity categories. Injury rate was defined as the number of injuries per 1000 player-hours.
Results 346 MCL injuries occurred during 1 057 201 h (rate 0.33/1000 h). The match injury rate was nine times higher than the training injury rate (1.31 vs 0.14/1000 h, rate ratio 9.3, 95% CI 7.5 to 11.6, p<0.001). There was a significant average annual decrease of approximately 7% (p=0.023). The average lay-off was 23 days, and there was no difference in median lay-off between index injuries and reinjuries (18 vs 13, p=0.20). Almost 70% of all MCL injuries were contact-related, and there was no difference in median lay-off between contact and non-contact injuries (16 vs 16, p=0.74).
Conclusions This largest series of MCL injuries in professional football suggests that the time loss from football for MCL injury is 23 days. Also, the MCL injury rate decreased significantly during the 11-year study period.
Background:
Hamstring strains are common among soccer athletes, and they have a high incidence of recurrence. Among American collegiate soccer players, men have an overall higher incidence rate of hamstring strains than women.
Purpose:
This research compares the hamstring strain injury rates in event and athlete characteristics between male and female college soccer athletes.
Study design:
Descriptive epidemiology study.
Methods:
Data describing partial and complete hamstring strains were obtained from the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) for men's and women's soccer from 2004 to 2009. Incidence rate ratios (IRRs) comparing the incidence of hamstring strains between the sexes as well as during games versus practices and the preseason versus the in-season were calculated. χ(2) tests were used to compare the occurrence of hamstring strains across different event and athlete characteristics.
Results:
Men were 64% more likely than women to sustain a hamstring strain (IRR, 1.64; 95% CI, 1.37-1.96). Men had significantly higher rates of hamstring strains than women during both games (IRR, 2.42; 95% CI, 1.82-3.23) and practices (IRR, 1.34; 95% CI, 1.06-1.68). There were no differences between men and women in injury rates during the preseason, but men were significantly more likely to sustain a hamstring strain during the in-season (IRR, 1.98; 95% CI, 1.56-2.52). Men had a significantly higher proportion of recurrent hamstring strains compared with women (men, 22%; women, 12%; P = .003). There were no significant differences in the distribution of strains in event or athlete characteristics between men and women for first-time or recurrent hamstring strains.
Conclusion:
In collegiate soccer, men have significantly higher rates of hamstring strains than women, and regardless of the recurrence status, the event and athlete characteristics were similar for both sexes. Identifying common characteristics may assist in the targeted development of preventive and rehabilitative programs as well as continued research on hamstring strains among collegiate soccer players.
Background:
Muscle injury is the most common injury type in professional soccer players. Despite this, risk factors for common lower extremity injuries remain elusive.
Purpose:
To evaluate the effects of various player- and match-related risk factors on the occurrence of lower extremity muscle injury in male professional soccer.
Study design:
Cohort study; level of evidence, 2.
Methods:
Between 2001 and 2010, 26 soccer clubs (1401 players) from 10 European countries participated in the study. Individual player exposure and time loss muscle injuries in the lower extremity were registered prospectively by the club medical staffs during 9 consecutive seasons. Hazard ratios (HRs) were calculated for player-related factors from simple and multiple Cox regression, and odds ratios (ORs) were calculated for match-related variables from simple and multiple logistic regression, presented with 95% confidence intervals (CIs).
Results:
There were 2123 muscle injuries documented in the major lower extremity muscle groups: adductors (n = 523), hamstrings (n = 900), quadriceps (n = 394), and calf (n = 306). Injuries to the adductors (56%; P = .015) and quadriceps (63%; P< .001) were more frequent in the kicking leg. Multiple analysis indicated that having a previous identical injury in the preceding season increased injury rates significantly for adductor (HR, 1.40; 95% CI, 1.00-1.96), hamstring (HR, 1.40; 95% CI, 1.12-1.75), quadriceps (HR, 3.10; 95% CI, 2.21-4.36), and calf injuries (HR, 2.33; 95% CI, 1.52-3.57). Older players (above mean age) had an almost 2-fold increased rate of calf injury (HR, 1.93; 95% CI, 1.38-2.71), but no association was found in other muscle groups. Goalkeepers had reduced injury rates in all 4 muscle groups. Match play on away ground was associated with reduced rates of adductor (OR, 0.56; 95% CI, 0.43-0.73) and hamstring injuries (OR, 0.76; 95% CI, 0.63-0.92). Quadriceps injuries were more frequent during preseason, whereas adductor, hamstring, and calf injury rates increased during the competitive season.
Conclusion:
Intrinsic factors found to increase muscle injury rates in professional soccer were previous injury, older age, and kicking leg. Injury rates varied during different parts of the season and also depending on match location.
Background:
Current methods for injury registration in sports injury epidemiology studies may substantially underestimate the true burden of overuse injuries due to a reliance on time-loss injury definitions.
Objective:
To develop and validate a new method for the registration of overuse injuries in sports.
Methods:
A new method, including a new overuse injury questionnaire, was developed and validated in a 13-week prospective study of injuries among 313 athletes from five different sports, cross-country skiing, floorball, handball, road cycling and volleyball. All athletes completed a questionnaire by email each week to register problems in the knee, lower back and shoulder. Standard injury registration methods were also used to record all time-loss injuries that occurred during the study period.
Results:
The new method recorded 419 overuse problems in the knee, lower back and shoulder during the 3-month-study period. Of these, 142 were classified as substantial overuse problems, defined as those leading to moderate or severe reductions in sports performance or participation, or time loss. Each week, an average of 39% of athletes reported having overuse problems and 13% reported having substantial problems. In contrast, standard methods of injury registration registered only 40 overuse injuries located in the same anatomical areas, the majority of which were of minimal or mild severity.
Conclusion:
Standard injury surveillance methods only capture a small percentage of the overuse problems affecting the athletes, largely because few problems led to time loss from training or competition. The new method captured a more complete and nuanced picture of the burden of overuse injuries in this cohort.
Purpose
To investigate the epidemiology of upper extremity injuries in male elite football players and to describe their characteristics, incidence and lay-off times.
Methods
Between 2001 and 2011, 57 male European elite football teams (2,914 players and 6,215 player seasons) were followed prospectively. Time-loss injuries and exposure to training and matches were recorded on individual basis.
Results
In total, 11,750 injuries were recorded, 355 (3 %) of those affected the upper extremities giving an incidence of 0.23 injuries/1,000 h of football. The incidence in match play was almost 7 times higher than in training (0.83 vs. 0.12 injuries/1,000 h, rate ratio 6.7, 95 % confidence interval 5.5–8.3). As much as 32 % of traumatic match injuries occurred as a result of foul play situations. Goalkeepers had a significantly higher incidence of upper extremity injuries compared to outfield players (0.80 vs. 0.16 injuries/1,000 h, rate ratio 5.0, 95 % confidence interval 4.0–6.2). The average absence due to an upper extremity injury was 23 ± 34 days.
Conclusions
Upper extremity injuries are uncommon among male elite football players. Goalkeepers, however, are prone to upper extremity injury, with a five times higher incidence compared to outfield players.
Level of evidence
II.
Hamstring strain injuries (HSIs) are common in a number of sports and incidence rates have not declined in recent times. Additionally, the high rate of recurrent injuries suggests that our current understanding of HSI and re-injury risk is incomplete. Whilst the multifactoral nature of HSIs is agreed upon by many, often individual risk factors and/or causes of injury are examined in isolation. This review aims to bring together the causes, risk factors and interventions associated with HSIs to better understand why HSIs are so prevalent. Running is often identified as the primary activity type for HSIs and given the high eccentric forces and moderate muscle strain placed on the hamstrings during running these factors are considered to be part of the aetiology of HSIs. However, the exact causes of HSIs remain unknown and whilst eccentric contraction and muscle strain purportedly play a role, accumulated muscle damage and/or a single injurious event may also contribute. Potentially, all of these factors interact to varying degrees depending on the injurious activity type (i.e. running, kicking). Furthermore, anatomical factors, such as the biarticular organization, the dual innervations of biceps femoris (BF), fibre type distribution, muscle architecture and the degree of anterior pelvic tilt, have all been implicated. Each of these variables impact upon HSI risk via a number of different mechanisms that include increasing hamstring muscle strain and altering the susceptibility of the hamstrings to muscle damage. Reported risk factors for HSIs include age, previous injury, ethnicity, strength imbalances, flexibility and fatigue. Of these, little is known, definitively, about why previous injury increases the risk of future HSIs. Nevertheless, interventions put in place to reduce the incidence of HSIs by addressing modifiable risk factors have focused primarily on increasing eccentric strength, correcting strength imbalances and improving flexibility. The response to these intervention programmes has been mixed with varied levels of success reported. A conceptual framework is presented suggesting that neuromuscular inhibition following HSIs may impede the rehabilitation process and subsequently lead to maladaptation of hamstring muscle structure and function, including preferentially eccentric weakness, atrophy of the previously injured muscles and alterations in the angle of peak knee flexor torque. This remains an area for future research and practitioners need to remain aware of the multifactoral nature of HSIs if injury rates are to decline.
Hamstring injury is the single most common injury in professional football. MRI is commonly used to confirm the diagnosis and provide a prognosis of lay-off time.
To evaluate the use of MRI as a prognostic tool for lay-off after hamstring injuries in professional football players and to study the association between MRI findings and injury circumstances.
Prospective cohort study where 23 European professional teams, were followed between 2007 and 2011. Team medical staffs recorded individual player exposure and time-loss injuries. Radiological grading was performed using a modified Peetrons classification into four grades where grades 2 and 3 represent fibre disruption.
In total, 516 hamstring injuries occurred and 58% of these were examined by MRI. Thirteen per cent were grade 0 injuries, 57% grade 1, 27% of grade 2 and 3% of grade 3. Grade 0 and 1 injuries accounted for 56% (2141/3830 days) of the total lay-off. The lay-off time differed between all four radiological grades of injury (8±3, 17±10, 22±11 and 73±60 days, p<0.0001). Eighty-three per cent of injuries affected the biceps femoris while 11% and 5% occurred to the semimembranosus and semitendinosus, respectively. Re-injuries (N=34/207) constituted 16% of injuries. All re-injuries occurred to the biceps femoris.
MRI can be helpful in verifying the diagnosis of a hamstring injury and to prognosticate lay-off time. Radiological grading is associated with lay-off times after injury. Seventy per cent of hamstring injuries seen in professional football are of radiological grade 0 or 1, meaning no signs of fibre disruption on MRI, but still cause the majority of absence days.
Patellar tendinopathy is common among athletes in jumping sports and in sports with prolonged repetitive stress of the knee extensor apparatus. The epidemiology in soccer is not well described.
This study was undertaken to investigate and describe the epidemiology of patellar tendinopathy in elite male soccer players and evaluate potential risk factors.
Cohort study; Level of evidence, 2.
Between 2001 and 2009, the authors followed 51 European elite soccer clubs (2229 players) from 3 different cohorts: the Swedish First League cohort (SWE) and Union of European Football Associations (UEFA) Champions League cohort (UCL), both playing on natural grass; and the Artifical Turf cohort (ART), playing on third-generation artificial turf. Individual player exposure in training and matches and time-loss injuries were recorded.
In total, 137 patellar tendinopathies were recorded, comprising 1.5% of all injuries and corresponding to an incidence of 0.12 injuries/1000 hours. Each season, 2.4% of players were affected, with most injuries (61%) resulting in absence up to 1 week or less. Twenty percent of tendinopathies were recurrent complaints. No significant difference in season prevalence (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.60-1.44; P = .74) or incidence (rate ratio [RR] 1.20; 95% CI, 0.82-1.75; P = .36) was observed between teams playing on artificial turf and natural grass, respectively. Multivariate logistic regression showed that a high total exposure hours (OR, 1.02 per 10-hour increase; 95% CI, 1.00-1.04; P = .033) was a significant risk factor for patellar tendinopathy, and increased body mass was borderline significant (OR, 1.15 per 5-kg increase; 95% CI, 1.00-1.33; P = .055). In addition, 2 acute partial tendon ruptures were recorded, but no total rupture.
Although mainly mild in nature, patellar tendinopathy is a fairly common condition in elite soccer and the recurrence rate is high. Exposure to artificial turf did not increase the prevalence or incidence of injury. High total amount of exposure was identified as a risk factor for patellar tendinopathy.
Muscle injuries constitute a large percentage of all injuries in football.
To investigate the incidence and nature of muscle injuries in male professional footballers.
Cohort study; Level of evidence, 2.
Fifty-one football teams, comprising 2299 players, were followed prospectively during the years 2001 to 2009. Team medical staff recorded individual player exposure and time-loss injuries. The first-team squads of 24 clubs selected by the Union of European Football Associations as belonging to the best European teams, 15 teams of the Swedish First League, and another 15 European teams playing their home matches on artificial turf pitches were included. A muscle injury was defined as "a traumatic distraction or overuse injury to the muscle leading to a player being unable to fully participate in training or match play."
In total, 2908 muscle injuries were registered. On average, a player sustained 0.6 muscle injuries per season. A squad of 25 players can thus expect about 15 muscle injuries per season. Muscle injuries constituted 31% of all injuries and caused 27% of the total injury absence. Ninety-two percent of all muscle injuries affected the 4 major muscle groups of the lower limbs: hamstrings (37%), adductors (23%), quadriceps (19%), and calf muscles (13%). Sixteen percent of the muscle injuries were reinjuries. These reinjuries caused significantly longer absences than did index injuries. The incidence of muscle injury increased with age. When separated into different muscle groups, however, an increased incidence with age was found only for calf muscle injuries and not for hamstring, quadriceps, or hip/groin strains.
Muscle injuries are a substantial problem for players and their clubs. They constitute almost one third of all time-loss injuries in men's professional football, and 92% of all injuries affect the 4 big muscle groups in the lower limbs.
To identify target groups for injury prevention in male amateur soccer players under 35 years of age. A computer-assisted telephone survey with a 12-month recall period for injuries in a representative sample of Dutch citizens from the Injuries and Physical Activity Netherlands (IPAN)-database. A comparison of the volume of soccer injuries, the incidence and the need for medical attention per level of exposure and age category. The incidence in seniors was twice that of juniors (17.5% versus 8.1%; odds ratio (OR=2.4). In juniors the overall incidence was lowest in the category with the least amount of soccer exposure time (0-3 h: 2.9%; 3-5 h: 13.0%; 5+ h: 12.3%). A comparable result was found in seniors: (0-3 h: 12.0%; 3-5 h: 21.6%; 5+ h: 21.5%). Within each level of soccer exposure, a different incidence was found in juniors and seniors (0-3 h: OR=4.6; 3-5 h: OR=1.8; 5+ h: OR=1.9). Ankle, knee and upper leg injuries were most common (59.9%). Contusions, strains and sprains dominated (78.1%). Body region and type of injuries were similar in both age categories. Medical treatment for injuries was equally necessary in both age groups. Senior male amateur soccer players and particularly the more skilled seniors (involved in soccer at least 3 h per week), should be primarily targeted for studies on injury risk factors and prevention programs.
This study was conducted to determine if risk factors for groin injuries among male soccer players could be identified.
Previous groin injuries, reduced function scores, age, findings on clinical examination, and low isometric groin strength are associated with increased risk of new groin injuries.
Cohort study; Level of evidence, 3.
A total of 508 players representing 31 amateur teams were tested during the 2004 preseason for potential risk factors for groin injury through a questionnaire on previous injury and function score (Groin Outcome Score [GrOS]) and a clinical examination of the groin. Generalized estimating equations were used in univariate analyses to identify candidate risk factors, and factors with a P value <.10 were then examined in a multivariate model.
During the soccer season, 61 groin injuries affecting 55 legs (51 players) were registered. The total incidence of groin injuries was 0.6 injuries per 1000 playing hours (95% confidence interval [CI], 0.4-0.7), 0.3 injuries per 1000 training hours (95% CI, 0.2-0.4), and 1.8 injuries per 1000 match hours (95% CI, 1.2-2.5). In a multivariate analysis, previous acute groin injury (adjusted odds ratio [OR], 2.60; 95% CI, 1.10-6.11) and weak adductor muscles as determined clinically (adjusted OR, 4.28; 95% CI, 1.31-14.0) were significantly associated with increased risk of groin injuries. A multivariate analysis based only on acute time-loss injuries revealed the 40-m sprint test result (adjusted OR, 2.03 for 1 standard deviation change [injured group faster]; 95% CI, 1.06-3.88; P = .03) and functional testing of the rectal abdominal muscles (adjusted OR, 15.5 [painful in 19% of the players in the injured group compared to 16% in the uninjured group]; 95% CI, 1.11-217; P = .04) as significant risk factors.
A history of acute groin injury and weak adductor muscles are significant risk factors for new groin injuries.
Strain injuries of the posterior thigh are common in soccer. It seems that previous injury and age are important risk factors, but the literature is limited. This study was conducted to see if we could identify intrinsic risk factors for hamstring injuries among male soccer players.
We hypothesized that previous hamstring injuries, reduced function scores, abnormalities on a clinical examination, high maximum sprint speed, poor hamstring strength, or low hamstring/quadriceps ratio can predict increased risk of new hamstring injuries.
Cohort study; Level of evidence, 2.
A total of 508 players representing 31 amateur teams were tested during the 2004 preseason for potential risk factors for hamstring injury through a questionnaire on previous injury and function score (Hamstring Outcome Score [HaOS]), a clinical examination of the hamstring, and specific hamstring relevant tests. Generalized estimating equations were used in univariate analyses to identify candidate risk factors, and factors with a P value of <.10 were then examined in a multivariate model.
During the soccer season, 76 hamstring injuries, affecting 65 legs (61 players), were registered. Univariate analyses revealed previous acute hamstring injury (yes/no) (odds ratio [OR], 2.62; 95% confidence interval [CI], 1.54-4.45), HaOS function score with all subscores except "Soreness" (OR for a 10-point difference in total score, 1.29; 95% CI, 1.08-1.54), age (OR, 1.25; 95% CI, 0.96-1.63), and player position (P = .09) as candidate predictors of high injury risk. In a multivariate analysis, the most important risk factor for injuries to the hamstring was previous acute hamstring injury (yes/no) (adjusted OR, 2.19; 95% CI, 1.19-4.03; P = .01).
In a multivariate analysis, previous acute hamstring injury was found to be a significant risk factor for new hamstring injuries. Previously injured players have more than twice as high a risk of sustaining a new hamstring injury.
Groin injury is a common injury in football and a complicated area when it comes to diagnosis and therapy. There is a lack of comprehensive epidemiological data on groin injuries in professional football.
To investigate the incidence, pattern and severity of hip and groin injuries in professional footballers over seven consecutive seasons.
Prospective cohort study.
European professional football.
During the 2001/2 to 2007/8 seasons, between nine and 17 clubs per season (23 clubs in total) were investigated, accounting for 88 club seasons in total. Time loss injuries and individual exposure during club and national team training sessions and matches were recorded.
Injury incidence.
A total of 628 hip/groin injuries were recorded, accounting for 12-16% of all injuries per season. The total injury incidence was 1.1/1000 h (3.5/1000 match hours vs 0.6/1000 training hours, p<0.001) and was consistent over the seasons studied. Eighteen different diagnostic entities were registered, adductor (n = 399) and iliopsoas (n = 52) related injuries being the most common. More than half of the injuries (53%) were classified as moderate or severe (absence of more than a week), the mean absence per injury being 15 days. Reinjuries accounted for 15% of all registered injuries. In the 2005/6 to 2007/8 seasons, 41% of all diagnoses relied solely on clinical examination.
Hip/groin injuries are common in professional football, and the incidence over consecutive seasons is consistent. Hip/groin injuries are associated with long absences. Many hip/groin diagnoses are based only on clinical examination.
To study the injury characteristics in professional football and to follow the variation of injury incidence during a match, during a season and over consecutive seasons.
Prospective cohort study where teams were followed for seven consecutive seasons. Team medical staff recorded individual player exposure and time-loss injuries from 2001 to 2008.
European professional men's football.
The first team squads of 23 teams selected by the Union of European Football Associations as belonging to the 50 best European teams.
Injury incidence.
4483 injuries occurred during 566 000 h of exposure, giving an injury incidence of 8.0 injuries/1000 h. The injury incidence during matches was higher than in training (27.5 vs 4.1, p<0.0001). A player sustained on average 2.0 injuries per season, and a team with typically 25 players can thus expect about 50 injuries each season. The single most common injury subtype was thigh strain, representing 17% of all injuries. Re-injuries constituted 12% of all injuries, and they caused longer absences than non re-injuries (24 vs 18 days, p<0.0001). The incidence of match injuries showed an increasing injury tendency over time in both the first and second halves (p<0.0001). Traumatic injuries and hamstring strains were more frequent during the competitive season, while overuse injuries were common during the preseason. Training and match injury incidences were stable over the period with no significant differences between seasons.
The training and match injury incidences were stable over seven seasons. The risk of injury increased with time in each half of matches.
Life is full of risky decisions, from mundane ones, to matters of life and death.1 In professional football, risk is everywhere: For the club—the risk of having a poor season and loss of income by not qualifying for an important competition. For the manager—overseeing a bad run of results, potentially jeopardising his position. For the player—poor performance and, of course, injury. For the medical/science team—bringing a player back too early from musculoskeletal injury, and he/she suffering a reinjury. The dilemma is that, usually, riskier options promise higher returns.1
In football, the decision to progress or delay a player's return to play (RTP) after musculoskeletal injury could be the difference between having a key player back two games earlier (giving the best chance to earn six points) contrasted with keeping the player out for two extra games, lowering his/her reinjury risk, but potentially ending up with fewer points. Which risk is more important? Do we aim for a reinjury rate of 0%? Or might we settle for 10% recurrence, where every injured player is back one game earlier?
RTP has been prominent …
Aim:
The present study evaluated whether the MRI parameters of hamstring injuries in male professional football players correlate with time to return to play (RTP).
Methods:
46 elite European football teams were followed prospectively for hamstring injuries between 2007 and 2014. Club medical staff recorded individual player exposure and time-loss after hamstring injury. MRI parameters were evaluated by two independent radiologists and correlated with the RTP data.
Results:
A total of 255 grade 1 and 2 injuries were evaluated in this study. RTP was longer for grade 2 than grade 1 injuries (24±13, 95% CI 21 to 26 days vs 18±15, 95% CI 16 to 20 days; mean difference: 6, 95% CI 2 to 9 days, p=0.004, d=0.39). 84% of injuries affected the biceps femoris (BF) muscle, whereas 12% and 4% affected the semimembranosus (SM) and semitendinosus (ST), respectively. No difference in lay-off time was found for injuries to the three different muscles (BF 20±15 days, SM 18±11 days, ST 23±14 days; p=0.83). The recurrence rate was higher for BF injuries than for SM and ST injuries combined (18% vs 2%, p=0.009). The size of the oedema weakly correlated with time to RTP (r(2)=6-12%). No correlation was found between location of injury and time to RTP. The majority of the intramuscular injuries affected the MT junction (56% in grade 1 and 2 injuries), but no difference in lay-off time was found between the different types of injuries.
Conclusions:
The radiological grade and size of the oedema correlate with time to RTP for both, grade 1 and 2 injuries. No correlations were found between time to RTP and the location and type of injury.
Background Studies investigating the development of ACL injuries over time in football are scarce and more data on what happens before and after return to play (RTP) are needed.
Aim To investigate (1) time trends in ACL injury rates, (2) complication rates before return to match play following ACL reconstruction, and (3) the influence of ACL injury on the subsequent playing career in male professional football players.
Methods 78 clubs were followed between 2001 and 2015. Time trend in ACL injury rate was analysed using linear regression. ACL-injured players were monitored until RTP and tracked for 3 years after RTP.
Results We recorded 157 ACL injuries, 140 total and 17 partial ruptures, with a non-significant average annual increase in the ACL injury rate by 6% (R2=0.13, b=0.059, 95% CI −0.04 to 0.15, p=0.20). The match ACL injury rate was 20-fold higher than the training injury rate (0.340 vs 0.017 per 1000 h). 138 players (98.6%) with a total rupture underwent ACL reconstruction; all 134 players with RTP data (4 players still under rehabilitation) were able to return to training, but 9 of them (6.7%) suffered complications before their first match appearance (5 reruptures and 4 other knee surgeries). The median layoff after ACL reconstruction was 6.6 months to training and 7.4 months to match play. We report 3-year follow-up data for 106 players in total; 91 players (85.8%) were still playing football and 60 of 93 players (65%) with ACL reconstruction for a total rupture played at the same level.
Conclusions The ACL injury rate has not declined during the 2000s and the rerupture rate before return to match play was 4%. The RTP rate within a year after ACL reconstruction was very high, but only two-thirds competed at the highest level 3 years later.
Background Determining fracture risk and rehabilitation periods after specific fractures in professional football is essential for team planning.
Aim To identify fracture epidemiology and absences after different types of fractures in male professional football players.
Methods 2439 players from 41 professional male teams in 10 countries were followed prospectively from 2001 to 2013. Team medical staff registered fractures, absences after fractures and player exposure.
Results 364 fractures were recorded, with an incidence of 0.27/1000 h of exposure (95% CI 0.25 to 0.30). The incidence of traumatic fractures was 0.25 (0.22 to 0.27) and that of stress fractures was 0.03 (0.02 to 0.04). 45% of traumatic fractures and 86% of stress fractures affected the lower extremities. Absence after a fracture was 32 days (1–278) (median (range)), compared to that after a traumatic fracture of 30 days (1–278) and a stress fracture of 65 days (6–168) (p<0.001). Annual fracture incidence was stable during the study period (R2=0.051, b=−0.011 (95% CI −0.043 to 0.021)). Young players had a relative risk of 10.9 (3.3 to 35.6) of sustaining stress fractures compared to old players (p<0.01). The fracture incidence did not differ between individuals in different playing positions (p=0.10).
Summary A male professional football team can expect 1 to 2 fractures per season. There are more traumatic fractures than stress fractures; while most fractures affect the lower extremities, stress fractures yield longer absences than traumatic fractures and young players have more stress fractures than old players. There is no difference in risk among players at different playing positions.
Background Previous injury is a well-documented risk factor for football injury. The time trends and patterns of recurrent injuries at different playing levels are not clear.
Aim To compare recurrent injury proportions, incidences and patterns between different football playing levels, and to study time trends in recurrent injury incidence.
Methods Time-loss injuries were collected from injury surveillance of 43 top-level European professional teams (240 team-seasons), 19 Swedish premier division teams (82 team-seasons) and 10 Swedish amateur teams (10 team-seasons). Recurrent injury was defined as an injury of the same type and at the same site as an index injury within the preceding year, with injury <2 months defined as an early recurrence, and >2 months as a delayed recurrence. Seasonal trend for recurrent injury incidence, expressed as the average annual percentage of change, was analysed using linear regression.
Results 13 050 injuries were included, 2449 (18.8%) being recurrent injuries, with 1944 early (14.9%) and 505 delayed recurrences (3.9%). Recurrence proportions were highest in the second half of the competitive season for all cohorts. Recurrence proportions differed between playing levels, with 35.1% in the amateur cohort, 25.0% in the Swedish elite cohort and 16.6% in the European cohort (χ2 overall effect, p<0.001). A decreasing trend was observed in recurrent injury incidence in the European cohort, a −2.9% average annual change over the 14-year study period (95% CI −5.4% to −0.4%, p=0.026). Similarly, a decreasing tendency was also seen in the Swedish premier division.
Conclusions Recurrence proportions showed an inverse relationship with playing level, and recurrent injury incidence has decreased over the past decade.
Background There are limited data on hamstring injury rates over time in football.
Aim To analyse time trends in hamstring injury rates in male professional footballers over 13 consecutive seasons and to distinguish the relative contribution of training and match injuries.
Methods 36 clubs from 12 European countries were followed between 2001 and 2014. Team medical staff recorded individual player exposure and time-loss injuries. Injuries per 1000 h were compared as a rate ratio (RR) with 95% CI. Injury burden was the number of lay off days per 1000 h. Seasonal trend for injury was analysed using linear regression.
Results A total of 1614 hamstring injuries were recorded; 22% of players sustained at least one hamstring injury during a season. The overall hamstring injury rate over the 13-year period was 1.20 injuries per 1000 h; the match injury rate (4.77) being 9 times higher than the training injury rate (0.51; RR 9.4; 95% CI 8.5 to 10.4). The time-trend analysis showed an annual average 2.3% year on year increase in the total hamstring injury rate over the 13-year period (R2=0.431, b=0.023, 95% CI 0.006 to 0.041, p=0.015). This increase over time was most pronounced for training injuries—these increased by 4.0% per year (R2=0.450, b=0.040, 95% CI 0.011 to 0.070, p=0.012). The average hamstring injury burden was 19.7 days per 1000 h (annual average increase 4.1%) (R2=0.437, b=0.041, 95% CI 0.010 to 0.072, p=0.014).
Conclusions Training-related hamstring injury rates have increased substantially since 2001 but match-related injury rates have remained stable. The challenge is for clubs to reduce training-related hamstring injury rates without impairing match performance.
“When will I be able to play again?” is usually the reflex thought when an athlete suffers an injury. When making return to play decisions, clinicians (including physiotherapists, athletic trainers and physicians) and athletes might engage in a risk–benefit analysis of sorts, consciously or unconsciously weighing up the risks associated with participation and the extent to which those risks can be tolerated.1 ,2 There are a number of questions to contemplate: How does the clinician determine when the athlete is ready to return to play? Is physical recovery alone enough for return to play? What is successful return to play? What are the sports medicine clinician's responsibilities within the team, and to the athlete? Should athletes even return to play?
But what evidence can be used to answer these questions? We highlight some of the complexities in making the return to play decision, and key areas that need to be addressed.
### How does the clinician determine when the athlete is ready to return to play?
In the traditional evidence-based practice model,3 the clinician integrates the best available evidence from research with individual clinical experience and the patient's preferences when making decisions. In the search for the best evidence, considering an ankle sprain, the clinician might consult a textbook, where the evidence says that the athlete should have no pain or swelling, full strength and range of motion, and a healed ligament before returning to full competition.4 The time taken for pain and swelling to subside and full range of motion to return might vary from a couple of weeks to a couple of months; it may take a year for ligament healing.5 But in real life the athlete may return to play within 1 or 2 weeks of …
The sport medicine clinician is faced with return-to-play (RTP) decisions for every patient who wants to return to activity. The complex interaction of factors related to history, physical examination, testing, activity and baseline characteristics can make RTP decision-making challenging. Further, when reasoning is not explicit, unnecessary conflict can arise among clinicians themselves, or among clinicians and patients. This conflict can have negative health consequences for the patient. In 2010, a transparent framework for RTP decisions was proposed. However, some have identified limitations to the framework and found difficulties in its implementation. This paper presents a revised framework that addresses the limitations, and provides concrete examples of how to apply it in simple and complex cases.
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Variations in definitions and methodologies have created differences in the results and conclusions obtained from studies of football (soccer) injuries, making interstudy comparisons difficult. Therefore an Injury Consensus Group was established under the auspices of Fédération Internationale de Football Association Medical Assessment and Research Centre. A nominal group consensus model approach was used. A working document on definitions, methodology, and implementation was discussed by the group. Iterative draft statements were prepared and circulated to members of the group for comment before the final consensus statement was produced. Definitions of injury, recurrent injury, severity, and training and match exposures in football together with criteria for classifying injuries in terms of location, type, diagnosis, and causation are proposed. Proforma for recording players’ baseline information, injuries, and training and match exposures are presented. Recommendations are made on how the incidence of match and training injuries should be reported and a checklist of issues and information that should be included in published reports of studies of football injuries is presented.
Background
The injury risk in football is high, but little is known about causes of injury.
Purpose
To identify risk factors for football injuries using a multivariate model.
Study Design
Prospective cohort study.
Methods
Participants were 306 male football players from the two highest divisions in Iceland. Before the 1999 football season started, the following factors were examined: height, weight, body composition, flexibility, leg extension power, jump height, peak O2 uptake, joint stability, and history of previous injury. Injuries and player exposure were recorded throughout the competitive season.
Results
Older players were at higher risk of injury in general (odds ratio [OR] = 1.1 per year, P = 0.05). For hamstring strains, the significant risk factors were age (OR = 1.4 [1 year], P < 0.001) and previous hamstring strains (OR = 11.6, P < 0.001). For groin strains, the predictor risk factors were previous groin strains (OR = 7.3, P = 0.001) and decreased range of motion in hip abduction (OR = 0.9 [1°], P = 0.05). Previous injury was also identified as a risk factor for knee (OR = 4.6) and ankle sprains (OR = 5.3).
Conclusions
Age and previous injury were identified as the main risk factors for injury among elite football players from Iceland.
The Nordic hamstring (NH) exercise programme was introduced in 2001 and has been shown to reduce the risk of acute hamstring injuries in football by at least 50%. Despite this, the rate of hamstring injuries has not decreased over the past decade in male elite football.
To examine the implementation of the NH exercise programme at the highest level of male football in Europe, the UEFA Champions League (UCL), and to compare this to the Norwegian Premier League, Tippeligaen, where the pioneer research on the NH programme was conducted.
Retrospective survey.
50 professional football teams, 32 from the UCL and 18 from Tippeligaen.
A questionnaire, based on the Reach, Efficacy, Adoption, Implementation and Maintenance framework, addressing key issues related to the implementation of the NH programme during three seasons from 2012 through 2014, was distributed to team medical staff using electronic survey software.
The response rate was 100%. Of the 150 club-seasons covered by the study, the NH programme was completed in full in 16 (10.7%) and in part in an additional 9 (6%) seasons. Consequently, 125 (83.3%) club-seasons were classified as non-compliant. There was no difference in compliance between the UCL and Tippeligaen in any season (χ(2): 0.41 to 0.52).
Adoption and implementation of the NH exercise programme at the highest levels of male football in Europe is low; too low to expect any overall effect on acute hamstring injury rates.
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Background Acute hamstring re-injuries are common and hard to predict. The aim of this study was to investigate the association between clinical and imaging findings and the occurrence of hamstring re-injuries.
Methods We obtained baseline data (clinical and MRI findings) of athletes who sustained an acute hamstring injury within 5 days of initial injury. We also collected data of standardised clinical tests within 7 days after return to play (RTP). The number of re-injuries was recorded within 12 months. We analysed the association between the possible predictive variables and re-injuries with a multivariate Cox proportional-hazards regression model.
Results Eighty patients were included at baseline and 64 patients could be included in the final analysis because data after RTP were not available in 16 cases. There were 17 re-injuries (27%). None of the baseline MRI findings were univariately associated with re-injury. A higher number of previous hamstring injuries (adjusted OR (AOR) 1.33; 95% CI 1.11 to 1.61), more degrees of active knee extension deficit after RTP (AOR 1.13; 95% CI 1.03 to 1.25), isometric knee flexion force deficit at 15° after RTP (AOR 1.04; 95% CI 1.01 to 1.07) and presence of localised discomfort on hamstring palpation after RTP (AOR 3.95; 95% CI 1.38 to 11.37) were significant independent predictors of re-injury. Athletes with localised discomfort on hamstring palpation just after RTP were consequently almost four times more likely to sustain a re-injury.
Conclusions The number of previous hamstring injuries, active knee extension deficit, isometric knee flexion force deficit at 15° and presence of localised discomfort on palpation just after RTP are associated with a higher hamstring re-injury rate. None of the baseline MRI parameters was a predictor of hamstring re-injury.
Trial registration number ClinicalTrial.gov number NCT01812564.
Groin injuries cause major problems in the football codes, as they are prevalent and lead to prolonged symptoms and high recurrence. The aim of the present study was to describe the occurrence and clinical presentation of groin injuries in a large cohort of sub-elite soccer players during a season.
Physiotherapists allocated to each of the participating 44 soccer clubs recorded baseline characteristics and groin injuries sustained by a cohort of 998 sub-elite male soccer players during a full 10-month season. All players with groin injuries were examined using the clinical entity approach, which utilises standardised reproducible examination techniques to identify the injured anatomical structures. The exposure time and the injury time were also recorded. Injury time was analysed using multiple regression on the log of the injury times as the data were highly skewed. Effects are thus reported at relative injury time (RIT).
Adductor-related groin injury was the most common entity found followed by iliopsoas-related and abdominal-related injuries. The dominant leg was significantly more often injured. Age and previous groin injury were significant risk factors for sustaining a groin injury. Groin injuries were generally located on the same side as previously reported groin injuries. Adductor-related injuries with no abdominal pain had significantly longer injury times compared to injuries with no adductor and no abdominal pain (RIT 2.28, 95% CI 1.22 to 4.25, p=0.0096). Having both adductor and abdominal pain also increased the injury time significantly when compared to injuries with no adductor and no abdominal pain (RIT=4.56, 95% CI 1.91 to 10.91, p=0.001).
Adductor-related groin injury was the most common clinical presentation of groin injuries in male soccer players and the cause of long injury time, especially when combined with abdominal-related injury.
Background There is little information about Metatarsal Five (MT-5) fractures for specific sports.
Objective To study the occurrence, the imaging characteristics, the lay-off times and healing problems of MT-5 fractures among male footballers.
Methods Sixty-four European elite teams were monitored from 2001 to 2012. x-Rays were collected and classified by the Torg criteria.
Results Of 13 754 injuries, 0.5% (67) proved to be MT-5 fractures. Their incidence was 0.04 injuries/1000 h of exposure. A team of 25 players might thus expect an MT-5 fracture every fifth season. Of these fractures, 67% (38) were primary and 33% were refractures. One of the 38 primary fractures was an avulsion of the tuberosity; all the others (97%) located towards the base. In total, 32% of the players with MT-5 fracture were younger than 21 years, 40% of the fractures occurred during the preseason and 45% of the players had prodromal symptoms. In total, 54% of the initial x-rays were classified as Torg type II (stress fractures), and 46% were classified as Torg type I (acute type). After surgical treatment the fractures healed faster, compared with conservative treatment (75% vs 33%, p<0.05). There was no significant difference in lay-off days between players that had been operated, and those that had not (80 vs 74 days, p=0.67).
Conclusions The majority of MT-5 fractures are stress fractures, and mainly occur among young players. There are frequent healing problems, which might be explained by the stress nature of the injury. After surgery there are less healing problems, compared with those in conservative treatment.
The aim of this study was to monitor injury incidence and pattern in Norwegian male professional football over six consecutive seasons and compare the risk of injury between the preseason and competitive season. All time loss injuries were recorded by the medical staff of each club. In total, 2365 injuries were recorded. The incidence of acute injuries was 15.9/1000 match hours [95% confidence interval (CI): 14.9-16.8], 1.9/1000 training hours (95% CI: 1.7-2.0), and 1.4 (95% CI: 1.3-1.5) overuse injuries/1000 h. A linear regression model found an annual increase of 1.06 acute match injuries/1000 h (95% CI: 0.40-1.73), corresponding to a total increase of 49% during the 6-year study period. When accounting for interteam variation and clustering effects using a general estimating equation model, the increase in injury incidence was 0.92 (95% CI: -0.11-1.95, P = 0.083). No difference in the risk of acute match injuries (rate ratio (RR): 0.86, 95% CI: 0.73-1.01), acute training injuries (RR: 1.16, 95% CI: 0.99-1.36), or overuse injuries (RR: 1.04, 95% CI: 0.89-1.21) was observed between the preseason and competitive season. In conclusion, the overall risk of acute match injuries in Norwegian male professional football increased by 49% during the study period, although this increase was not fully consistent across teams. We detected no change in the risk of training and overuse injuries or any difference between the preseason and competitive season.
The incidence of acute hamstring injuries is high in several sports, including the different forms of football.
The authors investigated the preventive effect of eccentric strengthening of the hamstring muscles using the Nordic hamstring exercise compared with no additional hamstring exercise on the rate of acute hamstring injuries in male soccer players.
Randomized controlled trial; Level of evidence, 1.
Fifty Danish male professional and amateur soccer teams (942 players) were allocated to an intervention group (461 players) or a control group (481 players). Players in the intervention group conducted a 10-week progressive eccentric training program followed by a weekly seasonal program, whereas players in the control group followed their usual training program. The main outcome measures were numbers of overall, new, and recurrent acute hamstring injuries during 1 full soccer season.
Fifty-two acute hamstring injuries in the control group compared with 15 injuries in the intervention group were registered. Comparing intervention versus the control group, overall acute hamstring injury rates per 100 player seasons were 3.8 versus 13.1 (adjusted rate ratio [RR], 0.293; 95% confidence interval [CI], 0.150-0.572; P < .001). New injury rates per 100 player seasons were 3.1 versus 8.1 (RR, 0.410; 95% CI, 0.180-0.933; P = .034), whereas recurrent injury rates per 100 player seasons were 7.1 versus 45.8 (RR, 0.137; 95% CI, 0.037-0.509; P = .003). Number needed to treat [NNT] to prevent 1 acute hamstring injury (new or recurrent) is 13 (95% CI, 9-23) players. The NNT to prevent 1 new injury is 25 (95% CI, 15-72) players, and NNT to prevent 1 recurrent injury is 3 (95% CI, 2-6) players.
IN male professional and amateur soccer players, additional eccentric hamstring exercise decreased the rate of overall, new, and recurrent acute hamstring injuries.
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.
Overuse injuries may represent as much of a problem as do acute injuries in many sports. This paper reviews key concepts related to the methodology for recording overuse symptoms. Results from the FIVB Volleyball Injury Study were used to compare two different recording methods. The aim of this paper was to provide recommendations on how standardised methodology can be developed to quantify overuse injuries in surveillance studies. Using beach volleyball data, a "traditional" cohort study approach using a time-loss injury definition suggested that injury risk was very low. In contrast, the data from a survey of past and present pain problems in the shoulder, knees and low back demonstrated that these were prevalent. The following recommendations are made: (1) studies should be prospective, with continuous or serial measurements of symptoms; (2) valid and sensitive scoring instruments need to be developed to measure pain and other relevant symptoms; (3) prevalence and not incidence should be used to report injury risk; (4) severity should be measured based on functional level and not time loss from sports. In conclusion, new approaches are needed to develop more appropriate methodology to quantify overuse injuries in studies.
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.
This prospective cohort study was conducted to identify risk factors for acute ankle injuries among male soccer players. A total of 508 players representing 31 amateur teams were tested during the 2004 pre-season through a questionnaire on previous injury and function score (foot and ankle outcome score; FAOS), functional tests (balance tests on the floor and a balance mat) and a clinical examination of the ankle. Generalized estimating equations were used in univariate analyses to identify candidate risk factors, and factors with a P-value <0.10 were then examined in a multivariate model. During the season, 56 acute ankle injuries, affecting 46 legs (43 players), were registered. Univariate analyses identified a history of previous acute ankle injuries [odds ratio (OR) per previous injury: 1.25, 95% confidence interval (CI) 1.09-1.43] and the FAOS sub-score "Pain" (OR for a 10-point difference in score: 0.81, 95% CI 0.62-1.04) as candidate risk factors. In a multivariate analysis, only the number of previous acute ankle injuries proved to be a significant (adjusted OR per previous injury: 1.23; 95% CI 1.06-1.41, P=0.005) predictor of new injuries. Function scores, functional tests and clinical examination could not independently identify players at an increased risk in this study.
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.
To undertake a prospective epidemiological study of the injuries sustained in English professional football over two competitive seasons.
Player injuries were annotated by club medical staff at 91 professional football clubs. A specific injury audit questionnaire was used together with a weekly form that documented each club's current injury status.
A total of 6,030 injuries were reported over the two seasons with an average of 1.3 injuries per player per season. The mean (SD) number of days absent for each injury was 24.2 (40.2), with 78% of the injuries leading to a minimum of one competitive match being missed. The injury incidence varied throughout the season, with training injuries peaking during July (p<0.05) and match injuries peaking during August (p<0.05). Competition injuries represented 63% of those reported, significantly (p<0.01) more of these injuries occurring towards the end of both halves. Strains (37%) and sprains (19%) were the major injury types, the lower extremity being the site of 87% of the injuries reported. Most injury mechanisms were classified as being non-contact (58%). Re-injuries accounted for 7% of all injuries, 66% of these being classified as either a strain or a sprain. The severity of re-injuries was greater than the initial injury (p<0.01).
Professional football players are exposed to a high risk of injury and there is a need to investigate ways of reducing this risk. Areas that warrant attention include the training programmes implemented by clubs during various stages of the season, the factors contributing to the pattern of injuries during matches with respect to time, and the rehabilitation protocols employed by clubs.
To conduct a detailed analysis of ankle sprains sustained in English professional football over two competitive seasons.
Club medical staff at 91 professional football clubs annotated player injuries. A specific injury audit questionnaire was used together with a weekly form that documented each club's current injury status.
Completed injury records for the two competitive seasons were obtained from 87% and 76% of the participating clubs. Ankle ligament sprains accounted for 11% of the total injuries over the two seasons, with over three quarters (77%) of sprains involving the lateral ligament complex. A total of 12 138 days and 2033 matches were missed because of ankle sprains. More sprains were caused by contact mechanisms than non-contact mechanisms (59% v 39%) except in goalkeepers who sustained more non-contact sprains (21% v 79%, p<0.01). Ankle sprains were most often observed during tackles (54%). More ankle sprains were sustained in matches than in training (66% v 33%), with nearly half (48%) observed during the last third of each half of matches. A total of 44% of sprains occurred during the first three months of the season. A high number of players (32%) who sustained ankle sprains were wearing some form of external support. The recurrence rate for ankle sprains was 9% (see methodology for definition of reinjury).
Ankle ligament sprains are common in football usually involving the lateral ligament complex. The high rate of occurrence and recurrence indicates that prevention is of paramount importance.