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Purpose: Injuries are a common occurrence in football. Sufficient epidemiological data are available in professional football but not in salaried semi-professional football. This study investigates the injury incidence at different levels of semi-professional football with focus on junior football. Methods: The data were based on injury reports provided by players and medical staff over the 2015-2016 season, which corresponded to the consensus statement for data samples in football. This study investigated the injury incidence and prevalence of five skill levels of semi-professional football (the fourth to the seventh league and elite junior football). Results: 1130 players had sustained 2630 injuries over the 2015-2016 season. The overall injury incidence was 9.7 per 1000 h football exposure; prevalence with at least one injury was 79%. The highest overall injury incidence in elite junior football was 10.4 in 1000 h football exposure. The fifth league had the lowest incidence with 9.0 in 1000 h football (p < 0.05). Traumatic injuries most often occurred in the fourth league (3.9 in 1000 h football). The body areas most affected by traumatic injury were knees, ankles and thighs. Elite junior players had a significantly higher incidence of overuse complaints (7.4 in 1000 h football) than the fourth league (5.4, p = 0.005). The body areas most affected by overuse complaints were the lower back, thigh and groin. No differences were found between the different positions on field. Conclusions: Salaried semi-professional football involves a high overall injury incidence. The highest incidence, particularly of overuse injuries, was seen in elite junior football. These findings should be incorporated in specific injury prevention training or screenings beginning in junior football. Level of evidence II.
1 3
Knee Surgery, Sports Traumatology, Arthroscopy
Injury incidence insemi-professional football claims forincreased
need ofinjury prevention inelite junior football
OliverLoose1· BirgitFellner2· JenniferLehmann2· LeonardAchenbach3· VolkerKrutsch4· StephanGerling5·
PetraJansen2· PeterAngele3· MichaelNerlich3· WernerKrutsch3
Received: 30 March 2018 / Accepted: 14 August 2018
© European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2018
Purpose Injuries are a common occurrence in football. Sucient epidemiological data are available in professional foot-
ball but not in salaried semi-professional football. This study investigates the injury incidence at dierent levels of semi-
professional football with focus on junior football.
Methods The data were based on injury reports provided by players and medical sta over the 2015–2016 season, which
corresponded to the consensus statement for data samples in football. This study investigated the injury incidence and preva-
lence of five skill levels of semi-professional football (the fourth to the seventh league and elite junior football).
Results 1130 players had sustained 2630 injuries over the 2015–2016 season. The overall injury incidence was 9.7 per 1000h
football exposure; prevalence with at least one injury was 79%. The highest overall injury incidence in elite junior football
was 10.4 in 1000h football exposure. The fifth league had the lowest incidence with 9.0 in 1000h football (p < 0.05). Trau-
matic injuries most often occurred in the fourth league (3.9 in 1000h football). The body areas most aected by traumatic
injury were knees, ankles and thighs. Elite junior players had a significantly higher incidence of overuse complaints (7.4 in
1000h football) than the fourth league (5.4, p = 0.005). The body areas most aected by overuse complaints were the lower
back, thigh and groin. No dierences were found between the dierent positions on field.
Conclusions Salaried semi-professional football involves a high overall injury incidence. The highest incidence, particularly
of overuse injuries, was seen in elite junior football. These findings should be incorporated in specific injury prevention
training or screenings beginning in junior football.
Level of evidence II.
Keywords Injury· Incidence· Elite football· Soccer· Salary· Prevention
The popularity of football around the world is ever increas-
ing, and over 200million players make football the number
one sports worldwide [6]. However, playing football also
involves a high risk of injury; thus, football is one of the
team sports with the highest rate of injury [6, 7]. Injury
incidence in football has been thoroughly investigated with
regard to gender dierences [15, 23]; age-related dierences
have also been found in junior [20, 29, 30] and elderly foot-
ball players [16, 17].
The literature includes many publications on injuries
of professional and amateur football players in dierent
countries, which showed considerable dierences between
the various skill levels [1, 2, 11, 26, 31]. Various countries
have published their respective overall injury incidences
* Werner Krutsch
1 Clinic ofPaediatric Surgery, Clinic St. Hedwig Regensburg,
Regensburg, Germany
2 Institute ofSport Science, University ofRegensburg,
Regensburg, Germany
3 Department ofTrauma Surgery, University Medical Centre
Regensburg, Regensburg, Germany
4 Department ofOtorhinolaryngology, Paracelsus Medical
University Nuremberg, Nuremberg, Germany
5 Clinic ofPediatric andAdolescent Medicine, St. Hedwig
Clinic, Regensburg, Germany
Knee Surgery, Sports Traumatology, Arthroscopy
1 3
in professional football, for instance, Sweden (training
4.7/1000h, match 28.1/1000h) [15] and Spain (training
3.8/1000h, match 38.8/1000h) [28], as well as the dier-
ences between the various professional football leagues.
Injuries in the first league are reported, just the same as the
rates of the second or third professional leagues [3, 22, 35].
The scientific seasonal reports of the UEFA Champions
League show an overall incidence of 7.6 injuries in 1000h
(training 4.0/1000h, match 26.7/1000h) [5, 9, 36, 38]. The
injury incidence in professional football tournaments of
the FIFA World Championship and the UEFA European
Championship is 68.7 per 1000h [8, 18, 37]. In the foot-
ball tournament of the Olympic Games in 2012, 509 players
sustained 179 (35.2%) injuries [10]. Additionally, profes-
sional junior football players show an injury incidence of
3.8/1000h during training sessions and of 14.2/1000h dur-
ing match exposure [30].
Injury incidences in amateur football are also recently
published, for both tournaments and seasonal settings [24,
34]. Amateur football tournaments show incidence rates of
80.7/1000h [19], whereas seasonal injury reports show an
overall incidence of 9.6/1000h (training 3.9/1000h, match
20.4/1000h) [33]. Injury incidences of 2.1/1000h in train-
ing sessions and 14.2/1000h in matches have been reported
in amateur junior football [27].
Consecutively, every setting in seasonal or tournament
football shows a similar trend but a specific injury incidence,
based on the characteristics of the competitions. Such injury
incidences in dierent football subpopulations represent the
risk of injury of a player in the respective setting. Therefore,
the risk of injury should be investigated for each individual
setting and football subpopulation to develop suitable injury
prevention strategies. However, the injury patterns of one
large subpopulation in football have been hardly investi-
gated. The biggest and most developed football countries
have established a comprehensive structure of football
leagues: Besides the traditional professional football levels
with salaried licenced players on the one hand, and ama-
teur or recreational football players, on the other hand; such
countries also have intermediate elite levels with salaried
semi-professional football players [12]. Such semi-profes-
sional football leagues have specific settings and conditions
with regard to training, salary, team coach education, expec-
tations and requirements of players or medical equipment
and sta [25]. Injury incidences in these semi-professional
settings are not published in detail in the literature. Espe-
cially in German football, epidemiological injury reports
(Fig.1) are only available in professional [3, 11, 22], ama-
teur and junior football [17, 19, 20]. This study investigated
the injury incidence in semi-professional football leagues
as well as the question, if elite junior football players in a
semi-professional setting have a higher risk of injuries than
players in other settings. Hypothesis of this study is that
because of the increasing requirements and professionalism
in semi-professional salaried football, mainly the youngest
players have the highest risk of injury.
Materials andmethods
All participants of this prospective controlled cohort study
(level of evidence: II) received detailed information about
the study design and the pseudonymised questionnaire.
Informed consent was obtained from every participant.
The study was approved by the Ethics Committee of the
University of Regensburg (Number: 15-101-0137). An epi-
demiological injury analysis was conducted in this study
in the fourth to seventh league and the highest elite junior
divisions—which represent semi-professional elite football
in Germany—during the 2015–2016 football season. The
semi-professional football level in Germany includes foot-
ball players with a profession outside football. However,
playing football on a salaried level involves severe physical
demands and a high frequency of training sessions. These
football levels are not represented in all European countries
but show specific properties and place physical and psycho-
logical demands on the players. Therefore, semi-professional
football needs to be dierentiated from traditional amateur
and professional football (Table1; Fig.1).
This study is part of a large research project to improve
preventive strategies in elite football. The complete study
population consisted of 62 teams with 1527 players.
Launched by the public trauma insurance for professional
athletes in Germany (Verwaltungsberufsgenossenschaft
VBG), this project started a multimodal approach to improve
injury prevention strategies in semi-professional football.
Besides a team coach analysis regarding the current status
of injury prevention at this football level [25], this epidemio-
logical injury investigation of the dierent semi-professional
football leagues provided a basis to understand injury inci-
dence and the main injury problems at this football level.
Further steps after this epidemiological injury investigation
may be the implementation of training modules for injury
prevention or of screening examinations to evaluate the
individual risk factors of each player at this level. All play-
ers who accepted to participate in this study were included
if they had played a minimum of one match during the
2015–2016 season. Players who had no ocial match dur-
ing that season were excluded. Players and teams without
any continuous documentation over the season were also
excluded as well as players who had left their clubs during
the season.
Data collection was based on the injury statistics of the
participating players analysed by means of a self-adminis-
tered questionnaire for personal data and on the mid-season
injury report provided by the medical sta (team doctor/
Knee Surgery, Sports Traumatology, Arthroscopy
1 3
physiotherapist). Injury data and football exposure were doc-
umented and sent to the study coordinator. The questionnaire
contained anthropometric data, football-specific data such as
football exposure and injury data, for instance, the type of
injury or the injured body area. Data collection and injury
definition corresponded to the consensus statement on injury
definitions and epidemiological data collection procedures
in football [13, 14] and to previous epidemiological research
projects in football of the study group [19, 20, 22].
Each traumatic injury was classified either as time-loss
or as non-time-loss injury. Every injury that disallowed the
player to participate in training sessions or matches was cat-
egorised as time-loss injury and counted towards the total
number of injuries. Assuming that semi-professional foot-
ball involves a high rate of overuse injuries, in part without
any time-loss, we analysed overuse injuries separately. All
overuse injuries were documented and investigated both as
time-loss and non-time-loss injuries. Overuse injuries were
injuries without any specific trauma mechanism. Each injury
was analysed regarding the aected body area and the spe-
cific injury mechanism. The injury incidence was calculated
according to the consensus statement as injuries in 1.000h
of football exposure per player [13, 14]; the overall incidence
was the sum of traumatic and overuse injury incidences.
Statistical analysis
For this study, no formal sample size calculation was needed,
because the study design and the customer of this study
planned from the beginning of the study an invitation of all
teams in each of 5 divisions (86 teams) of the semi-profes-
sional football level in the regional German Football Asso-
ciation of Bayern. The number of participants depended on
the number of players of the teams taking part in this study.
Continuous data are expressed as mean and standard devia-
tion (SD). Categorical data are shown as frequency counts
(percentages). To compare two groups, the Fisher’s exact test
Fig. 1 Overview of the semi-professional football and the lack of epidemiological injury reports in national (German) football
Table 1 Characteristics of semi-professional football in Germany
Criteria for semi-professional football
Salaried players and coaches
Compulsory public trauma insurance for traumatic injuries
Minimum of three training sessions per week
Profession outside football
Qualified team coach (coach licence A or B from the German Foot-
ball Association)
Knee Surgery, Sports Traumatology, Arthroscopy
1 3
was used. Continuous data were compared by means of the t
test. To show incidence rates, we used an exact test based on
the Poisson distribution. Odds ratios and rate ratios accom-
panied by the corresponding 95% confidence interval (CI)
are shown as eect estimates. The level of significance was
set to p < 0.05 and high significance to p < 0.01. All analyses
were conducted using IBM SPSS Statistics, version 24.
1130 players of 62 teams were included in this study, 14
teams declined the invitation. 397 (35.1%) dropped out
because of incomplete injury reports or changing of the
team. The mean age of players in semi-professional football
was 23.1years (SD: 4.4). 2630 injuries were documented
over the 2015–2016 season. Training exposure of the over-
all population was 58,013.4h during the season, match
exposure was 270,855h. The overall injury incidence in
semi-professional football in this study was 9.7 per 1000h
football exposure (training 4.5/1000h, match 27.1/1000h).
The overall injury incidence was highest in the elite jun-
ior leagues (10.4) and lowest in the fifth division (9.0, n.s.;
Fig.2). The overall prevalence with at least one injury per
season was 79%.
Traumatic injuries were mostly seen in the highest league
of semi-professional football, i.e. in the fourth division (3.9),
without any dierence to other subpopulations (n.s., Fig.3).
Semi-professional football showed a high incidence of over-
use injuries, the highest incidence in elite junior football
(7.4), which diered significantly to the lowest incidence in
the fourth division (5.4; p = 0.005; Fig.4).
The body areas most aected by traumatic injuries in this
study population were the thighs (18.2%), knees (18.5%)
and ankles (16.2%; Table2). Overuse injuries occurred most
commonly on the back and trunk (18%) and on the hip or
groin (16%; Table3).
One important finding of this study is the high incidence
of injuries in the dierent divisions of semi-professional
football, which has been investigated in detail for the first
time. The overall incidence of traumatic injuries or overall
injuries at semi-professional football levels investigated in
Fig. 2 Overall injury incidence in semi-professional football leagues Fig. 3 Incidence of traumatic injuries
Fig. 4 Incidence of overuse injuries
Table 2 Body regions aected by traumatic injuries (n = 996)
Body localisation Percentage of
traumatic injuries in
n (%)
Head and neck 38 (3.8)
Upper extremity 90 (9.0)
Back or trunk 66 (6.6)
Hip or groin 156 (15.7)
Thigh 181 (18.2)
Knee 184 (18.5)
Shin 48 (4.8)
Ankle 161 (16.2)
Foot 71 (7.2)
Knee Surgery, Sports Traumatology, Arthroscopy
1 3
this study is higher than that documented in international
seasonal injury reports of professional football [15, 28].
In addition, the comparison of the injury incidence with
that of national professional football in Germany [3, 22]
yielded similar results, confirming the hypothesis of this
study that semi-professional football has specific injury
incidences as a result of the specific demands at this skill
The results of this study represent the largest epidemio-
logical data sample on injuries below the level of profes-
sional football worldwide. Another injury report of semi-
professional football in Ireland also showed a rather high
injury incidence of 9.2 [12]. An important dierence in
semi-professional football to professional football is the
medical service in the case of injury. Motivation and physi-
cal requirements of semi-professional football players do
not significantly dier from those of professional players.
However, the dierent settings of semi-professional players
have a high impact on the incidence and particularly on the
outcome of injuries. The medical service provided in foot-
ball leagues below the professional divisions is traditionally
less extensive and of poorer quality [20], which also aects
prevention, regeneration and treatment strategies as well as
adequate return-to-play strategies. All these factors have a
high impact on the occurrence and outcome of injuries and
re-injuries [20, 25].
Another important finding of this study is the signifi-
cantly higher injury load in junior than in adult players at
elite semi-professional football levels. Junior players nor-
mally show a lower rate of injury than adults [20, 29]. This
study showed that the skill level of players with its respec-
tive physical and psychological requirements is an important
reason for the high injury incidence of junior players. The
incidence of overuse injuries in junior players is an alarming
sign, particularly in comparison to semi-professional adult
football players in this study. This incidence is an important
reason why injury prevention strategies need to be imple-
mented at the junior age levels. At the skill and age level of
elite junior football players, reasons for overuse injuries are
typically tight time schedules over the seasons, insucient
regeneration, high but imbalanced motivation or psychologi-
cal factors due to age or the level of education at school.
Strategies for preventing overuse injuries at this age level
should consider the above-mentioned factors and well-bal-
anced training programmes. Injury prevention programmes
in junior football have been well-reported in the literature
[4, 31] but mainly for lower age groups and skill levels.
Evidence-based prevention strategies in elite junior foot-
ball are missing. The growth of musculoskeletal structures
as well as environmental factors outside the sports during
this vulnerable phase of life is the main reason why junior
players at higher age levels require dierent injury preven-
tion strategies. Another reason and a potential explanation
of the higher injury incidence of elite junior players is the
typically lower compliance regarding recommendations by
adults or team coaches. Equally important to lowering the
physical and psychological load in elite junior football play-
ers is structuring the daily and seasonal football schedule.
The daily schedule should be organised with regard to the
demands of school and education but also needs to leave
time for activities outside football. The seasonal schedule of
talented and elite junior players is filled with club football
but also with competitions and courses oered to the most
talented players by football associations. Close communica-
tion among the responsible people around junior players is
required to coordinate stress and rest for the players. At this
vulnerable age, a comfortable home situation is also funda-
mental for playing football successfully and for preventing
Injury prevention in football is fundamentally based
on detailed knowledge about sufficiently investigated
influencing factors on injuries [1, 2]. The development
of structured injury prevention strategies is only possi-
ble with profound knowledge about the risk of injury, the
mainly aected body areas and the origin and mechanism
of injuries at the investigated football level. On the one
hand, this study shows a need for prevention of injuries
to the lower extremities at semi-professional football lev-
els that is similar to all other skill levels. Evident injury
prevention strategies addressing the lower extremities
are well-published for dierent skill levels and mainly
include active injury prevention through specific exercises
or warm-up programmes [4, 26]. On the other hand, the
profile of overuse injuries in this study population peaks
in complaints of the trunk, in particular of the lower back
and the groin. Available injury prevention strategies for
these types of injury consist of strengthening the muscles
in the trunk and the lower extremities and of improving the
flexibility of the aected and neighbouring joints [21, 32].
Successful prevention of such overuse injuries therefore
requires a well-balanced strategy between strengthening
Table 3 Body regions aected by overuse injuries (n = 1634)
Body localisation Percentage of over-
use injuries in n (%)
Head and neck 167 (10.2)
Upper extremity 154 (9.4)
Back or trunk 291 (17.8)
Hip or groin 255 (15.6)
Thigh 247 (15.1)
Knee 185 (11.3)
Shin 161 (9.9)
Ankle 109 (6.7)
Foot 65 (4.0)
Knee Surgery, Sports Traumatology, Arthroscopy
1 3
and stretching but also between physical load and regen-
eration. Such balance significantly depends on the qual-
ity of education and the number of stas supporting the
players. In this respect, professional football players are
in a significantly better position than semi-professional or
junior players.
This study provides an overview of the incidence and
prevalence of injuries for the practical routine in semi-
professional football. Such knowledge may guide injury
prevention strategies at these football levels. The study
also shows the importance of preventing not only trau-
matic but particularly the much more frequent overuse
injuries through sucient concepts. This finding repre-
sents an important guideline for football clubs and football
associations when dealing with semi-professional football
players. For daily routines in football, is it essential to start
injury prevention strategies already in junior football?
This study also has some limitations. One limitation is
the dropout rate of participants. Compliance with a strict
scientific study design is dicult, even more so in a semi-
professional football setting than at professional levels. A
strong point of this study is its prospective design and the
detailed investigation of dierent football leagues with a
high number of participants. Randomisation of the dier-
ent subpopulations was not possible.
This study on salaried elite semi-professional football
showed a high incidence of injury. The highest overuse
injury incidence was seen in elite junior football. These
findings should be incorporated in injury prevention strate-
gies, which should start in junior football levels.
Acknowledgements Many thanks to the Verwaltungsberufsgenossen-
schaft VBG, to Dr. Patrick Luig, Christian Klein and Hendrik Bloch for
their support and the funding of this study. Many thanks also to Gunnar
Huppertz, Monika Schoell and Florian Zeman of the Centre for Clinical
Studies Regensburg. Thanks also to the participating players and team
coaches of the salaried elite football in Germany.
Funding This study was funded by the Public Trauma Insurance for
salaried athletes in Germany, Verwaltungsberufsgenossenschaft VBG.
Conflict of interest The authors declare that there is no conflict of in-
Ethical approval The study was approved by the Ethics Committee of
the University of Regensburg (Number: 15-101-0137).
Informed consent Informed consent was obtained from every partici-
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... No data on the training exposure of individual players or teams were available in this registry. Training exposure was therefore calculated by means of literature reviews and the personal experience of the authors from previous studies of all football levels [1,12,14,19,21,22]. Prevalence was defined as the proportion of injuries within the total population. ...
... Information documented in this ACL registry is league-specific injury incidences, sports-specific injury mechanisms and risk factors for ACL injuries, which are less frequently recorded in other registries. In contrast to other time-limited study projects on ACL injuries over one season [16,19,22], this ACL registry provides prospective and longitudinal injury data over more than one season, thus representing an adequate basis for trends regarding the occurrence of ACL injuries in all levels of play. This study provides data on the difference in the incidence of ACL injuries between professional, semi-professional and amateur football in Germany. ...
... Amateur football was found to have the highest incidence of ACL injuries and therefore the highest need of injury prevention strategies. The general lack of adequate injury prevention strategies in amateur football may be due to the ignorance of the importance of prevention exercises as well as the lower level of education of the coaching staff and the lower pro-activeness of players at amateur levels a reason for higher rates of incidence in these classes [22]. This study also shows differences in the incidence of ACL injuries between the three professional levels of play, i.e. a trend towards a lower incidence in the 1st and 2nd league than in the 3rd league, which may be a sign for the higher professionalism in implementing prevention strategies in the two highest leagues. ...
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Purpose Anterior cruciate ligament (ACL) injuries are a common severe type of football injury at all levels of play. A football-specific ACL registry providing both prospective ACL injury data according to the skill level and risk factors for ACL injury is lacking in the literature. Methods This study is based on the prospective ‘ACL registry in German Football’ implemented in the 2014–15 season. Professional (1st–3rd league), semi-professional (4th–6th league) and amateur leagues (7th league) were analysed regarding the incidence and risk factors for ACL injuries. Injuries were registered according to the direct reports of the injured players to the study office and double-checked via media analysis. After injury registration, the players received a standardised questionnaire. Data were analysed from the 2014–15 to the 2018–19 football season. Results Overall, 958 ACL injuries were registered during the 5-year study period. The incidence of ACL injuries was highest in amateur football (0.074/1000 h football exposure) compared to professional (0.058/1000 h; p < 0.0001) and semi-professional football (0.043/1000 h; p < 0.0001). At all skill levels, match incidence (professional: 0.343; semi-professional: 0.249; amateur: 0.319) was significantly higher than training incidence (professional: 0.015; semi-professional: 0.004; amateur: 0.005). Major risk factors were previous ACL injury (mean: 23.3%), other knee injuries (mean: 19.3%) and move to a higher league (mean: 24.2%). Conclusion This sports-specific ACL registry provides detailed information on the incidence and risk factors for ACL injuries in football over five years. Risk factors are skill level, match exposure, move to a higher league and previous knee injury. These factors offer potential starting points for screening at-risk players and applying targeted prevention. Level of evidence II.
... After the registration of a new ACL injury either through direct notification by the players or clubs or by online registration, a standardised questionnaire in digital or paper form was sent to the injured player or the responsible team member ( Figure 2). The injury report for this study was adapted to the commonly used injury report protocol in football established by Fuller et al (2006) and previous epidemiological injury studies of this study group (Fuller et al. 2006(Fuller et al. , 2007Koch et al. 2016;Achenbach et al. 2018;Loose et al. 2018Loose et al. , 2019Ekstrand et al. 2020;Krutsch et al. 2020aKrutsch et al. , 2020bKrutsch et al. , 2020cSzymski et al. 2021). ...
... Data on the training exposure of individual players or teams were not available in this registry. Training exposure was therefore calculated by means of literature reviews and the personal experience of the authors from previous studies at all football levels of the same leagues (Koch et al. 2016;Krutsch et al. 2016Krutsch et al. , 2020bLoose et al. 2018Loose et al. , 2019. Prevalence was defined as the proportion of injuries within the total population. ...
... This method has been previously scientifically discussed and published by Krutsch et al (2020) for media reports in professional football and can also be applied to other skill levels and types of sports (Krutsch et al. 2020b;Szymski et al. 2021). Another important issue and limitation of this study is the determination of training exposure using references from the same leagues and divisions published by this study group (Koch et al. 2016;Achenbach et al. 2018;Loose et al. 2018Loose et al. , 2019Ekstrand et al. 2020;Krutsch et al. 2020aKrutsch et al. , 2020bKrutsch et al. , 2020cSzymski et al. 2021). Although these publications refer to the same leagues in Germany, individual differences of ACL injured players are not considered and generalization of training exposure was obtained here. ...
Purpose: Anterior cruciate ligament (ACL) injuries are a common severe type of football injury. Injury prevention measures should be adapted to the respective type of sports and be based on sports-specific strategies. A football-specific ACL registry including prospective ACL injury data of both sexes and at different skill levels is lacking in the literature. Methods: In Germany, a prospective 'ACL registry for German Football' was implemented in the 2014-15 football season. Professional football leagues (1st to 3rd national league), semi-professional football leagues (4th until 6th leagues) and amateur football leagues (7th league and below) were monitored regarding the incidence of ACL injuries, risk factors, general treatment and rehabilitation. After the registration of an injury, injured players were sent a standardised questionnaire. Results: Overall, 1,206 ACL ruptures were registered in the investigated population of more than 56,000 players, resulting in a prevalence of 2.1%. The highest prevalence was found in men's amateur football (2.7%) as well as in men's and women's professional football (2.1% each). Conclusion: This football-specific ACL registry provides for the first-time longitudinal data about ACL injury patterns and treatment at all football levels. This report describes the considerations for data collection and presents first epidemiological results of 6 years of ACL injury registration.
... It is not permitted to frame or use framing techniques to enclose any trademark, logo, or other proprietary information of the Publisher. 4,13 Sulla base alle nostre conoscenze, questo è il primo studio finora che analizza i profili infortunistici dei calciatori della massima serie turca per due campionati consecutivi, in accordo con la definizione consensuale di infortunio e la raccolta dei dati per i calciatori profesionisti. 10 The proportions of different injury locations, the distribution of injuries according to their severity or the distribution of different injury types did not show any significant difference among seasons (P>0.05). ...
... Differences in level of competition, as well as geographical regions, result in various injury rates and profiles in elite football. 4,13 This is the first study to our knowledge to report the injury profile of a Turkish Super League team for two full seasons in compliance with the consensus on injury definitions and data collections in elite football. 10 The team played 54 and 62 matches in two consecutive seasons, whereas teams in the UEFA Elite Club Study played an average of 60 matches in one season. ...
BACKGROUND: Injury profiles of football teams vary according to the level of competition and geographical region. However, there is so far no available injury surveillance data from the Turkish Super League. The aim of this study was to provide a two-season-long, detailed injury profile (injury rate, injury locations, injury severity and injury burden) of an elite Turkish Super League team, which also joined the UEFA Europa League in the second season and to make a comparison of the two seasons. METHODS: Injury records of a Turkish Super League team were kept for two consecutive seasons (2015-2016 and 2016-2017). Injury rates (overall, training and match), types, locations, severity, and burden were analyzed. RESULTS: Rate of injury per 1000h was 6.45 in 2015-2016, and 6.62 in 2016-2017 (P>0.05). Total injury burden per 1000h increased by 42.87% (from 38.74 in 2015-2016 to 55.35 in 2016-2017). Match injury burden was 61.72 in 2015-2016, and 117.56 in 2016-2017, increasing by 90.47%. Injuries to the lower limbs were the most common in both seasons. CONCLUSIONS: Important differences were observed in injury rates and burden in comparison with other leagues from different countries. Also, team injury burden increased dramatically in the second season.
... Noteworthy is that, while there is a quite exhaustive spectrum of papers regarding injuries in professional soccer, for semi-professional and amateur soccer the number of studies is very low, and the main results show significant differences based on the level of skills, age, and country of the subjects 22 . The primary complication in finding a common epidemiological index for semi-professional soccer is represented by the different intercountry characteristics in terms of training, club expectations, medical staff, technical staff, and materials available. ...
... Given the economic and competitive implication associated with the withdrawn of a player 10,19 , is very important to know the epidemiology of injuries and how long it takes to recover from them. However, most of these studies only deal with a portion of this sports, namely professional soccer, and there are not many indications for semi-professional and amateur soccer, despite a large number of players and practitioners 22 . ...
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Background: Soccer is one of the most popular sports in the world involving about 200 million athletes. Injury management in soccer is crucial for performance and for the costs related to rehabilitation and absence from official matches. While there is quite an exhaustive literature regarding injuries in professional soccer, for amateur soccer the incidence of injuries remains unknown. The purpose of this study was to analyse the prevalence of injuries in the fourth Italian soccer division during the competitive season. Methods: Medical staff completed an injury report every two months during the competitive season of the fourth Italian soccer division (14 teams, n = 278). The specific description of the problem, player field-position, number of training losses and number of match losses were collected for each player. The time periods were September/October (T1) November/December (T2), January/February (T3). Results: A significant association between injury type and the period of the season was observed: muscle and tendon injuries were the most prevalent injury type (48.9 %) in all three periods (χ2 (10) = 33.86, p < 0.001). Overall, 108 (39.7 %) injuries occurred at T1, 90 (33.1 %) at T2 and 74 (27.2 %) at T3 (χ2 (12) = 20.32, p = 0.071). Conclusions: Coaches and athletic trainers should be aware of this greater injury risk when preparing a training program for the season, to implement injury prevention protocols for the most prevalent injury types.
... The overall prevalence of unclassified gradual-onset knee injuries was 4 % (95 % CI 2 % to 7 %, I 2 = 96 %; Fig. 2). 35,36,[38][39][40][41][42]46,47,50,51,[53][54][55][56]60,64,69,70,76,77,79 Following subgrouping by sex, male athlete injury prevalence (6 %; 95 % CI 3 % to 9 %, I 2 = 96 %) was higher than female athletes (1 %; 95 % CI 0 % to 5 %, I 2 = 91 %; Appendix D, Fig. 1). Following subgrouping by sport, injury prevalence in soccer (5 %; 95 % CI 2 % to 10 %, I 2 = 96 %) was higher than in rugby union (0 %; 95 % CI 0 % to 2 %, I 2 = 96 %; Appendix D, Fig. 2). ...
Objectives To systematically evaluate the literature and estimate the prevalence, incidence, and burden of gradual-onset knee injuries in team ball-sports. Design Systematic review with meta-analysis. Method Six databases (MEDLINE, EMBASE, Web of Science, CINAHL, SPORTDiscus, SCOPUS) were searched from inception to June 2021. Cohort studies of team ball-sports reporting the number of gradual-onset knee injuries were included. Study quality was assessed using a modified Newcastle-Ottawa scale. Studies were pooled using a Freeman-Tukey Double arcsine transformation (prevalence) and a Poisson random effects regression model (incidence, burden). Results Forty-nine studies that captured gradual-onset knee injuries (unclassified, patellofemoral pain, tendinopathies, and iliotibial band friction syndrome) across 15 team ball-sports were included. For unclassified gradual-onset knee injuries, prevalence was 4 % (95 % Confidence Interval (CI) 2 % to 7 %, I² = 96 %), incidence was 0.32 per 1000 player-hours (95 % CI 0.25 to 0.43, I² = 88 %), and burden was 3.24 days lost per 1000 player-hours (95 % CI 1.95 to 5.37, I² = 99 %). For patellofemoral pain, prevalence was 6 % (95 % CI 1 % to 13 %, I² = 93 %), and incidence was 0.07 per 1000 player-hours (95 % CI 0.04 to 0.12, I² = 67 %). For tendinopathies, prevalence was 1 % (95 % CI 0 % to 2 %, I² = 68 %), incidence was 0.07 per 1000 player-hours (95 % CI 0.04 to 0.11, I² = 76 %), and burden was 2.14 days lost per 1000 player-hours (95 % CI 1.23 to 3.71, I² = 92 %). Conclusion Estimates of prevalence, incidence and burden generated from this systematic review quantify the extent of gradual-onset knee injuries in team ball-sports. Further research is required to assess whether age, sport, and participation level are predictors of gradual-onset knee injuries.
... The injury reports for this study were adapted according to the commonly used injury report protocol in football established by Fuller et al (2006) and according to previous epidemiological injury studies of this study group [7,14,17,25]. ...
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Purpose ACL injuries are one of the most severe injuries in football, but medical consequences and performance outcomes after return to competition are only rarely investigated. Aim of this study was to analyse the time of return to competition (RTC) in German professional, semi-professional and amateur football. Also, this investigation highlights the rate of career ending and performance outcome after RTC in different playing levels by the measurement of playing level, performed matches and played minutes. Methods Database of this investigation is the ‘ACL registry in German Football’ with prospectively collected injury data. Between 2014 and 2018, four seasons in professional (1st–3rd league), semi-professional (4th–6th league) and amateur leagues (7th league) were analysed regarding the return to competition period and performance parameters. Data were collected for three subsequent seasons after injury and compared with the pre-injury and injury season. Data collection was performed using standardized methods. Results A total of 607 ACL injuries were registered during the 4-year period with a mean RTC time of 337.1 day (SD: 183). After primary ACL ruptures, the fastest RTC was found in professional football (247.3 days), while in semi-professional (333.5 d; p < 0.0001) and amateur football (376.2 d; p < 0.0001) a prolonged absence was detected. Re-ruptures occurred in 17.8% ( n = 108) and showed similar trend with fastest RTC in professionals (289.9 days; p = 0.002). Within the first three seasons after injury, 92 players (36.7%) in semi-professional and 24 (20%) in professionals had to end their career. Keeping the level of play was only possible for 48 (47.5%) of professionals, while only 47 (29.6%) of semi-professionals and 43 (28.1%) of amateurs were able to. Only in professional football, no significant difference could be seen in the played minutes and games after 2 years compared to the pre-injury season. Conclusion Lower playing levels and re-ruptures are the main factors for a prolonged return to competition after ACL rupture in German football. Significant reduction in playing level and a high rate of career endings were found for all levels of play. However, only professional players were able to regain their playing minutes and games 2 years after injury, while lower classed athletes did not reach the same amount within 3 years. Level of evidence Level III.
... However, soccer players with LBP may suffer from reduced performance, leading to early retirement 8) . Loose et al. 9) investigated the incidence and prevalence of injuries at five skill levels, with an overall injury incidence of 9.7 per 1000 h football exposure. Semi-professional players had a significantly high incidence of overall injury incidence (3.9 per 1000 h football), with the knees, ankles, and thighs most affected by trauma. ...
Studies have shown that soccer players have a high prevalence of low back pain (LBP). However, physical characteristics (sagittal spinal alignment and hip joint range of motion [ROM]) associated with LBP have not been clarified. This study seeks to clarify the relationship between physical characteristics and LBP in high school male soccer players. The participants were 90 high school male soccer players. The presence of LBP was evaluated using a questionnaire. We assigned the participants into two groups: the non-LBP group (n = 58) and the LBP group (n = 32). Passive ROM of hip and sagittal spinal alignment were measured. Thoracic kyphotic angle (TKA) was significantly higher in the LBP group than in the non-LBP group, and the ROM of hip joint extension in the nondominant leg was significantly lower in the LBP group than in the non-LBP group. On logistic regression analyses, TKA in the upright position (adjusted odds ratio [OR]: 1.087, 95% confidence interval [CI]: 1.019–1.159, p < 0.01) and hip extension ROM deficits in the nondominant leg (adjusted OR: 0.888, 95% CI: 0.789–0.999, p < 0.05) were related to LBP in high school male soccer players as determined. This study suggests that hyperkyphosis in the upright position and hip extension ROM deficits in the nondominant leg were related to LBP in high school male soccer players.
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Understanding the challenges football (soccer) players face during adolescence is fundamental to avoid disruptions in their development due to injury. This mini review will describe basic concepts of somatic growth and biological maturity, examine data from 53 prospective epidemiological studies on high-level youth football players and discuss how age, growth and maturity may affect the injury patterns observed. Based on the existing evidence, at least every third player sustains an injury during a football season. The thigh (median for studies of boys: 25%, median for girls: 21%), ankle (b: 18%, g: 30%), knee (b: 17%, g: 18%) and hip/groin (b: 14%, g: 10%) are the body parts injured most often, while muscle strains (b: 31%, g: 25%), sprains (b: 20%, g: 27%) and contusions (b: 17%, g: 16%) are the most common injury types. Injury trends are, however, not consistent throughout adolescence, and players' age, maturity status and position relative to peak height velocity (PHV) have shown to influence the number, type and location of injuries sustained. Despite a high volume of observational injury studies published on high-level youth players, girls (7 studies) and settings outside of Europe (included in 23% of studies) are underrepresented and should receive extra attention in the future. Based on the available epidemiological data, tailored injury reduction programmes can be considered in youth football, alongside application of general training principles such as progression, variation and individualization which may be especially important during vulnerable phases such as the adolescent growth spurt.
Conference Paper
Background Pre-elite athletes are at increased risk of injury/illness due to rapid increases in training load, insufficient rest and recovery, growth and a lack of support services compared to elite athletes. Objective Surveillance of incidence, site, nature and mechanisms of injury/illness at the 2018 & 2019 17/U & 19/U Australian Netball National Championships (ANNC) and reduce injuries at the 2019 ANNCs. Design Prospective observational cohort study. Setting 2018 & 2019 17/U & 19/U ANNC’s. Patients (or Participants) One hundred and ninety-two pre-elite athletes were observed each year. Interventions (or Assessment of Risk Factors) A foot blister prevention pack and advice regarding an injury prevention program were provided to each athlete 6 weeks prior to 2019 ANNC’s. Main Outcome Measurements Injuries were recorded prospectively by team physiotherapists using medical attention data collection methods at the 2018 & 2019 ANNCs. Results The most frequently recorded medical attention injury diagnoses in 2018 were ankle sprain (n=14, 13.6%), foot blisters (n=11, 10.7%), and lumbar pain (n=10, 9.7%). In 2019 there were 16 (16.8%) ankle sprains, followed by 12 (12.6%) episodes of lumbar pain and 8 (8.4%) foot blisters. In 2018 there were 22 (21%) sports incapacity injuries with ankle sprain (n=4, 18.2%), anterior cruciate ligament (ACL) rupture (n=3, 13.6%) and concussion (n=3, 13.6%) recorded most frequently. In 2019, there were 12 (12.6%) sports incapacity injuries with concussion (n=5, 5.3%) recorded most frequently followed by ACL rupture (n=4, 4.2%). The blister prevention intervention reduced the number of foot blisters at the 2019 ANNCs (IRR 0.73 0.58–0.91, p=0.002). Conclusions This is the first publication in recent times to articulate tournament injury rates for pre-elite netball athletes. Ankle sprains are the highest medical attention injury in pre-elite netball athletes. This has not changed over the past 30 years indicating current injury prevention interventions for ankle sprain are not effective. Blister prevention packs and advice reduced the number of foot blisters.
Background: Elite youth athletes participate in intense and structured training programmes to realise their performance potential, but their development may be interrupted by injuries. To reduce the impact of injuries we first need to know which injuries affect participation the most and what the risk factors are. Growth and maturation represent two potential non-modifiable intrinsic risk factors that are unique to adolescent athletes. The literature published on this topic is, however, considered of low quality and findings in earlier studies are inconsistent. The aim of this thesis was therefore to identify the most common and burdensome injuries in elite male youth athletes participating in football (soccer) and athletics (track and field) and to explore growth and maturation as risk factors. Methods: All studies were based on data from routine monitoring of athletes at Aspire Academy, a national elite sports academy in Doha, Qatar. Participants were males aged 11 to 18 years participating in the football or athletics programmes. The first study (Paper I) was a methodological study where we investigated the effect on injury incidence when a broad medical-attention definition was used and recorders/supervisors were invested in research projects relying on the data. This study was based on injury data for the U16 through U18 squads from 2012/13 through 2016/17 (211 players). Papers II and III were descriptive epidemiological studies in athletics and football, respectively. Time-loss injuries were collected prospectively over five seasons in athletics (2014/15 through 2018/19, 179 athletes) and four seasons in football (2016/17 through 2019/20, 301 players) by physiotherapists. The most common (injury incidence) and burdensome (injury burden) combinations of injury location and type were identified, and injury patterns were examined for event groups (athletics; non-specialised, endurance, sprints, jumps, throws) and age groups (football; U13 through U18). In Papers IV and V, subsamples of athletes (74 in athletics, 103 in football) from the epidemiological studies with complete growth (anthropometric measures, i.e. height, leg length and body mass) and maturity (skeletal age, using the Fels method) assessments were included. Growth rates, maturity status and maturity tempo were then examined as risk factors for specific injury types. Main results: The level of investment in the injury surveillance programme by the injury recorder (team physiotherapist) or supervisor had a large impact on the incidence of non-time-loss injuries and injuries with a minimal day loss (1-3 days), while time-loss injuries overall were unaffected (Paper I). In athletics (Paper II), the main concerns were bone and muscle injuries, with thigh muscle strains/ruptures, lumbar spine stress fractures and lower leg bone stress injuries as the most burdensome location-type combinations. Injury patterns were, however, specific to each event group. In football (Paper III), typical “football injuries” (knee sprains, thigh strains and ankle sprains) were the most burdensome, followed by lumbosacral bone stress injuries and physis injuries to the hip/groin. Older athletes sustained more injuries relative to exposure (hours); muscle injuries were increasingly common and physis injuries less common with age. In Paper IV, younger skeletal age and greater changes in height, leg length and skeletal age over a season were associated with a greater incidence of bone and growth plate injuries in athletics. No associations with injury risk were found for changes in body mass, trunk height or body mass index. In football (Paper V), growth rates over shorter periods were not related to injury risk when accounting for age (chronological age or skeletal age) and load (weekly exposure). Older skeletal age was associated with significantly greater overall, sudden onset, muscle and joint sprain injury risk. The associations could, however, not be considered practically relevant due to the uncertain estimates for the odds ratios. Conclusion: Based on our findings, time-loss incidence should be used when multiple medical staff recorders are involved in the data collection. Injuries patterns in elite male youth athletes are specific to the sport, event group and age group; tailoring injury reduction programmes may therefore be possible. A large proportion of lost training and competition days were attributed to bone injuries; these should be targeted to a larger degree in risk factor studies and in injury reduction programmes. Skeletal maturity appears to affect the risk of sustaining certain injury types in football and athletics, while growth rates were only related to injury risk in athletics. Practitioners and researchers may need to consider the full growth and maturity process, rather than analysing short isolated periods, to better understand the relationship between growth, maturation and injury risk.
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Introduction: Injuries are a common problem in football. To improve prevention strategies, the players' (p) and coaches' (c) views need to be disclosed as they have a strong impact on return to play decisions. The aim of this study is to reveal current opinions with regard to injury prevention and return to play strategies to introduce new strategies in elite football. Materials and methods: In a retrospective data analysis of elite salaried football players (n = 486) and team coaches (n = 88), a detailed investigation by means of a standardized questionnaire was carried out. In a preseason period of the 2015/16 season and as part of a large interventional research project in elite salaried German football, a request about players' and team coaches' knowledge and opinions was performed. Topics such as injury prevention, return to play after injuries, the importance of screening tests, general problems of injuries in football, or the decision-making in terms of prevention and return to play in elite football were investigated. Results: The study revealed a high interest in injury prevention and screening tests among players and coaches (p 82.5%; c 99.1%). The participants of the study reported warm-up exercises (p 76.4%; c 74.7%), regeneration training (p 54.1%; c 56.3%), and core stability (p 53.8; c 70.1%) as the most important prevention methods, but the additional investigation of the teams' current daily training routine showed that the transfer is incomplete. Coaches are more familiar with scientific published warm-up programs like FIFA 11 + than players (42.5 vs. 12.6; p < 0.001). Knee injuries (p 90.7%; c 93.1%) and ACL injuries in particular were reported as the most severe and common problem in elite football. Players and coaches expressed different attitudes concerning return to play decisions. While players want to decide themselves (81.4%), team coaches consult medical advice ahead of the decision of return to play after injuries (83.5%; p < 0.001). Decisions against the doctor's recommendation are often made by both groups (p 64.4% vs. c 87.1%; p < 0.001). Conclusion: The basic knowledge of prevention and injuries is sufficient in elite football, but the transfer from theoretical knowledge to practical routine is suboptimal. The study also shows possibilities to improve the prevention process and communication between players, coaches, doctors, and physiotherapists, while there is no consent between players and coaches regarding return to play decision.
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Introduction: This study analyzed the incidence and characteristics of injuries sustained by amateur youth football players in Portugal during season 2015 - 2016. Material and methods: This is an observational descriptive study. We analyzed Portuguese youth football players' injuries over six months of a season. A total of 529 players were divided according to their age in two groups (Under-17 and Under-19). Data on injuries were collected. Results: Throughout all 62 062.0 hours of exposure recorded, 248 injuries were reported in 173 different players. The average incidence of injury was 3.87 (95% CI = 2.81; 4.94) per 1000 hours of football exposure. There was a significantly higher average incidence of injury during matches - 14.22 (95% CI = 10.35; 18.09) per 1000 hours of exposure - when compared to the average incidence of injury during training - 2.06 (95% CI = 1.22; 2.90) per 1000 hours of exposure. This significance was also observed when the comparison was made within each age group. A traumatic mechanism was involved in 76.6% of all the injuries, while overuse was reported in 12.9%. The most common type was the injury that affected muscles and tendons (52.8%). The body location most commonly affected by injuries was the thigh (24.6%). Discussion: Even though is essential a better characterization of Portuguese athletes of younger age groups such as those discussed in this study, the results of the studied population are in agreement with the existing literature. However, this study provides more information that may be important to better target the Portuguese athletes' training for injury prevention. Conclusion: This study provides descriptive data on injuries developed in a subpopulation of Portuguese amateur youth football players that could represent a focus for future prevention.
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Objective: The objective of this study was to assess the efficacy of a newly developed warm-up programme ('11+ Kids') regarding its potential to reduce injuries in children's football. Methods: Children's football teams (under 9 years, under 11 years, and under 13 years age groups) from Switzerland, Germany, the Czech Republic and the Netherlands were invited. Clubs were randomised to an intervention group and a control group, and followed for one season. The intervention group replaced their usual warm-up by '11+ Kids', while the control group warmed up as usual. The primary outcome was the overall risk of football-related injuries. Secondary outcomes were the risks of severe and lower extremity injuries. We calculated hazard ratios using extended Cox models, and performed a compliance analysis. Results: In total, 292,749 h of football exposure of 3895 players were recorded. The mean age of players was 10.8 (standard deviation 1.4) years. During the study period, 374 (intervention group = 139; control group = 235) injuries occurred. The overall injury rate in the intervention group was reduced by 48% compared with the control group (hazard ratio 0.52; 95% confidence interval 0.32-0.86). Severe (74% reduction, hazard ratio 0.26; 95% confidence interval 0.10-0.64) and lower extremity injuries (55% reduction, hazard ratio 0.45; 95% confidence interval 0.24-0.84) were also reduced. Injury incidence decreased with increasing compliance. Conclusion: '11+ Kids' is efficacious in reducing injuries in children's football. We observed considerable effects for overall, severe and lower extremity injuries. The programme should be performed at least once per week to profit from an injury preventive effect. However, two sessions per week can be recommended to further increase the protective benefit. Trial registration: identifier: NCT02222025.
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Objectives Football has the highest sports participation (10.6%) in Ireland ahead of its Gaelic counterpart (3.9%). Research into injury incidence and patterns in Irish football is non-existent. The aim of this study was to conduct a prospective injury audit of League of Ireland (semiprofessional) footballers during the 2014 season (8 months, 28 games). Methods A total of 140 semiprofessional League of Ireland footballers were prospectively followed between March and November 2014. Data were collected in accordance with the international consensus on football injury epidemiology. Results The injury rate was 9.2/1000 hour exposure to football (95% CI 6.2 to 12.9, p<0.05). Players were at a higher risk of injury during a match compared with training (23.1 (95% CI 15.2 to 31.3) vs 4.8 (95% CI 2.2 to 7.7)/1000 hours, p<0.05). Injuries were most common during non-contact activity (54.6%), mainly running (30.9%), and occurred almost three times more often in the second half (56% vs 21%, p<05). Strains (50.1%) and sprains (20.3%) were the most common injury types, and the thigh region was injured most often (28.3%). Conclusions The prevalence of injury in League of Ireland football is similar to that of European professional football, although the incidence of injury is higher. The incidence of injury is in line with that of Dutch amateur football.
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Context: The incidence of injury for elite youth and professional adult soccer players is an important concern, but the risk factors for these groups are different. Objective: To summarize and compare the injury incidences and injury characteristics of male professional adult and elite youth soccer players. Data sources: We searched MEDLINE and Web of Science using the search terms elite, international, European, soccer, football, injury, injuries, epidemiology, incidence, prevalence, not female, not American football, and not rugby. We also used the search terms professional for studies on professional adult soccer players and high-level, soccer academy, youth, adolescent, and young for studies on elite youth soccer players. Study selection: Eligible studies were published in English, had a prospective cohort design, and had a minimum study period of 6 months. To ensure that injury data were assessed in relationship to the athlete's individual exposure, we included only studies that reported on injuries and documented exposure volume. Data extraction: Two independent reviewers applied the selection criteria and assessed the quality of the studies. Data synthesis: A total of 676 studies were retrieved from the literature search. Eighteen articles met the inclusion criteria: 6 for elite youth and 12 for professional adult soccer players. Conclusions: Injury rates were higher for matches than for training for both youth and adult players. Youth players had a higher incidence of training injuries than professionals. Efforts must be made to reduce the overall injury rate in matches. Therefore, preventive interventions, such as adequately enforcing rules and focusing on fair play, must be analyzed and developed to reduce match-related injury incidences. Reducing training injuries should be a particular focus for youth soccer players.
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Introduction: Scientific studies on injury characteristics are rather common in professional football but not in amateur football despite the thousands of amateur football tournaments taking place worldwide each year. The purpose of this study was to evaluate the preparation and injury patterns of players of two different football skill levels who participated in an international amateur football tournament. Methods: In a prospective cohort study, an international amateur football tournament of medical doctors in 2011 was analysed with regard to training and warm-up preparation, the level of football played before the tournament and injury data during the tournament by means of standardised injury definitions and data samples for football. Results: Amateur players of registered football clubs had higher training exposure before the tournament (p < 0.001) than recreational players and had more frequently performed warm-up programmes (p < 0.001). Recreational football players showed a significantly higher overall injury incidence (p < 0.002), particularly of overuse injuries (p < 0.001), during the tournament than amateur players. In almost 75 % of players in both groups, the body region most affected by injuries and complaints was the lower extremities. Orthopaedic and trauma surgeons had the lowest overall injury incidence and anaesthetists the highest (p = 0.049) during the tournament. Conclusion: For the first time, this study presents detailed information on the injury incidence and injury patterns of an amateur football tournament. Less-trained recreational players sustained significantly more injuries than better-trained amateur players, probably due to the lack of sufficient preparation before the tournament. Preventive strategies against overuse and traumatic injuries of recreational football players should start with regular training and warm-up programmes in preparation for a tournament.
The aim was to compare the epidemiology of injuries between elite male and female football players from the same club. Injuries and individual exposure time in a male team and a female team, both playing in the Spanish first division, were prospectively recorded by the club's medical staff for five seasons (2010-2015) following the FIFA consensus statement. Total, training and match exposure hours per player-season were 20% higher for men compared to women (P < 0.01). Total, training and match injury incidence were 30-40% higher in men (P ≤ 0.04) mainly due to a 4.82 [95% confidence interval (CI) 2.30-10.08] times higher incidence of contusions, as there were no differences in the incidence of muscle and joint/ligament injuries (P ≥ 0.44). The total number of absence days was 21% larger in women owing to a 5.36 (95% CI 1.11-25.79) times higher incidence of severe knee and ankle ligament injuries. Hamstring strains and pubalgia cases were 1.93 (95% CI 1.16-3.20) and 11.10 (95% CI 1.48-83.44) times more frequent in men, respectively; whereas quadriceps strains, anterior cruciate ligament ruptures and ankle syndesmosis injuries were 2.25 (95% CI 1.22-4.17), 4.59 (95% CI 0.93-22.76) and 5.36 (95% CI 1.11-25.79) times more common in women, respectively. In conclusion, prevention strategies should be tailored to the needs of male and female football players, with men more predisposed to hamstring strains and hip/groin injuries, and women to quadriceps strains and severe knee and ankle ligament injuries. This article is protected by copyright. All rights reserved.
PurposeThe incidence of groin pain in athletes is steadily increasing. Symptomatic pubic overload with groin pain and aseptic osteitis pubis represent well-known and frequently misdiagnosed overuse injuries in athletes. This study investigated the benefits of standardised non-surgical treatment for swift return-to-football. Methods In a prospective double-blinded controlled study, 143 amateur football players with groin pain as well as radiological signs and clinical symptoms of pubic overload were analysed for 1 year. Two randomised study groups participated in an intensive physical rehabilitation programme, either with or without shock wave therapy. The control group did not participate in any standardised rehabilitation programme but only stopped participating in sports activity. Follow-up examinations took place 1, 3 months and 1 year after the beginning of therapy. Endpoints were visual analogue scale (VAS), functional tests, the time of return-to-football, recurrent complaints and changes in the MR image. ResultsForty-four football players with groin pain and aseptic osteitis pubis were randomised into two study groups; 26 received shock wave therapy, 18 did not. Clinical examination showed pubic overload as a multi-located disease. Players receiving shock wave therapy showed earlier pain relief in the VAS (p < 0.001) and returned to football significantly earlier (p = 0.048) than players without this therapy. Forty-two of 44 players of both study groups returned to football within 4 months after the beginning of therapy and had no recurrent groin pain within 1 year after trauma. Fifty-one players of the control group returned to football after 240 days (p < 0.001), of whom 26 (51%) experienced recurrent groin pain. Follow-up MRI scans did not show any effect of shock wave therapy. Conclusion Non-surgical therapy is successful in treating pubic overload and osteitis pubis in athletes. Shock wave therapy as a local treatment significantly reduced pain, thus enabling return-to-football within 3 months after trauma. Early and correct diagnosis is essential for successful intensive physiotherapy. Level of evidence I.
Background The influence of fixture congestion on injury rates and team performance has only been scarcely investigated. Objective To study associations between match load, recovery days, injury rates and team match performances in professional football. Design Prospective cohort study. Setting European professional football. Participants 27 teams, all selected by the UEFA and all competing at the highest level of European football, playing 8 150 competitive matches during the 11-year study period were included. Assessment of risk factors Injury rates and team match performances were compared depending on the number of recovery days between matches using two different cut offs (≤3 vs. >3 days and ≤4 vs. ≥6 days). Match load, injury rates and team match performances were also studied over extended match sequences during the season, each sequence containing five consecutive matches over a mean of 27 days (range 7–104 days). Main outcome measurements Number of time loss injuries/1000 h of exposure and amount of matches won, lost or drawn. Results Team performance showed no association with match load except for Europa League matches that indicated more matches lost with ≤3 days compared with >3 days recovery (P=.048). Total injury rates and muscle injury rates, specifically hamstring and quadriceps injuries, were increased in league matches with ≤4 days compared with ≥6 days recovery preceding the match (rate ratio [RR] 1.09, 95% CI 1.00–1.18, and RR 1.32, 95% CI 1.15–1.51, respectively) while no differences were found when using the other cut off (≤3 vs. >3 days). High match load during a match sequence was associated with an increase in muscle injury rates (P=.012). Conclusions Fixture congestion was associated with increased muscle injury rates but had no, or very limited, influence on team match performances.
Epidemiological studies of football injuries are the basis for the implementation of prevention programs. So far, no epidemiological records are available from German professional men's football. This study aimed at analysing injuries in the first German football league by means of information from public media. 471 male players were analysed during the season 2004/05, provided they participated in at least one regular match. All available information on time- loss injuries (localisation, diagnosis, duration of absence) and on exposure time during regular matches was collected from print and online media ("Kicker Sportmagazin") regularly reporting injuries of first-league players. 392 players suffered from 1187 injuries. 441 injuries occurred during matches, corresponding to an incidence of 37.5 (95% CI = 34 - 41) injuries per 1000 playing hours. 76% of all injuries occurred at the lower extremities, with thigh (N=222), knee (N=197), and ankle (N=166) being the most frequent locations. N = 144 injuries (12%) led to absence of more than 28 days. 45% of these major injuries occurred at the knee. Injury frequency was increased at the end of match and rematch rounds. No significant correlation was observed between injury frequency and team success. Injury incidence in the German national league during the season 2004/05 was in the upper range of values reported by previous epidemiologic studies from other countries. Media-based injury statistics seemed almost complete, but an exact diagnosis was not possible in all incidents.