Soccer injuries: a review on incidence and prevention

OPHTHALMOLOGIC EVALUATION IN PROFESSIONAL MALE SOCCER PLAYERS IN BRAZIL

ABSTRACT Introduction: Soccer is the most popular sport in Brazil and worldwide, but there is insufficient data on the eye health of soccer players, and eye conditions may affect the well-being and performance of these athletes. Objective: To perform an ocular evaluation of a representative sample of professional soccer players from Brazil. Methods: This was a cross-sectional study conducted over four consecutive years (2009-2012) at a single professional soccer club in Brazil. The ophthalmology evaluation was performed by the same ophthalmologist in each sample. Prior to the ophthalmology evaluation, all participants filled out a questionnaire to provide the following demographic data: age, position, use of contact lenses or ophthalmic drugs, symptoms, previous ocular surgery, and date of the last ophthalmology evaluation. Visual acuity, intraocular pressure (IOP) and color vision were tested during the ophthalmologic examination, and ophthalmoscopy and biomicroscopy exams were performed. Results: One hundred and twenty bilateral ophthalmology evaluations were performed in 84 professional soccer players between 2009 and 2012. Pinguecula and pterygium were the most common conditions found in the athletes’ biomicroscopy exams, corresponding to 63% (38/60) and 17% (10/60) of abnormalities, respectively. In the contrast sensitivity evaluation, only one athlete was color blind. No significant associations were found between the position of the athlete and the results of the biomicroscopy and ophthalmoscopy exams. Conclusion: Despite the high prevalence of abnormalities found in the ophthalmology evaluation, most refractive abnormalities did not require correction, and the biomicroscopy abnormalities were mostly benign. Level III; Study of non-consecutive patients.

Relationship of Pre-season Training Load With In-Season Biochemical Markers, Injuries and Performance in Professional Soccer Players

INTRODUCTION

There is controversy in the literature in regards of the link between training load and injury rate. Thus, the aims of this non-interventional study were to evaluate relationships between pre-season training load with biochemical markers, injury incidence and performance during the first month of the competitive period in professional soccer players.

MATERIALS AND METHODS

Healthy professional soccer players were enrolled in this study over two pre-season periods. Data sets were available from 26 players during the first season (2014-2015) and 24 players during the second season (2015-2016) who completed two pre-season periods (6 weeks each). External training load was assessed from all athletes during training using Global Positioning System (GPS). Internal training load was monitored after each training session using rate of perceived exertion (RPE). Before and after each pre-season, blood samples were taken to determine plasma lactate dehydrogenase (LDH), creatine kinase (CK) and C-reactive protein (CRP). Injury incidence and overall performance (ranking of the team after the first five official games of the championship) were recorded for both seasons separately.

RESULTS

There was no statistically significant difference in mean RPE values of the two-preparation periods (2737 ± 452 and 2629 ± 786 AU, p = 0.492). The correlational analysis did not reveal significant associations between internal and external training load (RPE and GPS data) and biological markers. There was a significant positive correlation between RPE and LDH during the 2015/2016 season (r = 0.974, p = 0.001). In addition, a significant negative correlation was found between total distance >20 km/h and CRP during the 2015-2016 season (r = -0.863, p = 0.027). The injury rates for the two seasons were 1.76 and 1.06 per 1000 h exposure for the 2014-2015 and 2015-2016 seasons, respectively (p = 0.127).

CONCLUSION

Our study showed that pre-season training load is not associated with overall team performance. This association is most likely multifactorial and other factors (e.g., technical and tactical level of the team, opponents, environment) may play an important role for the collective team performance. Our findings may help coaches to better prepare their athletes during pre-season.

A study protocol for the development and internal validation of a multivariable prognostic model to determine lower extremity muscle injury risk in elite football (soccer) players, with further exploration of prognostic factors

BACKGROUND

Indirect muscle injuries (IMIs) are a considerable burden to elite football (soccer) teams, and prevention of these injuries offers many benefits. Preseason medical, musculoskeletal and performance screening (termed periodic health examination (PHE)) can be used to help determine players at risk of injuries such as IMIs, where identification of PHE-derived prognostic factors (PF) may inform IMI prevention strategies. Furthermore, using several PFs in combination within a multivariable prognostic model may allow individualised IMI risk estimation and specific targeting of prevention strategies, based upon an individual's PF profile. No such models have been developed in elite football and the current IMI prognostic factor evidence is limited. This study aims to (1) develop and internally validate a prognostic model for individualised IMI risk prediction within a season in elite footballers, using the extent of the prognostic evidence and clinical reasoning; and (2) explore potential PHE-derived PFs associated with IMI outcomes in elite footballers, using available PHE data from a professional team.

METHODS

This is a protocol for a retrospective cohort study. PHE and injury data were routinely collected over 5 seasons (1 July 2013 to 19 May 2018), from a population of elite male players aged 16-40 years old. Of 60 candidate PFs, 15 were excluded. Twelve variables (derived from 10 PFs) will be included in model development that were identified from a systematic review, missing data assessment, measurement reliability evaluation and clinical reasoning. A full multivariable logistic regression model will be fitted, to ensure adjustment before backward elimination. The performance and internal validation of the model will be assessed. The remaining 35 candidate PFs are eligible for further exploration, using univariable logistic regression to obtain unadjusted risk estimates. Exploratory PFs will also be incorporated into multivariable logistic regression models to determine risk estimates whilst adjusting for age, height and body weight.

DISCUSSION

This study will offer insights into clinical usefulness of a model to predict IMI risk in elite football and highlight the practicalities of model development in this setting. Further exploration may identify other relevant PFs for future confirmatory studies and model updating, or influence future injury prevention research.

The "FIFA 11+" injury prevention program improves body stability in child (10 year old) soccer players

The suitability of the FIFA 11+ prevention programme to improve selected performance outcomes in children aged < 14 years has not been established yet. This study aimed to investigate the effects of the FIFA 11+ programme on jump ability and stability in 10-year-old child soccer players. Sixteen young soccer players (aged 10 years) were randomly assigned to a conventional or a FIFA 11+ warm-up group. During a 5-week training period with 2 sessions per week the FIFA 11+ group warmed up with the 11+ programme, whereas the control group subjects performed their usual warm-up programme (e.g. running exercises with dribbling and/or passing techniques included). After the warm-up, both groups performed the same training exercises during each session. Before and after the training period, standing long jump performance and body stability (S3 Check, unstable uniaxial platform) were assessed. Significant improvements in the stability index were found in both groups (5.6±1.1 to 3.5±1.0 and 5.5±0.8 to 4.0±1.5 for the FIFA 11+ and the control group, respectively, p<0.001, partial η²=0.886 for the training effect of the analysis of variance) with likely (qualitative inference analysis) greater improvements in the FIFA 11+ group compared to the control group (p=0.078, partial η²=0.205 for the training x group interaction effect of the analysis of variance). Training had no effect on standing long jump performance (p>0.05). Data indicate that in 10-year-old soccer players the FIFA 11+ programme may have the potential to improve stability. Thus, the FIFA 11+ programme might contribute to injury prevention and possibly to better soccer performance as well. This might especially apply if the programme is performed over a longer period and/or with more weekly training sessions. Based on the present results the inclusion of such a programme within the training practice of the child soccer player can be recommended.

Epidemiology of injuries among Italian footballers: the role of the playing field

Background

Football has a higher injury rate compared with other team sports such as rugby, in terms of two main categories: intrinsic (individual) and extrinsic (environmental) factors. The playing field is an extrinsic risk factor which has been poorly investigated in the literature.

Purpose

The aim of our study was to define the incidence and risk factors of injuries in a cohort of footballers comparing the role of three different types of playing field (hard court, natural grass or synthetic grass).

Study design

This was a cross sectional prevalence study.

Methods

The population comprised footballers recruited by a convenience sample; the instrument used for the survey was an anonymous self-administered questionnaire.

Results

267 football players were enrolled (average age 23.4±4.8 years), of whom 33.7% (n=90/267) played on hard court, 33.0% (n=88/267) on natural grass and 33.3% (n=89/267) on synthetic grass. The overall incidence of injury was 40.1 (95% CI 34.1 to 46.8) ×1000 person-years of training, with higher values for ankle and knee injuries. Ankle injuries (aOR 0.4; P=0.021) were associated with playing on natural grass as a protective factor, while playing on natural grass seemed to be a risk factor for muscular injuries (aOR 2.3; P=0.026).

Conclusion

Our study showed a high lifetime prevalence of injury among footballers (57%), in particular among athletes who play and train on a hard court. We have studied a topic poorly investigated previously and provide the opportunity to understand interventions to increase the capacity of stakeholders in preventing injuries.

Meta-analysis of meta-analyses of anterior cruciate ligament injury reduction training programs

Several meta-analyses have been published on the effectiveness of anterior cruciate ligament (ACL) injury prevention training programs to reduce ACL injury risk, with various degrees of risk reduction reported. The purpose of this research was to perform a systematic review and meta-analysis of overlapping meta-analyses evaluating the effectiveness of ACL injury prevention training programs so as to summarize the amount of reduction in risk for all ACL and non-contact ACL injuries into a single source, and determine if there were sex differences in the relative efficacy of ACL injury prevention training programs. Five databases (Medline, PubMed, Embase, CINAHL, and Cochrane) were searched to identify meta-analyses that evaluated the effectiveness of ACL injury prevention training programs on ACL injury risk. ACL injury data were extracted and the results from each meta-analysis were combined using a summary meta-analysis based on odds ratios (OR). Eight meta-analyses met eligibility criteria. Six of the eight only included data for female athletes. Summary meta-analysis showed an overall 50% reduction (OR = 0.5 [0.41-0.59]; I²  = 15%) in the risk of all ACL injuries in all athletes and a 67% reduction (OR = 0.33 [0.27-0.41]; I²  = 15%) for non-contact ACL injuries in females. This paper combines all previous meta-analyses into a single source and shows conclusive evidence that ACL injury prevention programs reduce the risk of all ACL injuries by half in all athletes and non-contact ACL injuries by two-thirds in female athletes. There is insufficient data to make conclusions as to the effectiveness of ACL injury prevention programs in male athletes. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2696-2708, 2018.

Foot typology, body weight distribution, and postural stability of adolescent elite soccer players: A 3-year longitudinal study

Objective

The unique foot morphology and distinctive functions facilitate complex tasks and strategies such as standing, walking, and running. In those weight-bearing activities, postural stability (PS) plays an important role. Correlations among foot type, PS, and other musculoskeletal problems that increase sport injury risk are known. However, long-term associations among the foot type, the PS, and body weight (BW) distribution are lacking. Thus, the purpose of this study was to longitudinally identify changes in foot morphology, PS, and symmetry in BW distribution during adolescence among elite male soccer players.

Methods

Thirty-five Czech elite male soccer players (age, 15.49 ± 0.61 years; BW, 64.11 ± 6.16 kg; body height, 174.62 ± 5.71 cm) underwent foot type, PS, and BW distribution measurements during 3 consecutive years (T1, T2, T3). The Chippaux-Smirak index (CSI), BW distribution, and centre of pressure (COP) displacement (total traveled way [TTW]) of each player for the preferred (PL) and non-preferred leg (NL) were acquired. Repeated-measures analysis of variance (RM ANOVA), Bonferroni´s post hoc tests, and partial eta-squared (η_p²) coefficient were used for investigating the effect of time on selected variables and effect size evaluation.

Results

Statistically significant effect of time on CSI values (PL: F_2,68 = 5.08, p < 0.01, η_p² = 0.13 and NL: F_2,68 = 10.87, p < 0.01, η_p² = 0.24) and COP displacement values (PL: F_2,68 = 5.07, p <0.01, η_p² = 0.13; NL: F_2,68 = 3.53, p <0.05, η_p² = 0.09) for both legs over 3-years period was identified. Furthermore, the Bonferroni´s post hoc analysis revealed a significant improvement of PS values in the PL (TTW_T1 = 1617.11 ± 520.22 mm vs. TTW_T2 = 1405.29 ± 462.76, p < 0.05; and between TTW_T1 = 1617.11 ± 520.22 mm vs. TTW_T3 = 1370.46 ± 373.94, p < 0.05). Only BW distribution parameter showed no significant differences, although slightly improved over time.

Conclusions

We observed changes in foot typology, PS, and BW distribution in young elite male soccer players during 3 consecutive years. Results demonstrated that changes in PS and body weight distribution under the high-load sport conditions during adolescence may improve with aging, except for foot morphology. Therefore, foot morphology should be carefully monitored to minimize sport injury risk in professional young soccer players during adolescence. Further research is necessary to determine more clear associations between these parameters, soccer-related injuries, and sport performances.

Pre-season Fitness Level and Injury Rate in Professional Soccer - A Prospective Study

The aim of the present study was to assess prospectively the effect of pre-season fitness on injury rate during the competitive season among professional soccer players. Thirty-one players participated in the study during two consecutive competitive seasons (2015-16 and 2016-17; a squad of 22 players in each season). During the 6-week pre-season training period (8 training sessions and a friendly match every week, 14-18 training hours/week) there was a significant improvement in VO ₂ max, a significant increase in ideal and total sprint time and no change in vertical jump, flexibility and repeated sprint-test performance decrement. During the two consecutive seasons, 28 injuries were recorded. Ten injuries were classified as mild (missing 3-7 days of practice/match), 8 as moderate (missing 8-28 days) and 10 as severe (missing >28 days). The rate of match injuries was higher (9.4 per 1000 match hours) compared to practice injuries (4.7 per 1000 training hours). Most injuries were overuse injuries (72%) of the lower limbs (71%). Most of match injuries occurred during the last 15 min of each half. There were no differences in fitness characteristics in the beginning of pre-season training between injured and non-injured players. However, improvements in VO ₂ max during the pre-season training period were significantly lower among injured players (0.9±5.5%) compared to non-injured players (10.4±6.5%, p<0.05). Our results emphasize the importance of pre-season training in professional soccer players not only for improvement in fitness but also for injury prevention during the following competitive season.

Association between trunk pain and lower extremity pain among youth soccer players: a cross-sectional study

Background

Soccer is a high-intensity sport with a high injury rate. Among youth soccer players, lower extremity pain is a major problem that could be associated with trunk function. This study investigated the association between lower extremity pain and trunk pain among youth soccer players.

Methods

A cross-sectional study involving youth soccer players participating in the Miyagi Amateur Sports Association was conducted using a self-reported questionnaire. A multiple logistic regression analysis was used to examine the association between trunk pain and lower extremity pain. Covariates were sex, age, body mass index, height increase, number of days of training per week, practice time per day on weekdays or weekends, competition levels, frequency of participation in games, and previous injuries.

Results

The final study population comprised 1139 youth soccer players (age, 6-15 years; male, 94.2%). Lower extremity pain with concomitant trunk pain occurred in 61.8% (42/68). Trunk pain was significantly associated with lower extremity pain (adjusted odds ratio [OR], 6.82; 95% confidence interval [CI], 3.99-11.67). Back pain and hip pain were significantly associated with knee pain (adjusted OR [95% CI]: 7.63 [3.70-15.76] and 3.84 [1.89-7.83], respectively), ankle pain (adjusted OR [95% CI]: 9.03 [4.42-18.44] and 5.43 [2.77-10.62], respectively), and both knee and ankle pain (adjusted OR [95% CI]: 13.67 [6.01-31.09] and 5.98 [2.56-13.97], respectively).

Conclusions

Trunk pain was associated with lower extremity pain among youth soccer players. Clinicians and coaches should consider comorbidities while treating those players.

A review advocating caution with Major League Soccer expansion and investment in more rehabilitation professionals

BACKGROUND AND PURPOSE

Major League Soccer (MLS) has aggressively expanded from 10 teams to 23 teams. With the addition of more teams, the league will have to dictate a schedule that maximizes the league's popularity, while also maintaining the health of the players. A longer season and congested game schedule could increase the risk of injury for players. The purpose of this commentary is to make recommendations for the prevention of injuries among MLS players with respect to proposed league expansion.

DESCRIPTION OF TOPIC

MLS has lengthened the regular season with each expansion in teams. An increase in season length was seen in conjunction with the MLS expansion from 14 to 19 teams during the 2008 through 2013 seasons. Data from the inaugural MLS season found injury rates were higher in games compared to practices and more injuries occurred later in the season. With the expansion of MLS, anterior cruciate ligament tears appeared to have increased each year.

DISCUSSION

Current evidence suggests the implementation of a proper preseason in addition to the once-per-week game frequency would best promote player health and well-being. Players may benefit from in-season injury prevention training and weekly load monitoring.

Injuries Among Recreational Football Players: Results of a Prospective Cohort Study

OBJECTIVES

To establish the incidence and patterns of football injuries and associated consequences in daily life and labor loss, among public employees.

DESIGN

Prospective cohort study.

SETTING

Football tournament between public employees in Turkey.

PARTICIPANTS

A total of 1821 recreational players from 78 teams.

MAIN OUTCOME MEASURES

Injury rates (injuries per 1000 hours of football exposure) during tournament by age group, as well as prevalence, severity, and injury types were recorded. The data regarding the occurrence (eg, location, type, circumstances) and consequences (eg, absenteeism, medical treatment, labor loss) of injuries were collected.

RESULTS

Of the 1821 football players registered for participation, 57% (n = 1038) were included in the study with the returned questionnaire forms. In total, 257 matches were played with a total exposure time of 5654 hours. A total of 218 injuries were recorded in 192 players (10.5%), resulting in a mean of 0.85 time-loss injuries per match (38.6 per 1000 hours). Severe injuries constituted 42.6% of all injuries, and 28.9% of all injuries caused the participants to be absent at least 1 day for the next working day. The total labor loss was 1196 days for all injuries. The rate of missing subsequent working day was significantly less for muscle injuries (P < 0.05).

CONCLUSIONS

The risk of injury in recreational football players is relatively high causing significant labor loss. The results suggest that prevention programs should consider specific injury characteristics, as there is a greater incidence of muscle and anterior cruciate ligament injuries in this population.

Injuries in Spanish female soccer players

BACKGROUND

Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain.

METHODS

The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs (74.0%), mainly affecting knee (30.4%) and ankle joints (17.9%).

RESULTS

The proportion of injuries derived from contact with another player was higher during matches (33.7%) than during training (11.4%; p < 0.001). Noncontact injuries were classified as severe more frequently than were contact injuries (51.0% vs. 42.6%; p < 0.001). A higher incidence of injury was found in adult soccer players (≥18 years) vs. their counterparts younger than18 years (0.094 vs. 0.072 injuries per player per year, respectively; p < 0.001). There were no differences between age groups in any other injury variable (e.g., type, mechanism, location, or severity; p > 0.05).

CONCLUSION

Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics.

Awareness among Indian professional football players about injury prevention strategies: A national survey

OBJECTIVE

To determine the awareness and application of the injury prevention strategies by professional Indian football players through Standard Questionnaire Based Survey.

DESIGN

Descriptive Epidemiological Study.

SETTING

Professional football clubs in India.

PARTICIPANTS

Among 150 professional footballers playing in India, 109 football players participated..

PROCEDURE

The online questionnaire was made in the Google drive application. An online URL (www.tinyurl.com/futbolscptrc) was made in Google accounts by Google drive. 150 professional footballers playing in India were identified and invited to participate in this descriptive epidemiological online survey. All duly filled questionnaire responses were automatically reached in the Google drive inbox. Descriptive analysis was used for the data analysis.

RESULTS

Questionnaires were distributed to 150 professional players at nine Indian League clubs. 109 players responded, which represents a response rate of 73%. The player age and number of years as a professional footballers were 25 (4) years (range 18-38 years) and 6 (4) years (range 1-16 years) respectively. The players were from one Premier (9), two Division One (6 and 16), and two Division Two (9 and 15) teams.

CONCLUSIONS

Most of the professional Indian football players are aware about the injury prevention strategies. However, the application of these strategies is consistently followed by Premier division players.

Osteoarthritis of the hip and knee in former male professional soccer players

BACKGROUND

Professional soccer (PS) players are at great risk of osteoarthritis (OA) of the knee and hip.

SOURCES OF DATA

Following the PRISMA guidelines, the key words 'osteoarthritis' and 'soccer' or 'football' were matched with 'players' or 'former' or 'retired' and with 'hip' or 'knee' on December 24, 2017 in the following databases: PubMed, Cochrane, Google scholar, Embase and Ovid. Only comparative studies reporting the prevalence rate of OA of both hip and knee joint in former PS athletes (fPSa) and age and sex matched controls were considered.

AREAS OF AGREEMENT

In fPSa, the prevalence rate of OA of both hip and knee is significantly higher compared to age and sex matched controls.

AREAS OF CONTROVERSY

The pathological pathways responsible for the development of OA of the hip and knee in PS athletes (PSa) are still not clearly understood.

GROWING POINTS

The prevalence rate of clinical OA of the hip was 8.6% in fPSa and 5.6% in controls (odd ratio (OR) = 1.5; 95% CI: 1.06-2.31). The radiographic rate of OA was 21.2% in fPSa and 9.8% in controls (OR = 2.4; 95% CI: 1.66-3.69). A total of 14.6 and 53.7% of fPSa presented clinical and radiographic signs of OA of the knee, respectively, vs 12.9% (OR = 1.16; 95% CI: 0.86-1.55) and 31.9% (OR = 2.47; 95% CI: 2.03-3.00) of controls. Sonographic evidence of OA of the knee was found in 52% of fPSa and 33% of controls (OR = 2.2; 95% CI: 1.24-3.89).

AREAS TIMELY FOR DEVELOPING RESEARCH

Preventive training programmes should be developed to reduce the number of fPSa presenting early OA.

The FIFA 11+ injury prevention program for soccer players: a systematic review

Background

Soccer is one of the most widely played sports in the world. However, soccer players have an increased risk of lower limb injury. These injuries may be caused by both modifiable and non-modifiable factors, justifying the adoption of an injury prevention program such as the Fédération Internationale de Football Association (FIFA) 11+. The purpose of this study was to evaluate the efficacy of the FIFA 11+ injury prevention program for soccer players.

Methodology

This meta-analysis was based on the PRISMA 2015 protocol. A search using the keywords “FIFA,” “injury prevention,” and “football” found 183 articles in the PubMed, MEDLINE, LILACS, SciELO, and ScienceDirect databases. Of these, 6 studies were selected, all of which were randomized clinical trials.

Results

The sample consisted of 6,344 players, comprising 3,307 (52%) in the intervention group and 3,037 (48%) in the control group. The FIFA 11+ program reduced injuries in soccer players by 30%, with an estimated relative risk of 0.70 (95% confidence interval, 0.52–0.93, p = 0.01). In the intervention group, 779 (24%) players had injuries, while in the control group, 1,219 (40%) players had injuries. However, this pattern was not homogeneous throughout the studies because of clinical and methodological differences in the samples. This study showed no publication bias.

Conclusion

The FIFA 11+ warm-up program reduced the risk of injury in soccer players by 30%.

Multifactorial examination of sex-differences in head injuries and concussions among collegiate soccer players: NCAA ISS, 2004-2009

Background

While head injuries and concussions are major concerns among soccer players, the multifactorial nature of head injury observations in this group remains relatively undefined. We aim to extend previous analyses and examine sex-differences in the incidence of head injuries, odds of head injuries within an injured sample, and severity of head injuries, among collegiate soccer players between 2004 and 2009.

Methods

Data collected within the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) between the years of 2004 and 2009, were analyzed in this study. Unadjusted rate ratios (RR), compared incidence rates between categories of sex, injury mechanism, setting and competition level. We also examined sex-differences in head injury incidence rates, across categories of the other covariates. Multivariable logistic regression and negative binomial regression modeling tested the relation between sex and head injury corollaries, while controlling for contact, setting, and competition level.

Results

Between 2004 and 2009, head injuries accounted for approximately 11% of all soccer-related injuries reported within the NCAA-ISS. The rate of head injuries among women was higher than among men (RR = 1.23, 95% CI = [1.08, 1.41]). The rate of head injuries due to player-to-player contact was comparable between women and men (RR = 0.95, 95% CI = [0.81, 1.11]). Whereas, the rate of injury due to contact with apparatus (ball/goal) was nearly 2.5 times higher (RR = 2.46, 95% CI = [1.76, 3.44]) and the rate due to contact with a playing surface was over two times higher (RR = 2.29, 95% CI = [1.34, 3.91]) in women than in men. In our multifactorial models, we also observed that the association between sex and head injury corollaries varied by injury mechanism.

Conclusions

Sex-differences in the incidence, odds (given an injury), and severity (concussion diagnosis, time-loss) of head injuries varied by injury mechanism (player-to-player contact vs. all other mechanisms) in this sample.

PROSPECTIVE EVALUATION OF INJURIES OCURRED DURING A PROFESSIONAL SOCCER CHAMPIONSHIP IN 2016 IN SÃO PAULO, BRAZIL

OBJECTIVE

To identify the incidence of injuries, their main characteristics, and the way they were managed throughout 2016 in two major series of a professional soccer championship in São Paulo, Brazil.

METHODS

This prospective study used an electronic questionnaire previously developed by the Medical Committee of the Paulista Soccer Federation which was sent to the team doctors after each match.

RESULTS

Two hundred and fifty-nine injuries occurred during 361 matches, and the incidence of injury per 1000 hours of game play was 21.32. Strikers were the most affected by injury; the most frequent diagnosis was muscle injury and the legs were predominantly affected. Most of the injuries occurred in the last 15 minutes of the first half and only 7.7% required surgical treatment.

CONCLUSIONS

Muscle injuries were the most frequent, with most occurring in forwards and in the legs. Approximately half of the injuries occurred after contact and the vast majority was treated without surgery. MRI was the most requested exam and most injuries were classified as moderate (8 to 28 lost play days). Level of Evidence III, Study of Non Consecutive Patients; Without Consistently Applied Reference "Gold" Standard.

Balance Training Programs in Athletes - a Systematic Review

It has become almost routine practice to incorporate balance exercises into training programs for athletes from different sports. However, the type of training that is most efficient remains unclear, as well as the frequency, intensity and duration of the exercise that would be most beneficial have not yet been determined. The following review is based on papers that were found through computerized searches of PubMed and SportDiscus from 2000 to 2016. Articles related to balance training, testing, and injury prevention in young healthy athletes were considered. Based on a Boolean search strategy the independent researchers performed a literature review. A total of 2395 articles were evaluated, yet only 50 studies met the inclusion criteria. In most of the reviewed articles, balance training has proven to be an effective tool for the improvement of postural control. It is difficult to establish one model of training that would be appropriate for each sport discipline, including its characteristics and demands. The main aim of this review was to identify a training protocol based on most commonly used interventions that led to improvements in balance. Our choice was specifically established on the assessment of the effects of balance training on postural control and injury prevention as well as balance training methods. The analyses including papers in which training protocols demonstrated positive effects on balance performance suggest that an efficient training protocol should last for 8 weeks, with a frequency of two training sessions per week, and a single training session of 45 min. This standard was established based on 36 reviewed studies.

Orthopaedics injuries in male professional football players in Brazil: a prospective comparison between two divisions

BACKGROUND

Football is a high-speed contact sport and the risk of injury is high. The objective of this study was to compare the two main divisions (A1 and A2) of the São Paulo Football Championship and to perform a correlation analysis of the variables studied.

METHODS

A prospective study was conducted using an electronic questionnaire previously developed by the Medical Committee of the São Paulo Football Federation. The questionnaire was sent to the doctors of the teams playing in the A1 and A2 divisions of the São Paulo Football Championship after each round. Setting: 2016 São Paulo Football Championship.

RESULTS

The comparison of divisions A1 and A2 showed few significant differences among the various variables analysed in this study. The only significant differences were for right-side involvement in division A1 (p=0.044) and morning matches in division A2 (p<0.001). The correlation analysis of the variables studied showed expected associations, including sprains with a higher rate of need for surgery, ultrasound with muscle strains and moderate severity (8-28 days lost) with muscle strains.

CONCLUSION

Despite the differences between the two divisions regarding budgets and team characteristics, there was a little difference in the variables analysed and there were associations such as sprains with a higher rate of need for surgery, ultrasound with muscle strains and moderate severity (8-28 days lost) with muscle strains.

LEVEL OF EVIDENCE

II b, individual cohort study.

Groin Problems in Male Soccer Players Are More Common Than Previously Reported

BACKGROUND

The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods.

PURPOSE

To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new surveillance method developed to capture acute and overuse problems.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams across different levels of play and from both sexes were included, and they responded to the weekly questionnaire. We calculated the average weekly prevalence of all groin problems and substantial groin problems.

RESULTS

Of the 240 players, 112 male players (59%) and 20 female players (45%) reported at least 1 episode of groin problems. The average weekly prevalence of any groin problem and substantial groin problem for all male players was 29% (range, 23%-32% across different levels) and 10% (7%-13%), respectively. Elite male players had an increased risk of experiencing groin problems (odds ratio: 3.1, 95% CI: 1.5-6.4, P = .03) compared with elite female players. There was no difference in the risk of experiencing groin problems among elite, subelite, and amateur male players. For substantial problems, there was no difference between elite male and elite female players or among levels of play for senior male soccer players.

CONCLUSION

We found a high prevalence of groin problems among male soccer players during a period with match congestion. Time-loss definition as used in previous injury surveillance studies captured only one-third of the male groin problems registered with the new method. Elite male players had 3 times' higher risk of reporting groin problems as compared with elite female players, while playing level did not influence the risk of reporting a groin problem among males.

Osteoarthritis in Football

Football is currently the most popular sporting activity in the world. Multiple reports have shown that a high incidence of osteoarthritis is found in football players. Evidence clearly shows that traumatic injury significantly predisposes players for such pathophysiology. Injuries are frequent in amateur as well as professional football players, with knee and ankle accounting for the most severe injuries. Many professional athletes lose playing time due to injuries and many are forced into early retirement. Posttraumatic osteoarthritis is a common finding among ex-football players with numbers well above the normal population. Today's surgical techniques are advanced and capable of restoring the joint to a certain extent. However, a restitution ad integrum is reached only in very rare cases. Professional football players that return to play after serious injuries perform their extremely strenuous activity on morphologically compromised joints. Incomplete rehabilitation and pressure to return to play after an injurious event clearly put the athlete at an even higher risk for joint degeneration. Prevention strategies, improved surgical management, strict rehabilitation, as well as future aspects such as early suppression of inflammation, personalized medicine, and predictive genomics DNA profiling are needed to reduce incidence and improve the health perspectives of football players.

Osteoarthritis and joint replacements of the lower limb and spine in ex-professional soccer players: A systematic review

After a professional career as a soccer player, the risk of developing osteoarthritis (OA) in different joints of the spine and lower limb might be increased. The extent of this problem to date is not clear. Therefore, the aim of this systematic review is to summarize the prevalence of OA and joint replacement of the lower limb and spine in former professional soccer players. Relevant databases were searched with different combinations of key words: for example, OA, hip, knee, ankle, foot, joint replacement, soccer. Studies were included if they were original research, included a sample of former professional male soccer players, and had OA in the lower limb and/or spine; OA was diagnosed either through questionnaires or X-rays; and the article is in English, Dutch, or German. Sixteen studies with 1576 former players and 2153 control subjects were included in the review. Studies agreed that the prevalence of hip OA and hip replacements is significantly higher in former players compared to the control group. For the ankle and spine, there is only limited information, and for the prevalence of knee OA and knee replacement, the results are contradictory. The quality of the included studies was moderate. Future studies should have a prospective design to control for confounding factors, to identify possible risk factors and consequences for the individuals, and to be able to develop a prevention program.

Differences in the Dominant and Non-Dominant Knee Valgus Angle in Junior Elite and Amateur Soccer Players after Unilateral Landing

More than 70% of all knee injuries in soccer occur in non-contact situations. It is known that increased lower limb dynamic knee valgus is associated with such situations. Little has been found out about differences in knee kinematics of the dominant (kicking) and non-dominant (supporting) leg during a single leg landing. A total of 114 male adolescent soccer players (age 14.6 ± 1.1 years) from elite (N = 66) and amateur soccer clubs (N = 48) performed a single leg drop landing down from a box. For each leg, the two-dimensional dynamic knee valgus angle (DKVA) was calculated. Paired t-tests were used to statistically determine significant differences between dominant and non-dominant leg DKVA, and t-tests were calculated between the two performance groups. Statistically significant differences (p < 0.05) were identified for the DKVA between the dominant and non-dominant leg for both amateur and elite players, showing a greater DKVA for the dominant leg. Group differences for the DKVA between amateur and elite players were not found, neither for the dominant, nor for the non-dominant leg. It can be concluded that the non-dominant leg showed more stable dynamics than the dominant leg during unilateral landing regardless of the player’s performance level. This could be due to adaptions to sport-specific requirements. Therefore, it is recommended that programs to prevent knee injuries among soccer players consider the dynamics of each leg individually.

Time Trends in Incidence and Severity of Injury Among Collegiate Soccer Players in the United States: NCAA Injury Surveillance System, 1990-1996 and 2004-2009

BACKGROUND

A number of sociocultural and environmental changes have occurred over the past several decades that may affect the risk of injury among young athletes playing soccer.

PURPOSE

To identify trends in injury incidence and severity between 2 time periods (1990-1996 and 2004-2009) in both male and female National Collegiate Athletic Association (NCAA) soccer players in the United States.

DESIGN

Descriptive epidemiology study.

METHODS

Data were analyzed from the NCAA Injury Surveillance System. The rate ratio (RR), along with the 95% Wald CI, compared incidence density in 2004-2009 relative to that in 1990-1996.

RESULTS

Overall sex-pooled injury rates were significantly lower in the 2004-2009 cohort compared with the 1990-1996 cohort (RR = 0.88; 95% CI = 0.86-0.91), and this was true for almost every category of injury studied. We observed only 1 significant sex difference between the time periods with regard to noncontact injuries, as men experienced a significant increase in rate of noncontact injuries between 1990-1996 and 2004-2009 (RR = 1.09; 95% CI = 1.02-1.17), whereas women experienced a significant decrease (RR = 0.70; 95% CI = 0.67-0.75).

CONCLUSION

These surveillance data show decreasing trends in collegiate soccer injuries. Whether these decreases are attributable to greater resources being allocated toward athlete health, injury management, or the safety of the playing environment cannot be determined. Given the prominence of soccer play in the United States, public health efforts should promote the use of this surveillance system to better inform and evaluate injury prevention practices and policies directed toward player safety.

Effects of the FIFA 11 training program on injury prevention and performance in football players: a systematic review and meta-analysis

Objective:

To investigate the effects of FIFA 11 training on injury prevention and performance in football players.

Design and methods:

Systematic review and meta-analysis. We conducted a systematic search using four databases (CINAHL, Cochrane Library, EMBASE, and PubMed) to find controlled trials evaluating the effects of FIFA 11 on injury prevention and performance among football players. Weighted mean differences, standard mean differences, risk ratios, and 95% confidence intervals were calculated, and heterogeneity was assessed using the I2 test.

Results:

We analyzed 11 trials, including 4700 participants. FIFA 11 resulted in a significant reduction in injury risk (risk ratio = 0.69; 95% confidence interval, 0.49–0.98; P = 0.02) and improvements in dynamic balance (weighted mean difference = 2.68; 95% confidence interval, 0.44–4.92; P = 0.02) and agility (standard mean difference = −0.36; 95% confidence interval, 0.70–0.02; P = 0.04). The meta-analysis indicated a non-significant improvement in jump height (standard mean difference = 0.25; 95% confidence interval, 0.08–0.59; P = 0.14) and running sprint (standard mean difference = −0.24; 95% confidence interval, 0.58–0.10; P = 0.17) in the FIFA 11 group.

Conclusions:

FIFA 11 can be considered as a tool to reduce the risk of injury. It may improve dynamic balance and agility and can be considered for inclusion in the training of football players.

Injury incidence in a Premier League youth soccer academy using the consensus statement: a prospective cohort study

Background

There is an established risk of injury to young athletes exposed to high training loads. Identifying and monitoring injury risk is essential to aid prevention. The aim of this study was to use the consensus statement to determine the incidence and pattern of injury in 1 English Premier League soccer academy during 1 season.

Methods

A prospective cohort study included 181 elite academy soccer players during the 2012–2013 season. Players were divided into 5 age groups between 9 and 18 years. The number, type and incidence of injuries were recorded during matches and training. Incidence was calculated per 1000 hours of exposure.

Results

127 injuries occurred during 29 346 hours of soccer exposure. 72% of injuries were non-contact related. Under (U)18 players sustained the highest number of match injuries. U12–14 players sustained the highest number of training injuries and injuries overall. U16 players sustained the highest number of severe injuries, and U18 players sustained the highest number of moderate injuries. U18 players sustained the highest number of injuries/1000 hours of training and overall. U15 players sustained the highest number of injuries/1000 hours of matches, the highest number of recurrent injuries and the highest incidence of recurrence. The most common injuries were muscle injuries in U15 and U18 players. The most common injury location was the anterior thigh, with the majority of these occurring in training.

Conclusions

Using the consensus statement, this study used a repeatable method to identify the injury profile of elite academy-level soccer players.

Postural Stability During Single-Leg Stance: A Preliminary Evaluation of Noncontact Lower Extremity Injury Risk

Study Design Controlled laboratory study with a prospective cohort design. Background Postural stability deficits during single-leg stance have been reported in persons with anterior cruciate ligament (ACL) injury, ACL reconstruction, and chronic ankle instability. It remains unclear whether impaired postural stability is a consequence or cause of these injuries. Objectives To prospectively investigate whether postural stability deficits during single-leg stance predict noncontact lower extremity injuries. Methods Fifty injury-free female athletes performed a transition task from double-leg stance to single-leg stance with eyes closed. Center-of-pressure displacement, the main outcome variable, was measured during the first 3 seconds after the time to a new stability point was reached during single-leg stance. Noncontact lower extremity injuries were recorded at a 1-year follow-up. Results Six participants sustained a noncontact ACL injury or ankle sprain. Center-of-pressure displacement during the first 3 seconds after the time to a new stability point was significantly increased in the injured (P = .030) and noninjured legs (P = .009) of the injured group compared to the respective matched legs of the noninjured group. The area under the receiver operating characteristic curve (AUC) analysis revealed significant discriminative accuracy between groups for the center-of-pressure displacement during the first 3 seconds after the time to a new stability point of the injured (AUC = 0.814, P = .015) and noninjured legs (AUC = 0.897, P = .004) of the injured group compared to the matched legs of the noninjured group. Conclusion This preliminary study suggests that postural stability measurements during the single-leg stance phase of the double- to single-leg stance transition task may be a useful predictor of increased risk of noncontact lower extremity injury. Further research is indicated. Level of Evidence Prognosis, level 4. J Orthop Sports PhysTher 2016;46(8):650-657. Epub 3 Jul 2016. doi:10.2519/jospt.2016.6278.

Injuries during football tournaments in 45,000 children and adolescents

Four percent of the world's population, or 265 million people, play football, and many players are injured every year. The present study investigated more than 1800 injuries in over 45,000 youth players participating in three consecutive international football tournaments in Denmark in 2012-2014. The aim was to investigate the injury types and locations in children and adolescent football players and the differences between genders and age groups (11-15 and 16-19 years of age). An overall injury rate of 15.3 per 1000 player hours was found. The most common injury location was lower extremities (66.7%), and the most common injury type was contusion (24.4%). Girls had a relative risk of injury of 1.5 compared with boys, p < .001, and they had a higher proportion of injuries to knee and lower leg, 23.8%, than boys, 19.0%, p < .01. Boys had a higher proportion of fracture, 6.8%, as opposed to 3.3% among girls, p < .001. In conclusion, we found the youngest girls to have a higher incidence of almost all injury categories than any other group. In general, the incidence of injury decreased with age. The study provides a detailed insight into the injuries that may be expected at a large youth football tournament. These findings are of great value for organizations and healthcare professionals planning similar events and for planning injury prevention strategies, which would be of special interest in the youngest female players in general.

Power and endurance in Hong Kong professional football players

Background

The purpose of this study was to investigate the power and endurance characteristics of Hong Kong professional football players. Training recommendations can be deduced based on the comparison between Hong Kong and international football players.

Methods

Eighty-eight Hong Kong professional football players (height, 177.2 ± 6.4 cm; weight, 70.6 ± 7.6 kg; age, 25.6 ± 5.0 years) in the first division league participated in a battery of tests, which included: (1) height, (2) weight, (3) countermovement jump, (4) 30-m sprinting, and (5) Yo-Yo Intermittent Recovery Test Level 2.

Results

Compared with the test results of the first division players in other countries as reported in the literature (Norway, France, and Scandinavian countries), Hong Kong players were shorter in height (0.1–2.1%), lighter in weight (5.5–8.3%), fair in vertical jump height (−4.8–17%), slower in acceleration (4.2–5.1%) and maximum speed (3–14.2%), and had poorer aerobic and anaerobic endurance (22.9%).

Conclusion

The present study suggests that Hong Kong football players (or players with similar physique and ability) need to improve their power and endurance.

MRI of the knees in asymptomatic adolescent soccer players: A case-control study

PURPOSE

To determine the range of asymptomatic abnormal findings in adolescent soccer players at 3.0T MRI of the knee.

MATERIALS AND METHODS

In all, 87 knees of asymptomatic 14-17-year-old male adolescents were evaluated at 3T, using a standardized examination protocol comprising four sequences: two fat-suppressed T₂ -weighted fast spin-echo sequences (T₂ FSE), in the sagittal (repetition time / echo time [TR/TE], 5.300/71, echo train length [ETL] 17) and coronal planes (TR/TE, 4234/70, ETL 17), one fat-suppressed proton density (PD) sequence in the axial plane (TR/TE, 2.467/40, ETL 9), and one T₁ -weighted spin-echo (T₁ SE) sequence in the sagittal plane (TR/TE, 684/12.5). Soccer players (46 knees) were paired with controls (41 knees) by age and weight. Bone marrow, articular cartilage, meniscus, tendons, ligaments, fat pad abnormalities, and joint fluid were assessed.

RESULTS

One or more abnormalities were detected in 31 knees (67.4%) in the soccer player group, compared to 20 knees (48.8%) in the control group. The prevalence of bone marrow edema was higher in the soccer group (19 knees, 41.3%) than in the control group (3 knees, 7.3%), P = 0.001. Other abnormalities found in this sample (joint effusion, cartilage lesions, tendinopathy, ganglion cysts, and infrapatellar fat pat edema) were not significantly different between the two study groups.

CONCLUSION

Asymptomatic adolescents had a high prevalence of abnormal findings on knee imaging, especially bone marrow edema. This prevalence was higher among soccer players.

LEVEL OF EVIDENCE

4 J. Magn. Reson. Imaging 2017;45:59-65.

Foot and Ankle Injuries in Professional Soccer Players: Diagnosis, Treatment, and Expectations

Soccer is one of the most popular sports in the world. It has undergone many changes in recent years, mainly because of increased physical demands, and this has led to an increased injury risk. Direct contact accounts for half of all injuries in both indoor and outdoor soccer and ankle sprains are the most common foot and ankle injury. There is a spectrum of foot and ankle injuries and their treatment should be individualized in these high-demand patients. An injury prevention program is also important and should the players, the trainer, responsible physician, and physical therapists.

Analysis of Injury Incidences in Male Professional Adult and Elite Youth Soccer Players: A Systematic Review

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.

Risk Factors for Noncontact Ankle Injuries in Amateur Male Soccer Players: A Prospective Cohort Study

OBJECTIVE

To determine whether nonmodifiable and modifiable risk factors [ankle dorsiflexion range of motion (ROM), lower limb power output, and balance], as identified in preseason screening, predict the risk of sustaining a noncontact ankle injury in amateur male soccer players during the training and competitive season.

DESIGN

Prospective cohort study.

SETTING

Amateur soccer competition (club and area representative teams).

PARTICIPANTS

Amateur soccer players (n = 210) aged ≥15 years.

ASSESSMENT OF RISK FACTORS (INDEPENDENT VARIABLES)

Height, weight, ankle dorsiflexion ROM, power (vertical jump) and balance (time of double-leg balanced stance on an electronic wobble board, maximum 20 seconds) measured in preseason screening.

MAIN OUTCOME MEASURES (DEPENDENT VARIABLE)

Incidence of noncontact ankle injury and exposure to both training and games, monitored during the competitive season following baseline measurement. Noncontact ankle injury was defined as any ankle injury not caused by a collision (with another player or object) resulting in a participant missing at least 1 game or training session.

RESULTS

Fourteen of the 210 participants (6.7%) sustained a noncontact ankle injury yielding an injury rate of 0.484 injuries per 1000 player hours. Lower limb power output scores <30 W/kg [odds ratio (OR), 9.20, 95% confidence interval (CI), 1.13-75.09, P = 0.038] and poorer balance scores (OR, 0.43, 95% CI, 0.21-0.89, P = 0.024) were associated with higher odds of injury.

CONCLUSIONS

Poorer lower limb power output and balance are risk factors for noncontact ankle injury among amateur soccer players. These deficits can potentially be identified by screening, providing opportunities to investigate prevention strategies.

Preseason Strategies of Italian First League Soccer Clubs in Relation to their Championship Ranking: A Five-Year Analysis

This study is focused on the strategies adopted by Italian ‘Serie A’ soccer clubs during the non-competitive period. Thus, duration (i.e., number of days) of the specific non-competitive periods (i.e., off- plus pre-season, off-season, pre-season, summer camp), the number of games (i.e., friendly, official and polled games) and days between games (i.e., ≤ 3, 4-5, or ≥ 6 days between two consecutive games) of the entire non-competitive period were recorded and compared by clubs participating in the European Championships (EU), only ‘Serie A’ (A) and promoted from ‘Serie B’ (B) during five and single seasons (i.e., 2009/10-2013/14). Due to the short B off-season duration (2009/10-2013/14, 2010/11, 2011/12, 2012/13, 2013/14, p≤.001), effects between clubs emerged also for the off- plus preseason (2009/10-2013/14, EU vs A, p≤.01, EU vs B, p≤.01, A vs B, p≤.001; 2011/12, 2012/13, 2013/14, p≤.001). Nevertheless, no difference between clubs resulted for the pre-season. Reduced duration of summer camps was reported by the EU (i.e., 2009/10-2013/14, 2009/10, 2013/14, p≤.001). A higher number of official games were played by EU than A (i.e., 2009/10-2013/14, p≤.001; 2010/11, p≤.01). No effect emerged for the days between games. Therefore, despite the longer ‘Serie B’ schedule and EU preliminary UEFA games that determined the off-season restriction, clubs demonstrated the tendency to guarantee satisfactory pre-season duration.

Injury prediction in veteran football players using the Functional Movement Screen™

The Functional Movement Screen™ (FMS™) is aimed at assessing fundamental movements and is often used to identify players' injury risk. The purpose of this study was to determine whether the FMS™ can be used to predict injuries in veteran footballers (aged > 32 years). Eighteen veteran football teams (n = 238) were recruited and prospectively followed for 9 months. The players (44 ± 7 years; 178 ± 7 cm, 84 ± 11 kg) performed the FMS™ at the start of the study period. Players' exposure hours and injuries were recorded. The difference of FMS™ overall score between injured and uninjured players was not significant (11.7 ± 2.9 vs 12.2 ± 2.8 points; Mann-Whitney U-test P = 0.17). Players scoring <10 (score < 1 standard deviation [SD]) below the mean) had a significantly higher injury incidence (z-statistics P < 0.05) compared to an intermediate reference group (mean ± 1 SD; scores of 10-14). No lower injury incidence for players with scores of >14 (score > 1 SD above the mean) was found. Further analyses of potential risk factors suggest higher age, lower body mass and a longer football career to be risk factors for injuries. The findings of this study suggest that the suitability of the FMS™ for injury prediction in veteran footballers is limited.

The acute effect of match play on hamstring strength and lower limb flexibility in elite youth football players

The aim of this study was to investigate the effect of competitive football match play on hamstring strength and lower limb flexibility. Fifteen male international youth football players were included. Hamstring strength and associated pain ratings, ankle dorsiflexion, hip extension, knee extension and flexion range of motion were evaluated immediately post-match and at intervals of 24, 48, and 72 h post-match. Strength significantly reduced post-match (P < 0.01), mean difference -0.43 (CI₉₅ : -0.56, -0.30) and 24 h post (P < 0.05) mean difference -0.12 Nm/kg (CI₉₅ : -0.20, -0.04). The associated pain scores significantly increased at the post-match (P < 0.01, ES = 0.61) and 24 h (P < 0.01, ES = 0.55) time intervals. At the 48 and 72 h post-match tests no significant difference was found for strength or pain ratings. No significant differences were detected for any of the range of motion measures. Competitive football match play has a significant acute and transient effect on isometric hamstring strength and associated pain levels during resisted knee flexion in male international youth players. Range of motion measures appear to remain relatively unaffected by match play. Isometric hamstring strength testing and associated pain levels might be considered for inclusion in-season to monitor player's post-match hamstring recovery characteristics.

Efficacy of the FIFA 11+ Injury Prevention Program in the Collegiate Male Soccer Player

BACKGROUND

The Fédération Internationale de Football Association (FIFA) 11+ program has been shown to be an effective injury prevention program in the female soccer cohort, but there is a paucity of research to demonstrate its efficacy in the male population.

HYPOTHESIS

To examine the efficacy of the FIFA 11+ program in men's collegiate United States National Collegiate Athletic Association (NCAA) Division I and Division II soccer.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Before the commencement of the fall 2012 season, every NCAA Division I and Division II men's collegiate soccer team (N = 396) was solicited to participate in this research study. Human ethics review board approval was obtained through Quorum Review IRB. Sixty-five teams were randomized: 34 to the control group (CG; 850 players) and 31 to the intervention group (IG; 675 players). Four teams in the IG did not complete the study, reducing the number for analysis to 61. The FIFA 11+ injury prevention program served as the intervention and was utilized weekly. Athlete-exposures (AEs), compliance, and injury data were recorded using a secure Internet-based system.

RESULTS

In the CG, 665 injuries (mean ± SD, 19.56 ± 11.01) were reported for 34 teams, which corresponded to an incidence rate (IR) of 15.04 injuries per 1000 AEs. In the IG, 285 injuries (mean ± SD, 10.56 ± 3.64) were reported for 27 teams, which corresponded to an IR of 8.09 injuries per 1000 AEs. Total days missed because of injury were significantly higher for the CG (mean ± SD, 13.20 ± 26.6 days) than for the IG (mean ± SD, 10.08 ± 14.68 days) (P = .007). There was no difference for time loss due to injury based on field type (P = .341).

CONCLUSION

The FIFA 11+ significantly reduced injury rates by 46.1% and decreased time loss to injury by 28.6% in the competitive male collegiate soccer player (rate ratio, 0.54 [95% CI, 0.49-0.59]; P < .0001) (number needed to treat = 2.64).

Sports injuries profile of a first division Brazilian soccer team: a descriptive cohort study

Objective:

To establish the injury profile of soccer players from a first division Brazilian soccer team. In addition, we investigated the association between the characteristics of the injuries and the player's age and position.

Method:

Forty-eight players from a Brazilian first division soccer team were followed during one season. Descriptive statistics were used to characterize the injury profile. Spearman's tests were used to verify the association between the number and severity of injuries and the player's age. Chi-square test was used to verify the association between type of injury and player's position. Fisher's exact test was used to verify the association between the severity of injuries and player's position.

Results:

The incidence of injuries was 42.84/1000 hours in matches and 2.40/1000 hours in training. The injury severity was 19.5±34.4 days off competition or training. Lower limb was the most common location of injury and most injuries were muscular/tendinous, overuse, non-recurrent, and non-contact injuries. Player's age correlated with the amount and severity of muscle and tendon injuries. Defenders had more minimal injuries (1-3 days lost), while forwards had more moderate (8-28 days lost) and severe injuries (>28 days lost). Furthermore, wingbacks had more muscle and tendon injuries, while midfielders had more joint and ligament injuries.

Conclusion:

The injury profile of the Brazilian players investigated in this study reflected regional differences in soccer practices. Results confirm the influence of the player's age and position on the soccer injuries profile.

Injuries among amateur runners

Objectives

To determine the frequency and severity of injuries that affect amateur runners.

Methods

This study was conducted by means of a questionnaire applied to 204 amateur runners. Individuals who were under the age of 18 years and those who were unpracticed runners were excluded. The data gathered comprised the number, type, site and degree of severity of the injuries and the individuals’ age and sex.

Results

It was observed that male athletes predominated. The mean age was 32.6 ± 9.3 years with a range from 18 to 68 years, and the injuries were classified as mild, keeping the athlete away from practicing running for fewer than eight days. Sprains, blisters and abrasions were the most frequent injuries, located most often on the lower limbs and predominantly on the feet.

Conclusion

In practicing running, sprains, blisters and abrasions occur frequently, but are mild injuries. They mostly affect the lower limbs.

Relation between performance in side bridge and injuries in amateur soccer

AbstractIntroduction Central instability is associated with insufficient endurance and strength of the stabilizer muscles, and it can lead to muscle imbalance and injuries.Objective Relate side bridge performance with the presence of injuries in amateur soccer athletes.Materials and methods A cross-sectional study with a sample of 188 male athletes, aged between 11 and 17 years. To identify the injuries, a questionnaire developed by researchers was applied and the players’ clinical records were reviewed. The time of the side bridge test was used to identify muscle imbalance. For statistical analysis, the following tests were used: chi-square test; Pearson’s chi-square test; Fisher’s exact test; Yates’s correction for continuity; two-way ANOVA; one-way ANOVA; and t-test. The significance level (α) of 5% was adopted.Results Injuries were reported by 59.6% of the athletes: sprain (31.3%); muscle strain (28.6%) and fracture; luxation and subluxation (19.6%) were the most frequently reported injuries. Athletes that reported any injury corresponded to 73.2% of the sample. The presence of injuries was not associated with muscle imbalance (p = 0.565), as it prevailed in athletes with both balance (64%) and imbalance (58%). Injury type and prevalence were not significant when compared with the presence of imbalance (p > 0.05).Final considerations No significant relation between muscle imbalance and injury was observed in the studied sample.

Serious shoulder injuries in professional soccer: return to participation after surgery

PURPOSE

An evidence base for the management and prevention of shoulder injuries in soccer is lacking. The aim of this study was to demonstrate the type, mechanism and recovery time after surgery associated with serious shoulder injuries sustained in professional soccer to build an evidence base foundation.

METHODS

Fifty-two professional soccer players underwent shoulder surgery for injuries sustained during match play. Of these, 25 fulfilled the inclusion criteria. Data were collected for injury mechanism and type; clinical, radiological and surgical findings and procedures; and return to full participation. Subjects were all managed by the same surgeon.

RESULTS

Labral injuries represented the most common injury type affecting 21 (84 %) subjects; two rotator cuff (8 %) and two combined labral/rotator cuff (8 %) injuries were less common. Fourteen (56 %) subjects sustained a high-energy trauma injury in a combined abduction and external rotation position. Six (24 %) subjects sustained a low-energy trauma mechanism in variable positions, while five (20 %) had a gradual onset of symptoms. Twenty-two (88 %) subjects reported a dislocation as a feature of their presentation. All of the subjects with high- and low-energy trauma mechanisms reported a dislocation occurring at the time of injury. Eight (32 %) subjects had sustained a previous significant shoulder injury to the ipsilateral side. Goalkeepers did not sustain low-energy trauma injuries. Outfield players returned to full participation in a mean time of 11.6 weeks, while goalkeepers did so in 11.1 weeks post-surgery. Return to participation time ranged from 7 to 24 weeks with a median of 11 weeks.

CONCLUSION

Professional soccer players can expect a return to participation within 12 weeks post-surgery. The majority of serious shoulder injuries in soccer occur at a positional extreme of external rotation and abduction in high-energy situations, while a significant number occur in low-energy situations away from this position. Most serious shoulder injuries in professional soccer are dislocations. Previous shoulder injury is considered a risk factor.

LEVEL OF EVIDENCE

IV.