Four distinct patterns of anterior cruciate ligament injury in women's professional football (soccer): a systematic video analysis of 37 match injuries.

BACKGROUND: To identify mechanisms and patterns of anterior cruciate ligament (ACL) injury in adult women's professional football by means of video match analysis. METHODS: ACL match injuries sustained in Germany's first women's league during the 2016-2017 to 2022-2023 seasons were prospectively analysed by three expert raters using a standardised observation form. Epidemiological and injury data, as well as the medical history of ACL tears, were obtained from media reports and the statutory accident insurance for professional athletes. RESULTS: Thirty-seven ACL injuries sustained in official football matches were included in the video analysis, of which 24 (65%) had associated knee injuries, mainly meniscus and collateral ligament injuries. According to the categorised contact mechanisms, 17 (46%) were non-contact injuries, 14 indirect contact injuries (38%) and six direct contact injuries (16%). Of the 17 non-contact injuries, seven (41%) occurred during the first 15 min of the match. Contact mechanisms did not differ between primary and secondary ACL injuries to the same or the contralateral side. Most injuries (80%) of field players occurred during horizontal movements such as sprinting (n=9, 26%), change-of-direction manoeuvres (n=7, 19%), stopping (n=5, 14%) and lunging (n=5, 14%). Four distinct repetitive patterns of ACL match injuries were identified: (1) non-contact 'pressing ACL injury' (n=9), (2) indirect contact 'parallel sprinting and tackling ACL injury' (n=7), (3) direct contact 'knee-to-knee ACL injury' (n=6) and (4) non-contact 'landing ACL injury' (n=4). CONCLUSION: Most of the identified patterns of ACL injuries in women's professional football have great potential for prevention.

Training matters: Heading incidence and characteristics in children's and youth football (soccer) players.

OBJECTIVE: Concerns about short- and long-term consequences of repetitive heading contributed to heading restrictions in youth football in some countries. This prospective longitudinal cohort study aims to describe heading exposure in children's and youth football over two seasons using standardized video analysis. METHODS: All matches and training sessions of a male Under-11 (n = 29), Under-15 (n = 28), Under-19 (n = 38), and female Under-17 (n = 39) team were videotaped during the seasons 2019-2020 and 2020-2021. Heading frequencies and characteristics were analyzed. Individual heading exposure is presented as average incidence rates (IR) per 1000 match/training hours. RESULTS: In 275 matches and 673 training sessions, 22 921 headers were observed. Heading IR per player in matches was 1256 (Under-11 m), 1608 (Under-15 m), 1050 (Under-17 f), and 1966 (Under-19 m). In training sessions, IR per player was 739 (Under-11 m), 2206 (Under-15 m), 1661 (Under-17 f), and 1419 (Under-19 m). Five Under-15 males headed the ball five to eight times per training on average. Most headers were performed without heading duels. Flight distance was predominantly 5-20 m (54%) in matches and <5 m (65%) in training. While head impact location most frequently was at frontal areas, one-third of all headers in Under-11 in matches hit temporal, parietal, and occipital parts of the head. CONCLUSION: Heading incidence was low in the youngest age group, whereas (predominantly five) Under-15 males showed very high heading exposures in training. In assessment and regulation of heading burden, training sessions and individual heading behavior should specifically be addressed. Recommendations for heading the ball in practice should account for individual and age-related differences.

High revision arthroscopy rate after ACL reconstruction in men's professional team sports.

PURPOSE: The study analysed unique data on anterior cruciate ligament (ACL) injuries among German professional male team sports over five consecutive seasons with the aim of improving medical outcomes in the future. Sport-specific differences in injury occurrence, concomitant injuries, timing of ACL reconstruction, graft type selection and short-term complications were examined. METHODS: This retrospective study analysed trauma insurance data on all complete ACL tears from players with at least one competitive match appearance in the two highest divisions of German male basketball, ice hockey, football and handball. Each complete ACL tear registered by clubs or physicians between the 2014/15 and 2018/19 seasons with the German statutory accidental insurance for professional athletes (VBG) as part of occupational accident reporting was included. RESULTS: In total, 189 out of 7517 players (2.5%) sustained an ACL injury, mainly in handball (n = 82; 43.4%) and football (n = 72; 38.1%) followed by ice hockey (n = 20; 10.6%) and basketball (n = 15; 7.9%).Seventeen players (9.0%) also sustained a second ACL injury. Thus, 206 ACL injuries were included in the analysis. The overall match incidence of ACL injuries was 0.5 per 1000 h and was highest in handballs (1.1 injuries per 1000 h). A total of 70.4% of ACL injuries involved concomitant injury to other knee structures, and 29.6% were isolated ACL injuries. The highest rate of isolated ACL injuries was seen in ice hockey (42.9%). All ACL injuries, except for one career-ending injury, required surgery. In the four analysed team sports, hamstring tendons (71.4%) were the most commonly used grafts for ACL reconstruction; football had the highest percentage of alternative grafts (48.7%). During rehabilitation, 22.9% of all surgically treated ACL injuries (n = 205) required at least two surgical interventions, and 15.6% required revision arthroscopy. The main cause of revision arthroscopy (n = 32; 50.0%) was range-of-motion deficit due to arthrofibrosis or cyclops formation. CONCLUSION: The present study shows an overall high rate of revision arthroscopy after ACLR (15.6%), which should encourage surgeons and therapists to evaluate their treatment and rehabilitation strategies in this specific subpopulation. Hamstring tendon grafts are most commonly used for ACL reconstruction but have the highest revision and infection rates. Handball shows the highest ACL injury risk of the four evaluated professional team sports. Concomitant injuries occur in the majority of cases, with the highest share of isolated ACL injuries occurring in ice hockey. LEVEL OF EVIDENCE: Level III.

Reduced performance after return to competition in ACL injuries: an analysis on return to competition in the 'ACL registry in German Football'.

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.

High injury rates and weak injury prevention strategies in football referees at all levels of play.

Football referees need other physiological requirements on field than football players and are affected by different types of injury. The absence of referees may result in canceled matches, so special focus should be placed on injury prevention through specific training programs for referees. This study retrospectively analyzed injury occurrence and prevention strategies for German football referees at the different levels of play over one season. Data were collected by means of seasonal injury reports based on the consensus statement of injury definition and data collection. Of the 923 participating referees, 91 (9.9%) played at the professional level, 151 (16.3%) at the semi-professional, and 681 (73.8%) at the amateur level. 86.2% (n = 796) were men and 13.8% (n = 127) women. Referees at the amateur level showed the highest injury incidence (3.14/1000 h football) compared to referees at the semi-professional (1.92/1000 h; p < 0.001) and professional level (1.01/1000 h; p < 0.001). Most referees at the amateur (n = 372; 56.4%) and semi-professional level (n = 46; 31.3%) conducted warm-up programs of <10 min, whereas the mean warm-up duration of professional referees was >11 min (n = 75; 82.4%). Although running and stretching exercises were common among referees during warm-up, preventive exercises focusing on coordination and trunk muscles were less frequent, especially among amateur referees (jumping: 15.9%; strengthening: 9.7%; balance exercises: 7.9%). Injury incidence was highest at lower amateur levels, which thus has specific need for injury prevention. Appropriate training exercises to prevent injuries of referees were weak at all levels of play, especially the lack of strength, plyometric, and balance exercises in training and warm-up programs.

Increased occurrence of ACL injuries for football players in teams changing coach and for players going to a higher division.

PURPOSE: To identify football-specific factors associated with ACL injuries that can be targeted for sport-specific injury prevention. METHODS: A study-specific questionnaire was developed to study the characteristics of ACL injuries in football including intrinsic, extrinsic, and injury specific factors. The questionnaire was available at the Swedish national knee ligament registry's website for the football players to voluntarily fill out. Data are presented on group level for all football players in total and for females and males separate to examine gender-specific differences. The results are based on answers collected over a 3-year period from 2875 football players, 1762 (61%) males and 1113 (39%) females. RESULTS: ACL were more frequently sustained during games 66% than during practices 25%. The injury mechanism was non-contact in 59% and contact in 41%. For the contact injuries during games, no action was taken by the referee in 63% of the situation and a red card was shown in 0.5%. The risk of ACL injury was highest early in the football game with 47% sustained during the first 30 min and 24% in the first 15 min. Players changing to a higher level of play 15% had a higher rate of ACL injuries than players changing to a lower level 8%. This difference was especially seen in female football players with 20% of ACL injuries being sustained by players going to a higher division compared to 7% for those going to a lower division. 15% of the male and 21% of the female ACL injuries occurred in teams with a coach change during the season. Knee control exercises to warm up was used by 31% of the female players and 16% of the males. 40% of the players reported that they did not plan on returning to football. CONCLUSION: Neuromuscular training programs have proven to reduce ACL injuries, but greater adherence to these remains a challenge as only 1 in 5 of the ACL-injured football players report using them. Teams changing coach and players going to a higher division appear to have an increased risk of ACL injury warranting attention and further investigations. LEVEL OF EVIDENCE: IV.

Higher risk of ACL rupture in amateur football compared to professional football: 5-year results of the 'Anterior cruciate ligament-registry in German football'.

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.

Epidemiological analysis of injury occurrence and current prevention strategies on international amateur football level during the UEFA Regions Cup 2019.

INTRODUCTION: Football is the most popular sport worldwide and results in a high frequency of injuries. So far, mainly injuries in professional football have been investigated, and the literature lacks data regarding detailed injury epidemiology and current prevention data in amateur football tournaments. MATERIALS AND METHODS: A prospective cohort study investigated an international amateur football tournament, the UEFA Regions' Cup, which took place in 2019 in Germany. Injury epidemiology, current prevention strategies of the teams and the implementation of the UEFA concussion protocol were investigated in detail by means of standardized injury definitions and data samples for football (Fuller et al., Scand J Med Sci Sports 16:83-92, https://doi.org/10.1111/j.1600-0838.2006.00528.x , 2006). RESULTS: 138 player of 8 teams participated in this study, while 39 players were excluded. Overall injury incidence was 12.5 per 1000 h total football exposure, 43.5 per 1000 h for match exposure. No injuries were registered during training. Injury prevalence was 14.1% per player and 1.1 injuries per match were registered. The lower extremity was predominantly affected by injuries (71.4%) and the majority of injuries (78.6%) were non-severe injury types like contusions (50%) and sprains (18.2%). Two head injuries, one contusion and one skin lesion, were handled by the guidelines of the UEFA concussion protocol. 44.4% of the players indicated at least one previous injury before tournament, 45.3% of them during the last two football seasons before start of the tournament. Injury prevention performance was included in all participating teams during the tournament by warm up or training strategies (100%). During the warm-up program just 5 exercises of the FIFA 11 + program was detected by this investigation in participating teams to be done by more half of the teams. Running exercises were the most frequently performed exercises, while trunk muscle exercises were less represented (14.3%). CONCLUSION: This study presents for the first time epidemiological injury and prevention data of the UEFA Regions Cup. Injury incidence was higher compared to injury reports of regular seasons, but lower compared to other amateur football tournaments. Currently used prevention programs revealed trunk muscle exercises as often neglected.

Timing return-to-competition: a prospective registration of 45 different types of severe injuries in Germany's highest football league.

INTRODUCTION: Many professional football players sustain at least one severe injury over the course of their career. Because detailed epidemiological data on different severe injuries in professional football have been missing so far, this study describes the frequency and return-to-competition (RTC) periods of different types of severe football injuries. MATERIAL AND METHODS: This epidemiological investigation is a prospective standardised injury analysis based on national media longitudinal registration. Injuries were classified according to the consensus statement by Fuller et al. (2006). The analysis includes injuries sustained by players of the first German football league during the seasons 2014-2015 to 2017-2018. LEVEL OF EVIDENCE: II. RESULTS: Overall, 660 severe injuries were registered during the four seasons (mean 165 per season; 9.2 per season per team; incidence in 1000 h: 0.77). The body region most frequently affected by severe injury was the knee (30.0%; 49.5 injuries per season/SD 13.2) followed by the thigh (26.4%; 43.5 injuries/SD 4.2) and the ankle (16.7%; 27.5 injuries/SD 5.0). The distribution of injuries over the course of a season showed a trend for ACL ruptures to mainly occur at the beginning of a season (45.8%), overuse syndromes such as achillodynia (40.9%) and irritation of the knee (44.4%) during the winter months and severe muscle and ankle injuries at the end of a season. ACL ruptures showed the longest RTC durations (median 222 days). CONCLUSION: This study presents detailed epidemiological data on severe injuries in professional football. The body region most frequently affected by severe injuries was the knee. Several types of severe injuries showed a seasonal injury pattern. The appropriate timing of RTC after an injury is one of the most important and complex decisions to be made. This study provides information on the typical time loss due to specific severe football injuries, which may serve as a guideline.

No increased injury incidence in the German Bundesliga after the SARS-CoV-2 virus lockdown.

INTRODUCTION: The coronavirus lockdown in 2020 resulted in a worldwide suspension of professional sports. The first major professional football league to restart after the lockdown was the German Bundesliga. This study investigates whether the injury incidence increased after the restart of the season with only 9 days of regular preparation time and without any friendly matches in comparison to three control periods. MATERIALS AND METHODS: In a prospective cohort study, injury analysis (at least 1 day of absence from official football matches or training sessions) of the German Bundesliga registry was standardised according to Hägglund et al. (Br J Sports Med 39:340-346, 2005) and Fuller et al. (Clin J Sports Med 16:97-106, 2006) for data collection and to previous publications for the validated use of media sources for injury registration. The study period after the lockdown in May and June of the 2019-2020 season was compared to three control periods: the period directly before the lockdown, the beginning of the 2019-2020 season and the 2018-2019 season final. RESULTS: The nine match days after the restart of the 2019-2020 season showed an overall injury incidence of 4.9 per 1000 h football. This rate was significantly lower than that of the previous season final (9 last match days, overall injury incidence: 6.9 per 1000 h football; p < 0.001) and not increased compared to the rates after the summer break (9 match days; incidence: 5.5/1000 h, p > 0.05) or the winter break (8 match days; incidence: 5.6/1000 h, p > 0.05). CONCLUSION: The period after the unexpected break in the 2019-2020 season due to the coronavirus lockdown and the rapid return to competition showed no increase in the injury rate compared to the pre-lockdown period and a lower injury rate than in the previous season final. The unintentional mid-season rest with its potential for physical recovery and individual fitness training seems to have had a positive effect on injury occurrence.

Z-score values of left ventricular dimensions in adolescent elite male soccer players.

Recent studies showed contrasting findings in morphological changes due to competitive soccer in adolescent players (SP). We present a prospective study in 315 consecutive adolescent (10-14 years) male elite SP and 53 healthy matched active controls (CON). All participants underwent a complete transthoracic two-dimensional echocardiography (TTE). The mean age in SP was 12.8 ± 0.65 years compared to 12.6 ± 0.8 years in CON. For all left ventricular (LV) dimensions, mean Z-score values were higher in SP. There was a significant Z-score increase in interventricular septum diastolic diameter (2.47z vs. 1.62z, p < 0.05), left ventricular posterior wall diastolic and systolic diameter (1.15z vs. 0.47z, p < 0.05 and 1.05z vs. - 0.4z, p < 0.05). Athletes had significant greater LV mass indexed for BSA (94 ± 12 g/m2 vs. 81 ± 13 g/m2, p < 0.05). There was no significant difference in LV function or diameters. Conclusion: Our findings suggest that elite soccer training in adolescent male is a type of sport predominantly related to cardiac resistance remodeling. Adolescent SP may develop supernormal left ventricular wall dimensions (+ 2.0 to + 2.5z). If in SP Z-scores, any LV dimension above + 2.5 is measured, primary or secondary cardiomyopathies should be excluded. What is Known: • Morphological cardiac adaptation in response to exercise depends on the type, duration, and intensity of training. • Morphological and functional changes due to competitive sports (athlete's heart) occur even in pre-adolescent athletes. What is New: • Our findings point out that German elite soccer training in adolescent male (10-14 years of age) is a type of sport predominantly related to cardiac resistance remodeling. • If in an adolescent competitive soccer player any LV dimension Z-score value above + 2.5 is measured, a primary or secondary cardiomyopathy should be excluded.

Successful return to professional men's football (soccer) competition after the COVID-19 shutdown: a cohort study in the German Bundesliga.

OBJECTIVES: To evaluate the restart of the German Bundesliga (football (soccer)) during the COVID-19 pandemic from a medical perspective. METHODS: Participants were male professional football players from the two highest German leagues and the officials working closely with them. Our report covers nine match days spread over 9 weeks (May to July 2020). Daily symptom monitoring, PCR testing for SARS-CoV-2 RNA twice weekly, and antibody tests (on two occasions-early during the phase in May 2020 and in the week of the last match) were conducted. Target variables were: (1) onset of typical COVID-19 symptoms, (2) positive PCR results, and (3) IgG seroconversion against SARS-CoV-2. All detected seroconversions were controlled by neutralisation tests. FINDINGS: Suspicious symptoms were reported for one player; an immediate additional PCR test as well as all subsequent diagnostic and antibody tests proved negative for coronavirus. Of 1702 regularly tested individuals (1079 players, 623 officials members), 8 players and 4 officials tested positive during one of the first rounds of PCR testing prior to the onset of team training, 2 players during the third round. No further positive results occurred during the remainder of the season. 694 players and 291 officials provided two serum samples for antibody testing. Nine players converted from negative/borderline to positive (without symptoms); two players who initially tested positive tested negative at the end of the season. 22 players remained seropositive throughout the season. None of the seroconversions was confirmed in the neutralisation test. CONCLUSION: Professional football training and matches can be carried out safely during the COVID-19 pandemic. This requires strict hygiene measures including regular PCR testing.

Coronary artery z score values in adolescent elite male soccer players.

BACKGROUND: With the increased training loads at very early ages in European elite youth soccer, there is an interest to analyse coronary artery remodelling due to high-intensity exercise. DESIGN AND METHODS: Prospective echocardiographic study in 259 adolescent elite male soccer players and 48 matched controls. RESULTS: The mean age was 12.7 ± 0.63 years in soccer players and 12.6 ± 0.7 years in controls (p > 0.05). Soccer players had significant greater indexed left ventricular mass (93 ± 13 g/m2 versus 79 ± 12 g/m2, p = 0.001). Both coronary arteries origin could be identified in every participant. In soccer players, the mean diameter of the left main coronary artery was 3.67 mm (SD ± 0.59) and 2.61 mm (SD ± 0.48) for right main coronary artery. Controls showed smaller mean luminal diameter (left main coronary artery, p = 0.01; right main coronary artery, p = 0.025). In soccer players, a total of 91% (n = 196) and in controls a total of 94% (n = 45) showed left main coronary artery z scores within the normal range: -2.0 to 2.0. In right main coronary artery, a pattern of z score values distribution was comparable (soccer players 94%, n = 202 vs. controls 84%, n = 40). A subgroup of soccer players had supernormal z score values (>2.0 to 2.5) for left main coronary artery (9%, n = 19, p = 0.01) and right main coronary artery (6%, n = 10, p = 0.025), respectively. CONCLUSION: Elite soccer training in early adolescence may be a stimulus strong enough to develop increased coronary arteries diameters. In soccer players, a coronary artery z score >2.0-2.5 might reflect a physiologic response induced by multiannual high-intensity training.

Football-related injuries are the major reason for the career end of professional male football players.

PURPOSE: Little is known about the consequences of injuries on professional male football players' career and retirement period. The aim of this study is to investigate the impact of injuries that male professional football players endure during their career, reasons for the end of their career and the post-career phase of retirement. METHODS: In a retrospective cross-sectional cohort study, retired male professional football players of the German Bundesliga were investigated by a standardised questionnaire to analyse the history of injuries sustained during their professional football career, the reasons for ending their career, their current health status and their suggestions for future prevention strategies. RESULTS: Most of the 116 analysed players (n = 73 (62.9%)) stated an injury as the reason for ending their professional career. Relevant injuries were mainly located in the lower extremities (n = 587 (61.3%)) with a focus on the knee (p < 0.001) and ankle (p < 0.001). A significant majority of the participants who had retired due to injury described degenerative symptoms, such as pain or instability, and were diagnosed with osteoarthritis after retirement (p < 0.001). These players had also often been affected by symptoms of depression during their career, which had decreased significantly after retirement. Moreover, players who had not retired due to injury had significantly better overall health status and quality of life after retirement. CONCLUSION: Football-related injuries have a significant impact on the career end of professional male football players and their health status after retirement. Future prevention strategies need to particularly address injuries to the knees and ankles and to implement measures for preventing osteoarthritis after retirement. LEVEL OF EVIDENCE: Level III.

Injury epidemiology in men's professional team sports: is media analysis helpful?

INTRODUCTION: Epidemiological injury surveillance in professional sports is often based on online media analysis in order to collect necessary data. However, the validation of this study protocol is lacking. Therefore, this study aimed to identify the validity of injury surveillance in men's professional team sports based on media reports. METHODS: In a retrospective cohort study, the validity of media-data-relating injuries was investigated in participating teams of the highest two German divisions in men's professional basketball (BB) and handball (HB) in the season 2018/2019. Injury protocols completed by the team physicians were compared to those of sports media injury reports. RESULTS: The study population was composed of 133 athletes (54 BB and 79 HB). Of 343 injuries reported by the team physicians, 151 (44%) could be identified by means of sports media reports. Severe injuries (n = 75, 72%) were reported more likely in sports media compared to less severe injuries (n = 76, 32%, p < 0.00001). Odds ratio (OR) was 5.33 (95% CI 3.22-8.82). No differences regarding injury reporting could be seen between the two team sports. CONCLUSION: For severe injuries, media analysis may be a sufficient method for data collection in popular men's professional ball sports. An underestimation of true injury prevalence lies within the range of previous reported investigations concerning the validation of injury surveillance methods. Non-severe injuries could not be verified via media analysis in professional handball and basketball.

Contact - but not foul play - dominates injury mechanisms in men's professional handball: a video match analysis of 580 injuries.

AIM: We aimed to identify patterns and mechanisms of injury situations in men's professional handball by means of video match analysis. METHODS: Moderate and severe injuries (absence of >7 days) sustained in competition in one of six seasons (2010 to 2013 and 2014 to 2017) in men's professional handball were prospectively analysed with a newly developed standardised observation form. Season 2013 to 2014 was excluded because of missing video material. RESULTS: 580 injuries were identified: 298 (51.4%) contact injuries, 151 (26.0%) indirect contact injuries and 131 (22.6%) non-contact injuries. Head (87.5%), hand (83.8%), shoulder (70.2%) and ankle (62.9%) injuries were mainly sustained during direct contact. Typical contact injuries included collision with an opponent's upper extremity or torso, and ankle injuries mainly consisted of foot-to-foot collisions. A large proportion (41.7%) of knee injuries were caused by indirect contact, whereas thigh injuries mainly occurred (56.4%) through non-contact mechanism. Wing (56.9%) and pivot (58.4%) players had the highest proportion of contact injuries, whereas backcourt players had a high proportion of indirect contact injuries (31.5%) and goalkeepers of non-contact injuries (48.9%). The injury proportion of foul play was 28.4%. Most injuries occurred in the central zone between the 6-metre and 9-metre lines (26.1%) and during the last 10 min of each match half (OR 1.71, p=0.016). CONCLUSIONS: In men's professional handball in a league setting, contact - but not foul play - was the most common mechanism associated with moderate and severe injuries. Head, hand, shoulder and ankle injury were mainly sustained during direct contact.

Time before return to play for the most common injuries in professional football: a 16-year follow-up of the UEFA Elite Club Injury Study.

OBJECTIVES: The objective was to describe the typical duration of absence following the most common injury diagnoses in professional football. METHODS: Injuries were registered by medical staff members of football clubs participating in the Union of European Football Association Elite Club Injury Study. Duration of absence due to an injury was defined by the number of days that passed between the date of the injury occurrence and the date when the medical team allowed the player to return to full participation. In total, 22 942 injuries registered during 494 team-seasons were included in the study. RESULTS: The 31 most common injury diagnoses constituted a total of 78 % of all reported injuries. Most of these injuries were either mild (leading to a median absence of 7 days or less, 6440 cases = 42%) or moderate (median absence: 7-28 days, 56% = 8518 cases) while only few (2% = 311 cases) were severe (median absence of >28 days). The mean duration of absence from training and competition was significantly different (p < 0.05) between index injuries and re-injuries for six diagnoses (Achilles tendon pain, calf muscle injury, groin adductor pain, hamstring muscle injuries and quadriceps muscle injury) with longer absence following re-injuries for all six diagnoses CONCLUSIONS: The majority of all time loss due to injuries in professional football stems from injuries with an individual absence of up to 4 weeks. This article can provide guidelines for expected time away from training and competition for the most common injury types as well as for its realistic range.

Injury Incidence Rates and Profiles in Elite Taekwondo during Competition and Training.

This study aimed to investigate exposure adjusted injury incidence rates and profiles associated with training and competition in an elite taekwondo athlete population. 82 athletes were investigated for injuries over a period of 5 years. Individual fight time exposure for training and competition was recorded. The type and location of the injuries were classified and exposure-adjusted injury incidence rates (IIR) were calculated per 1000 h for training and competition. 66 athletes with a mean age of 19.3±4.2 years and 172 injuries were included in the final data assessment. The exposure adjusted IIR was significantly higher during competition (p<0.001) with a rate ratio of 6.33 (95% CI 4.58-8.69). Ankle and foot region as well as hand and wrist were most affected with significant higher IIR in competition (p<0.001). Joint injuries, fractures, and bruising occurred the most. Fractures occurred mainly to the hand and wrist region. Future investigations should focus on exposure adjusted injury data including analyses of the detailed mechanism leading to especially severe injuries to improve specific injury prevention in competition and promote evolution of protective gear.

Decreased external rotation strength is a risk factor for overuse shoulder injury in youth elite handball athletes.

PURPOSE: Overuse shoulder injuries are common in youth handball, but research is limited. The purpose of this study was to identify pre-season risk factors associated with overuse shoulder injuries in this population. METHODS: One-hundred and thirty-eight (70 boys and 68 girls) youth elite players (age 14.1 ± 0.8 years, height 175.2 ± 8.2 cm, weight 64.0 ± 9.6 kg) completed a pre-season screening protocol. Passive glenohumeral range of motion and maximum external (ER) and internal rotation (IR) strength were measured with a manual goniometer and a hand-held dynamometer. Scapular dyskinesia and maximum throwing velocity were also assessed. Players completed standardised questionnaires over the 2017-2018 season and reported any overuse shoulder symptoms. RESULTS: Decreased isometric and eccentric ER strength was identified as a risk factor for overuse shoulder injury, both for absolute (OR 10.70, 95% CI 1.2-95.6, p = 0.034) and normalised ER strength (OR 1.2, 95% CI 1.0-1.4, p = 0.015) and the ER:IR strength ratio (OR 1.2, 95% CI 1.1-1.5, p = 0.012). ER gain of more than 7.5° (p = 0.025) and GIRD of more than 7.5° (p = 0.014) were identified as risk factors for overuse shoulder injury in girls. Scapular dyskinesia (OR 1.1, n.s.) and maximum throwing velocity did not seem to contribute to injury risk. The average response rate was 63%. CONCLUSION: In elite youth handball, deficits in ER strength is a risk factor for overuse shoulder injury for both sexes; ER gain and GIRD are only risk factors for girls. Focused pre-season assessments may aid the identification of risk factors for shoulder overuse injuries and the application of specific programmes to reduce risk. LEVEL OF EVIDENCE: II.

Prevention of severe knee injuries in men's elite football by implementing specific training modules.

PURPOSE: Injury prevention of knee injuries by means of training and warm-up exercises has been investigated in several studies in amateur football. However, the number of investigations in elite football is limited despite the currently higher injury incidence of severe knee injuries. Therefore, the purpose of this study was to investigate whether specifically adapted preventive training modules may reduce severe knee injuries in elite football. METHODS: In a prospective controlled cohort study of elite football players in Germany, an injury prevention programme with 5 modules was implemented in the season of 2015-2016. The training modules were specifically adapted to this skill level and based on scientific evidence, team coach preferences, and the specific environment of this playing level. Of the 62 teams taking part in this study, 26 used the new trainings modules and 36 continued their standard programme as a control group. Success of the programme was documented by means of an injury report over one season. The primary outcome was reduction in severe knee injuries. RESULTS: A pre-seasonal investigation had identified five modules to be implemented in the training routine. Postural stability, mobilisation of lower extremity joints, leg and trunk stabilisation, jumping, and landing exercises as well as agility movements were incorporated into the programme to prevent severe knee injuries in elite football. Over the season, the study group (529 players) with the adapted training modules had sustained 52 severe knee injuries (incidence: 0.38 per 1000 h football exposure; prevalence: 9.8%) compared to 108 severe knee injuries in the control group (601 players) using the standard programme (incidence: 0.68 per 1000 h football exposure; prevalence: 18.0%; p < 0.05). The overall injury incidence for any other type of injury was comparable between the two groups (3.3 vs. 3.4 in h 1000 football, n.s.). CONCLUSION: Appropriate preventive training modules reduce severe knee injuries in elite football significantly. The key for the sustainability of preventive training measures are programmes specifically adapted to the demands of the playing level and to the preferences of the coaches LEVEL OF EVIDENCE: II.