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Background: To identify the potential role of humeral retrotorsion (HRT) and range of motion (ROM) as a risk factor for shoulder overuse injury in elite youth handball players. The hypothesis was that increased HRT is associated with an increased risk of shoulder overuse injury., Methods: Over 2 seasons, 258 elite youth handball players (52% boys; age:14 ± 0.8 years) were included. Preseason assessment included HRT and glenohumeral internal and external (ER) rotational ROM using ultrasound and a manual goniometer. Sports-specific adaptations between male and female athletes and the dominant and nondominant shoulder were calculated. In addition, players completed standardized questionnaires over the 2018-2019 or 2019-20 season and reported any shoulder overuse symptoms using the Western Ontario Shoulder Index questionnaire., Results: Comparing male and female players showed significantly decreased HRT and decreased internal ROM in the dominant side of male athletes (P ≤ .027). No other difference was found. Significant side-to-side differences between the dominant and nondominant shoulder were found for HRT, internal rotation, and ER, regardless of sex (P < .001). For total range of motion, only female athletes showed a significant increase in the dominant arm (P = .032). The dominant side showed a significantly higher glenohumeral internal rotation deficit in male athletes than in female athletes (10° ± 17° vs 5° ± 10°, P = .011). Adaptations in HRT, ER gain, and total range of motion gain were not significant. Over the course of the 2 seasons, 20 athletes reported shoulder overuse injuries. Although glenohumeral internal rotation deficit was borderline nonsignificant (P = .056), none of the parameters tested were significantly associated with shoulder overuse injuries., Conclusion: Despite significant side-to-side differences and sport-specific adaptations, individual preseason screening of humeral retrotorsion and soft tissue adaptations does not identify elite youth handball athletes at increased risk of shoulder overuse injury., (Copyright © 2024 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Purpose: While injuries among elite tennis athletes are extensively documented, a notable research gap exists regarding tennis injuries among club-level players. This study examines tennis injuries in German league players, with a particular emphasis on the impact of racquet properties and court surfaces, distinguishing between chronic and acute injuries., Patients and Methods: Retrospectively analyzing data from 600 tennis players over a 1.5-year period, a standardized questionnaire covered anthropometrics, injury characteristics, equipment usage, and court surface conditions., Results: The study identified 1012 tennis-related injuries, averaging 1.7 per player. Acute injuries predominantly affected the lower extremity (56%), with ankle injuries being the most prevalent, and ligaments were the most commonly affected structures (36.4%). Chronic complaints (reported by 364 athletes) focused on the upper extremity (63.2%), primarily tendon injuries (56.8%). Racket properties exhibited no significant impact on chronic upper extremity injuries., Conclusion: This study highlights a high incidence of acute lower extremity injuries, especially ankle ligament injuries, among German league tennis players. It offers crucial insights for devising targeted injury prevention strategies applicable to amateur, semi-professional, and professional tennis players, despite finding no significant link between racquet material and chronic upper extremity injuries., Competing Interests: The authors declare no conflict of interest., (© 2024 Krueckel et al.)

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., Competing Interests: Competing interests: CK and HB are employed by the VBG., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To compare the standard Yo-Yo intermittent recovery (IR) test and an agility Yo-Yo IR test with a higher number of change-of-direction movements to cardiorespiratory match performance., Methods: The study included 11 professional male handball players (age 24.5 [4.6] y) of a German second-league team. The performance parameters of the players of the seasons 2016-17 to 2018-19 were analyzed. The Yo-Yo IR test was compared to a Yo-Yo IR test with multiple multidirectional changes of direction in response to visual stimuli, which was conducted on a SpeedCourt (Yo-Yo SC IR). Peak oxygen uptake (VO2peak) and maximum heart rate (HRmax) were measured. Between-methods differences of individual athletes were quantified with Bland-Altman plots., Results: HRmax was not statistically different during the Yo-Yo SC IR test compared to the Yo-Yo IR test (181 [10] vs 188 [8] beats·min-1; P = .16). Agreement between the 2 tests was moderate for HRmax and good for heart rates >180 beats·min-1. Mean average VO2peak was 51.7 (3.9) and 50.9 (2.8) mL·min-1·kg-1 for the Yo-Yo SC IR test and the Yo-Yo IR test (P = .693), respectively., Conclusions: A Yo-Yo test with multidirectional changes of direction in response to visual stimuli yielded good agreement with the frequently used linear running tests and can be used to assess players' VO2peak. The HRmax achieved during this test should be used with caution.

Objective: Two-stage exchange with an antibiotic-loaded polymethylmethacrylate (PMMA) spacer is standard treatment for chronic periprosthetic joint infection of the shoulder. We present a safe and simple technique for patient-specific spacer implants., Indication: (Chronic) periprosthetic joint infection of the shoulder., Relative Contraindications: Known allergy against components of PMMA bone cements. Inadequate compliance for two-stage exchange. Patient is unfit to undergo two-stage exchange., Surgical Technique: Hardware removal, histologic and microbiologic samples, and debridement. Preparation of targeted or calculated antibiotic-loaded PMMA. Tailoring of patient-specific spacer. Spacer implantation., Postoperative Management: Rehabilitation protocol. Antibiotic treatment. Reimplantation after successful eradication of infection., (© 2023. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

The aim was to investigate side-to-side and sex differences of anterior and inferior capsule thickness (ACT, ICT) between the throwing and non-throwing shoulder (TS, NTS) in youth elite handball players. 125 youth female and male elite handball players (14.1±0.7yo) were assessed for ACT and ICT by ultrasound . ACT measurement was performed from anterior (3 o'clock) in upright position and for ICT from inferior (6 o'clock) in supine position. Measurements of ICT in the TS of all athletes (1.4±0.2 mm) differed significantly but marginally to those in the NTS (1.3±0.2 mm) ( p = 0.001). Female (1.2±0.2 mm vs. 1.3±0.2 mm; p = 0.007) but not male youth players (1.4±0.2 mm vs. 1.4±0.2 mm, p = n.s.) demonstrated slight differences in ICT in the TS compared with the NTS. Although significant, the thickness in the TS compared to the NTS was within the measurement accuracy of the ultrasonic assessment. No difference in ACT was observed in the TS (1.4±0.3 mm) compared to the NTS (1.4±0.3 mm) for both sexes (n.s.).In conclusion, the anterior and inferior capsule thickness in youth elite handball athletes is not or only marginally different between throwing and non-throwing shoulders.

Introduction: To date, there is no valid single test or battery of tests for informing return-to-play (RTP) decisions following an acute shoulder injury. The purpose of this exploratory study is to evaluate a diagnostic test battery based on a Delphi consensus at the time of unrestricted return to team training after acute shoulder injury., Methods and Analysis: Data for this prospective multicentre cohort study are collected at two measurement time points: when the respective physician clears the patient for RTP (t1) and 12 months after RTP (t2). The study participants are 18-35 years old athletes participating at a professional level in the following team sports: handball, basketball, ice hockey, soccer, volleyball and American football. Maximum comparability will be ensured via uninjured matched pair teammates. To assess the subjective assessment of shoulder functioning and the athlete's readiness to RTP, patient-reported outcome measures (Western Ontario Shoulder Instability Index, Quick-Disabilities of the Arm, Shoulder and Hand, Psychological Readiness of Injured Athlete to Return to Sport and Shoulder Instability-Return to Sport after Injury) will be completed. After a medical check-up with a range of motion and anthropometric measurements as well as clinical tests, the participants will perform a structured warm-up protocol. The functional tests comprise handgrip strength, upper quarter Y-balance test, isometric strength, closed kinetic chain upper extremity stability test, wall hop test, functional throwing performance index and the unilateral seated shot put test and isokinetic tests., Ethics and Dissemination: The results of this study will be disseminated through peer-reviewed publications and scientific presentations at national and international conferences. Ethical approval was obtained through the Institutional Review Board of Martin-Luther-University Halle-Wittenberg (reference number: 2022-016)., Trial Registration Number: DRKS00028265., Competing Interests: Competing interests: HB works for the sponsor of the study as an advisor in the prevention field of sport (prevention department) and IB as an advisor in the field of insurance and benefits (rehabilitation department). Both supervise research projects in their departments and accompany the project participants until successful completion of the study. This is usually defined as successful implementation and transfer of the study results into practice., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Aim: To evaluate the functional outcome of partial reconstruction margin convergence in the treatment of massive, irreparable posterosuperior rotator cuff tear (RCT)., Methods: This retrospective, single-center study included all patients that were operated by means of a partial repair and infraspinatus shift for a massive, posterosuperior cuff tear between 2009 and 2016, either in arthroscopic or mini-open technique. Outcome measures included sex- and age-adapted Constant Score (saCS), Western Ontario Rotator Cuff (WORC) Index, Disabilities of Arm, Shoulder and Hand Scores (DASH), and relative effect per patient (REPP)., Results: Fifty-six shoulders in 54 patients (mean age: 66 ± 7 years) were evaluated at a mean follow-up of 40 ± 9 months. The mean tear size was Bateman 3.1 ± 0.7 and Patte 2.3 ± 0.4. All clinical scores showed improvement. The saCS improved from 64.1 ± 13.4 to 90.4 ± 13.7 (p < 0.0001), the DASH score from 51.8 ± 9.4 to 10.2 ± 13.4 (p < 0.0001) and the WORC index from 47.1% ± 8.6 to 87.9% ± 13.7 (p < 0.0001). The abduction strength of the affected side (1.7 ± 1.6 kg) was not restored to the same level as the contralateral side (5.4 ± 2.7 kg, p < 0.0001)., Conclusion: Partial cuff repair for posterosuperior, massive cuff tears yields good clinical outcome with a low rate of complications and high proportion of good and excellent responders., Level of Evidence: Level IV, therapeutic case series., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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., (© 2022. The Author(s).)

Purpose: Anterior cruciate ligament (ACL) injuries are a common severe type of football injury. Injury prevention measures should be adapted to the respective type of sports and be based on sports-specific strategies. A football-specific ACL registry including prospective ACL injury data of both sexes and at different skill levels is lacking in the literature., Methods: In Germany, a prospective 'ACL registry for German Football' was implemented in the 2014-15 football season. Professional football leagues (1 st to 3 rd national league), semi-professional football leagues (4 th until 6 th leagues) and amateur football leagues (7 th league and below) were monitored regarding the incidence of ACL injuries, risk factors, general treatment and rehabilitation. After the registration of an injury, injured players were sent a standardised questionnaire., Results: Overall, 1,206 ACL ruptures were registered in the investigated population of more than 56,000 players, resulting in a prevalence of 2.1%. The highest prevalence was found in men's amateur football (2.7%) as well as in men's and women's professional football (2.1% each)., Conclusion: This football-specific ACL registry provides for the first-time longitudinal data about ACL injury patterns and treatment at all football levels. This report describes the considerations for data collection and presents first epidemiological results of 6 years of ACL injury registration.

A series of new mixed-substituted heteronuclear precursors with preformed Si-Ge bonds has been synthesized via a two-step synthesis protocol. The molecular sources combine convenient handling with sufficient thermal lability to provide access to group IV alloys with low carbon content. Differences in the molecule-material conversion by chemical vapor deposition (CVD) techniques are described and traced back to the molecular design. This study illustrates the possibility of tailoring the physical and chemical properties of single-source precursors for their application in the CVD of Si 1- x Ge x coatings. Moreover, partial crystallization of the Si 1- x Ge x has been achieved by Ga metal-supported CVD growth, which demonstrated the potential of the presented precursor class for the synthesis of crystalline group IV alloys.

Background and Objectives : The aim of the present study was to evaluate the efficacy of a multimodal pain therapy (MPM) regarding the objective parameter muscle strength of segment-dependent lower limb muscle groups before and after such a treatment. Materials and Methods : 52 patients with a history of low back pain and/or leg pain received standardized multimodal pain management. Strength of segment indicating lower limb muscles were assessed for each patient before and after ten days of treatment by handheld dynamometry. Results : Overall strength increased significantly from 23.6 kg ± 6.6 prior to treatment to 25.4 ± 7.3 after treatment, p ≤ 0.001. All muscle groups significantly increased in strength with exception of great toe extensors. Conclusions : Despite lower basic strength values at the beginning of treatment, all investigated muscle groups, except for the great toe extensors, showed a significant increase of overall strength after completion of the multimodal pain management concept. Increased overall strength could help with avoiding further need of medical care by supporting patients' autonomy in daily life activities, as well as maintaining working abilities. Thus, our study is the first to show a significant positive influence on lower limb strength in patients with low back pain after a conservative MPM program.

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., (© 2021. The Author(s).)

Objectives: Handball is associated with a high risk of overuse shoulder injury. This study investigated if an injury prevention programme effectively reduces overuse injury to the throwing shoulder of handball athletes., Methods: 61 men's and women's handball teams (u-19 and senior athletes) were cluster-randomised into an intervention and a control group in the 2019-2020 season. Players of the intervention group regularly carried out an injury prevention programme. Both groups documented overuse shoulder injuries via an online questionnaire every second week. The primary endpoint was the prevalence of overuse injury to the throwing shoulder. Secondary endpoints were the influence of compliance on the primary endpoint and intensity of overuse shoulder symptoms measured by a shortened, handball-specific Western Ontario Shoulder Index (WOSI)., Results: 31 teams (295 players) in the intervention group and 30 teams (284 players) in the control group were included for analyses. The overall questionnaire response rate was 61%. The average prevalence of overuse shoulder injury did not significantly differ between the intervention group (n=109, 38.4% (95% CI 32.9% to 44.2%)) and the control group (n=106, 35.9% (95% CI 30.7% to 41.6%), p=0.542). Compliance with the intervention programme did not significantly affect overuse shoulder injury (p=0.893). Using generalised estimating equations for WOSI, the estimated mean for the intervention group was 44.6 points (95% CI 42.0 to 47.1) and 47.6 points for the control group (95% CI 44.9 to 50.3, p=0.111)., Conclusions: A multicomponent exercise programme using rubber bands and stretching did not significantly reduce the prevalence or symptoms of overuse throwing shoulder injury in handball athletes of both sexes. Randomised controlled study; level of evidence I., Trial Registration Number: ISRCTN99023492., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.)

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., (© 2021. The Author(s).)

Background: To identify injury patterns and mechanisms in professional men's basketball by means of video match analysis., Methods: In Germany, injuries are registered with the statutory accident insurance for professional athletes (VBG) by clubs or club physicians as part of occupational accident reporting. Moderate and severe injuries (absence of > 7 days) sustained during basketball competition in one of four seasons (2014-2017 and 2018-2019) in the first or second national men's league in Germany were prospectively analyzed using a newly developed standardized observation form. Season 2017-2018 was excluded because of missing video material., Results: Video analysis included 175 (53%) of 329 moderate and severe match injuries. Contact patterns categorized according to the different body sites yielded eight groups of typical injury patterns: one each for the head, shoulders, and ankles, two for the thighs, and three for the knees. Injuries to the head (92%), ankles (76%), shoulders (70%), knees (47%), and thighs (32%) were mainly caused by direct contact. The injury proportion of foul play was 19%. Most injuries (61%) occurred in the central zone below the basket. More injuries occurred during the second (OR 1.8, p = 0.018) and fourth quarter (OR 1.8, p = 0.022) than during the first and third quarter of the match., Conclusion: The eight identified injury patterns differed substantially in their mechanisms. Moderate and severe match injuries to the head, shoulders, knees, and ankles were mainly caused by collision with opponents and teammates. Thus, stricter rule enforcement is unlikely to facilitate safer match play., (© 2021. The Author(s).)

Introduction/background: Surfing, wind surfing and kite surfing enjoy a growing popularity with a large number of athletes worldwide. The aim of this study was to identify and compare the injury profiles and compare the injury profiles of these three extreme water sports., Materials and Methods: These data for this retrospective cohort study were collected through an online standardised questionnaire during the 2017-18 season. The questionnaire included questions about anthropometry, skill level, injury diagnosis, injury mechanism, environmental conditions and training regimes., Results: The 626 athletes included reported 2584 injuries. On average, each athlete sustained 4.12 injuries during the season. The most frequent injury location was in the lower extremity, in particular the foot, with 49 (16.4%) injuries in surfing, 344 (18.3%) in wind surfing and 79 (19.7%) in kite surfing. Surfing demonstrated a particularly high rate of head injuries (n = 37; 12.4%). Other frequent injury types were skin lesions (up to 42.1%) and contusions (up to 40.5%). The most common injury across all surfing sports was skin lesions of the foot (wind surfing: 11.7%; kite surfing: 13.2%; surfing: 12.7%). In surfing, skin lesions of the head were frequently observed (n = 24; 8.0%). In surfing, a 'too large wave' (n = 18; 24.7%) was main cause of the injury, while in wind surfing (n = 189; 34.5%) and kite surfing (n = 65; 36.7%) 'own incompetence' led to the most injuries., Conclusion: This unique study compares injury epidemiology and mechanism in the three most popular surfing sports: wind surfing, kite surfing and surfing. Overall, injuries were sustained mainly in the lower extremity, while surfing also demonstrated a high rate of head injuries., Competing Interests: The authors report no conflicts of interest in this work., (© 2021 Szymski et al.)

Introduction: Hand and wrist injuries have been described as the second most common severe injuries in handball. However, no evidence exists regarding the specific characteristics of these injuries. The aim of this study was to determine the injury pattern of hand and wrist injuries in youth handball., Materials and Methods: Two-hundred and ninety-six adolescent elite handball players (mean age: 14.0 ± 0.8 years) completed a retrospective survey regarding their hand and wrist injuries during the previous season. The injury questionnaire was adapted from sports-specific questionnaires to the demands of hand and wrist injuries in handball and included injury location, type of injury and injury severity., Results: One-hundred and twenty-three (42 %) players reported 156 injuries (0.53 injuries per season per player) to their hands or wrists in the past season. Injuries to the proximal interphalangeal joints were most frequently described (n = 74, 47 %). The thumb was involved in 46 (29 %) cases. Sprains (n = 113, 72 %) were the most common type of injury. Thirty-six percent of moderate and severe injuries (> 7 days time loss) had not been treated by a physician., Conclusions: The rates of hand and wrist injuries are high in youth elite handball. Injury prevention strategies and return to competition criteria should focus on the thumb and the interphalangeal joints. Further research into these injuries is essential to identify risk factors and to develop adequate injury prevention measures., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: The aim of this review was to compare clinical and radiological outcome of acromio-clavicular joint reconstruction with allografts versus autografts., Methods: The PubMed, MEDLINE, The Cochrane Library and WEB OF SCIENCE databases were searched in accordance with the PRISMA guidelines until February 2020 using the terms: 'coracoclavicular' OR 'coraco-clavicular' OR 'acromioclavicular' OR 'acromio-clavicular joint', AND 'reconstruction'. All studies reporting on clinical and radiological outcome as well as complications after ACJ reconstruction using allo- and/or autografts were included., Results: A total of 29 articles, including 2 prospective and 27 retrospective studies, involving 622 patients, reconstructed with either allo- (n = 360) or auto-grafts (n = 262), for acromio-clavicular joint instability were identified and included in this review. The majority of studies had low sample sizes (66.7% below n = 20), were retrospective (93.3%), with short-term follow-ups (average 26.2 ± 12.6 months; range 6-186). The study with the largest sample size (n = 128) did not report clinical outcome. A comparison between allo- and auto-graft showed no significant differences regarding age, gender, and follow-up times. Clinical outcome was comparable in both groups, loss of reduction (LOR) and complication rates were higher in the allograft group. Overall a reduction of LOR was shown if additional horizontal stabilization was performed. Also a higher LOR and revision rate was documented in allografts without suture or suture-tape augmentation. The use of more clavicular drill-holes correlated with a higher frequency of fracture., Conclusions: A systematic review of the available peer-reviewed literature addressing allograft and autograft reconstruction of unstable coracoclavicular ligaments shows that the published studies are generally of low quality with low levels of evidence. The published literature shows no significant difference in clinical outcomes between the use of autografts or allografts in ACJ reconstruction surgery. Surgical techniques utilizing additional horizontal stabilization may contribute to lower rates of LOR. In cases where allograft tissue is used for ACJ reconstruction the use of suture/tape augmentation may reduce LOR rates as well as revision rates., Level of Evidence: III.

Introduction: Bouldering has become a sport of growing interest, but little prospective evidence exists about injury proportions and patterns. The purpose of this study was to prospectively evaluate the cause of injuries sustained during indoor bouldering, proportion of affected body location, and injury severity., Methods: Proportions and patterns of injury among German-speaking indoor boulderers were evaluated prospectively in an explorative cohort study. Participants completed a baseline questionnaire assessing anthropometric data and sport-specific potential preventive and risk factors, followed by monthly injury questionnaires including injury location and injury severity over a period of 12 mo., Results: Out of 507 boulderers, 222 (44%) sustained 305 injuries. Of those, 78% (n=238) were classified as Union Internationale de Associations d'Alpinisme (UIAA) 1, 19% (n=57) as UIAA 2, and 3% (n=10) as UIAA 3. Injuries of the upper extremities accounted for 63% (n=191) of all injuries. Injuries of the lower extremities accounted for 23% (n=71) but were more often classified as UIAA≥2 (P=0.0071; odds ratio [OR] 2.23; 95% CI 1.23-4.04) and were more often caused by falling (P=0.0005; OR 2.92; 95% CI 1.57-5.42) and jumping off the wall (P<0.0001; OR 4.39; 95% CI 2.25-8.56) than injuries of other body locations. There was no statistically significant protective effect of the evaluated potential preventive measures. Participants who used heavily downturned climbing shoes had a higher risk of sustaining a UIAA ≥2 injury (P=0.0034; OR 2.58; 95% CI 1.34-4.95)., Conclusions: Injuries in indoor bouldering are common. Lower extremity injuries are associated with higher injury severity. Preventive measures need to be established to reduce bouldering injuries, especially during falls and landings., (Copyright © 2021 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.)

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.

Background: Superior capsular reconstruction (SCR) represents a new option for the treatment of irreparable rotator cuff tears., Purpose/hypothesis: This study aimed to evaluate the clinical and radiologic outcomes of SCR and compare them with the outcomes of partial repair (PR) of the infraspinatus tendon. The hypothesis was that there would be no significant differences between the clinical and radiologic outcome parameters of SCR and PR after a minimum follow-up of 2 years., Study Design: Cohort study; Level of evidence, 3., Methods: Of 21 patients who underwent SCR, 20 patients were matched in a 1:1 ratio according to sex, age, and tear configuration with 20 of 60 patients who had undergone PR; all patients were prospectively evaluated for a minimum follow-up of 2 years. The investigated outcome measures included the Constant score; Western Ontario Rotator Cuff (WORC) index; Disabilities of the Arm, Shoulder and Hand (DASH) score; and radiologic analysis of acromiohumeral distance (AHD) and humeral head centralization (HHC)., Results: There were no differences in the demographic data between the SCR and PR groups. The mean age of both groups was 62.3 years (range, 47-79 years), the mean tear configuration was Bateman 3.0 and Patte 2.8, and the mean follow-up period was 29.4 months (range, 24-53 months). At final follow-up, no significant differences were seen between the SCR and PR groups with regard to Constant score (77.1 vs 82.7), age- and sex-adapted Constant score (85.5% vs 91.4%), DASH score (15.6 vs 7.8), or WORC index (81.1 vs 90.4). No significant differences in the AHD or HHC were seen between the groups. The reoperation rate was 4.8% (1/21) in the SCR cohort and 15% (9/60) in the PR cohort., Conclusion: Both SCR and PR resulted in significant improvements in patient-reported outcomes at 2-year follow-up, with no significant differences in clinical outcomes between the 2 techniques. Further follow-up is needed to determine whether there are long-term differences in HHC and development of cuff tear arthropathy. Further investigations should also focus on the cost-effectiveness of the respective procedures., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: S.G. and M.K. are medical advisors for Arthrex GmbH. A.V. is a consultant for DJO Global. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2021.)

Purpose: Range of motion adaptations in the shoulders of overhead throwing athletes have been reported, but knowledge about the development of soft-tissue adaptations is limited. The purpose of this study was to investigate differences in posterior shoulder capsule thickness and internal rotation between the throwing and non-throwing shoulder., Methods: On the basis of the sample size calculation, we assessed 63 youth elite handball players (33 boys and 30 girls, mean age: 13.6 ± 0.9 years) for glenohumeral internal and external rotational range of motion, humeral retrotorsion, and posterior capsule thickness (PCT) with a manual goniometer and a portable ultrasound device and calculated sports-specific differences between the throwing and non-throwing shoulder as well as correlations with PCT., Results: Youth handball players showed side-to-side differences in internal rotation, external rotation, and humeral retrotorsion between the throwing and non-throwing shoulder. Posterior shoulder capsules were 1.21 times thicker (95% confidence interval: 1.1-1.3) in the throwing shoulder than in the non-throwing shoulder (1.3 ± 0.3 mm vs. 1.2 ± 0.2 mm, P < .0001). Loss of internal rotation did not correlate with PCT., Conclusions: In youth elite handball athletes, posterior shoulder tightness and subsequent sports-specific loss of internal rotation in the throwing shoulder are not related to PCT. Thus, in this age class, other (soft-tissue) factors must be responsible for this condition., (Copyright © 2020 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Purpose: Small-field soccer is a popular type of amateur sports worldwide. One type of small-field soccer growing in popularity is bubble-soccer, but injury risks and injury patterns are still unclear. This study investigates the factors influencing injuries in bubble-soccer for the first time., Materials and Methods: This prospective cohort study of an outdoor tournament investigated the injury incidence and injury patterns as well as the factors influencing injuries in bubble-soccer matches. Data were collected according to the statement on data collection and injury definition. Preparation and physical outcome were assessed for both sexes., Results: Of 145 players (104 men, 41 women), 58 players sustained 94 injuries during the tournament and 64% of injuries affected the lower extremities. The most common traumatic injuries were skin lesions (37.5%), acute pain (15.6%) and contusion (7.8%). More female players (3818.2/1000 h bubble-soccer) than male players (1474.4) were affected by injury, mostly to the knees or the head. Also, women significantly more often reported neck pain than men (p<0.042); 29.0% of players felt uncomfortable wearing the bubble, and 21.4% reported neurological symptoms such as headache or dizziness after the match., Conclusion: Bubble-soccer shows a relatively high injury incidence. Women had a higher injury incidence and were more often affected by traumatic injuries to the head and neck including feeling of discomfort and headache or neck pain after the match. Adequate preparation seems to be essential for injury prevention, and players should recognise the high injury risk of bubble-soccer., Competing Interests: The authors report no conflict of interest in this work., (© 2020 Krutsch et al.)

Purpose: Injury data of professional soccer players obtained from media reports are frequently used in scientific research, but the accuracy of such data is still unclear., Patients and Methods: Injuries of professional soccer players of the German first and second league were documented by continuously screening media reports over one season (2015-2016). After the season, the validity of media-reported injuries was anonymously analyzed by the team physicians of 8 different soccer clubs., Results: A total of 255 injuries of 240 players of 8 professional soccer teams had been published online, of which 146 were confirmed by the team doctors as correct, yielding a rate of 57.3% of confirmed media-reported injuries. In addition, 92 injuries without media registration were detected and added to the online statistics, resulting in 347 injuries and an overall weak validity of media-based data of 42.1%. Statistical analysis showed that the validity of media-reported injury data depended on both the individual soccer club and the body site affected by injury: publications on knee injuries (78.2%) had a higher validity than those on foot injuries (46.2%), and publications on severe injuries had a higher validity (joint dislocation: 100%; ligament rupture: 82.9%; fracture: 73.3%) than those on minor injuries. Publications on specific severe soccer injuries, such as anterior cruciate ligament (ACL) injuries, had a validity of 100%., Conclusion: Media-based injury data were only valid for a few severe injury types such as ACL injuries. In daily soccer routine and scientific research, media-based data should thus only be used in combination with specific criteria or verification processes., Competing Interests: Werner Krutsch reports being a member of medical committees in different football associations: German Football Association, German Football League and Bavarian Football Association but states all memberships are no conflict of interest to this study and this article. The authors report no other conflicts of interest in this work., (© 2020 Krutsch et al.)

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., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Handball is characterised by a high rate of injuries. Recent epidemiologic studies, which take the characteristics of handball into account, demonstrate a clear picture of injury patterns and injury risks for handball athletes. While more than half of all athletes can continue playing handball after medical treatment, the other half of injuries is accompanied by loss of training and match time. Although the sustained injuries are associated with a contact mechanism, they are not related to a high rate of foul play in the league setting. This shows that there is a high potential for prevention. Handball medicine strongly aims to primarily reduce and thus prevent injuries in this sport. The existing evidence for the potential of prevention of severe knee injuries must now be implemented into daily training. Due to the high prevalence of overuse injuries to the throwing shoulder, here, too, the first insights have been implemented in a prevention programme. This is described in detail in this article., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

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.

Introduction: Amateur small-field football tournaments are rather common worldwide. Adequate preparation is essential for injury prevention. The consequences of insufficient injury preparation at this level are still unclear. This study investigates the factors influencing injuries in this football population., Materials and Methods: In 2017, medical students participating in a national amateur football tournament were analysed in a prospective cohort study. Injury incidence, injury pattern and factors influencing injuries were investigated according to the statement on data collection and injury definition of Fuller et al. (Br J Sports Med 40:193-201, 2006). Preparation for the tournament was assessed for both sexes by means of hours of sleep, alcohol consumption, training level and warm-up performance., Level of Evidence: II., Results: Of 694 amateur football players (423 men and 271 women) with a mean age of 23 years (SD 2.5), 321 (21.1%) injuries happened during the tournament. 60% of injuries affected the lower extremity. The most common types of traumatic injury were skin abrasions (40.0%) and muscle strains (23.3%). The injury incidence of male players during match exposure was 469 per 1000 h football and significantly higher than in female players 313 (p = 0.025). One potential reason for the higher injury rate of male players as measure for inadequate preparation was significantly higher alcohol consumption the evening before the tournament (p < 0.001) and the after-effects on match day (p < 0.001). Additionally, male players reported less and inadequate sleep the night before the tournament (p < 0.007) and a lower warm-up rate before the matches compared to female players (p < 0.001)., Conclusions: Small-field tournaments in football have a high injury incidence. Male players have a higher injury incidence than female players and show additionally a lack of sleep and alcohol consumption the night before the tournament and poor warm-up performance on match day. Adequate preparation for a football tournament is the key factor for preventing injuries, also in recreational football.

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.

Purpose: In youth handball players, knowledge about the development of soft-tissue adaptation and humeral retrotorsion is limited. The purpose of this study was to investigate differences in adaptations in the glenohumeral rotational range of motion and humeral retrotorsion of the throwing arm between male and female youth elite handball players., Methods: One-hundred and thirty-eight youth elite handball players (mean age: 14.1 ± 0.7 years) were assessed for glenohumeral external (ER) and internal (IR) rotational ranges of motion and humeral retrotorsion (HRT) by means of a manual goniometer and a portable ultrasound device. Sports-specific adaptations between the dominant and non-dominant shoulders and between male and female adolescents were calculated., Results: Handball players showed side-to-side differences in IR and ER in the throwing shoulder. HRT did not correlate with the measurements of rotational ROM of the throwing arm. Male athletes showed a more pronounced glenohumeral internal rotation deficit than female athletes (13.1° ± 22.8° vs. 5.1° ± 14.0°, p = 0.014). Adaptations in HRT but no sex differences could be seen in the throwing shoulder (16.5° ± 9.6°) compared to the non-throwing shoulder (13.5° ± 9.4°, p < 0.001)., Conclusion: Loss of internal rotation and gain in external rotation in youth handball players seem to be more related to adaptive changes in the soft-tissues than to HRT. Male athletes showed stronger throwing-related adaptations in the rotational range of motion but not in humeral torsion in their dominant shoulder than female athletes., Level of Evidence: Cross-sectional study, Level II.

Objectives: The first main goal of this study was to investigate the prevalence of depression and anxiety as well as self-compassion in a heterogeneous sample of male amateur soccer players. The second main goal of this study was the examination of the relationship between injuries and psychological factors in amateur soccer players., Methods: Players were recruited from German amateur soccer clubs of the fourth to seventh league. 419 soccer players with the mean age of 22.88 years participated in the psychological and the injury assessment at the beginning of the season and at the end, 9 months later. For the psychological assessment, depression and anxiety rate as well as self-compassion was analysed. Furthermore, the frequencies of injuries were registered., Results: The results showed that players of the highest amateur league, the fourth league in German soccer, showed significantly higher anxiety values than players from a lower league (p=0.013). There were no differences in depression values dependent on the league. Furthermore, players who suffered from an injury before the start of the season demonstrated higher anxiety values (p=0.027). This result was independent of the respective league., Conclusion: The results of this study demonstrate that even in higher amateur soccer the anxiety level of the players varies between soccer players of different leagues. Because an injury before the start of the season influenced the anxiety level, a psychological treatment during injury should be considered., Competing Interests: Competing interests: None declared.

Purpose: Injuries are a common occurrence in football. Sufficient epidemiological data are available in professional football but not in salaried semi-professional football. This study investigates the injury incidence at different levels of semi-professional football with focus on junior football., Methods: The data were based on injury reports provided by players and medical staff over the 2015-2016 season, which corresponded to the consensus statement for data samples in football. This study investigated the injury incidence and prevalence of five skill levels of semi-professional football (the fourth to the seventh league and elite junior football)., Results: 1130 players had sustained 2630 injuries over the 2015-2016 season. The overall injury incidence was 9.7 per 1000 h football exposure; prevalence with at least one injury was 79%. The highest overall injury incidence in elite junior football was 10.4 in 1000 h football exposure. The fifth league had the lowest incidence with 9.0 in 1000 h football (p < 0.05). Traumatic injuries most often occurred in the fourth league (3.9 in 1000 h football). The body areas most affected by traumatic injury were knees, ankles and thighs. Elite junior players had a significantly higher incidence of overuse complaints (7.4 in 1000 h football) than the fourth league (5.4, p = 0.005). The body areas most affected by overuse complaints were the lower back, thigh and groin. No differences were found between the different positions on field., Conclusions: Salaried semi-professional football involves a high overall injury incidence. The highest incidence, particularly of overuse injuries, was seen in elite junior football. These findings should be incorporated in specific injury prevention training or screenings beginning in junior football. Level of evidence II.

Purpose: Side-to-side asymmetry in side-cutting manoeuvres is a known risk factor for severe knee injury. Potential leg asymmetry during ground contact times of different change-of-direction manoeuvres was evaluated in athletes by means of the recently developed SpeedCourt ® system. The hypotheses were that ground contact times and the limb symmetry index are affected by age and the type of sports., Methods: One-hundred and sixty-five athletes (149 men, 16 women, age 16.5 ± 5.1) of popular team sports such as football, team handball and baseball were assessed by means of three different tests [side-hop, lateral change-of-direction (COD) and diagonal COD] using the SpeedCourt ® system. Analysis included the factors age, sex, type of sports, ground contact time, leg symmetry index and limb dominance., Results: During lateral but not diagonal COD tests, football players had shorter contact times than players of team handball (p = 0.026) and baseball (p = 0.015) of the same age group. The side-hop tests yielded differences in the leg symmetry index between players < 16 years and players > 16 years (p < 0.01). Mean ground contact time differed in each of the side-hop, lateral COD and diagonal COD tests (143.5 ± 20.0 vs. 256.2 ± 66.1 vs. 320.4 ± 55.0). Contact times and test durations of side-hop, lateral COD and diagonal COD tests were shorter for older players (p < 0.01)., Conclusions: Ground contact times of side-hop and change-of-direction manoeuvres are influenced by age, the type of sports and limb dominance. Such information is fundamental for future sports medicine research and needs to be considered in pre-season screening or when used as a criterion for return-to-competition of players with previous severe knee injury. Assessment of change-of-direction manoeuvres should be included in future return-to-competition test batteries., Level of Evidence: III.

The historical treatment options for partial anterior cruciate ligament (ACL) ruptures were conservative therapy or ACL reconstruction by injured bundle or entire ACL replacement. In awareness of the regenerative potential of biologic agents such as mesenchymal stem cells or platelet rich plasma (PRP), the healing response technique was developed to preserve the injured ACL with better outcomes than the conservative therapy. Further improvement of this technique seems to be obtained by the additional application of PRP products. Thus, the aim of this study was to evaluate the midterm outcome after intraligament autologous conditioned plasma (ACP) by a clinical, scoring, and functional performance assessment. 42 patients were evaluated in this study. The failure rate was 9.5%. Outcome evaluation showed good to excellent results. The scores were IKDC subjective 83.2 (SD 14.5), Lysholm 85.5 (SD 15.5), Tegner 4.7 (SD 1.7), and Cincinnati 85.4 (SD 15.5) after a mean follow-up of 33 months. Clinical examination showed stable Lachman test, negative pivot shift phenomenon, and a significant reduction in AP-laxity compared to preoperative status (rolimeter preoperative: 1.9 (SD1.4); postoperative 0.6 (SD1.8), p=0.001) in all patients. Functional performance testing showed no significant differences between the injured and healthy side. Return to sport was achieved after a mean of 5.8 months (SD 3.6) in 71.1% of the included patients. In summary, this new treatment option revealed in midterm follow-up promising results to treat partial ACL lesions with a reduced need for conversion to ACL reconstruction and with a high percentage of return to preinjury sport activity.

Purpose: Scientific injury data in men's professional team handball injuries are rare and even less scientific information exists on injury prevention. In 2011, Germany's national second team handball league was restructured by merging the existing two regional leagues into one league. This study evaluates the injury patterns in professional team handball and compares the injury rates between the first and second league before and after the restructure., Methods: All players of Germany's national first and second men's team handball leagues have mandatory trauma insurance with the same insurance company. This retrospective cohort study analysed the injury data of three consecutive seasons 2010-2013 using standardized injury definitions., Results: 1194 professional team handball players were included in this study. The majority of severe injuries affected the lower extremities, shoulders, and hands. The average injury incidence significantly differed between the first (4.9 injuries per 1000 h) and the second league (3.9 per 1000 h, p < 0.01). The injury incidence in the restructured second league had increased from 3.7 to 4.1 per 1000 h (p < 0.01) and prevalence from 67.1 to 79.3% (p < 0.001), thus almost to the same levels of the first league. The second league showed more time-loss injuries at all severity levels., Conclusion: This study yielded a high injury incidence after the restructure of the national second team handball league and presents details on prevalence, incidence, and patterns of injury in professional men's team handball. This study is an important basis for developing injury prevention strategies that should focus on the shoulders, hands, and lower extremities and on reducing the number of matches and travel burden., Level of Evidence: III.

Introduction: Injuries are a common problem in football. To improve prevention strategies, the players' (p) and coaches' (c) views need to be disclosed as they have a strong impact on return to play decisions. The aim of this study is to reveal current opinions with regard to injury prevention and return to play strategies to introduce new strategies in elite football., Materials and Methods: In a retrospective data analysis of elite salaried football players (n = 486) and team coaches (n = 88), a detailed investigation by means of a standardized questionnaire was carried out. In a preseason period of the 2015/16 season and as part of a large interventional research project in elite salaried German football, a request about players' and team coaches' knowledge and opinions was performed. Topics such as injury prevention, return to play after injuries, the importance of screening tests, general problems of injuries in football, or the decision-making in terms of prevention and return to play in elite football were investigated., Results: The study revealed a high interest in injury prevention and screening tests among players and coaches (p 82.5%; c 99.1%). The participants of the study reported warm-up exercises (p 76.4%; c 74.7%), regeneration training (p 54.1%; c 56.3%), and core stability (p 53.8; c 70.1%) as the most important prevention methods, but the additional investigation of the teams' current daily training routine showed that the transfer is incomplete. Coaches are more familiar with scientific published warm-up programs like FIFA 11 + than players (42.5 vs. 12.6; p < 0.001). Knee injuries (p 90.7%; c 93.1%) and ACL injuries in particular were reported as the most severe and common problem in elite football. Players and coaches expressed different attitudes concerning return to play decisions. While players want to decide themselves (81.4%), team coaches consult medical advice ahead of the decision of return to play after injuries (83.5%; p < 0.001). Decisions against the doctor's recommendation are often made by both groups (p 64.4% vs. c 87.1%; p < 0.001)., Conclusion: The basic knowledge of prevention and injuries is sufficient in elite football, but the transfer from theoretical knowledge to practical routine is suboptimal. The study also shows possibilities to improve the prevention process and communication between players, coaches, doctors, and physiotherapists, while there is no consent between players and coaches regarding return to play decision.

Purpose: Beach handball is a relatively new type of sports, which was derived from team handball. Medical issues such as frequency and severity of injury are yet unknown. The purpose of this study was to investigate the injury pattern and injury rates of this new type of sports., Methods: This study investigated the injury incidence of 30 national teams (10 senior and 20 u-17 teams, 16 men's and 14 women's teams) participating in the 2017 European Beach Handball Championships. Reports on injuries sustained during the senior and u-17 youth tournaments were provided by the medical staff of each team. Injury incidence was differentiated between age and sex, and between the five field positions (goalkeeper, wing, central defender, pivot, and specialist)., Results: During the tournaments, 87 injuries were recorded yielding an overall injury incidence of 286.1 per 1000 match hours. Time-loss due to injury was 49.3 per 1000 match hours. Senior players had a higher overall injury incidence with 395.3 injuries than u-17 players with 205.7 injuries per 1000 h match hours (p < 0.01). Comparison of the injury incidence between the two sexes showed 330.23 injuries per 1000 h handball exposure for male players and 234.9 injuries for female players (n.s.). The most frequent injury type was sprains (21 injuries, 24.1%) followed by contusions (19 injuries, 21.8%) and skin abrasions with (15 injuries, 17.2%). Central defenders and specialists had the highest injury incidence. Thighs, ankles, as well as foot and toes (altogether 12 injuries, all 13.8%) were the three most frequently injured anatomic sites., Conclusions: Beach handball seems to have a lower incidence of time-loss injuries than that reported for indoor team handball. This study is an important basis for developing injury prevention strategies in this sports that should focus on thighs, ankles, feet and toes. Further research into this new type of sports is essential to identify risk factors and to develop adequate injury prevention measures., Level of Evidence: II.

Purpose: Team handball is associated with a high risk of severe knee injury that needs to be reduced, particularly at the youth level. The purpose of this study was to show how an injury-prevention programme effectively reduces severe knee injury in adolescent team handball players., Methods: Of 23 adolescent handball teams of both sexes, 13 were randomly allocated into the intervention group (168 players) and 10 into the control group (111 players). Players of the intervention group regularly participated in an injury-prevention programme for one season. Handball exposure and sustained injuries were documented for both groups on a monthly basis. The primary outcome parameter of the injury-prevention programme was the incidence of severe knee injury., Results: Of the 279 included players, 68 (24%) sustained 82 injuries yielding an overall incidence of 1.85 injuries per 1000 h handball exposure (intervention group: 50 injuries/incidence: 1.90/1000 h; control group: 32 injuries/incidence: 1.78/1000 h). Knee injury was the second most frequent injury in adolescent team handball. The primary outcome parameter, severe knee injury occurred significantly more often in the control group [mean age (SD) 15.1 (1.0), injury incidence 0.33/1000 h] than in the intervention group [mean age (SD) 14.9 (0.9), injury incidence 0.04/1000 h]. The odds ratio was 0.11 (95% CI 0.01-0.90), p = 0.019. Other injuries to the lower extremities showed no significant difference between the two groups., Conclusions: Frequent neuromuscular exercises prevent severe knee injury in adolescent team handball players and should thus be included in the practical routine as well as in the education of team coaches.

Introduction: Conservative treatment of partial ACL ruptures is associated with a high failure rate, and often patients undergo ACL reconstruction. ACL preservation by trephination of the ACL origin and application of Autologous Conditioned Plasma (ACP) seems to be an intriguing new treatment option to favour ACL tissue healing and avoid traditional reconstruction. The aim of this study was to describe the mid-term outcomes of this new ACL preserving technique., Materials and Methods: Twenty-four patients (mean age 41.8 years) affected by partial rupture of one or both ACL bundles were included in the present trial. The partial ACL tears were arthroscopically assessed and classified according to a new five step grading system. All patients were treated by trephination of the femoral ACL stump and intra-ligamentary application of ACP. The postoperative outcome was evaluated by both subjective scores and stability testing up to a mean of 25.1 months' follow-up. Adverse events and failure rate were also documented., Results: Clinical outcome was good to excellent with IKDC subjective 82.7 (SD 11.8), Lysholm 87.6 (SD 8.1), Tegner 5.3 (SD 2.1), Cincinnati 88.7 (SD 14.8). The failure rate (i.e. persisting knee instability assessed clinically or by rolimeter) was 12.5%. At objective measurements, knee joints showed a firm endpoint in Lachman test, negative pivot shift phenomenon and a significant reduction in AP-laxity compared to pre-operative status by rolimeter testing (p = 0.002). Return to sport practice was achieved after mean 4.8 months (SD 4.1)., Conclusions: ACL stump trephination and concomitant intra-ligamentary application of ACP revealed promising results at mid-term follow-up to treat partial ACL lesions.

Background and Aims: Phragmites australis is a wetland grass with high genetic variability, augmented by its cosmopolitan distribution, clonal growth form and large variation in chromosome numbers. Different ploidy levels and ecotypes differ in morphology and ecophysiological traits, and may possess different levels of phenotypic variation. The aim of this study was to quantify the natural variation in ecophysiological characteristics of P. australis, and to explore whether differences in ecophysiological traits can be related to ploidy levels or to the geographic origin of the clones., Methodology: Fifteen clones of P. australis from Europe and Asia/Australia, representing five ploidy levels (4x, 6x, 8x, 10x and 12x), were grown in a common garden design for 119 days. Plant growth and light-saturated rate of photosynthesis (P(max)), stomatal conductance (g(s)), water use efficiency (WUE) and concentrations of photosynthetic pigments and mineral ions in the leaves were measured., Principal Results: The growth of the plants and most ecophysiological parameters differed significantly between clones. The mean maximum shoot height varied from 0.9 to 1.86 m, P(max) from 9.7 to 27 µmol m(-2) s(-1), g(s) from 0.22 to 1.41 mol m(-2) s(-1) and WUE from 13 to 47 µmol mol(-1). The concentrations of chlorophylls did not vary significantly between clones, but the chlorophyll a/b ratio and the concentrations of total carotenoids did. The observed differences were not explained either by the ploidy level per se or by the geographic origin or phylogenetic relationships of the clones., Conclusions: Phylogeographic relationships in P. australis on a global scale do not mirror the environment where the adaptations have evolved, and high phenotypic variation among and within clones complicates comparative studies. Future studies aimed at explaining differences in plant behaviour between P. australis populations should be careful in the selection of target genotypes and/or populations, and should avoid generalizing their findings beyond the genotypes and/or populations studied.

Bioremediation of perchlorate-contaminated groundwater can occur via bacterial reduction of perchlorate to chloride. Although perchlorate reduction has been demonstrated in bacterial pure cultures, little is known about the efficacy of using perchlorate-reducing bacteria as inoculants for bioremediation in the field. A pilot-scale, fixed-bed bioreactor containing plastic support medium was used to treat perchlorate-contaminated groundwater at a site in Southern California. The bioreactor was inoculated with a field-grown suspension of the perchlorate-respiring bacterium Dechlorosoma sp. strain KJ and fed groundwater containing indigenous bacteria and a carbon source amendment. Because the reactor was flushed weekly to remove accumulated biomass, only bacteria capable of growing in biofilms in the reactor were expected to survive. After 26 days of operation, perchlorate was not detected in bioreactor effluent. Perchlorate remained undetected by ion chromatography (detection limit 4 mug L(-1)) during 6 months of operation, after which the reactor was drained. Plastic medium was subsampled from top, middle, and bottom locations of the reactor for shipment on blue ice and storage at -80 degrees C prior to analysis. Microbial community DNA was extracted from successive washes of thawed biofilm material for PCR-based community profiling by 16S-23S ribosomal intergenic spacer analysis (RISA). No DNA sequences characteristic of strain KJ were recovered from any RISA bands. The most intense bands yielded DNA sequences with high similarities to Dechloromonas spp., a closely related but different genus of perchlorate-respiring bacteria. Additional sequences from RISA profiles indicated presence of representatives of the low G+C gram-positive bacteria and the Cytophaga-Flavobacterium-Bacteroides group. Confocal scanning laser microscopy and fluorescence in situ hybridization (FISH) were also used to examine biofilms using genus-specific 16S ribosomal RNA probes. FISH was more sensitive than RISA profiling in detecting possible survivors from the initial inoculum. FISH revealed that bacteria hybridizing to Dechlorosoma probes constituted <1% of all cells in the biofilms examined, except in the deepest portions where they represented 3-5%. Numbers of bacteria hybridizing to Dechloromonas probes decreased as biofilm depth increased, and they were most abundant at the biofilm surface (23% of all cells). These spatial distribution differences suggested persistence of low numbers of the inoculated strain Dechlorosoma sp. KJ in parts of the biofilm nearest to the plastic medium, concomitant with active colonization or growth by indigenous Dechloromonas spp. in the biofilm exterior. This study demonstrated the feasibility of post hoc analysis of frozen biofilms following completion of field remediation studies.

The abundance, distribution, and phylogenetic diversity of members of the Fe(III)-reducing family Geobacteraceae were studied along a gradient of metal contaminants in Lake Coeur d'Alene, Idaho. Partial 16S rRNA gene fragments were amplified by PCR using primers directed toward conserved regions of the gene within the family Geobacteraceae. Analysis of amplicons separated by denaturing gradient gel electrophoresis (DGGE) suggested within-site variation was as great as between-site variation. Amplicons were cloned and grouped by RFLP type and DGGE migration distance and representatives were sequenced. Grouping clones with 3% or less sequence dissimilarity, 15 distinct phylotypes were identified compared to 16 distinct DGGE bands. Only 1 phylotype was recovered from all sites. This clone, B14, is most closely related to Geobacter metallireducens and constituted a greater portion of the pristine community than of the contaminated communities. A second phylotype, Q2, predominated in the contaminated communities and was notably absent from the pristine libraries. Clone Q2 presents a high degree of sequence similarity to two Geobacter spp. previously isolated from this region of Lake Coeur d'Alene. Six phylotypes were unique to the contaminated sediments, whereas two were found only in the pristine sediments. Indices of diversity (Shannon and Simpson) were consistently higher when calculated with DGGE data than when clone library data were used. Most-probable-number PCR and real-time PCR suggested that the Geobacteraceae phylotypes were spread relatively evenly across all three sites along the gradient. Our data indicate that the Geobacteraceae are diverse and abundant in Lake Coeur d'Alene sediments, regardless of metals content. These results provide insight into the ability of dissimilatory Fe(III)-reducing bacteria to colonize habitats with elevated metal concentrations, and they have important implications for the management and remediation of metal-contaminated sites.

Anaerobic microbial oxidation of Fe(II) was only recently discovered and very little is known about this metabolism. We recently demonstrated that several dissimilatory perchlorate-reducing bacteria could utilize Fe(II) as an electron donor under anaerobic conditions. Here we report on a more in-depth analysis of Fe(II) oxidation by one of these organisms, Dechlorosoma suillum. Similarly to most known nitrate-dependent Fe(II) oxidizers, D. suillum did not grow heterotrophically or lithoautotrophically by anaerobic Fe(II) oxidation. In the absence of a suitable organic carbon source, cells rapidly lysed even though nitrate-dependent Fe(II) oxidation was still occurring. The coupling of Fe(II) oxidation to a particular electron acceptor was dependent on the growth conditions of cells of D. suillum. As such, anaerobically grown cultures of D. suillum did not mediate Fe(II) oxidation with oxygen as the electron acceptor, while conversely, aerobically grown cultures did not mediate Fe(II) oxidation with nitrate as the electron acceptor. Anaerobic washed cell suspensions of D. suillum rapidly produced an orange/brown precipitate which X-ray diffraction analysis identified as amorphous ferric oxyhydroxide or ferrihydrite. This is similar to all other identified nitrate-dependent Fe(II) oxidizers but is in contrast to what is observed for growth cultures of D. suillum, which produced a mixed-valence Fe(II)-Fe(III) precipitate known as green rust. D. suillum rapidly oxidized the Fe(II) content of natural sediments. Although the form of ferrous iron in these sediments is unknown, it is probably a component of an insoluble mineral, as previous studies indicated that soluble Fe(II) is a relatively minor form of the total Fe(II) content of anoxic environments. The results of this study further enhance our knowledge of a poorly understood form of microbial metabolism and indicate that anaerobic Fe(II) oxidation by D. suillum is significantly different from previously described forms of nitrate-dependent microbial Fe(II) oxidation.

Primer sets were designed to target specific 16S ribosomal DNA (rDNA) sequences of photosynthetic bacteria, including the green sulfur bacteria, the green nonsulfur bacteria, and the members of the Heliobacteriaceae (a gram-positive phylum). Due to the phylogenetic diversity of purple sulfur and purple nonsulfur phototrophs, the 16S rDNA gene was not an appropriate target for phylogenetic rDNA primers. Thus, a primer set was designed that targets the pufM gene, encoding the M subunit of the photosynthetic reaction center, which is universally distributed among purple phototrophic bacteria. The pufM primer set amplified DNAs not only from purple sulfur and purple nonsulfur phototrophs but also from Chloroflexus species, which also produce a reaction center like that of the purple bacteria. Although the purple bacterial reaction center structurally resembles green plant photosystem II, the pufM primers did not amplify cyanobacterial DNA, further indicating their specificity for purple anoxyphototrophs. This combination of phylogenetic- and photosynthesis-specific primers covers all groups of known anoxygenic phototrophs and as such shows promise as a molecular tool for the rapid assessment of natural samples in ecological studies of these organisms.

Benzene contamination is a significant problem. It is used in a wide range of manufacturing processes and is a primary component of petroleum-based fuels. Benzene is a hydrocarbon that is soluble, mobile, toxic and stable, especially in ground and surface waters. It is poorly biodegraded in the absence of oxygen. However, anaerobic benzene biodegradation has been documented under various conditions. Although benzene biomineralization has been demonstrated with nitrate, Fe(III), sulphate or CO2 as alternative electron acceptors, these studies were based on sediments or microbial enrichments. Until now there were no organisms in pure culture that degraded benzene anaerobically. Here we report two Dechloromonas strains, RCB and JJ, that can completely mineralize various mono-aromatic compounds including benzene to CO2 in the absence of O2 with nitrate as the electron acceptor. This is the first example, to our knowledge, of an organism of any type that can oxidize benzene anaerobically, and we demonstrate the potential applicability of these organisms to the treatment of contaminated environments.

Recent studies on the diversity and ubiquity of Fe(III)-reducing organisms in different environments led to the isolation and identification of four new dissimilatory Fe(III)-reducers (strains H-2T, 172T, TACP-2T and TACP-5). All four isolates are non-motile, Gram-negative, freshwater, mesophilic, strict anaerobes with morphology identical to that of Geobacter metallireducens strain GS-15T. Analysis of the 16S rRNA sequences indicated that the new isolates belong to the genus Geobacter, in the delta-Proteobacteria. Significant differences in phenotypic characteristics, DNA-DNA homology and G+C content indicated that the four isolates represent three new species of the genus. The names Geobacter hydrogenophilus sp. nov. (strain H-2T), Geobacter chapellei sp. nov. (strain 172T) and Geobacter grbiciae sp. nov. (strains TACP-2T and TACP-5) are proposed. Geobacter hydrogenophilus and Geobacter chapellei were isolated from a petroleum-contaminated aquifer and a pristine, deep, subsurface aquifer, respectively. Geobacter grbiciae was isolated from aquatic sediments. All of the isolates can obtain energy for growth by coupling the oxidation of acetate to the reduction of Fe(III). The four isolates also coupled Fe(III) reduction to the oxidation of other simple, volatile fatty acids. In addition, Geobacter hydrogenophilus and Geobacter grbiciae were able to oxidize aromatic compounds such as benzoate, whilst Geobacter grbiciae was also able to use the monoaromatic hydrocarbon toluene.

Previous studies on the ubiquity and diversity of microbial (per)chlorate reduction resulted in the isolation of 20 new strains of dissimilatory (per)chlorate-reducing bacteria. Phylogenetic analysis revealed that all of the isolates were members of the Proteobacteria with representatives in the alpha-, beta- and gamma-subclasses. The majority of the new isolates were located in the beta-subclass and were closely related to each other and to the phototrophic Rhodocyclus species. Here an in-depth analysis of these organisms which form two distinct monophyletic groups within the Rhodocyclus assemblage is presented. Two new genera, Dechloromonas and Dechlorosoma, are proposed for these beta-subclass lineages which represent the predominant (per)chlorate-reducing bacteria in the environment. The type species and strains for these new genera are Dechloromonas agitata strain CKBT and Dechlorosoma suillum strain PST, respectively.

From enrichment cultures established for purple nonsulfur bacteria using water and sediment samples from Lake Bogoria and Crater Lake, two soda lakes in the African Rift Valley, three strains of purple nonsulfur bacteria were isolated; strain LBB1 was studied in detail. Cells of strain LBB1 were motile and spherical to rod-shaped, suggesting a relationship to Rhodobacter or Rhodovulum species, and the organism was capable of both phototrophic and chemotrophic growth on a wide variety of organic compounds. Phototrophically grown cultures were yellow to yellow-brown in color and grew optimally at pH 9 (pH range 7.5-10) and 1% NaCl (range 0-10%). In physiological studies of strain LBB1, neither photoautotrophy (H2- or sulfide-dependent) nor nitrogen fixation was observed. Absorption spectra revealed that all three strains contained bacteriochlorophyll a and carotenoids of the spheroidene pathway and synthesized only a light-harvesting (LH) I-type photosynthetic antenna complex. Electron microscopy of cells of strain LBB1 revealed a vesicular intracytoplasmic membrane system, although only a few vesicles were observed per cell. The G+C content of strain LBB1 DNA was 59 mol%, significantly lower than that of known Rhodobacter and Rhodovulum species, and its phylogeny as determined by ribosomal RNA gene sequencing placed it within the Rhodobacter/Rhodovulum clade yet distinct from all described species of either of these genera. The unique assemblage of properties observed in strain LBB1 warrants its inclusion in a new genus of purple nonsulfur bacteria and the name Rhodobaca bogoriensis is proposed herein, the genus name reflecting morphological characteristics and the species epithet referring to the habitat.