Uncovering injuries in Brazilian elite women's football: A prospective cohort study.

OBJECTIVES: To elucidate the injury profile in Brazilian elite women's football. DESIGN: Prospective cohort study. METHODS: Time-loss injuries, along with match and training exposure, were monitored throughout a full season in four Brazilian elite clubs. RESULTS: Sixty-three out of 133 players (47 %) sustained 112 time-loss injuries along the season, leading to 0.8 injuries per player on average. The overall injury incidence rate was 5.0 injuries per 1000 h of exposure. Sudden onset injuries occurred at a rate of 4.2/1000 h of overall exposure, with rates of 15.9/1000 h during matches and 2.9/1000 h during training sessions. Forty-eight percent of the time-loss injuries were attributed to non-contact events. Gradual onset injuries accounted for 16 % of the injuries, resulting in a rate of 0.8/1000 h of overall exposure. The most affected locations were knee and thigh (29 % of all injuries for each), followed by ankle (17 %) and hip/groin (13 %). Muscle/tendon was the most affected tissue (47 % of all injuries), followed by ligament/joint capsule (33 %), bone (10 %), and cartilage/synovium/bursa (7 %). Ankle sprains, hamstring strains, and anterior cruciate ligament injuries accounted for over one-third of the injuries. Mild, moderate, and severe injuries account for 40 %, 43 %, and 17 % of cases, respectively. Overall, 18 % of cases were categorized as re-injuries, and 40 % of those occurred within 2 months of the index injury. CONCLUSIONS: This study provides the initial understanding into the injury profile of Brazilian elite women's football. This information should serve as a guiding resource for injury prevention programs.

Are Previous Joint Injuries Associated with Muscle Performance in Volleyball Athletes?

Objective The aim of the present study is to determine whether previous shoulder and knee injuries were associated with isokinetic fatigue index and agonist/antagonist ratio of shoulder internal/external rotators and knee flexors/extensors in male volleyball athletes. Methods The current study is a cross-sectional investigation of 49 male elite volleyball players competing at a high level in Brazil. Isokinetic fatigue index and agonist/antagonist profiles were assessed during the preseason. Additionally, in order to record previous injuries, the athletes answered a standardized questionnaire. We conducted a receiver operating characteristic (ROC) curve analysis to determine the association strength and the clinically relevant cut-off point for variables presenting statistical significance for the area under the curve (AUC) (α = 0.05). An independent t-test was used to compare isokinetic variables between athletes with and without previous injury (α = 0.05). Results The results of the ROC curve analysis indicated that hamstring fatigue index values at 300 o /s were associated with the presence of previous knee injury (area under the curve [AUC] = 73%, p = 0.004), and shoulder external rotators fatigue index values at 360°/s were not associated with the presence of previous shoulder injury (AUC = 68%, p = 0.053). Conclusions Elite volleyball athletes who reported previous knee injuries were prone to a higher fatigue index than those reporting no injuries. Knee flexor resistance training might be useful for those athletes who reported knee injuries in the previous season.

Are Previous Joint Injuries Associated with Muscle Performance in Volleyball Athletes? / Lesões articulares prévias são associadas ao desempenho muscular de jogadores de voleibol?

Abstract Objective The aim of the present study is to determine whether previous shoulder and knee injuries were associated with isokinetic fatigue index and agonist/antagonist ratio of shoulder internal/external rotators and knee flexors/extensors in male volleyball athletes. Methods The current study is a cross-sectional investigation of 49 male elite volleyball players competing at a high level in Brazil. Isokinetic fatigue index and agonist/antagonist profiles were assessed during the preseason. Additionally, in order to record previous injuries, the athletes answered a standardized questionnaire. We conducted a receiver operating characteristic (ROC) curve analysis to determine the association strength and the clinically relevant cut-off point for variables presenting statistical significance for the area under the curve (AUC) (α = 0.05). An independent t-test was used to compare isokinetic variables between athletes with and without previous injury (α = 0.05). Results The results of the ROC curve analysis indicated that hamstring fatigue index values at 300o/s were associated with the presence of previous knee injury (area under the curve [AUC] = 73%, p= 0.004), and shoulder external rotators fatigue index values at 360°/s were not associated with the presence of previous shoulder injury (AUC = 68%, p= 0.053). Conclusions Elite volleyball athletes who reported previous knee injuries were prone to a higher fatigue index than those reporting no injuries. Knee flexor resistance training might be useful for those athletes who reported knee injuries in the previous season.

Resumo Objetivo O objetivo deste estudo é determinar se lesões prévias de ombro e joelho estavam associadas ao índice de fadiga isocinética e razão agonista/antagonista dos rotadores internos/externos do ombro e flexores/extensores do joelho em jogadores de voleibol. Métodos Esta é uma investigação transversal com 49 jogadores de voleibol de elite que competem em alto nível no Brasil. O índice de fadiga isocinética e os perfis de agonistas/antagonistas foram avaliados durante a pré-temporada. Além disso, para registro de lesões anteriores, os atletas responderam a um questionário padronizado. Conduzimos uma análise da curva de característica de operação do receptor (receiver operating characteristic, ROC) para determinar a força de associação e o ponto de corte clinicamente relevante de variáveis com significância estatística na área sob a curva (AUC) (α = 0,05). Um teste t independente comparou as variáveis isocinéticas entre atletas com e sem lesão prévia (α = 0,05). Resultados Os resultados da análise da curva ROC indicam que os valores do índice de fadiga dos isquiotibiais a 300o/s foram associados à presença de lesão prévia no joelho (área soba a curva [AUC] = 73%, p= 0,004), enquanto os valores do índice de fadiga dos rotadores externos do ombro a 360°/s não foram associados à presença de lesão prévia no ombro (AUC = 68%, p= 0.053). Conclusões Atletas de voleibol de elite que relataram lesões anteriores no joelho estavam propensos a um índice de fadiga maior do que aqueles que não relataram lesões. O treinamento de resistência de flexores do joelho pode ser útil para atletas com relatos de lesões no joelho na temporada anterior.

Football-specific extension of the IOC consensus statement: methods for recording and reporting of epidemiological data on injury and illness in sport 2020.

Several sports have published consensus statements on methods and reporting of epidemiological studies concerning injuries and illnesses with football (soccer) producing one of the first guidelines. This football-specific consensus statement was published in 2006 and required an update to align with scientific developments in the field. The International Olympic Committee (IOC) recently released a sports-generic consensus statement outlining methods for recording and reporting epidemiological data on injury and illness in sport and encouraged the development of sport-specific extensions.The Fédération Internationale de Football Association Medical Scientific Advisory Board established a panel of 16 football medicine and/or science experts, two players and one coach. With a foundation in the IOC consensus statement, the panel performed literature reviews on each included subtopic and performed two rounds of voting prior to and during a 2-day consensus meeting. The panel agreed on 40 of 75 pre-meeting and 21 of 44 meeting voting statements, respectively. The methodology and definitions presented in this comprehensive football-specific extension should ensure more consistent study designs, data collection procedures and use of nomenclature in future epidemiological studies of football injuries and illnesses regardless of setting. It should facilitate comparisons across studies and pooling of data.

Ankle Sprain in Young Athletes: A 2-Year Retrospective Study at a Multisport Club.

Objective The present study aimed to analyze ankle sprains in young athletes of basketball, futsal, artistic gymnastics, trampoline, tennis, judo, and volleyball over 2 seasons. Methods Data of 529 athletes in the 1 st year and of 495 athletes in the 2 nd year of analysis were investigated from the injury record database of a sports club. The following data were considered: the demographic characteristics (age, body mass, height, and sex), the mechanism (contact or noncontact), the severity, the moment at which the injury occurred, and the recurrence. Also, the incidence rate, the injury risk of the first ankle sprain, and the incidence rate ratio between sports were calculated. Results The athletes sustained 124 ankle sprains in the 2 years of analysis. The majority occurred during training (76.6%) and lead to absence from sports practice (75.8%). The injury recurrence was low: 2 athletes (1.6%) had a recurrence in the same year and 5 (4.0%) in the following year. The incidence rate (0.79 to 12.81 per 1,000 hours) and the injury risk (1.14 to 19.44%) varied among sports. Volleyball, basketball, and futsal presented the highest injury rate incidence. Tennis, gymnastics, and trampoline showed the lowest injury rate incidence. Judo showed an incidence rate different from those of basketball and volleyball in the 1 st year and similar to those of other sports in the 2 nd year. Conclusion Ankle sprain greatly impacted sports practice and presented characteristics that differ among the investigated sports. These findings may contribute to developing preventive injury programs.

Ankle Sprain in Young Athletes: A 2-Year Retrospective Study at a Multisport Club / Entorse no tornozelo em jovens atletas: Um estudo retrospectivo de 2 anos em um clube multiesportivo

Abstract Objective The present study aimed to analyze ankle sprains in young athletes of basketball, futsal, artistic gymnastics, trampoline, tennis, judo, and volleyball over 2 seasons. Methods Data of 529 athletes in the 1st year and of 495 athletes in the 2nd year of analysis were investigated from the injury record database of a sports club. The following data were considered: the demographic characteristics (age, body mass, height, and sex), the mechanism (contact or noncontact), the severity, the moment at which the injury occurred, and the recurrence. Also, the incidence rate, the injury risk of the first ankle sprain, and the incidence rate ratio between sports were calculated. Results The athletes sustained 124 ankle sprains in the 2 years of analysis. The majority occurred during training (76.6%) and lead to absence from sports practice (75.8%). The injury recurrence was low: 2 athletes (1.6%) had a recurrence in the same year and 5 (4.0%) in the following year. The incidence rate (0.79 to 12.81 per 1,000 hours) and the injury risk (1.14 to 19.44%) varied among sports. Volleyball, basketball, and futsal presented the highest injury rate incidence. Tennis, gymnastics, and trampoline showed the lowest injury rate incidence. Judo showed an incidence rate different from those of basketball and volleyball in the 1st year and similar to those of other sports in the 2nd year. Conclusion Ankle sprain greatly impacted sports practice and presented characteristics that differ among the investigated sports. These findings may contribute to developing preventive injury programs.

Resumo Objetivo O presente estudo teve como objetivo analisar entorses no tornozelo em jovens atletas de basquete, futsal, ginástica artística, trampolim, tênis, judô e vôlei ao longo de duas temporadas. Métodos Foram investigados dados de 529 atletas no 1° ano e 495 atletas no 2° ano de análise a partir do banco de dados de registros de lesões de um clube esportivo. Foram considerados os seguintes dados: as características demográficas (idade, massa corporal, altura e sexo), o mecanismo (contato ou não contato), a severidade, o momento em que ocorreu a lesão e a recorrência. Além disso, foram calculadas a taxa de incidência, o risco de lesão da primeira entorse no tornozelo e a razão da taxa de incidência entre os esportes. Resultados Os atletas sofreram 124 entorses no tornozelo nos 2 anos de análise. A maioria ocorreu durante o treinamento (76,6%) e levou à interrupção da prática esportiva (75,8%). A recorrência da lesão foi baixa: 2 atletas (1,6%) tiveram recorrência no mesmo ano e 5 (4,0%) no ano seguinte. A taxa de incidência (0,79 a 12,81 por 1.000 horas) e o risco de lesão (1,14 a 19,44%) variaram entre os esportes. Vôlei, basquete e futsal apresentaram a maior incidência de lesões. Tênis, ginástica e trampolim apresentaram a menor incidência de lesões. O judô apresentou uma taxa de incidência diferente das do basquete e do vôlei no 1° ano e semelhante às dos outros esportes no 2° ano. Conclusão A entorse no tornozelo impactou muito a prática esportiva e apresentou características que diferem entre os esportes investigados. Esses achados podem contribuir para o desenvolvimento de programas de prevenção de lesões.

Interaction of hip and foot factors associated with anterior knee pain in mountain bikers.

OBJECTIVE: To investigate the association of interactions among trunk, hip, and foot/ankle musculoskeletal factors with the presence of anterior knee pain (AKP) in mountain bikers. DESIGN: Cross-sectional study. SETTING: Private clinical setting. PARTICIPANTS: Fifty professional and amateur cyclists, with and without AKP, were included. MAIN OUTCOME MEASURES: Bridge test with unilateral knee extension, hip stability isometric test (HipSIT), passive hip internal rotation (IR) range of motion (ROM), shank-forefoot alignment (SFA), and ankle dorsiflexion ROM were analyzed by classification and regression tree (CART) to identify interactions with AKP presence. A receiver-operating characteristic (ROC) curve verified accuracy of the model. To investigate strength of associations, prevalence ratios were calculated for each terminal node of the CART model. RESULTS: Interactions among passive hip IR ROM, HipSIT, ankle dorsiflexion ROM and SFA identified mountain bikers with and without AKP. The model achieved 76.9% sensitivity and 87.5% specificity. The area under the ROC curve was 0.86 (95% confidence interval: 0.75-0.97; standard error 0.05; p < 0.0001). CONCLUSION: Presence of AKP in mountain bike cyclists was associated with interactions among passive hip IR ROM, HipSIT and ankle dorsiflexion ROM captured by CART, indicating that the contribution of one factor depends on the presence of other factors.

Sports injury prevention programmes from the sports physical therapist's perspective: An international expert Delphi approach.

OBJECTIVE: To provide consensus on how to plan, organize and implement exercise-based injury prevention program (IPP) in sports. DESIGN: Delphi. SETTING: LimeSurvey platform. PARTICIPANTS: Experienced sports physical therapists from the International Federation of Sports Physical Therapy member countries. MAIN OUTCOME MEASURES: Factors related to sports IPP planning, organization and implementation. RESULTS: We included 305 participants from 32 countries. IPP planning should be based on an athlete's injury history, on pre-season screening results, and on injury rates (respectively, 98%, 92%, 89% agreement). In total 97% participants agreed that IPP organization should depend on the athlete's age, 93% on the competition level, and 93% on the availability of low-cost materials. It was agreed that IPP should mainly be implemented in warm-up sessions delivered by the head or strength/conditioning coach, with physical training sessions and individual physical therapy sessions (respectively, 94%, 92%, 90% agreement). CONCLUSION: Strong consensus was reached on (1) IPP based on the athlete's injury history, pre-season screening and evidence-based sports-specific injury rates; (2) IPP organization based on the athlete's age, competition level, and the availability of low-cost materials and (3) IPP implementation focussing on warm-up sessions implemented by the strength/conditioning coach, and/or individual prevention sessions by the physical therapist.

Hip external rotation isometric torque for soccer, basketball, and volleyball athletes: normative data and asymmetry index.

BACKGROUND: Deficits in strength of the hip external rotators (ER) affect trunk, hip, and knee movement patterns, potentially contributing to injury in athletes. OBJECTIVES: To provide normative data on isometric torque for hip ER in athletes of three distinct sports and to determine if isometric torque for the hip ER and torque asymmetry between legs differ among sports and between sexes. METHODS: Basketball, soccer, and volleyball athletes (n=451) were evaluated. Hip ER torque was quantified bilaterally with athletes in prone and 90° of knee flexion using a hand-held dynamometer. RESULTS: Data are expressed as mean and 95% confidence interval. Hip ER torque values in Nm/kg for the dominant and non-dominant limbs were, respectively, 0.46 (0.44, 0.48) and 0.42 (0.40, 0.44) for male soccer athletes; 0.35 (0.32, 0.37) and 0.27 (0.25, 0.29) for male basketball athletes; and 0.37 (0.34, 0.39) and 0.35 (0.32, 0.37) for male volleyball athletes. Hip ER torque in Nm/kg for the female volleyball athletes was 0.29 (0.26, 0.33) for the dominant and 0.29 (0.25, 0.32) for the non-dominant limb. The Limb Symmetry Index for male soccer, basketball, and volleyball players was, respectively, 94% (91, 97), 81% (75, 87), and 95% (91, 99). For female volleyball players the Limb Asymmetry Index was 102% (95, 108). Male volleyball athletes showed higher torque values than female volleyball athletes. CONCLUSIONS: This study reported normative values for hip ER isometric torque of youth athletes. Clinicians can use the reported data as reference to identify torque deficits in athletes of the three reported sports.

Preventive effect of tailored exercises on patellar tendinopathy in elite youth athletes: A cohort study.

OBJECTIVE: To investigate the effects of an intervention with tailored exercises on the incidence of patellar tendinopathy (PT) in elite youth jumping athletes. DESIGN: Prospective crossover cohort. SETTING: One sport club facility. PARTICIPANTS: 271 elite youth basketball and volleyball player were followed in the first year of the study (Observation year) and 270 athletes were followed in the second year (intervention year). MAIN OUTCOME MEASURE: Incidence rates of PT per 1,000h of exposure. Cox survival analysis was used to verify the effects of the intervention (exercises implemented according to the findings of a preseason assessment) on PT incidence. RESULTS: The exercise prevention program significantly reduced the number of cases of PT, with athletes submitted to the intervention showing 51% less risk of developing PT. The overall PT incidence in the Observation year (5.9 per 1,000h of exposure) was significantly higher than that in the intervention year (2.8 per 1,000h of exposure) (P = .037). Twenty-six athletes developed PT in the observation year, whereas 13 athletes developed PT in the intervention year. CONCLUSIONS: A tailored preventive program may be able to reduce the incidence of patellar tendinopathy, especially in male youth volleyball athletes. Randomized controlled trials are encouraged to confirm these findings.

Elevations in Liver Transaminases in COVID-19: (How) Are They Related?

Liver involvement in COVID-19 is not yet well-understood, but elevations in liver transaminases have been described to occur in 14-53% of the cases and are more frequently seen in severe disease. This cross-sectional study explored the relationship between the elevations in liver transaminases and inflammatory parameters in 209 adults with COVID-19. Demographic and clinical data, serum levels of inflammatory cytokines and liver aminotransferases were analyzed. Three groups were formed according to the liver transaminase abnormalities: (I) Normal transaminases, (II) Borderline transaminases elevation, and (III) Mild to severe transaminases elevation. Altered liver transaminases were directly related to disease severity, showing association with the NEWS2 score at admission and greater need for ICU or death. Moreover, higher levels of IL-2 and CRP were associated with borderline transaminases elevations, whereas higher levels of IL-10 and Neutrophil to Lymphocyte ratio were associated with mild to severe transaminases elevation. These results reinforce the importance of liver transaminases in patients with COVID-19 as a complementary marker for disease severity and also point to them as a parameter reflecting the continuous dynamics between viral infection and the immune response.

Concurrent Validation and Reference Values of Gluteus Medius Clinical Test.

CONTEXT: The hip abductor muscles, mainly the gluteus medius, are responsible for controlling hip adduction in a closed kinetic chain. Frontal plane knee alignment, assessed during functional activities such squatting, jumping and running, may overload joint structures, like the anterior cruciate ligament and patellofemoral joint. The hand-held dynamometer is reliable and effective for testing the muscular strength of the hip abductors. OBJECTIVES: 1. To assess the concurrent validity between the gluteus medius clinical test and a maximum isometric force test of the hip abductors using the hand-held dynamometer; (2) to determine the intra and inter-examiner reliability for the application of the gluteus medius clinical test; and (3) to describe reference values of gluteus medius clinical test on a population of youth athletes. DESIGN: Cross-sectional. METHODS: Thirty healthy individuals were recruited for validity and reliability testing. On the first day, participants performed the maximal isometric test of the hip abductors, measured via hand-held dynamometry. On the following week, the gluteus medius clinical test was performed. Intraclass correlation coefficients (ICC2,2) were computed for the reliability analysis, with a 95% confidence interval. To generate reference values, the gluteus medius clinical test was performed on 273 athletes. RESULTS: The results of this study indicated a weak positive correlation (r = 0.436, p = 0.001) between tests, which indicates that they examine different domains of gluteus medius muscle function, likely endurance and muscle strength. The magnitude of computed ICCs (>0.95) indicates excellent intra- and inter-examiner reliability. CONCLUSION: The findings of the current study indicate that the gluteus medius clinical test is reliable and examines a domain of muscular function not fully captured by HHD. The clinical test developed in this study is low-cost and can be included for gluteus medius assessment. LEVEL OF EVIDENCE: Level 3.

Clinical Risk Profile for a Second Anterior Cruciate Ligament Injury in Female Soccer Players After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: The risk of a second anterior cruciate ligament (ACL) injury when participating in pivoting sports after ACL reconstruction is high. Risk factors associated with a second ACL injury are complex. PURPOSE: To investigate the combinations of various clinical risk factors associated with second ACL injury in female soccer players with a primary unilateral ACL reconstruction, using Classification and Regression Tree (CART) analysis. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 117 active female soccer players (mean ± SD age, 20 ± 2 years) were included. Athletes were enrolled 19 ± 9 months after ACL reconstruction and were prospectively followed for 2 years. At baseline, all players underwent assessment of knee and ankle joint range of motion (ROM), participated in functional tests (postural control, hop performance, and movement asymmetries in the lower limbs and trunk), and answered questionnaires (patient-reported knee function, knee-related quality of life, psychological and personality factors). A clinical prediction model using CART was developed. RESULTS: A total of 28 players (24%) sustained a second ACL injury (21 ipsilateral and 7 contralateral ruptures) while playing soccer. CART analysis selected 9 of 19 independent variables associated with second ACL injury: the 5-jump test, knee collapse on the non-ACL reconstructed leg in a drop vertical jump, tuck jump, limb symmetry index on side hop and the single hop for distance, side difference in ankle dorsiflexion ROM, and scores for the questionnaires ACL-Return to Sport After Injury and the Swedish Universities Scales of Personality subscales of Stress Susceptibility and Adventure Seeking. The accuracy of the model was 89%, with 100% sensitivity and 76% specificity. CART analysis indicated that the interaction of longer jumps in the 5-jump test (>916 cm) with more side difference in ankle dorsiflexion ROM (>-2.5°) and more knee valgus collapse in the nonreconstructed knee (>-1.4 cm) (relative risk, 4.03; 95% CI, 2.21-7.36) best predicted an increased likelihood of a second ACL injury. CONCLUSION: The risk profiles selected by CART could accurately identify female soccer players at high risk for a second ACL injury. There was an interaction between functional performance, clinical assessment, and psychological factors, and it is reasonable to include these factors in return-to-sport decisions and in athlete screening after ACL injury.

Eccentric Strength Assessment of Hamstring Muscles with New Technologies: a Systematic Review of Current Methods and Clinical Implications.

BACKGROUND: Given the severe economic and performance implications of hamstring injuries, there are different attempts to identify their risk factors for subsequently developing injury prevention strategies to reduce the risk of these injuries. One of the strategies reported in the scientific literature is the application of interventions with eccentric exercises. To verify the effectiveness of these interventions, different eccentric strength measurements have been used with low-cost devices as alternatives to the widespread used isokinetic dynamometers and the technically limited handheld dynamometers. Therefore, the purpose of the present systematic review was to summarize the findings of the scientific literature related to the evaluation of eccentric strength of hamstring muscles with these new technologies. METHODS: Systematic searches through the PubMed, Scopus, and Web of Science databases, from inception up to April 2020, were conducted for peer reviewed articles written in English, reporting eccentric strength of hamstrings assessed by devices, different to isokinetic and handheld dynamometers, in athletes. RESULTS: Seventeen studies were finally included in the review with 4 different devices used and 18 parameters identified. The pooled sample consisted of 2893 participants (97% male and 3% female: 22 ± 4 years). The parameters most used were peak force (highest and average), peak torque (average and highest), and between-limb imbalance (left-to-right limb ratio). There is inconsistency regarding the association between eccentric hamstrings strength and both injury risk and athletic performance. There is no standardized definition or standardization of the calculation of the used parameters. CONCLUSIONS: The current evidence is insufficient to recommend a practical guide for sports professionals to use these new technologies in their daily routine, due to the need for standardized definitions and calculations. Furthermore, more studies with female athletes are warranted. Despite these limitations, the eccentric strength of hamstring muscles assessed by different devices may be recommended for monitoring the neuromuscular status of athletes.

Normative data for hip strength, flexibility and stiffness in male soccer athletes and effect of age and limb dominance.

OBJECTIVE: The objective was to establish normative data for hip strength, flexibility, and stiffness in male soccer athletes and to investigate the effect of age and limb dominance on these variables. DESIGN: Cross-sectional. SETTING: Soccer team physical therapy department. PARTICIPANTS: A total of 293 asymptomatic male soccer athletes were assessed. Elite youth players aged 15-17 years and professional adult players aged 18-29 years old. MAIN OUTCOME MEASURES: Rectus femoris, iliopsoas, hamstring muscle flexibility, passive hip stiffness, and isometric hip strength were measured using a goniometer, inclinometer, and handheld dynamometer, respectively. Descriptive and mixed analyses of variance were used as statistical procedures. RESULTS: The dominant limb had lower iliopsoas (P = 0.010) and rectus femoris (P = 0.003) flexibility and higher external rotators torque compared to the non-dominant limb (P = 0.006) in both age groups. In adult athletes, the dominant limb had lower hip stiffness than the non-dominant limb (P = 0.002). Adults had higher hip external rotator torque than younger athletes (P < 0.0001). No differences were observed for hamstrings flexibility and hip extensors torque. CONCLUSION: This study provided normative data of hip strength, flexibility, and stiffness for youth and adult male soccer athletes. In addition, there were no clinically relevant inter-limb differences.

Correlation between goniometric and photogrammetric assessment of shank-forefoot alignment in athletes.

BACKGROUND: The shank-forefoot alignment (SFA) measurement has been previously developed to enhance the applicability of foot alignment measurement in sports preseason assessment because it is reliable and less time consuming. The use of SFA measurements in the clinical context, usually done with photogrammetry, may be simplified by using the universal goniometer and no longer requiring the image processing step that takes additional time and equipment. OBJECTIVE: Investigate the correlation between the goniometric and photogrammetric assessment of shank-forefoot alignment in athletes. PARTICIPANTS: Thirty volleyball athletes were recruited during a preseason assessment. METHODS: SFA measurements were assessed with a universal goniometer and photogrammetry. For both assessments the participants were positioned in prone with the rearfoot facing up and the ankle actively maintained in 90° of dorsiflexion. The examiner did not have access to the SFA outcome values from both measurements. A second examiner did the bi-dimensional analysis with SIMI MOTION (photogrammetric measure) and read the goniometer measures during the other SFA assessment. Data normality was tested using Shapiro-Wilk test and Pearson was used to determine the correlation between both measurements. RESULTS: A reliability study determined the Intraclass Correlation Coefficient (ICC3,3) for intra-rater reliability of 0.93 for photogrammetry and of 0.81 for goniometry assessment. The correlation (p < 0.001) between these two measurements was 0.71, which indicates a moderate relationship. CONCLUSIONS: This study describes a reliable and practical measurement procedure for shank-forefoot alignment using the universal goniometer that can be easily applied in clinical context.

Sports Injury Forecasting and Complexity: A Synergetic Approach.

The understanding that sports injury is the result of the interaction among many factors and that specific profiles could increase the risk of the occurrence of a given injury was a significant step in establishing programs for injury prevention. However, injury forecasting is far from being attained. To be able to estimate future states of a complex system (forecasting), it is necessary to understand its nature and comply with the methods usually used to analyze such a system. In this sense, sports injury forecasting must implement the concepts and tools used to study the behavior of self-organizing systems, since it is by self-organizing that systems (i.e., athletes) evolve and adapt (or not) to a constantly changing environment. Instead of concentrating on the identification of factors related to the injury occurrence (i.e., risk factors), a complex systems approach looks for the high-order variables (order parameters) that describe the macroscopic dynamic behavior of the athlete. The time evolution of this order parameter informs on the state of the athlete and may warn about upcoming events, such as injury. In this article, we describe the fundamental concepts related to complexity based on physical principles of self-organization and the consequence of accepting sports injury as a complex phenomenon. In the end, we will present the four steps necessary to formulate a synergetics approach based on self-organization and phase transition to sports injuries. Future studies based on this experimental paradigm may help sports professionals to forecast sports injuries occurrence.

Statement on Methods in Sport Injury Research From the First METHODS MATTER Meeting, Copenhagen, 2019.

SYNOPSIS: High-quality sports injury research can facilitate sports injury prevention and treatment. There is scope to improve how our field applies best-practice methods-methods matter (greatly!). The first METHODS MATTER meeting, held in January 2019 in Copenhagen, Denmark, was the forum for an international group of researchers with expertise in research methods to discuss sports injury methods. We discussed important epidemiological and statistical topics within the field of sports injury research. With this opinion document, we provide the main take-home messages that emerged from the meeting. Meeting participants agreed that the definition of sport injury depends on the research question and context. It was considered essential to be explicit about the goal of the research effort and to use frameworks to illustrate the assumptions that underpin measurement and the analytical strategy. Complex systems were discussed to illustrate how potential risk factors can interact in a nonlinear way. This approach is often a useful alternative to identifying single risk factors. Investigating changes in exposure status over time is important when analyzing sport injury etiology, and analyzing recurrent injury, subsequent injury, or injury exacerbation remains challenging. The choice of statistical model should consider the research question, injury measure (eg, prevalence, incidence), type and granularity of injury data (categorical or continuous), and study design. Multidisciplinary collaboration will be a cornerstone for future high-quality sport injury research. Working outside professional silos in a diverse, multidisciplinary team benefits the research process, from the formulation of research questions and designs to the statistical analyses and dissemination of study results in implementation contexts. This article has been copublished in the British Journal of Sports Medicine and the Journal of Orthopaedic & Sports Physical Therapy. J Orthop Sports Phys Ther 2020;50(5):226-233. doi:10.2519/jospt.2020.9876.

Statement on methods in sport injury research from the 1st METHODS MATTER Meeting, Copenhagen, 2019.

High quality sports injury research can facilitate sports injury prevention and treatment. There is scope to improve how our field applies best practice methods-methods matter (greatly!). The 1st METHODS MATTER Meeting, held in January 2019 in Copenhagen, Denmark, was the forum for an international group of researchers with expertise in research methods to discuss sports injury methods. We discussed important epidemiological and statistical topics within the field of sports injury research. With this opinion document, we provide the main take-home messages that emerged from the meeting.

Lower limb kinematics and hip extensors strengths are associated with performance of runners at high risk of injury during the modified Star Excursion Balance Test.

BACKGROUND: Reduced trunk and lower limb movement and hip and trunk muscles weakness may compromise the athletes' performance on the modified Star Excursion Balance Test (mSEBT). OBJECTIVE: To investigate the relationship of trunk and lower limb kinematics and strength with the performance on the mSEBT of runners at high risk of injury. METHODS: Thirty-nine runners performed the mSEBT with the dominant limb as the support limb. An Inertial System was used to capture the trunk, hip, knee and ankle movement during the mSEBT. A handheld dynamometer was used to measure the strength of trunk extensors and lateral flexors muscles, and hip extensors, lateral rotators and abductors of the support limb. Multiple regressions were used to investigate if trunk and lower limbs kinematics and trunk and hip muscles strength are associated with performance during the mSEBT. RESULTS: Reduced hip flexion and greater knee flexion range of motion (ROM) were associated with anterior reach in the mSEBT (r2=0.45; p<.001), greater hip flexion ROM was associated with posteromedial reach (r2=0.15; p=.012) and greater knee flexion ROM was associated with posterolateral reach (r2=0.23; p<.001). Hip extensor strength was associated with posteromedial (r2=0.14; p=.017), posterolateral (r2=0.10; p=.038) and composite reaches (r2=0.16; p=.009). CONCLUSION: Hip and knee kinematics in the sagittal plane explained 15-45% of the runners' performance on the mSEBT and hip extensor strength explained 10-16% of the mSEBT performance. These findings provide useful information on the contribution of joints kinematics and strength when evaluating dynamic postural control in runners at high risk of injury.