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.

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.

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.

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.

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.

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.

Interventions used for Rehabilitation and Prevention of Patellar Tendinopathy in athletes: a survey of Brazilian Sports Physical Therapists.

OBJECTIVES: (1) To identify the type and frequency of interventions used by Brazilian physical therapists to treat and prevent the occurrence of patellar tendinopathy in athletes and the criteria used to return to sport; (2) to compare the interventions used to the grade of recommendation of current evidence. METHODS: Design: cross-sectional study. SETTING: online survey throughout sports physical therapy association. PARTICIPANTS: Physical therapists who were invited to complete a structured questionnaire. MAIN OUTCOME MEASURES: Interventions more frequently used for treating and preventing PT in athletes and the criteria used to define return to sport. RESULTS: One-hundred and twenty-one physical therapists participated in this study. Quadriceps eccentric strengthening (75.2%), education (61.2%) and lower limb joint/lumbo-pelvic stabilization/hamstrings stretching (59.5%) were more frequently cited for prevention purposes, while lower limb joint stabilization (81.8%), education (80.2%) and myofascial release (78.5%) were more frequently reported for treatment. The majority of the physical therapists based their decision of athlete discharge on a combination of pain intensity, function and functional test results (44.6%). CONCLUSION: There was inconsistency between interventions used in clinical practice and interventions recommended by the best available evidence.

Comparison of glenohumeral joint rotation range of motion in young athletes / Comparação da amplitude de movimento de rotação da articulação glenoumeral em atletas jovens / Comparación de la amplitud de movimiento de rotación de la articulación glenohumeral en atletas jóvenes

ABSTRACT Introduction: Overhead-throwing athletes undergo changes in shoulder range of motion (ROM) due to sports activities, such as excessive amplitude, lateral rotation (LR) increase and medial rotation (MR) restriction. Asymmetry greater than 20° may render athletes more prone to injuries. There are similarities among sports featuring overhead throwing due to the considerable amount of movements involving maximum lateral rotation. In these sports, medial rotation (MR) restriction, excess of lateral rotation (LR) and shoulder pain are common, particularly in overhead-throwing athletes. Objective: To assess shoulder MR and LR ROM in athletes participating in different sports, considering the influence of these variables on injuries and functional performance. Methods: The rotation ROM of the glenohumeral joint was assessed in 477 young athletes, who were categorized in three sports groups: swimming, overhead-throwing and non-overhead throwing, distributed by age group. Analyses of Variance (ANOVA) were performed to verify if there were differences in MR and LR between groups and paired Student t test was used to verify differences between sides (asymmetry). Results: Youngest athletes showed significant shorter LR than the oldest, in both sides. This study demonstrated that the right side has less MR and greater LR in all groups. Conclusion: The findings showed that overhead-throwing and swimming groups have similarities in shoulder rotation ROM. Level of evidence III; Diagnostic Studies - Investigating a Diagnostic Test.

RESUMO Introdução: Os atletas arremessadores sofrem adaptações na amplitude de movimento (ADM) do ombro, como amplitude excessiva, ganho de rotação lateral (RL) e restrição de rotação medial (RM) devido à prática esportiva. Uma assimetria maior que 20° pode tornar o atleta mais suscetível a lesões. Existem semelhanças entre os esportes que utilizam arremesso devido à ampla quantidade de movimentos em rotação lateral máxima. Nesses esportes, a restrição de rotação medial (RM), o excesso de rotação lateral (RL) e as dores no ombro são frequentes, principalmente, em atletas que são expostos aos arremessos. Objetivo: Avaliar a ADM de RM e RL do ombro de atletas de diferente modalidades esportivas considerando sua influência nas lesões e no desempenho funcional. Métodos: Avaliou-se a ADM de rotação da articulação glenoumeral em 477 atletas jovens. Os atletas foram categorizados em três grupos de esportes: natação; arremesso e não-arremesso, distribuídos em relação à faixa etária. As Análises de Variância (ANOVA) foram realizadas para verificar diferenças nas RM e RL entre os grupos e o Teste t Student pareado para verificar diferenças entre os lados (assimetria). Resultados: Os atletas mais novos apresentaram média de RL significativamente menor em relação aos mais velhos, em ambos os lados. O presente estudo demonstrou que o lado direito possui menor RM e maior RL em todos os grupos. Conclusão: Os achados desse estudo comprovaram que os grupos de arremesso e natação têm características semelhantes quanto à ADM de rotação do ombro. Nível de evidência III; Estudos diagnósticos - Investigação de um exame para diagnóstico.

RESUMEN Introducción: Los atletas lanzadores sufren adaptaciones en la amplitud de movimiento (ADM) del hombro, como amplitud excesiva, aumento de rotación lateral (RL) y restricción de rotación medial (RM), debido a la práctica deportiva. Una asimetría mayor que 20° puede hacer que el atleta sea más susceptible a las lesiones. Hay similitudes entre los deportes que utilizan el lanzamiento debido a la gran cantidad de movimientos en rotación lateral máxima. En estos deportes, la restricción de rotación medial (RM), exceso de rotación lateral (RL) y dolores en el hombro son frecuentes, principalmente en atletas que están expuestos a los lanzamientos. Objetivo: Evaluar la ADM de RM y RL del hombro de atletas de diferentes modalidades deportivas teniendo en vista su influencia en las lesiones y en el desempeño funcional. Métodos: Se evaluó la ADM de rotación de la articulación glenohumeral en 477 atletas jóvenes. Los atletas se clasificaron en tres grupos de deportes: natación; lanzadores y no Lanzadores, distribuidos con relación al grupo de edad. Los análisis de varianza (ANOVA) se realizaron para verificar diferencias en las RM y RL entre los grupos y el test t Student pareado para verificar diferencias entre los lados (asimetría). Resultados: Los atletas más jóvenes presentaron un promedio de RL significativamente menor con relación a los más viejos, en ambos lados. Este estudio demostró que el lado derecho posee menor RM y mayor RL en todos los grupos. Conclusión: Los hallazgos de este estudio comprobaron que los grupos de lanzadores y natación tienen características similares cuanto a la ADM de rotación del hombro. Nivel de evidencia III; Estudios de diagnósticos - Investigación de un examen para diagnóstico.

The Accuracy of the VISA-P Questionnaire, Single-Leg Decline Squat, and Tendon Pain History to Identify Patellar Tendon Abnormalities in Adult Athletes.

Study Design Cross-sectional clinical assessment. Background Patellar tendinopathy is not always accompanied by patellar tendon abnormalities (PTAs). Thus, clinical screening tools to help identify patients with patellar tendon pain who have PTAs could enhance clinical decision making and patient prognosis. Objectives To test the diagnostic accuracy of the Victorian Institute of Sport Assessment-Patella (VISA-P) questionnaire, a single-leg decline squat (SLDS), tendon pain history, age, and years of sports participation to identify athletes with symptomatic patellar tendons who have PTAs confirmed on imaging. Methods Data provided by ultrasound examination, the VISA-P questionnaire, the SLDS, tendon pain history, age, and years of sport participation were collected in 43 athletes. A classification and regression tree (CART) model was developed to verify variables associated with PTA occurrence. Likelihood ratios (LRs) were computed for positive and negative tests. Results The SLDS, VISA-P questionnaire, and tendon pain history were associated with PTA occurrence. Athletes with negative results on all 3 tests (CART model) had a lower likelihood of having PTAs (negative LR = 0.3; 95% confidence interval [CI]: 0.2, 0.5). The isolated use of the SLDS or tendon pain history (positive LR = 4.2; 95% CI: 2.3, 7.14 and 4.5; 95% CI: 1.8, 11.1, respectively) had similar influence on probability of PTA presence compared to the CART model (positive LR = 4.1; 95% CI: 2.5, 6.3). Conclusion Although the objective was to investigate a clinical test to identify PTAs, the combined use of the tests had greater accuracy to identify individuals without PTAs. Level of Evidence Diagnosis, level 3b. J Orthop Sports Phys Ther 2016;46(8):673-680. Epub 3 Jul 2016. doi:10.2519/jospt.2016.6192.

Reference values of hip abductor torque among youth athletes: Influence of age, sex and sports.

OBJECTIVE: (1) To determine the reference values of hip abductor torque in youth athletes; (2) To investigate the influence of sex, age and sports on hip abductors torque. DESIGN: Cross-sectional. SETTING: Sports clubs. SUBJECTS: 301 volleyball, basketball and futsal athletes between 10 and 19 years of age. MAIN OUTCOME MEASURES: Mean value of three maximal isometric hip abductor torques, evaluated using a hand-held dynamometer. RESULTS: The mean values of maximal isometric hip abductor torque ranged from 1.03 to 1.50 Nm/kg. The dominant hip abductor torque values were greater in 15-19 years old (1.41 ± 0.27 Nm/kg) than in 10-14 years old (1.12 ± 0.31 Nm/kg). In addition, the hip abductor torque values were smaller in basketball players (1.15 ± 0.31 Nm/kg) than futsal (1.34 ± 0.37 Nm/kg) and volleyball players (1.28 ± 0.25 Nm/kg). The comparison of hip abductor torque between futsal and volleyball players revealed no difference. The hip abductor torque values were greater in male volleyball athletes (1.28 ± 0.25 Nm/kg) than female volleyball athletes (1.13 ± 0.22 Nm/kg). CONCLUSION: This study established reference values for maximal isometric hip abductor torque in youth volleyball, basketball and futsal athletes. In addition, the results demonstrated that sex, age and sports influenced hip abductor torque.

Normative data of frontal plane patellar alignment in athletes.

OBJECTIVE: The objective of this study was to provide normative data of frontal plane patellar alignment according to McConnell and Arno angles, verify the association between theses angles and identify the presence of patellar rotation in different sports. DESIGN: Cross-sectional. PARTICIPANTS: Nine participants (18 knees) were assessed in a preliminary study to verify the intra and inter-examiner reliabilities of the patellar alignment measures. In the main study, 230 volleyball, basketball, gymnastics and soccer athletes (460 knees) were evaluated in order to obtain normative data of patellar alignment. MAIN OUTCOME MEASURES: Frontal plane patellar alignment (McConnell and Arno angles) measured in standing position by means of photogrammetry. RESULTS: The standardized method demonstrated intra and inter-examiner reliability coefficients varying from .85 to .98. The mean McConnell and Arno angles were 2.05° (±5.9) and 2.89° (±7.57), respectively. A low association was observed (r = .189, p < .0001) between these angles. There was a difference in distribution of medial and lateral rotations, according to the McConnell angle, between different sports (p < .014). CONCLUSIONS: The proposed procedure for measuring patellar alignment according to McConnell and Arno angles proved to be highly reliable. This made possible the establishment of normative data in a large sample of healthy athletes.

A quick and reliable procedure for assessing foot alignment in athletes.

BACKGROUND: Quick procedures with proper psychometric properties that can capture the combined alignment of the foot-ankle complex in a position that may be more representative of the status of the lower limb during ground contact are essential for assessing a large group of athletes. METHODS: The assessed lower limb was positioned with the calcaneus surface facing upward in a way that all of the marks could be seen at the center of the camera display. After guaranteeing maintenance of the foot at 90° of dorsiflexion actively sustained by the athlete, the examiner took the picture of the foot-ankle alignment. RESULTS: Intraclass correlation coefficients ranging from 0.82 to 0.93 demonstrated excellent intratester and intertester reliability for the proposed measurements of forefoot, rearfoot, and shank-forefoot alignments. The intraclass correlation coefficient between the shank-forefoot measures and the sum of the rearfoot and forefoot measures was 0.98, suggesting that the shank-forefoot alignment measures can represent the combined rearfoot and forefoot alignments. CONCLUSIONS: This study describes a reliable and practical measurement procedure for rearfoot, forefoot, and shank-forefoot alignments that can be applied to clinical and research situations as a screening procedure for risk factors for lower-limb injuries in athletes.

Muscle co-contraction after anterior cruciate ligament reconstruction: Influence of functional level.

BACKGROUND: ACL reconstruction is recommended to improve function in subjects with ligament injuries. However, after surgery, some individuals are not able to return to their pre-injury functional level. The mechanisms related to this incapacity are not well understood. STUDY DESIGN: Cross-sectional study. METHODS: Co-contraction levels were assessed in individuals who returned to their pre-injury functional level and in 10 individuals who were not able to return to full activity after unilateral ACL reconstruction. Electromyography of the vastus lateralis and biceps femoris muscles before and after sudden perturbations applied during the stance phase of walking was used to calculate co-contraction. RESULTS: The involved limb had lower co-contraction pre-perturbation than the non-involved limb in both groups (p=0.049). The co-contraction level post-perturbation was significantly higher in the limited return group than in the full return group (p=0.03). CONCLUSION: Decreased co-contraction in the involved limb before perturbation may be caused by sensorial changes resulting from surgery or injury. Increased co-contraction levels observed in the limited return group after perturbation may be a compensatory mechanism to make up for possible decreased intrinsic stability of the knee joint. CLINICAL RELEVANCE: Increased co-contraction after perturbation does not contribute to knee stability.

Avaliação muscular isocinética da articulação do ombro em atletas da Seleção Brasileira de voleibol sub-19 e sub-21 masculino / Isokinetic muscular assessment of the shoulder joint in athletes from the male under-19 and under-21 Brazilian volleyball teams

INTRODUÇÃO E OBJETIVO: A musculatura do complexo do ombro possui um papel importante na produção de força e potência articular no voleibol, permitindo a realização do gesto esportivo de maneira coordenada. A documentação objetiva produzida pela avaliação isocinética auxilia no diagnóstico e na prevenção de lesões do complexo do ombro, além de ser uma ferramenta útil no prognóstico do retorno rápido e seguro para a prática esportiva do atleta lesionado. O objetivo deste estudo foi avaliar o desempenho muscular isocinético dos músculos rotadores laterais e mediais da articulação glenoumeral em atletas de voleibol da Seleção Brasileira Masculina sub-19 e sub-21. MÉTODOS: O protocolo realizado durante o teste foi de cinco repetições máximas de rotação lateral e medial de ombro no modo concêntrico-concêntrico na velocidade de 60º/s e 30 repetições na velocidade de 360º/s. Análise de variância (ANOVA) mista foi utilizada para avaliar as variáveis dependentes: trabalho máximo e torque máximo normalizados pela massa corporal dos músculos rotadores laterais e mediais do ombro, razão agonista/antagonista nas duas velocidades e índice de fadiga muscular. RESULTADOS: A análise dos dados demonstrou haver um desequilíbrio entre os rotadores laterais e mediais (razão agonista/antagonista) da articulação do ombro em atletas brasileiros de voleibol da categoria sub-21, revelando menor força relativa dos rotadores laterais. CONCLUSÃO: Foi possível identificar alterações em atletas de voleibol que, associadas a demandas específicas do esporte, podem levar à sintomatologia no complexo do ombro e/ou queda da performance.

INTRODUCTION AND PURPOSE: The shoulder complex muscles play an important role in force, power and endurance production in volleyball, allowing the accomplishment of movement in a coordinated manner. The objective written account produced by isokinetic evaluations assists in the diagnosis and prevention of shoulder complex injuries. In addition, it is a useful tool in promoting safe and fast return of the injured athlete to sports practice. The purpose of this study was to analyze the isokinetic muscle performance of the lateral and medial rotators of the glenohumeral joint in Brazilian male volleyball teams (under-19 and under-21). METHODS: The protocol used during the test included five maximum repetitions of shoulder lateral and medial rotation in concentric-concentric mode at 60º/s and 30 repetitions at 360º/s. Analysis of variance was used to evaluate the dependent variables: maximum work and maximum torque of shoulder lateral and medial rotators normalized by body mass, antagonist/agonist ratio at the two speeds and muscular fatigue index. RESULTS: Data analysis demonstrated an imbalance between the shoulder lateral and medial rotators (antagonist/agonist ratio) in the under-21 category of the Brazilian volleyball athletes, demonstrating relative weakness of the lateral rotators. CONCLUSION: It was possible to identify changes in volleyball players, which added to specific demands of the sport, can lead to symptoms in the shoulder complex and / or decrease of performance.

Análise do nível de frouxidão ligamentar e do desempenho funcional em indivíduos submetidos à reconstrução do LCA com o uso do terço central do ligamento patelar / An analysis of the ligament laxity level and functional perfomance in subjects submitted to ACL reconstruction with central third patellar ligament

Objetivo:Avaliar a existência da associação entre a frouxidão ligamentar e o desempenho funcional de indivíduos submetidos à reconstrução do ligamento cruzado anterior, com o uso do terço central do ligamento patelar. Métodos: Foram avaliados 86 indivíduos (seis do sexo feminino e 80 do masculino), submetidos à reconstrução do LCA, com um mínimo de um ano de cirurgia, por meio do artrômetro KT-lOOO e pela escala funcional Cincinnati Knee Rating System, para mensurar a frouxidão ligamentar residual e o nível funcional, respectivamente. A associação entre as duas variáveis foi analisada por meio da regressão simples. Resultados: Não houve associação entre a frouxidão ligamentar e o nível funcional (r = 0,034; R2 = 0,001; p =0,755). Conclusão: Os resultados do estudo possibilitam afirmar que o desempenho funcional dos indivíduos avaliados, submetidos à reconstrução, não pode ser explicado pela frouxidão ligamentar residual por eles apresentada