Does a SLAP lesion affect shoulder muscle recruitment as measured by EMG activity during a rugby tackle?

Background: The study objective was to assess the influence of a SLAP lesion on onset of EMG activity in shoulder muscles during a front on rugby football tackle within professional rugby players. Methods: Mixed cross-sectional study evaluating between and within group differences in EMG onset times. Testing was carried out within the physiotherapy department of a university sports medicine clinic. The test group consisted of 7 players with clinically diagnosed SLAP lesions, later verified on arthroscopy. The reference group consisted of 15 uninjured and full time professional rugby players from within the same playing squad. Controlled tackles were performed against a tackle dummy. Onset of EMG activity was assessed from surface EMG of Pectorialis Major, Biceps Brachii, Latissimus Dorsi, Serratus Anterior and Infraspinatus muscles relative to time of impact. Analysis of differences in activation timing between muscles and limbs (injured versus non-injured side and non injured side versus matched reference group). Results: Serratus Anterior was activated prior to all other muscles in all (P = 0.001-0.03) subjects. In the SLAP injured shoulder Biceps was activated later than in the non-injured side. Onset times of all muscles of the noninjured shoulder in the injured player were consistently earlier compared with the reference group. Whereas, within the injured shoulder, all muscle activation timings were later than in the reference group. Conclusions: This study shows that in shoulders with a SLAP lesion there is a trend towards delay in activation time of Biceps and other muscles with the exception of an associated earlier onset of activation of Serratus anterior, possibly due to a coping strategy to protect glenohumeral stability and thoraco-scapular stability. This trend was not statistically significant in all cases

The Value of Preseason Screening for Injury Prediction: The Development and Internal Validation of a Multivariable Prognostic Model to Predict Indirect Muscle Injury Risk in Elite Football (Soccer) Players

© 2020, The Author(s). Background: In elite football (soccer), periodic health examination (PHE) could provide prognostic factors to predict injury risk. Objective: To develop and internally validate a prognostic model to predict individualised indirect (non-contact) muscle injury (IMI) risk during a season in elite footballers, only using PHE-derived candidate prognostic factors. Methods: Routinely collected preseason PHE and injury data were used from 152 players over 5 seasons (1st July 2013 to 19th May 2018). Ten candidate prognostic factors (12 parameters) were included in model development. Multiple imputation was used to handle missing values. The outcome was any time-loss, index indirect muscle injury (I-IMI) affecting the lower extremity. A full logistic regression model was fitted, and a parsimonious model developed using backward-selection to remove factors that exceeded a threshold that was equivalent to Akaike’s Information Criterion (alpha 0.157). Predictive performance was assessed through calibration, discrimination and decision-curve analysis, averaged across all imputed datasets. The model was internally validated using bootstrapping and adjusted for overfitting. Results: During 317 participant-seasons, 138 I-IMIs were recorded. The parsimonious model included only age and frequency of previous IMIs; apparent calibration was perfect, but discrimination was modest (C-index = 0.641, 95% confidence interval (CI) = 0.580 to 0.703), with clinical utility evident between risk thresholds of 37–71%. After validation and overfitting adjustment, performance deteriorated (C-index = 0.589 (95% CI = 0.528 to 0.651); calibration-in-the-large = − 0.009 (95% CI = − 0.239 to 0.239); calibration slope = 0.718 (95% CI = 0.275 to 1.161)). Conclusion: The selected PHE data were insufficient prognostic factors from which to develop a useful model for predicting IMI risk in elite footballers. Further research should prioritise identifying novel prognostic factors to improve future risk prediction models in this field. Trial registration: NCT03782389

Chromosome conformation signatures define predictive markers of inadequate response to methotrexate in early rheumatoid arthritis

The authors would like to thank members of OBD Reference Facility Benjamin Foulkes, Chloe Bird, Emily Corfeld and Matthew Salter for expedient processing of clinical samples on the EpiSwitch™ platform and Magdalena Jeznach and Willem Westra for help with preparation of the manuscript. The study employed samples from the SERA Biobank used with permission and approval of the SERA Approval Group. We gratefully acknowledge the invaluable contribution of the clinicians and operating team in SERA. We would also like to thank Prof. Raju Kucherlapati (Harvard Medical School), and Prof. Jane Mellor (Oxford Univ.), Prof. John O’Shea (National Institute of Health) and Prof. John Isaacs (New Castle Univ.) for their independent and critical review of our study. A list of Scottish Early Rheumatoid Arthritis (SERA) inception cohort investigators is provided in Additional fle 1: Additional Note. Funding This work was funded by Oxford BioDynamics.Peer reviewedPublisher PD

Pronação excessiva e varismos de pé e perna: relação com o desenvolvimento de patologias músculo-esqueléticas - revisão de literatura

A literatura propõe mecanismos biomecânicos que relacionam a pronação subtalar excessiva ao desenvolvimento de diversas patologias músculo-esqueléticas. A presença dos desalinhamentos anatômicos antepé varo, retropé varo e tíbia vara pode levar à ocorrência da pronação subtalar excessiva. Entretanto, não existe um consenso sobre a contribuição do padrão de movimento e da presença desses desalinhamentos para o desenvolvimento de patologias. O objetivo deste estudo foi realizar uma revisão da literatura para investigar a influência de varismos aumentados de antepé, retropé e tíbia e da pronação subtalar excessiva no surgimento de patologias músculo-esqueléticas. Foi realizada uma pesquisa bibliográfica sistematizada nas bases Medline, ISI - Web of Science, Lilacs e Scielo, tendo sido selecionados 13 estudos analíticos. Do total de 13 estudos, 10 encontraram associação de patologias no membro inferior com um ou mais dos desalinhamentos anatômicos analisados ou com um ou mais parâmetros cinemáticos relacionadas à pronação subtalar excessiva. A análise dos estudos sugere que a pronação subtalar excessiva e/ou a presença de desalinhamentos que podem levar a esse padrão de movimento são possíveis fatores de risco para o desenvolvimento de patologias músculo-esqueléticas no membro inferior.The literature proposes biomechanical mechanisms that link excessive subtalar joint pronation to the development of several musculoskeletal pathologies. The presence of forefoot varus, rearfoot varus and tibiofibular varum can lead to the occurrence of excessive subtalar pronation. However, there is no consensus about the contribution of the movement pattern and/or the presence of these anatomical misalignments to the development of pathologies. The aim of the present study was to conduct a literature review in order to investigate the influence of increased varus alignment of forefoot, rearfoot and shank and of excessive subtalar pronation on the development of musculoskeletal pathologies. A systematic literature search was performed in the databases Medline, ISI - Web of Science, Lilacs and Scielo, and 13 analytic studies were selected. Ten studies found significant associations of lower-limb musculoskeletal pathologies with one or more of the anatomical misalignments analyzed or with one or more kinematic parameters related to excessive subtalar pronation. The analysis of the studies suggests that excessive pronation and/or the presence of these anatomical misalagniments should be regarded as possible risk factors for the development of musculoskeletal pathologies in the lower limb