Behavior of human gastrocnemius muscle fascicles during ramped submaximal isometric contractions.

Precise estimates of muscle architecture are necessary to understand and model muscle mechanics. The primary aim of this study was to estimate continuous changes in fascicle length and pennation angle in human gastrocnemius muscles during ramped plantar flexor contractions at two ankle angles. The secondary aim was to determine whether these changes differ between proximal and distal fascicles. Fifteen healthy subjects performed ramped contractions (0-25% MVC) as ultrasound images were recorded from the medial (MG, eight sites) and lateral (LG, six sites) gastrocnemius muscle with the ankle at 90° and 120° (larger angles correspond to shorter muscle lengths). In all subjects, fascicles progressively shortened with increasing torque. MG fascicles shortened 5.8 mm (11.1%) at 90° and 4.5 mm (12.1%) at 120°, whereas LG muscle fascicles shortened 5.1 mm (8.8%) at both ankle angles. MG pennation angle increased 1.4° at 90° and 4.9° at 120°, and LG pennation angle decreased 0.3° at 90° and increased 2.6° at 120°. Muscle architecture changes were similar in proximal and distal fascicles at both ankle angles. This is the first study to describe continuous changes in fascicle length and pennation angle in the human gastrocnemius muscle during ramped isometric contractions. Very similar changes occurred in proximal and distal muscle regions. These findings are relevant to studies modeling active muscle mechanics

Corticospinal excitability changes following blood flow restriction training of the tibialis anterior: a preliminary study

© 2017 The Authors Aim To examine the neural excitability of projections to the tibialis anterior (TA) following blood flow restriction training (BFRT). This is the first study to examine the TA following BFRT. Methods Ten subjects performed each experiment. Experiment one consisted of BFRT at 130 mmHg (BFRT-low). Experiment two consisted of BFRT at 200 mmHg (BFRT-high), training (TR-only) and blood flow restriction at 200 mmHg (BFR-only) performed on separate days. Blood flow restriction was applied to the thigh and training consisted of rapid dorsiflexion contractions against gravity every 10 s for 15-min. The motor evoked potential (MEP) peak-to-peak amplitudes were recorded pre-intervention and 1-, 10-, 20- and 30-min post-intervention and expressed relative to the maximal peak-to-peak M-wave at each time-point. Results Experiment one revealed no difference in MEP amplitudes for BFRT-low over time (P = 0.09). Experiment two revealed a significant effect of time (P < 0.001), with 1-min post-intervention MEP amplitudes significantly facilitated compared to pre-intervention, but no effect of intervention (P = 0.79) or intervention*time interaction (P = 0.25). Post-hoc power calculations were performed for the intervention*time interaction. Discussion and conclusions Corticospinal excitability of projections to the TA did not change following BFRT-low and corticospinal excitability changes between BFRT-high, BFR-only and TR-only interventions were not different over time. In experiment two, there was a significant main effect of time 1-min post-intervention which was mainly due to the BFRT-high intervention. Post-hoc power calculations revealed that 15 subjects were required for a significant interaction effect 80% of the time however, as the changes in corticospinal excitability were not prolonged, a new dataset of ≥ 15 subjects was not acquired

Between session reliability of heel-to-toe progression measurements in the stance phase of gait

© 2018 Ade et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The objective of the current study was to determine the test-retest reliability of heel-to-toe progression measures in the stance phase of gait using intraclass correlation coefficient (ICC) analysis. It has been proposed that heel-to-toe progression could be used as a functional measure of ankle muscle contracture/weakness in clinical populations. This was the first study to investigate the test-retest reliability of this measure. Eighteen healthy subjects walked over the GAITRite® mat three times at a comfortable speed on two sessions (≥ 48 hours apart). The reliability of the heel-to-toe progression measures; heel-contact time, mid-stance time and propulsive time were assessed. Also assessed were basic temporal-spatial parameters; velocity, cadence, stride length, step length, stride width, single and double leg support time. Reliability was determined using the ICC(3,1) model and, fixed and proportional biases, and measures of variability were assessed. Basic gait temporal-spatial parameters were not different between sessions (p > 0.05) and had excellent reliability (ICC(3,1) range: 0.871–0.953) indicating that subjects walked similarly between sessions. Measurement of heel-to-toe progression variables were not different between sessions (p > 0.05) and had excellent reliability (ICC(3,1) range: 0.845–0.926). However, these were less precise and more variable than the measurement of standard temporal-spatial gait variables. As the current study was performed on healthy populations, it represents the ‘best case’ scenario. The increased variability and reduced precision of heel-to-toe progression measurements should be considered if being used in clinical populations

Externally validated model predicting gait independence after stroke showed fair performance and improved after updating

ObjectiveTo externally validate recent prognostic models that predict independent gait following stroke.Study design and settingA systematic search identified recent models (ResultsThree prognostic models met our criteria, all with high Risk of Bias. Validation data was only available for the Australian model. This model used National Institute of Health Stroke Scale (NIHSS) and age to predict independent gait, using Motor Assessment Scale (MAS) walking item. For validation, Scandinavian Stroke Scale (SSS) was a proxy for NIHSS, and Functional Independence Measure (FIM) locomotion item was a proxy for MAS. The Area Under the Curve was 0.77 (0.74-0.80) and had good calibration in the validation dataset. Adjustment of the intercept and regression coefficients slightly improved discrimination. By adding paretic leg strength, the model further improved (AUC 0.82).ConclusionExternal validation of the Australian model with proxies showed fair discrimination and good calibration. Updating the model by adding paretic leg strength further improved model performance

Cohort profile: Design and implementation of the Danish Physiotherapy Research Database for patients receiving primary care with chronic disease

PurposeFree of charge physiotherapy (FCP) is free physiotherapy provided by the Danish government for patients with a range of chronic diseases. To date, the population has not been described in depth making evaluation and decision making difficult. The purpose of this study was to (1) describe the development and the content of a novel clinical physiotherapy database for FCP (PhysDB-FCP) and (2) present the cohort profile based on the data collected.ParticipantsNinety-nine clinics (17 460 FCP patients) were invited to participate in the development process from 2018 to 2019. Eleven clinics consented (2780 FCP patients) and 534 patients performed the physiotherapy assessment using the PhysDB-FCP tool, with 393/534 completing the patient survey.Findings to dateThe content of the PhysDB-FCP was developed through an iterative process involving consensus between clinical and research workgroups. Prior to using the tool all consenting sites received training to use/administer the tool. All data were collected/stored using the PhysDB-FCP. Items finally chosen for the PhysDB-FCP included demographic information, questions about health status and daily functioning, functional tests, treatment plan and validated questionnaires. The initial patient cohort composed of 63.4% women with main diagnoses of multiple sclerosis (22.7%) and Parkinson’s disease (17.0%). The ability to perform personal/instrumental activities of daily living and functional ability varied widely. Other non-physiotherapy related issues were identified in numerous patients (ie, 34.9% of patients were at risk of depression) and multidisciplinary interventional approaches could be considered.Future plansThe current study has provided a comprehensive description of patients receiving FCP, using data collected from the novel PhysDB-FCP. Collected information can be used to facilitate microlevel to macrolevel programme evaluation and decisions. Although the PhysDB-FCP is promising, the tool requires optimisation before it is implemented regionally and/or nationally.</jats:sec

The complete mitochondrial genome of Epomophorus gambianus (Chiroptera: Pteropodidae) and its phylogenetic analysis.

The Gambian epauletted fruit bat, Epomophorus gambianus, is widely distributed across sub-Saharan Africa. Its assembled and annotated mitochondrial genome (GenBank accession no. KT963027) is 16,702 bases in length, containing 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two non-coding regions: the control region (D-loop) and the origin of light-strand replication (OL). The average base composition is 32.2% A; 27.6% C; 14% G; and 26.1% T. The mitogenome presented a structural composition greatly conserved between members of the Pteropodidae family.This is the final version of the article. It first appeared from Taylor & Francis via https://doi.org/10.1080/23802359.2016.118199

Constraints on Non-Newtonian Gravity from Recent Casimir Force Measurements

Corrections to Newton's gravitational law inspired by extra dimensional physics and by the exchange of light and massless elementary particles between the atoms of two macrobodies are considered. These corrections can be described by the potentials of Yukawa-type and by the power-type potentials with different powers. The strongest up to date constraints on the corrections to Newton's gravitational law are reviewed following from the E\"{o}tvos- and Cavendish-type experiments and from the measurements of the Casimir and van der Waals force. We show that the recent measurements of the Casimir force gave the possibility to strengthen the previously known constraints on the constants of hypothetical interactions up to several thousand times in a wide interaction range. Further strengthening is expected in near future that makes Casimir force measurements a prospective test for the predictions of fundamental physical theories.Comment: 20 pages, crckbked.cls is used, to be published in: Proceedings of the 18th Course of the School on Cosmology and Gravitation: The Gravitational Constant. Generalized Gravitational Theories and Experiments (30 April- 10 May 2003, Erice). Ed. by G. T. Gillies, V. N. Melnikov and V. de Sabbata, 20pp. (Kluwer, in print, 2003

Comparison between 2000 and 2018 on the reporting of statistical significance and clinical relevance in physiotherapy clinical trials in six major physiotherapy journals: a meta-research design

DesignMeta-research.ObjectiveTo compare the prevalence of reporting p values, effect estimates and clinical relevance in physiotherapy randomised controlled trials (RCTs) published in the years 2000 and 2018.MethodsWe performed a meta-research study of physiotherapy RCTs obtained from six major physiotherapy peer-reviewed journals that were published in the years 2000 and 2018. We searched the databases Embase, Medline and PubMed in May 2019, and extracted data on the study characteristics and whether articles reported on statistical significance, effect estimates and confidence intervals for baseline, between-group, and within-group differences, and clinical relevance. Data were presented using descriptive statistics and inferences were made based on proportions. A 20% difference between 2000 and 2018 was regarded as a meaningful difference.ResultsWe found 140 RCTs: 39 were published in 2000 and 101 in 2018. Overall, there was a high prevalence (>90%) of reporting p values for the main (between-group) analysis, with no difference between years. Statistical significance testing was frequently used for evaluating baseline differences, increasing from 28% in 2000 to 61.4% in 2018. The prevalence of reporting effect estimates, CIs and the mention of clinical relevance increased from 2000 to 2018 by 26.6%, 34% and 32.8% respectively. Despite an increase in use in 2018, over 40% of RCTs failed to report effect estimates, CIs and clinical relevance of results.ConclusionThe prevalence of using p values remains high in physiotherapy research. Although the proportion of reporting effect estimates, CIs and clinical relevance is higher in 2018 compared to 2000, many publications still fail to report and interpret study findings in this way.</jats:sec

Pain relief is associated with decreasing postural sway in patients with non-specific low back pain

Background Increased postural sway is well documented in patients suffering from non-specific low back pain, whereby a linear relationship between higher pain intensities and increasing postural sway has been described. No investigation has been conducted to evaluate whether this relationship is maintained if pain levels change in adults with non-specific low back pain. Methods Thirty-eight patients with non-specific low back pain and a matching number of healthy controls were enrolled. Postural sway was measured by three identical static bipedal standing tasks of 90 sec duration with eyes closed in narrow stance on a firm surface. The perceived pain intensity was assessed by a numeric rating scale (NRS-11). The patients received three manual interventions (e.g. manipulation, mobilization or soft tissue techniques) at 3-4 day intervals, postural sway measures were obtained at each occasion. Results A clinically relevant decrease of four NRS scores in associated with manual interventions correlated with a significant decrease in postural sway. In contrast, if no clinically relevant change in intensity occurred ([less than or equal to]1 level), postural sway remained similar compared to baseline. The postural sway measures obtained at follow-up sessions 2 and 3 associated with specific NRS level showed no significant differences compared to reference values for the same pain score. Conclusions Alterations in self-reported pain intensities are closely related to changes in postural sway. The previously reported linear relationship between the two variables is maintained as pain levels change. Pain interference appears responsible for the altered sway in pain sufferers. This underlines the clinical use of sway measures as an objective monitoring tool during treatment or rehabilitation