An exploration of the effect of proprioceptive knee bracing on biomechanics during a badminton lunge to the net, and the implications to injury mechanisms

[EN] The aim of this study was to determine changes in knee biomechanics during badminton lunges due to fatigue, lunge strategy and knee bracing. Kinetic and kinematic data were collected from sixteen experienced right-handed badminton players. Three factor repeated measures ANOVAs (lunge direction – fatigue – brace) were performed with Least Significant Difference pairwise comparisons. In addition, clinical assessments including; Y-balance test, one leg hop distance and ankle dorsiflexion range of motion were performed pre and post fatigue. The knee showed significantly greater flexion during the forehand lunge compared to backhand. In contrast, the internal rotation velocity and the knee extension moment were greater during backhand. Knee angular velocity in the sagittal plane, peak knee moment and range of moment in the coronal plane and stance time showed significantly lower values post fatigue. In addition, the peak knee adduction moment showed significantly lower values in the braced condition in both the fatigued and non-fatigues states, and no significant differences were seen for peak vertical force, loading rate, approach velocity, or in any of the clinical assessment scores. There appears to be greater risk factors when performing a backhand lunge to the net compared to a forehand lunge, and proprioceptive bracing appears to reduce the loading at the knee.SIThis work was supported by Generalitat Valenciana ACIF projects [Grants number ACIF2016/121 and BEFPI 2017/014] and Valencia Catholic University ‘San Vicente Mártir’ pre-competitive grants for research groups

The intracellular chloride ion channel protein CLIC1 undergoes a redox-controlled structural transition.

Most proteins adopt a well defined three-dimensional structure; however, it is increasingly recognized that some proteins can exist with at least two stable conformations. Recently, a class of intracellular chloride ion channel proteins (CLICs) has been shown to exist in both soluble and integral membrane forms. The structure of the soluble form of CLIC1 is typical of a soluble glutathione S-transferase superfamily protein but contains a glutaredoxin-like active site. In this study we show that on oxidation CLIC1 undergoes a reversible transition from a monomeric to a non-covalent dimeric state due to the formation of an intramolecular disulfide bond (Cys-24-Cys-59). We have determined the crystal structure of this oxidized state and show that a major structural transition has occurred, exposing a large hydrophobic surface, which forms the dimer interface. The oxidized CLIC1 dimer maintains its ability to form chloride ion channels in artificial bilayers and vesicles, whereas a reducing environment prevents the formation of ion channels by CLIC1. Mutational studies show that both Cys-24 and Cys-59 are required for channel activity

Safety, immunogenicity, and efficacy of a COVID-19 vaccine (NVX-CoV2373) co-administered with seasonal influenza vaccines: an exploratory substudy of a randomised, observer-blinded, placebo-controlled, phase 3 trial

Background: Safety and immunogenicity of COVID-19 vaccines when co-administered with influenza vaccines have not yet been reported. Methods: A sub-study on influenza vaccine co-administration was conducted as part of the phase 3 randomised trial of NVX-CoV2373’s safety and efficacy; ~400 participants meeting main study entry criteria, with no contraindications to influenza vaccination, were enroled. After randomisation to receive NVX-CoV2373 or placebo, sub-study participants received an open-label influenza vaccine at the same time as the first dose of NVX-CoV2373. Reactogenicity was evaluated for 7 days post-vaccination plus monitoring for unsolicited adverse events (AEs), medically-attended AEs (MAAEs), and serious AEs (SAEs). Vaccine efficacy against COVID-19 was assessed. Findings: Sub-study participants were younger (median age 39; 6.7 % ≥65 years), more racially diverse, and had fewer comorbid conditions than main study participants. Reactogenicity events more common in co-administration group included tenderness (70.1% vs 57.6%) or pain (39.7% vs 29.3%) at injection site, fatigue (27.7% vs 19.4%), and muscle pain (28.3% vs 21.4%). Rates of unsolicited AEs, MAAEs, and SAEs were low and balanced between the two groups. Co-administration resulted in no change to influenza vaccine immune response, while a reduction in antibody responses to the NVX-CoV2373 vaccine was noted. Vaccine efficacy against COVID-19 was 87.5% (95% CI: -0.2, 98.4) in those 18-<65 years in the sub-study while efficacy in the main study was 89.8% (95% CI: 79.7, 95.5).  Interpretation: This is the first study to demonstrate safety, immunogenicity, and efficacy of a COVID-19 vaccine when co-administered with influenza vaccines

CSP2023: 19 Are HbA1c & deprivation associated with mortality in type two diabetic hemiarthroplasty, hip fracture, patients. Single centre retrospective cohort study

Purpose: The purpose of this study were to investigated if living in a more deprived area (measured by the index of multiple deprivation was associated with a higher mortality at 30 days and 1 year and if having a very low (64 mmol/mol) was associated with a higher mortality at 30 days and 1 year. The second aim was to explore if there was a connection between HbA1c and the index of multiple deprivation. Methods: This was a single centre retrospective cohort study. 183 patients were included in the deprivation analysis and 62 patients were included in the HbA1c analysis and correlation analysis. Data was grouped based on 30-day mortality, 1 year mortality and survival past 1 year and the Mann Whitney test was used to analyse if there was a statistically significant difference in the index of multiple deprivation and HbA1c readings between groups. A Pearson correlation was used to analyse the correlation between the index of multiple deprivation and HbA1c. Results: No statistically significant difference in the index of multiple deprivation or HbA1c was found between those who died at 30 days, 1 year or survived past 1 year. No statistically significant connection was found between IMD and HbA1c. Conclusion(s): These results suggest that HbA1c and deprivation do not affect mortality in T2DM hemiarthroplasty hip fracture patients who are over 65 but more investigation is required. Furthermore, the results suggest that being more deprived does not lead to worse HbA1c control. Impact: Both in inpatient (acute and rehabilitation settings) as well as outpatient settings, fragility hip fracture patients or those at risk of fragility fractures with diabetes are seen frequently seen, often on a daily basis. Yet our understanding of what leads to an increased risk of mortality post hip fracture, in this complex ageing population which we encounter and treat is limited. This study provides a more nuanced understanding of the influence of deprivation on mortality post hip fracture in those with type 2 diabetes, providing more up to date evidence from the north west of England within the diabetic population. The study of HbA1c also provides evidence where limited research has been completed previously, suggesting that HbA1c does not influence mortality in this increasingly prevalent (yet understudied) population. Finally, it suggests that factors other than HbA1c and deprivation may be more influential on mortality post fracture, indicating that more research is required within this field

The effect of three different (-135-degrees-C) whole body cryotherapy exposure durations on elite rugby league players

Background: Whole body cryotherapy (WBC) is the therapeutic application of extreme cold air for a short duration. Minimal evidence is available for determining optimal exposure time. Purpose: To explore whether the length of WBC exposure induces differential changes in inflammatory markers, tissue oxygenation, skin and core temperature, thermal sensation and comfort. Method: This study was a randomised cross over design with participants acting as their own control. Fourteen male professional first team super league rugby players were exposed to 1, 2, and 3 minutes of WBC at -135°C. Testing took place the day after a competitive league fixture, each exposure separated by seven days. Results: No significant changes were found in the inflammatory cytokine interleukin six. Significant reductions (p<0.05) in deoxyhaemoglobin for gastrocnemius and vastus lateralis were found. In vastus lateralis significant reductions (p<0.05) in oxyhaemoglobin and tissue oxygenation index (p<0.05) were demonstrated. Significant reductions (p<0.05) in skin temperature were recorded. No significant changes were recorded in core temperature. Significant reductions (p<0.05) in thermal sensation and comfort were recorded. Conclusion: Three brief exposures to WBC separated by 1 week are not sufficient to induce physiological changes in IL-6 or core temperature. There are however significant changes in tissue oxyhaemoglobin, deoxyhaemoglobin, tissue oxygenation index, skin temperature and thermal sensation. We conclude that a 2 minute WBC exposure was the optimum exposure length at temperatures of -135°C and could be applied as the basis for future studies

Differences in skin temperature responses during three different (-135°c) whole body cryotherapy exposure durations in elite rugby league players

Background Growing ever popular within elite sports, Whole Body Cryotherapy (WBC) is the therapeutic application of extreme cold air for a short duration. Minimal evidence is available for determining the physiological effects of WBC, including observation of skin surface and core temperature changes, in particular across specific pre-determined regions of interest. This study aimed to investigate the effects of three different (-135°C) whole body cryotherapy exposure durations on skin surface and core body temperatures in a group of elite rugby league players. Methods and Results 14 male professional first team super league rugby players were exposed to 1, 2 and 3 minutes of WBC at -135°C. Each WBC exposure was separated by seven days, and followed a competitive league fixture. Via ingestion of a core temperature pill, core body temperature was recorded pre, immediately post and 20 minutes post WBC. Non-contact, digital infrared thermal imaging measured skin surface temperature (Tsk). Tsk was measured pre, immediately post and every five minutes post WBC exposure, up to 20 minutes. Regions of interest were defined by attaching wooden markers to specific anatomical landmarks. Four regions of interest were defined; anterior triangle of the neck (A), torso (B), lower abdomen (C) and the back (D). Significant reductions (p=<0.05) in mean Tsk were noted after each exposure duration. Average Tsk over time demonstrated significant differences (p=<0.05) between pre and immediately post exposure time points, for each exposure. When comparing regions of interest significant differences (p=<0.05) were found in mean Tsk. When comparing average Tsk of lower abdomen with A, B and D, significant differences (p=<0.05) were determined. No significant differences were noted between B and D. No Significant differences were noted in core temperature. Discussion and Conclusion In all four regions of interest, Tsk was reduced following all exposure durations of WBC. The effectiveness of WBC in reducing Tsk has been demonstrated in previous studies; in the current study the lowest Tsk recorded was 12.1°C, in the lower abdomen following a 3 minute exposure of WBC. This demonstrates the ability of WBC to achieve skin cooling within a desired therapeutic range, which is a key claim of WBC, as part of a recovery method within elite sport. The pattern of change and differences in average Tsk across C against A, B and D was interesting. In particular vascular shunting to protect vital organs in areas A and B could be a suggestion as to why Tsk differed following WBC exposures. Core temperature did not significantly fluctuate following exposures of WBC. However, a small rise was observed in all exposures, illustrating a relationship with the drop in Tsk, and the body’s ability to maintain the function of vital organs. A phase of rewarming occurred following WBC exposures with post mean Tsk at 20 minutes not reaching pre exposure mean Tsk. Although lower limb Tsk was not measured in this study, these findings may have implications for clinicians deciding when it is safe to return an athlete to functional tasks following WBC, to reduce the risk of potential injury

The Intracellular Chloride Ion Channel Protein CLIC1 Undergoes a Redox-controlled Structural Transition

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