Using Machine Learning to Quantify Transverse Plane Lumbopelvic Rhythm

Lumbopelvic rhythm illustrates the relative motion between the lumbar spine and pelvis during various activities and could be used as a biomarker for low back pain (LBP). Sagittal plane lumbopelvic rhythm has been extensively examined as a surrogate to measure low back pain risk factor, but trunk rotation, the second component of lifting is commonly missed. Since lumbopelvic rhythm are time series and not discrete variables, machine learning may be a viable solution in identifying clusters of patterns for healthy adults. PURPOSE: To categorize healthy lumbopelvic rhythm in the transverse plane using machine learning. METHODS: 80 adults with no history of LBP (Young: n = 46; 26.9 ± 6.9 yr; Middle-Age: n = 33; 52.4 ± 6.9 yr). 3D kinematics of the lumbar spine and pelvis were calculated as participants performed maximal trunk rotation from right to left. Coupling angles were calculated using vector coding and represented in 4 coordination patterns (in-phase, anti-phase, superior-only, inferior-only). K-means clustering (k = 3) was used to segment coupling angles into clusters. Within each cluster, the age groups were compared. RESULTS: 3 distinct movement patterns were discovered (Figure 1). Lumbar spine and pelvis mostly moved in-phase, but for cluster 1, the start and end of the lumbar and pelvis was in anti-phase, while cluster 2 and 3 started and ended in-phase. Cluster 2 switched from in- to anti- and back to in-phase in the start and during transitioning directions. Age differences were seen only in cluster 1 where young and middle-age adults started rotation in anti-phase, but middle-age adults ended the rotation by only moving the lumbar spine and young adults ended in anti-phase. CONCLUSION: These movement patterns represent the different ways a healthy individual may perform trunk rotation, which along with sagittal plane motion can potentially be used to identify individuals with LBP.https://digitalcommons.odu.edu/gradposters2021_healthsciences/1007/thumbnail.jp

Adult-Acquired Flatfoot Deformity and Age-Related Differences in Foot and Ankle Kinematics During the Single-Limb Heel-Rise Test

STUDY DESIGN: Cross-sectional laboratory study. OBJECTIVE: To compare single-limb heel-rise performance and foot-ankle kinematics between persons with stage 2 adult-acquired flatfoot deformity (AAFD) and healthy controls. BACKGROUND: The inability to perform a single-limb heel rise is considered a positive functional diagnostic test for AAFD. However, which foot motions contribute to poor performance of this task are not known. METHODS: Fifty individuals participated in this study, 20 with stage 2 AAFD (mean +/- SD age, 57.6 +/- 11.3 years), and 15 older participants (age, 56.8 +/- 5.3 years) and 15 younger participants (age, 22.2 +/- 2.4 years) without AAFD as control groups. Forefoot (sagittal plane) and rearfoot (sagittal and frontal planes) kinematics were collected using a 3-D motion analysis system. Heel-rise performance (heel height) and kinematics (joint angles, excursions) were evaluated. One-way and 2-way analyses of variance were used to examine differences in heel-rise performance and kinematics between groups. RESULTS: Individuals with AAFD and older controls demonstrated lower heel-rise height than those in the younger control group (P\u3c.001). Persons with AAFD demonstrated higher degrees of first metatarsal dorsiflexion (P\u3c.001), lower ankle plantar flexion (P\u3c.001), and higher subtalar eversion (P = .027) than those in the older control group. Persons with AAFD demonstrated lower ankle excursion (P\u3c.001) and first metatarsal excursion (P\u3c.001) than those in the older control group, but no difference in subtalar excursion (P = .771). CONCLUSION: Persons with stage 2 AAFD did not achieve sufficient heel height during a single-leg heel rise. Both forefoot and rearfoot kinematics in the sagittal plane, as opposed to the frontal plane, contributed to the lower heel height in participants with stage 2 AAFD. Older controls demonstrated lower heel-rise height than younger controls, indicating that clinical expectations of heel-rise performance may need to be adjusted for age

Different Impacts of Boot Height and Air Bottles on the Mobility of Tall and Short Firefighters

This study conducted biomechanical tests with 21 firefighters and found that there is a significant correlation between boot height and lower body mobility, and that using a fixed boot height mandated by NFPA 1971 standard decreased lower body ranges of motion during various firefighters\u27 job-related tasks. Statistical analysis of large anthropometric data also shows a fixed boot height cannot accommodate a wide range of firefighters\u27 leg length. These findings indicate that shorter firefighters are likely to have limited lower body mobility due to reduced clearance between the knee and top of the boot, and thus decreased space causing greater mechanical binding between multiple layers of turnout pants. This study also shows a greater negative impact of fixed length of SCBA cylinder on short firefighters on their upper body mobility, evidenced by limited range of motion in neck extension and lumbopelvic flexion while carrying firegear compared to without any firegear

Altered Tendon Characteristics and Mechanical Properties Associated with Insertional Achilles Tendinopathy

Study Design: Case-control laboratory study. Objectives: To compare tendon characteristics (shape, composition) and mechanical properties (strain, stiffness) on the involved side of participants with insertional Achilles tendinopathy (IAT) to the uninvolved side and to controls, and to examine if severity of tendon pathology is associated with severity of symptoms during function. Background: Despite the severity and chronicity of IAT, the quality of theoretical evidence available to guide the development of exercise interventions is low. While tendon pathology of midportion Achilles tendinopathy has been described, there are few studies specific to IAT. Methods: Twenty individuals with unilateral IAT and 20 age- and sex-matched controls volunteered to participate. Ultrasound imaging was used to quantify changes in tendon shape (diameter) and composition (echogenicity). A combination of ultrasound and dynamometry was used to measure tendon mechanical properties (strain and stiffness) during passive ankle rotation toward dorsiflexion. Generalized estimating equations were used to examine the association between IAT, alterations in tendon properties, and participant demographics. Pearson correlation was used to examine the association between severity of tendon pathology and severity of symptoms (Victorian Institute of Sport Assessment-Achilles). Results: The side with IAT had a larger tendon diameter (P Conclusion: Ultrasound imaging combined with dynamometry can discriminate alterations in tendon shape, composition, and mechanics in participants with IAT. Future clinical trials for IAT may consider strategies to alter tendon characteristics and restore tendon mechanic

Management of the ataxias : towards best clinical practice

This document aims to provide recommendations for healthcare professionals on the diagnosis and management of people with progressive ataxia. The progressive ataxias are rare neurological conditions, and are often poorly understood by healthcare professionals. Diagnosis has generally been a long process because of the rarity and complexity of the different ataxias1. In addition, many healthcare professionals are unsure how best to manage the conditions and there is sometimes a feeling that little can be done for these patients1,2 Although there are no disease-modifying treatments for the majority of the progressive ataxias, there are many aspects of the conditions that are treatable and it is thus important that this is recognised by the relevant healthcare professionals. The diagnosis and management of the few treatable causes is also of paramount importance. All this highlights the importance of producing these guidelines: in order to increase awareness and understanding of these conditions, and lead to their improved diagnosis and management. With new developments in genetic technologies and the discovery of more genes, diagnosis is improving and has great scope to continue to do so. In addition, research is advancing and many human trials to test medications are taking place, making us more optimistic that disease-modifying treatments will be found for the progressive ataxias

Production and use of antigen tetramers to study antigen-specific B cells

38 Pág.B cells generate antibodies that provide protection from infection, but also cause pathology in autoimmune and allergic conditions. Antigen-specific B cells can be detected by binding their surface antibody receptors with native antigens conjugated to fluorescent probes, a technique that has revealed substantial insight into B cell activation and function. This protocol describes the process of generating fluorescent antigen tetramer probes and delineates a process of enriching large samples based on antigen-specificity for high-resolution analyses of the antigen-specific B cell repertoire. Enrichment of tetramer-binding cells allows for detection of antigen-specific B cells as rare as 1 in 100 million cells, providing sufficient resolution to study naive B cells and IgE-expressing cells by flow cytometry. The generation of antigen tetramers involves antigen biotinylation, assessment of biotin:antigen ratio for optimal tetramer loading and polymerization around a streptavidin-fluorophore backbone. We also describe the construction of a control tetramer to exclude B cells binding to the tetramer backbone. We provide a framework to validate whether tetramer probes are detecting true antigen-specific B cells and discuss considerations for experimental design. This protocol can be performed by researchers trained in basic biomedical/immunological research techniques, using instrumentation commonly found in most laboratories. Constructing the antigen and control tetramers takes 9 h, though their specificity should be assessed before experimentation and may take weeks to months depending on the method of validation. Sample enrichment requires ~2 h but is generally time and cost neutral as fewer cells are run through the flow cytometer.We thank J. SoRelle (University of Texas Southwestern) for carefully reviewing and providing suggestions on the manuscript. We thank M. K. Jenkins (University of Minnesota) for supporting the initial development of these protocols and for the inclusion of Extended Data Fig. 1g. We thank J. Carter and D. Galloway (Fred Hutchinson Cancer Center) for providing supernatant containing GST. We thank the McMaster Flow Cytometry Core, H. Liang and M. Subapanditha for access to flow cytometers and experimental support. We thank M. S. Miller (McMaster University) and M. Larche (McMaster University) for providing recombinant RBD. The laboratories of M.J. and J.F.E.K. are funded by the Schroeder Foundation, Food Allergy Canada, ALK-Abello A/S, the Canadian Allergy Asthma and Immunology Foundation, the Zych family and the Satov family. A.P. is funded by an Ontario Graduate Scholarship and The Eva Eugenia Lillian Cope Scholarship. D.P.-C. was funded by Universidad Politécnica de Madrid and Banco Santander with predoctoral and travel Programa Propio grants. J.T.-A. was funded by Severo Ochoa Program (Production of Plant and Human health-relevant proteins in Super-Green Biofactories: PCD-UPM/7/2022). The Centre for Plant Biotechnology and Genomics was granted ‘Severo Ochoa’ Distinctions of Excellence by the Spanish Ministry of Science and Innovation (SEV-2016-0672 and CEX2020-000999-S). J.J.T. has been funded by the National Institutes of Health (R01AI122912, R01AI158728, R01AI167009), The Hartwell Foundation, Vir Biotechnology, Fred Hutch Cancer Center and generous donors. J.B. was supported by a Fast Grants award, and J.B. and J.J.T. were supported by a Fred Hutchinson Cancer Center COVID pilot award.Peer reviewe

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials.

Funder: laura and john arnold foundationBACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Biomechanical and physiological load carrying efficiency of two firefighter harness variations

Firefighters and military personnel employ multiple backpack designs for carrying air tanks along with other heavy gear for occupational purposes. As the load increases, the biomechanical and physiological demands on the carrier change as well. The xPk® harness, a new design, claims to improve the load carriage ability for firefighters by allowing the load to be carried closer to the individual’s center of mass (COM) thus reducing the energy cost and increasing comfort level compared with the traditional design. The study compared biomechanical and physiological differences during walking at 1.79m/s (4 mph) at different grades, while carrying a firefighter air tank in traditional harness to xPk® double strap harnesses. There were significant differences in grade kinematics, but differences between old and new harnesses were minor. The minimal differences and subjective preference for xPk® could potentially be helpful in improving load carrying capacity without having to retrain carrying mechanics

Different Impacts of Boot Height and Air Bottles on the Mobility of Tall and Short Firefighters

This study conducted biomechanical tests with 21 firefighters and found that there is a significant correlation between boot height and lower body mobility, and that using a fixed boot height mandated by NFPA 1971 standard decreased lower body ranges of motion during various firefighters' job-related tasks. Statistical analysis of large anthropometric data also shows a fixed boot height cannot accommodate a wide range of firefighters' leg length. These findings indicate that shorter firefighters are likely to have limited lower body mobility due to reduced clearance between the knee and top of the boot, and thus decreased space causing greater mechanical binding between multiple layers of turnout pants. This study also shows a greater negative impact of fixed length of SCBA cylinder on short firefighters on their upper body mobility, evidenced by limited range of motion in neck extension and lumbopelvic flexion while carrying firegear compared to without any firegear.</p