92 research outputs found
The History of Biomechanics in Total Hip Arthroplasty.
Biomechanics of the hip joint describes how the complex combination of osseous, ligamentous, and muscular structures transfers the weight of the body from the axial skeleton into the appendicular skeleton of the lower limbs. Throughout history, several biomechanical studies based on theoretical mathematics, in vitro, in vivo as well as in silico models have been successfully performed. The insights gained from these studies have improved our understanding of the development of mechanical hip pathologies such as osteoarthritis, hip fractures, and developmental dysplasia of the hip. The main treatment of end-stage degeneration of the hip is total hip arthroplasty (THA). The increasing number of patients undergoing this surgical procedure, as well as their demand for more than just pain relief and leading an active lifestyle, has challenged surgeons and implant manufacturers to deliver higher function as well as longevity with the prosthesis. The science of biomechanics has played and will continue to play a crucial and integral role in achieving these goals. The aim of this article, therefore, is to present to the readers the key concepts in biomechanics of the hip and their application to THA
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Continuation vs Discontinuation of Renin-Angiotensin System Inhibitors Before Major Noncardiac Surgery
ImportanceBefore surgery, the best strategy for managing patients who are taking renin-angiotensin system inhibitors (RASIs) (angiotensin-converting enzyme inhibitors or angiotensin receptor blockers) is unknown. The lack of evidence leads to conflicting guidelines.ObjectiveTo evaluate whether a continuation strategy vs a discontinuation strategy of RASIs before major noncardiac surgery results in decreased complications at 28 days after surgery.Design, setting, and participantsRandomized clinical trial that included patients who were being treated with a RASI for at least 3 months and were scheduled to undergo a major noncardiac surgery between January 2018 and April 2023 at 40 hospitals in France.InterventionPatients were randomized to continue use of RASIs (n = 1107) until the day of surgery or to discontinue use of RASIs 48 hours prior to surgery (ie, they would take the last dose 3 days before surgery) (n = 1115).Main outcomes and measuresThe primary outcome was a composite of all-cause mortality and major postoperative complications within 28 days after surgery. The key secondary outcomes were episodes of hypotension during surgery, acute kidney injury, postoperative organ failure, and length of stay in the hospital and intensive care unit during the 28 days after surgery.ResultsOf the 2222 patients (mean age, 67 years [SD, 10 years]; 65% were male), 46% were being treated with angiotensin-converting enzyme inhibitors at baseline and 54% were being treated with angiotensin receptor blockers. The rate of all-cause mortality and major postoperative complications was 22% (245 of 1115 patients) in the RASI discontinuation group and 22% (247 of 1107 patients) in the RASI continuation group (risk ratio, 1.02 [95% CI, 0.87-1.19]; P = .85). Episodes of hypotension during surgery occurred in 41% of the patients in the RASI discontinuation group and in 54% of the patients in the RASI continuation group (risk ratio, 1.31 [95% CI, 1.19-1.44]). There were no other differences in the trial outcomes.Conclusions and relevanceAmong patients who underwent major noncardiac surgery, a continuation strategy of RASIs before surgery was not associated with a higher rate of postoperative complications than a discontinuation strategy.Trial registrationClinicalTrials.gov Identifier: NCT03374449
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Visibility of blood flow on optical coherence tomography angiography in a case of branch retinal artery occlusion
Purpose: We report the variability in flow angiogram during the course of branch retinal artery occlusion (BRAO) in a case imaged by optical coherence tomography angiography (OCTA).
Case Report: OCTA was performed in a patient with BRAO at initial examination and 6 hours later. Initially, the occluded retinal artery and its branches were not detected on OCTA whereas a slow perfusion was present on fluorescein angiography. Six hours after initial examination, flow was detected on OCTA image in the previously occluded artery.
Conclusion: This case confirmed the relevance of using OCTA in monitoring BRAO and showed that capillaries with a very slow flow are not visible on OCTA angiograms. It emphasizes that non-perfusion on OCTA should be interpreted with caution
Efficient header compression implementation for IP-based ITS communications
International audienceThe use of IP tunneling has incredibly increased during the last years. It is needed in some contexts such as IP-based ITS communication but implies overhead. This overhead can be reduced using some techniques as header compression. Among them, RoHC is the most advanced header compression standard wich support errorprone link. In this paper we describe our kernel implementation of an opensource RoHC library. We give the first performance results we obtainedwith our implementation and sketchup some of our future works
Motivators for and barriers to physical activity in people with knee osteoarthritis: A qualitative study
International audienc
Dynamic soaring mechanisms in the ocean boundary layer
Copyright © 2016 Inderscience Enterprises Ltd. Dynamic soaring is a flying technique which extracts energy from an environment where wind gradients form, such as the air-sea interface above oceans that sees such gradients developing through multiple and combined phenomena. Models of wind-wave interactions are analysed in terms of their influence on the induced wind field, before selecting a purely sinusoidal peak wave from the wave spectrum and developing the related wind field using stable laminar theory. Dynamic soaring trajectories are then derived by optimising a nonlinear constrained problem that models the evolution of a point mass vehicle. Characteristic phases of dynamic soaring flight are evidenced out of the overall trajectories and compared to the flat-ocean case in order to conclude on the influence of waves regarding dynamic soaring performances
French validation of the Arthritis Self-Efficacy Scale and further psychometric properties exploration among 168 people with osteoarthritis
International audienceObjective: To validate the Arthritis Self-Efficacy Scale-French version (ASES-F) of the ASES questionnaire designed to evaluate self-efficacy in arthritis population and to confirm its psychometric properties. Design: The translation/back-translation procedure was done in line with cross-cultural adaptation international guidelines. Prospective multicenter validation was performed on 168 patients with osteoarthritis who filled out the ASES-F. Function subscale of the Western Ontario and McMaster Universities Arthritis Index, Hospital Anxiety and Depression (HAD), Knee Osteoarthritis Fears and Beliefs Questionnaire, and pain on visual analog scale were collected. Acceptability, internal consistency, reproducibility, internal and external structure validity, and sensitivity following a self-management program focused on physical activity were analyzed. The retest was performed 15 days later. Results: A culturally adapted version was obtained following the validation procedure. The final translated questionnaire is available within the full article. Cronbach's alpha coefficient was at 0.95 for the overall ASES-F. Regarding the test-retest reproducibility, Lin's concordance coefficient was at 0.84. The internal and external validity was also explored with correlations at -0.50 between ASES-F and (WOMAC), and significant correlations between ASES-F and HAD. Sensitivity shown significant improvement at three months for the subscale function only (+2.65, P < 0.01). Conclusion: The ASES-F, French version of the ASES, available in supplemental data, was validated in knee osteoarthritis patients and could be used in clinical practice and research for French-speaking patients. Sensitivity needs to be more explored
Efficacy of two injection-site localisation techniques for botulinum toxin injections: a single-blind, crossover, randomised trial protocol among adults with hemiplegia due to stroke
This work was supported by CHU Clermont-Ferrand, and IPSEN provided funding for the ultrasoundINTRODUCTION: Botulinum toxin injections are an effective treatment for limb spasticity following stroke. Different tracking techniques are used for this purpose: palpation, electrostimulation, electromyography and ultrasound. Yet very few studies have compared these different techniques, and none has successfully proved the superior efficacy of ultrasound-guided injections compared to another tracking method. The primary objective of our study was therefore to compare the efficacy of botulinum toxin injections depending on the tracking technique used: ultrasound versus electrostimulation. METHODS AND ANALYSIS: This is a clinical, single-centre, prospective, interventional, single-blind, crossover, randomised trial. In total, 30 patients aged between 18 and 80 years presenting with triceps surae spasticity (evaluated >1 on the modified Ashworth scale) associated with hemiplegia sequelae due to stroke will be included. The patients will be selected among those who attend for consultation the Physical Medicine and Rehabilitation Department of the Clermont-Ferrand University Hospital. One group will receive the abobotulinumtoxinA (BoNT-A) injection guided by electrostimulation then ultrasound, and the second group's botulinum toxin injections will be guided by ultrasound then electrostimulation. For each patient, the duration of study participation is 5 months. The primary end point is variation in passive ankle dorsiflexion range of motion at slow and high speeds (Tardieu scale) with the knee straight. ETHICS AND DISSEMINATION: This study received ethics approval form the CPP of Rhones-Alpes region. Results will be published in a peer-reviewed journa
Toxoplasmic pachymeningitis with visual field impairment in a single-eyed patient and a literature review
To describe the clinical features of a patient with toxoplasmic pachymeningitis and provide a review of the recent cases of pachymeningitis in the literature.Retrospective, observational case report. A one-eyed patient who presented to our institution with blurred vision, floaters, and visual field shrinkage. Review of clinical, laboratory, perimetric, and radiologic records of the patient and description of the efficacy of antibiotic therapy. The signs of ocular impairment, including visual acuity, visual field, and magnetic resonance imaging (MRI) changes. A one-eyed patient who complained of blurred vision and unexplained visual field shrinkage was evaluated. The diagnosis of toxoplasmic pachymeningitis was confirmed by existence of a toxoplasmic seroconversion, cerebrospinal fluid abnormalities, radiological features, absence of other diagnoses, improvement of symptoms, and resolution of pachymeningitis in MRI with oral trimethoprim–sulfamethoxazole combination
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