The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Hugo Partsch - One of the best experts on this subject based on the ideXlab platform.
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a new two component compression system turning an elastic bandage into an inelastic compression device interface pressure stiffness and haemodynamic effectiveness
European Journal of Vascular and Endovascular Surgery, 2018Co-Authors: Giovanni Mosti, Hugo PartschAbstract:Introduction Bandage application does not exert consistent compression pressure, leading to extremely variable compression when applied to patients. A new elastic bandage can exert a predefined pressure independently of healthcare providers and the size of the wrapped limb. The bandage system includes a series of non-stretchable patches that when applied to the bandage make it stiff. The aim of this work was to assess, in an experimental setting, the venous ejection fraction (EF) from the lower leg and the tolerability of this new bandage in a group of patients affected by superficial venous incompetence. Methods EF was measured using strain gauge plethysmography under baseline conditions and the bandage was applied with a supine pressure of 20 and 30 mmHg, with and without the stiff patches, in 25 patients with severe venous reflux in the great saphenous vein. The interface pressure of the Bandages was measured simultaneously in the medial gaiter area. Results All patients showed EF values that were significantly reduced compared with normal individuals. Elastic Bandages with an average pressure of 20 and 30 mmHg in the supine position achieved a slight improvement in EF, and, after applying non-stretchable patches on the same bandage with similar resting pressure, EF was restored to its normal range ( p Conclusion This study confirms that inelastic is much more effective than elastic compression for improving impaired venous haemodynamics. The test material can be applied with a predetermined pressure, which considerably enhances the consistency of application, and it is easily transformed into an inelastic system just by applying stiff patches without any stretch and without significantly increasing the comfortable supine pressure.
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compression therapy in mixed ulcers increases venous output and arterial perfusion
Journal of Vascular Surgery, 2012Co-Authors: Giovanni Mosti, Maria Letizia Iabichella, Hugo PartschAbstract:Objectives This study was conducted to define bandage pressures that are safe and effective in treating leg ulcers of mixed arterial-venous etiology. Methods In 25 patients with mixed-etiology leg ulcers who received inelastic Bandages applied with pressures from 20 to 30, 31 to 40, and 41 to 50 mm Hg, the following measurements were performed before and after bandage application to ensure patient safety throughout the investigation: laser Doppler fluxmetry (LDF) close to the ulcer under the bandage and at the great toe, transcutaneous oxygen pressure (TcPo 2 ) on the dorsum of the foot, and toe pressure. Ejection fraction (EF) of the venous pump was performed to assess efficacy on venous hemodynamics. Results LDF values under the Bandages increased by 33% (95% confidence interval [CI], 17-48; P P P 41 mm Hg. Toe pressure values and TcPo 2 showed a moderate increase, excluding a restriction to arterial perfusion induced by the Bandages. Inelastic Bandages were highly efficient in improving venous pumping function, increasing the reduced ejection fraction by 72% (95% CI, 50%-95%; P P Conclusions In patients with mixed ulceration, an ankle-brachial pressure index >0.5 and an absolute ankle pressure of >60 mm Hg, inelastic compression of up to 40 mm Hg does not impede arterial perfusion but may lead to a normalization of the highly reduced venous pumping function. Such Bandages are therefore recommended in combination with walking exercises as the basic conservative management for patients with mixed leg ulcers.
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compression therapy in breast cancer related lymphedema a randomized controlled comparative study of relation between volume and interface pressure changes
Journal of Vascular Surgery, 2009Co-Authors: Robert J Damstra, Hugo PartschAbstract:Objective Short stretch Bandages are very effective in the initial management of arm lymphedema. However, no studies to date have measured the pressure required to achieve specific amounts of volume reduction. The purpose of this study was to determine whether there is a difference between low and high-pressure bandaging in terms of therapeutically intended volume reduction of the compressed arm. Methods Experimental, randomized and comparative study with two study-groups consisting of high and low initial interface pressure Bandages. Thirty-six hospitalized patients in Nij Smellinghe hospital suffering from moderate to severe unilateral breast cancer-related lymphedema not responsive to outpatient treatment were included. Bilateral arm volume was measured by inverse water volumetry before, after two hours and after 24 hours of bandaging. The amount of edema was calculated by subtracting the volume of the diseased arm from that of the contralateral side. Sub-bandage pressure was measured after bandage application and two hours later. Bandages were then re-applied and the pressure was measured again. Twenty-four hours later, the pressure measurement was repeated and Bandages were removed for final volumetry. Patients were randomized into two groups: group A received low pressure Bandages (20-30 mm Hg) and group B received high pressure Bandages (44-58 mm Hg). The main outcome measures were reduction of arm volume and edema volume in the affected arm in both study groups. Secondary outcome parameters were changes in sub-bandage pressure and patient comfort. Results Median arm volume reduction after two and 24 hours was 104.5 mL (95% confidence interval [CI], 51.2-184.2) (−2.5%) ( P P P Conclusions Inelastic, multi-layer, multi-component compression Bandages with lower pressure (20-30 mm Hg) are better tolerated and achieve the same amount of arm volume reduction as Bandages applied with higher pressure (44-58 mm Hg) in the first 24 hours.
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Classification of Compression Bandages: Practical Aspects
Dermatologic Surgery, 2008Co-Authors: Hugo Partsch, Giovanni Mosti, Erik Steinlechner, Jan Schuren, Benigni Jp, Philip Coleridge-smith, André Cornu-thenard, Michael Clark, Martin Abel, Mieke FlourAbstract:BACKGROUND: Compression Bandages appear to be simple medical devices. However, there is a lack of agreement over their classification and confusion over the use of important terms such as elastic, inelastic, and stiffness. OBJECTIVES: The objectives were to propose terms to describe both simple and complex compression bandage systems and to offer classification based on in vivo measurements of subbandage pressure and stiffness. METHODS: A consensus meeting of experts including members from medical professions and from companies producing compression products discussed a proposal that was sent out beforehand and agreed on by the authors after correction. RESULTS: Pressure, layers, components, and elastic properties (P-LA-C-E) are the important characteristics of compression Bandages. Based on simple in vivo measurements, pressure ranges and elastic properties of different bandage systems can be described. Descriptions of composite Bandages should also report the number of layers of bandage material applied to the leg and the components that have been used to create the final bandage system. CONCLUSION: Future descriptions of compression Bandages should include the subbandage pressure range measured in the medial gaiter area, the number of layers, and a specification of the bandage components and of the elastic property (stiffness) of the final bandage.
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Influence of Different Materials in Multicomponent Bandages on Pressure and Stiffness of the Final Bandage
Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.], 2008Co-Authors: Giovanni Mosti, Vincenzo Mattaliano, Hugo PartschAbstract:BACKGROUND The physical characteristics of bandage kits, in which different materials are combined, cannot be predicted by laboratory tests. They can only be assessed in vivo by measuring the interface pressure and calculation of stiffness. OBJECTIVE The objective was to investigate pressure and stiffness of some widely used multicomponent, multilayer Bandages and to investigate the effect of modifications of their components. METHODS AND MATERIALS Twelve healthy volunteers were investigated. Interface pressure and stiffness were measured in the lying and standing position after application of four-layer elastic bandage (Profore, Smith & Nephew, Hull, UK), two-layer elastic bandage (Proguide, Smith & Nephew), and four-layer short-stretch bandage (Rosidal sys, Lohmann & Rauscher GmbH, Neuwied, Germany) applied according to the manufacturer's recommendations and after some modifications of the padding layer. RESULTS Both Profore, made up of elastic, and Rosidal sys, made up of inelastic components, fulfill the criteria for Bandages with high stiffness. The stiffness of Proguide, consisting of elastic components, is in a gray zone between elastic and inelastic materials. Altering the padding layers changes the stiffness of these Bandages completely. CONCLUSION Pressure and stiffness of composite bandage kits differ from the physical properties of their components. Modifying the padding layers leads to a change of these physical properties that can only be assessed by in vivo tests on the human leg.
R Jayakumar - One of the best experts on this subject based on the ideXlab platform.
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exploration of alginate hydrogel nano zinc oxide composite Bandages for infected wounds
International Journal of Nanomedicine, 2015Co-Authors: Annapoorna Mohandas, Biswas Raja, Vinothkumar Lakshmanan, R JayakumarAbstract:Alginate hydrogel/zinc oxide nanoparticles (nZnO) composite bandage was developed by freeze-dry method from the mixture of nZnO and alginate hydrogel. The developed composite bandage was porous with porosity at a range of 60%-70%. The swelling ratios of the Bandages decreased with increasing concentrations of nZnO. The composite Bandages with nZnO incorporation showed controlled degradation profile and faster blood clotting ability when compared to the KALTOSTAT® and control Bandages without nZnO. The prepared composite Bandages exhibited excellent antimicrobial activity against Escherichia coli, Staphylococcus aureus, Candida albicans, and methicillin resistant S. aureus (MRSA). Cytocompatibility evaluation of the prepared composite Bandages done on human dermal fibroblast cells by Alamar assay and infiltration studies proved that the Bandages have a non-toxic nature at lower concentrations of nZnO whereas slight reduction in viability was seen with increasing nZnO concentrations. The qualitative analysis of ex-vivo re-epithelialization on porcine skin revealed keratinocyte infiltration toward wound area for nZnO alginate Bandages.
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evaluation of wound healing potential of β chitin hydrogel nano zinc oxide composite bandage
Pharmaceutical Research, 2013Co-Authors: P Sudheesh T Kumar, Vinothkumar Lakshmanan, Raja Biswas, Tamura Hiroshi, Shantikumar V Nair, R JayakumarAbstract:Purpose β-chitin hydrogel/nZnO composite bandage was fabricated and evaluated in detail as an alternative to existing Bandages.
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evaluation of wound healing potential of β chitin hydrogel nano zinc oxide composite bandage
Pharmaceutical Research, 2013Co-Authors: P Sudheesh T Kumar, Vinothkumar Lakshmanan, Raja Biswas, Tamura Hiroshi, Shantikumar V Nair, Mincy Raj, R JayakumarAbstract:β-chitin hydrogel/nZnO composite bandage was fabricated and evaluated in detail as an alternative to existing Bandages. β-chitin hydrogel was synthesized by dissolving β-chitin powder in Methanol/CaCl2 solvent, followed by the addition of distilled water. ZnO nanoparticles were added to the β-chitin hydrogel and stirred for homogenized distribution. The resultant slurry was frozen at 0°C for 12 h. The frozen samples were lyophilized for 24 h to obtain porous composite Bandages. The Bandages showed controlled swelling and degradation. The composite Bandages showed blood clotting ability as well as platelet activation, which was higher when compared to the control. The antibacterial activity of the Bandages were proven against Staphylococcus aureus (S. aureus) and Escherichia coli (E.coli). Cytocompatibility of the composite Bandages were assessed using human dermal fibroblast cells (HDF) and these cells on the composite Bandages were viable similar to the Kaltostat control Bandages and bare β-chitin hydrogel based Bandages. The viability was reduced to 50–60% in Bandages with higher concentration of zinc oxide nanoparticles (nZnO) and showed 80–90% viability with lower concentration of nZnO. In vivo evaluation in Sprague Dawley rats (S.D. rats) showed faster healing and higher collagen deposition ability of composite Bandages when compared to the control. The prepared Bandages can be used on various types of infected wounds with large volume of exudates.
Fanette Chassagne - One of the best experts on this subject based on the ideXlab platform.
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Numerical Model Reduction for the Prediction of Interface Pressure Applied by Compression Bandages on the Lower Leg
IEEE Transactions on Biomedical Engineering, 2018Co-Authors: Fanette Chassagne, Reynald Convert, Pascal Giraux, Jerome Molimard, Pierre BadelAbstract:Objective: To develop a new method for the prediction of interface pressure applied by medical compression Bandages. Methods: A finite element simulation of bandage application was designed, based on patient-specific leg geometries. For personalized interface pressure prediction, a model reduction approach was proposed, which included the parametrization of the leg geometry. Pressure values computed with this reduced model were then confronted to experimental pressure values. Results: The most influencing parameters were found to be the bandage tension, the skin-to-bandage friction coefficient and the leg morphology. Thanks to the model reduction approach, it was possible to compute interface pressure as a linear combination of these parameters. The pressures computed with this reduced model were in agreement with experimental pressure values measured on 66 patients' legs. Conclusion: This methodology helps to predict patient-specific interface pressure applied by compression Bandages within a few minutes whereas it would take a few days for the numerical simulation. The results of this method show less bias than Laplace's Law, which is for now the only other method for interface pressure computation.
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Superimposition of elastic and nonelastic compression Bandages.
Journal of vascular surgery. Venous and lymphatic disorders, 2017Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Jerome Molimard, Clothilde Helouin-desenne, Pascal GirauxAbstract:Abstract Objective The objective of this study was to investigate the pressure applied by superimposed Bandages and to compare it with the pressure applied by single-component Bandages. Methods Six different Bandages, composed of one elastic bandage, one nonelastic bandage, or both, were applied in a spiral pattern on both legs of 25 patients at risk of venous thrombosis as a consequence of central or peripheral motor deficiency. Pressure was measured at four measurement points on the leg (B1 and C on the medial and lateral sides of the leg) and in three positions: supine, sitting, and standing. Results The two single Bandages applied similar pressure in the supine position. Their superimposition showed different pressure levels ( P Conclusions The order of bandage application showed a significant impact on interface pressure. However, the poor correlation between the pressure applied by each bandage component and the pressure resulting from their superimposition underlined the poor understanding of interface pressure generated by the superimposition of compression Bandages and should lead to further investigations.
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Biomechanical study of the action of compression Bandages on the lower leg
2017Co-Authors: Fanette ChassagneAbstract:Compression Bandages are commonly used for the treatment of chronic venous insufficiency. They apply a pressure onto the leg, called interface pressure, which is one of the key aspects of the treatment. The objective was to better understand the mechanisms impacting interface pressure applied by compression bandage on the lower leg. In collaboration with clinicians and a medical devices manufacturer, a biomechanical approach was proposed. This approach was composed of experimental pressure measurements and the numerical simulation of bandage application. Two preliminary studies, experimental and numerical, showed the limitations of the use of Laplace’s Law (current standard) for interface pressure computation. These studies also questioned the possible impact of bandage surface properties (bandage-to-bandage friction coefficient) on interface pressure. They also showed the need to consider soft tissues deformation induced by bandage application. Two characterization methods were designed for the identification of patient-specific soft tissue mechanical properties and the measurement of bandage-to-bandage friction coefficient. A new methodology for the prediction of interface pressure was developed thanks to the combination of the numerical simulation of bandage application and the leg geometry parametrization. The results were then confronted to experimental measurements. Finally, a clinical study was designed to investigate the pressure applied by superimposed compression Bandages (very common in clinical practice for the treatment of venous ulcers).
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Modelisation of the action of compression Bandages on the lower limb
Annals of Physical and Rehabilitation Medicine, 2016Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Pascal Giraux, Jerome MolimardAbstract:Objective Compression Bandages are commonly used in the treatment of some venous or lymphatic pathologies. The success of the treatment relies on the applied pressure, which depends on several parameters, especially the bandage properties but also patients’ morphology. A previous experimental study showed that considering only patient's morphology and bandage elastic properties were not sufficient to explain interface pressure distribution. However, these two parameters are the only one taken into account in Laplace's Law, current standard method to explain interface pressure distribution. The objective of the study is to characterize and model compression Bandages pressure generation mechanisms. Material and methods A patient-specific numerical simulation of 4 Bandages application [Biflex ® 16 and Biflex ® 17 (Thuasne) applied with 2 and 3 layers on the leg] was developed for 5 subjects. The inputs of this simulation are the subjects’ morphology, the bandage's and soft tissues’ elastic properties and the application technique. The results of this simulation were then confronted to the experimental results and pressure values computed with Laplace's Law: P = nT/r, with P the pressure [N/mm 2 ], n the number of layers, T the bandage tension [N/mm] and r the local radius of curvature [mm]. Results The numerical simulation provides the complete pressure distribution over the leg but also considers the deformations of the leg, induced by bandage application. The comparison with the results given by Laplace's law highlighted the influence of these leg geometry changes on the applied pressure. However, the 4 parameters considered in this simulation (leg morphology and deformations, bandage elastic properties and application technique) are not sufficient to completely explain pressure generation, and differences with the experiments still persist. Discussion/Conclusion Numerical simulation still needs to be enriched to consider other parameters which may impact interface pressure such as bandage to bandage interaction for example.
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BIOMECHANICAL STUDY OF PRESSURE APPLIED ON THE LOWER LEG BY ELASTIC COMPRESSION Bandages
2016Co-Authors: Fanette ChassagneAbstract:Compression Bandages are a common treatment for some lymphatics or venous pathologies. The treatment success directly depends on the pressure which is applied on the external surface of the leg and which is then transmitted to the internal tissues. This interface pressure (between the limb and the bandage) depends mainly on the following parameters: - the bandage components (padding layers, …) - their mechanical properties - the bandage stretch - the application technique (spiral, …) and number of layers (overlap) - patient’s leg morphology - other parameters such as friction between the different bandage layers. Though the efficacy of this treatment is admitted [1], its action mechanism and the pressure it applies on the leg remain poorly understood [2]. For now, the reference method for the computation of interface pressure applied by compression bandage is Laplace’s Law: P = n T / r (1) with P the local pressure, n the number of layers of the bandage, T the bandage tension (i.e. force to stretch the bandage), r the local radius of curvature of the limb. However, this law, which only considers the non-deformed state of the limb, is unable to accurately predict interface pressures [3]. The aim of this communication is to present a combined experimental and numerical approach for the assessment of interface pressure applied by compression Bandages.
Pierre Badel - One of the best experts on this subject based on the ideXlab platform.
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Numerical Model Reduction for the Prediction of Interface Pressure Applied by Compression Bandages on the Lower Leg
IEEE Transactions on Biomedical Engineering, 2018Co-Authors: Fanette Chassagne, Reynald Convert, Pascal Giraux, Jerome Molimard, Pierre BadelAbstract:Objective: To develop a new method for the prediction of interface pressure applied by medical compression Bandages. Methods: A finite element simulation of bandage application was designed, based on patient-specific leg geometries. For personalized interface pressure prediction, a model reduction approach was proposed, which included the parametrization of the leg geometry. Pressure values computed with this reduced model were then confronted to experimental pressure values. Results: The most influencing parameters were found to be the bandage tension, the skin-to-bandage friction coefficient and the leg morphology. Thanks to the model reduction approach, it was possible to compute interface pressure as a linear combination of these parameters. The pressures computed with this reduced model were in agreement with experimental pressure values measured on 66 patients' legs. Conclusion: This methodology helps to predict patient-specific interface pressure applied by compression Bandages within a few minutes whereas it would take a few days for the numerical simulation. The results of this method show less bias than Laplace's Law, which is for now the only other method for interface pressure computation.
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Superimposition of elastic and nonelastic compression Bandages.
Journal of vascular surgery. Venous and lymphatic disorders, 2017Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Jerome Molimard, Clothilde Helouin-desenne, Pascal GirauxAbstract:Abstract Objective The objective of this study was to investigate the pressure applied by superimposed Bandages and to compare it with the pressure applied by single-component Bandages. Methods Six different Bandages, composed of one elastic bandage, one nonelastic bandage, or both, were applied in a spiral pattern on both legs of 25 patients at risk of venous thrombosis as a consequence of central or peripheral motor deficiency. Pressure was measured at four measurement points on the leg (B1 and C on the medial and lateral sides of the leg) and in three positions: supine, sitting, and standing. Results The two single Bandages applied similar pressure in the supine position. Their superimposition showed different pressure levels ( P Conclusions The order of bandage application showed a significant impact on interface pressure. However, the poor correlation between the pressure applied by each bandage component and the pressure resulting from their superimposition underlined the poor understanding of interface pressure generated by the superimposition of compression Bandages and should lead to further investigations.
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Modelisation of the action of compression Bandages on the lower limb
Annals of Physical and Rehabilitation Medicine, 2016Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Pascal Giraux, Jerome MolimardAbstract:Objective Compression Bandages are commonly used in the treatment of some venous or lymphatic pathologies. The success of the treatment relies on the applied pressure, which depends on several parameters, especially the bandage properties but also patients’ morphology. A previous experimental study showed that considering only patient's morphology and bandage elastic properties were not sufficient to explain interface pressure distribution. However, these two parameters are the only one taken into account in Laplace's Law, current standard method to explain interface pressure distribution. The objective of the study is to characterize and model compression Bandages pressure generation mechanisms. Material and methods A patient-specific numerical simulation of 4 Bandages application [Biflex ® 16 and Biflex ® 17 (Thuasne) applied with 2 and 3 layers on the leg] was developed for 5 subjects. The inputs of this simulation are the subjects’ morphology, the bandage's and soft tissues’ elastic properties and the application technique. The results of this simulation were then confronted to the experimental results and pressure values computed with Laplace's Law: P = nT/r, with P the pressure [N/mm 2 ], n the number of layers, T the bandage tension [N/mm] and r the local radius of curvature [mm]. Results The numerical simulation provides the complete pressure distribution over the leg but also considers the deformations of the leg, induced by bandage application. The comparison with the results given by Laplace's law highlighted the influence of these leg geometry changes on the applied pressure. However, the 4 parameters considered in this simulation (leg morphology and deformations, bandage elastic properties and application technique) are not sufficient to completely explain pressure generation, and differences with the experiments still persist. Discussion/Conclusion Numerical simulation still needs to be enriched to consider other parameters which may impact interface pressure such as bandage to bandage interaction for example.
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numerical approach for the assessment of pressure generated by elastic compression bandage
Annals of Biomedical Engineering, 2016Co-Authors: Reynald Convert, Fanette Chassagne, Pierre Badel, Pascal Giraux, Jerome MolimardAbstract:Compression of the lower leg by Bandages is a common treatment for the advanced stages of some venous or lymphatic pathologies. The outcomes of this treatment directly result from the pressure generated onto the limb. Various bandage configurations are proposed by manufacturers: the study of these configurations requires the development of reliable methods to predict pressure distribution applied by compression Bandages. Currently, clinicians and manufacturers have no dedicated tools to predict bandage pressure generation. A numerical simulation approach is presented in this work, which includes patient-specific leg geometry and bandage. This model provides the complete pressure distribution over the leg. The results were compared to experimental pressure measurements and pressure values computed with Laplace’s law. Using an appropriate surrogate model, this study demonstrated that such simulation is appropriate to account for phenomena which are neglected in Laplace’s law, like geometry changes due to bandage application.
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experimental investigation of pressure applied on the lower leg by elastic compression bandage
Annals of Biomedical Engineering, 2015Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Pascal Giraux, Frederic Martin, Jerome MolimardAbstract:Compression therapy with stockings or Bandages is the most common treatment for venous or lymphatic disorders. The objective of this study was to investigate the influence of bandage mechanical properties, application technique and subject morphology on the interface pressure, which is the key of this treatment. Bandage stretch and interface pressure measurements (between the bandage and the leg) were performed on 30 healthy subjects (15 men and 15 women) at two different heights on the lower leg and in two positions (supine and standing). Two Bandages were applied with two application techniques by a single operator. The statistical analysis of the results revealed: no significant difference in pressure between men and women, except for the pressure variation between supine and standing positions; a very strong correlation between pressure and bandage mechanical properties (p < 0.00001) and between pressure and bandage overlapping (p < 0.00001); a significant pressure increase from supine to standing positions (p < 0.0001). Also, it showed that pressure tended to decrease when leg circumference increased. Overall, pressure applied by elastic compression Bandages varies with subject morphology, bandage mechanical properties and application technique. A better knowledge of the impact of these parameters on the applied pressure may lead to a more effective treatment.
Jerome Molimard - One of the best experts on this subject based on the ideXlab platform.
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Numerical Model Reduction for the Prediction of Interface Pressure Applied by Compression Bandages on the Lower Leg
IEEE Transactions on Biomedical Engineering, 2018Co-Authors: Fanette Chassagne, Reynald Convert, Pascal Giraux, Jerome Molimard, Pierre BadelAbstract:Objective: To develop a new method for the prediction of interface pressure applied by medical compression Bandages. Methods: A finite element simulation of bandage application was designed, based on patient-specific leg geometries. For personalized interface pressure prediction, a model reduction approach was proposed, which included the parametrization of the leg geometry. Pressure values computed with this reduced model were then confronted to experimental pressure values. Results: The most influencing parameters were found to be the bandage tension, the skin-to-bandage friction coefficient and the leg morphology. Thanks to the model reduction approach, it was possible to compute interface pressure as a linear combination of these parameters. The pressures computed with this reduced model were in agreement with experimental pressure values measured on 66 patients' legs. Conclusion: This methodology helps to predict patient-specific interface pressure applied by compression Bandages within a few minutes whereas it would take a few days for the numerical simulation. The results of this method show less bias than Laplace's Law, which is for now the only other method for interface pressure computation.
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Superimposition of elastic and nonelastic compression Bandages.
Journal of vascular surgery. Venous and lymphatic disorders, 2017Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Jerome Molimard, Clothilde Helouin-desenne, Pascal GirauxAbstract:Abstract Objective The objective of this study was to investigate the pressure applied by superimposed Bandages and to compare it with the pressure applied by single-component Bandages. Methods Six different Bandages, composed of one elastic bandage, one nonelastic bandage, or both, were applied in a spiral pattern on both legs of 25 patients at risk of venous thrombosis as a consequence of central or peripheral motor deficiency. Pressure was measured at four measurement points on the leg (B1 and C on the medial and lateral sides of the leg) and in three positions: supine, sitting, and standing. Results The two single Bandages applied similar pressure in the supine position. Their superimposition showed different pressure levels ( P Conclusions The order of bandage application showed a significant impact on interface pressure. However, the poor correlation between the pressure applied by each bandage component and the pressure resulting from their superimposition underlined the poor understanding of interface pressure generated by the superimposition of compression Bandages and should lead to further investigations.
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Modelisation of the action of compression Bandages on the lower limb
Annals of Physical and Rehabilitation Medicine, 2016Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Pascal Giraux, Jerome MolimardAbstract:Objective Compression Bandages are commonly used in the treatment of some venous or lymphatic pathologies. The success of the treatment relies on the applied pressure, which depends on several parameters, especially the bandage properties but also patients’ morphology. A previous experimental study showed that considering only patient's morphology and bandage elastic properties were not sufficient to explain interface pressure distribution. However, these two parameters are the only one taken into account in Laplace's Law, current standard method to explain interface pressure distribution. The objective of the study is to characterize and model compression Bandages pressure generation mechanisms. Material and methods A patient-specific numerical simulation of 4 Bandages application [Biflex ® 16 and Biflex ® 17 (Thuasne) applied with 2 and 3 layers on the leg] was developed for 5 subjects. The inputs of this simulation are the subjects’ morphology, the bandage's and soft tissues’ elastic properties and the application technique. The results of this simulation were then confronted to the experimental results and pressure values computed with Laplace's Law: P = nT/r, with P the pressure [N/mm 2 ], n the number of layers, T the bandage tension [N/mm] and r the local radius of curvature [mm]. Results The numerical simulation provides the complete pressure distribution over the leg but also considers the deformations of the leg, induced by bandage application. The comparison with the results given by Laplace's law highlighted the influence of these leg geometry changes on the applied pressure. However, the 4 parameters considered in this simulation (leg morphology and deformations, bandage elastic properties and application technique) are not sufficient to completely explain pressure generation, and differences with the experiments still persist. Discussion/Conclusion Numerical simulation still needs to be enriched to consider other parameters which may impact interface pressure such as bandage to bandage interaction for example.
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numerical approach for the assessment of pressure generated by elastic compression bandage
Annals of Biomedical Engineering, 2016Co-Authors: Reynald Convert, Fanette Chassagne, Pierre Badel, Pascal Giraux, Jerome MolimardAbstract:Compression of the lower leg by Bandages is a common treatment for the advanced stages of some venous or lymphatic pathologies. The outcomes of this treatment directly result from the pressure generated onto the limb. Various bandage configurations are proposed by manufacturers: the study of these configurations requires the development of reliable methods to predict pressure distribution applied by compression Bandages. Currently, clinicians and manufacturers have no dedicated tools to predict bandage pressure generation. A numerical simulation approach is presented in this work, which includes patient-specific leg geometry and bandage. This model provides the complete pressure distribution over the leg. The results were compared to experimental pressure measurements and pressure values computed with Laplace’s law. Using an appropriate surrogate model, this study demonstrated that such simulation is appropriate to account for phenomena which are neglected in Laplace’s law, like geometry changes due to bandage application.
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experimental investigation of pressure applied on the lower leg by elastic compression bandage
Annals of Biomedical Engineering, 2015Co-Authors: Fanette Chassagne, Reynald Convert, Pierre Badel, Pascal Giraux, Frederic Martin, Jerome MolimardAbstract:Compression therapy with stockings or Bandages is the most common treatment for venous or lymphatic disorders. The objective of this study was to investigate the influence of bandage mechanical properties, application technique and subject morphology on the interface pressure, which is the key of this treatment. Bandage stretch and interface pressure measurements (between the bandage and the leg) were performed on 30 healthy subjects (15 men and 15 women) at two different heights on the lower leg and in two positions (supine and standing). Two Bandages were applied with two application techniques by a single operator. The statistical analysis of the results revealed: no significant difference in pressure between men and women, except for the pressure variation between supine and standing positions; a very strong correlation between pressure and bandage mechanical properties (p < 0.00001) and between pressure and bandage overlapping (p < 0.00001); a significant pressure increase from supine to standing positions (p < 0.0001). Also, it showed that pressure tended to decrease when leg circumference increased. Overall, pressure applied by elastic compression Bandages varies with subject morphology, bandage mechanical properties and application technique. A better knowledge of the impact of these parameters on the applied pressure may lead to a more effective treatment.
