An indirect testing approach for characterizing pressure profiles of compression bandages and hosiery

As outlined in compression therapy literature, the performance of a compression textile can be characterized by its stiffness and interface pressure. In this study, an indirect approach for measuring pressure from a set of compression bandages and hosiery was developed, from which rigidity (EI) values were determined, and tension–elongation curves and pressure-elongation data were calculated. The calculated pressure values were compared against PicoPress sensor readings measured on 10 participants. Results showed that the correlation between both approaches varied among bandage and hosiery samples.     

Comparison of compression properties of stretchable knitted fabrics and bi-stretch woven fabrics for compression garments

Stretchable fabrics have diverse applications ranging from casual apparel to performance sportswear and compression therapy. Compression therapy is the universally accepted treatment for the management of hypertrophic scarring after severe burns. Mostly stretchable knitted fabrics are used in compression therapy; but in the recent past, some studies have also been found on bi-stretch woven fabrics being used as compression garments as they also have been found quite effective in the treatment of edema. Therefore, the objective of the present study is to compare the compression properties of stretchable knitted and bi-stretch woven fabrics for compression garments. For this purpose, four woven structures and four knitted structures were produced having same areal density and their compression, comfort and mechanical properties were compared before and after 5, 10 and 15 washes. The four knitted structures used were single jersey, single locaste, plain pique and honeycomb, whereas the four woven structures produced were 1/1 plain, 2/1 twill, 3/1 twill and 4/1 twill. The compression properties of the produced samples were tested by using kikuhime pressure sensor and it was found that bi-stretch woven fabrics possessed better compression properties before and after washes and retain their durability after repeated use, whereas knitted stretchable fabrics lost their compression ability after repeated use and the required sub-garment pressure of the knitted structures after 15 washes was almost half that of woven bi-stretch fabrics.     

A study of the modelling and characterisation of compression garments for hypertrophic scarring after burns. Part 2: characterisation of compression garments

Compression therapy is the universally accepted treatment for the management of hypertrophic scarring after severe burns. A review of the type of treatments for burns and type of compression garments commercially available is discussed in Part 1 of this paper (Anand, Kanchi Govarthanam, & Gazioglu, in press). A refined model was also designed to predict the sub-garment pressure more accurately, irrespective of the shape and size of the limb (see Part 1, in press). The thermophysiological properties of the compression garment provide comfort by preserving body temperature and moisture output close to their normal levels. In this study, the dimensional, mechanical and thermophysiological properties of four fabrics procured from different sources were thoroughly studied and compared. The study was aimed at the determination of their suitability to be utilised for the management of hypertrophic scarring. It was established that one of the fabrics investigated possessed superior properties in comparison to the other three fabrics. It was also demonstrated that the characteristics of this particular fabric can be further enhanced for its suitability for use as a compression garment for this specific area of application.     

A study of the modelling and characterisation of compression garments for hypertrophic scarring after burns. Part 1: modelling of compression garments

Skin burns are usually caused by contact with fire, heat, electricity, light, radiation, hazardous chemicals and friction. The degree of the burn is classed based on the extent and depth of the burn. A third-degree burn is classed as a severe burn and compression therapy is universally accepted as the treatment to manage hypertrophic scarring caused after such burns. This paper describes the types of burns and the different types of treatments available and reviews the types of compression garments that are commercially available for the management of hypertrophic scarring after severe burns. The Laplace equation that is used to model a pattern-cutting chart has been refined to predict the sub-garment pressure more accurately, irrespective of the shape and size of the limb. This model’s accuracy was further validated by constructing garments for the arms and legs of a male volunteer and measuring the actual pressures by using a Kikuhime pressure measuring device.     

Interface pressure generated by knitted fabrics of different direction,composition and number of layers in sport compression garments

The present study aimed to determine the effect of fabric direction, fabric composition and number of fabric layers on pressure generated by sport compression garments. Experimental fabric used in commercially available compression sport garments was chosen. Experimental fabric sleeves imitating a part of a pressure garment were assembled and placed on cylinders of different diameters, so that they provided different fabric direction, fabric composition of sleeve and number of layers in assemblies along the circumference of the cylinders. A Salzmann MST MK IV pressure-measuring device and Salzmann MST 2007 software were used to measure the interface pressure generated by the sleeves. It was established that different direction, fabric composition of sleeve and number of fabric layers in fabric assemblies influences the interface pressure.     

An approach to examine dynamic behavior of medical compression bandage

Compression bandages are subjected to a repeated and prolonged spatial deformation, at knee and ankle positions, during ambulatory conditions of the lower limb. The important dynamic variables like speed, the amount of the degree of bending at knees and ankles, etc. could affect the long-term compression behavior of the bandage. The aim of this study was to investigate the dynamic behavior of medical compression bandage using a newly designed dynamic leg-segment model. A prototype was especially designed to simulate the dynamic behavior of the human leg using a mannequin limb. The influence of major factors, i.e. the speed of the reciprocating movement of the mannequin, the amount of displacement amplitude of the reciprocating movement of the mannequin (i.e. step size), and the applied extension level given to the bandage, on the sub-bandage pressure exerted by the bandage on the mannequin surface were analyzed using this model. It was observed that the rate and amount of the sub-bandage pressure drop increased under dynamic mode of the mannequin as compared to static mode. A higher drop in the sub-bandage pressure under dynamic mode was obtained with increasing the amount of displacement amplitude of the mannequin leg and also with increasing the applied extension level given to the bandage. The ambulatory conditions of the leg result in cyclic deformations in the wrapped bandage, and this influences the sub-bandage pressure variations over time. The proposed leg-segment model enables to assess dynamic behavior of different compression bandages under customized conditions and hence could be used for comparing and pre-evaluating different bandage products.     

Study on interface pressure generated by a bandage using in vitro pressure measurement system

This paper aims to identify and analyze various factors responsible for the variations in the interface pressure exerted by compression bandages during compression treatment. Some of the major factors, i.e. the applied force, the limb circumference, and the numbers of bandage layers wrapped, were chosen to analyze their impacts on the initial interface pressure and also on the interface pressure profile generated by compression bandages over time during static mode of the mannequin limb. The testing under static mode was done using a leg-segment prototype, which allows continuous online measurement of interface pressure exerted by the bandage over mannequin surface. The interface pressure variations under dynamic mode of the mannequin limb was also investigated using another dynamic leg-segment prototype which simulates the dynamic behavior of the human limb i.e. walking, jogging, running, etc. The investigation of stress relaxation and fatigue behavior of the bandage was examined to find their impacts on the bandage performance under static and dynamic conditions. The result of an N-way analysis of variance shows that the applied force and number of layers significantly affect the interface pressure drop over time. The interface pressure drop under dynamic mode is faster and higher than the static mode. The study of relaxation and fatigue behavior of the bandage helps in evaluating the bandage behavior during compression treatment.     

A feasibility study of the use of a SIRE biosensor in the monitoring of H2O2 added to milk samples. A possible new technology for early detection of mastitis?

Mastitic milk is known to degrade hydrogen peroxide at a higher rate than milk from healthy cows due to increased enzymatic, i.e. catalase, activity. This work deals with a feasibility study of a new method for monitoring hydrogen peroxide degradation in milk based on the electrochemical detection of hydrogen peroxide. This technology could be implemented in-line with the milking equipment at farms. A low pasteurised (75 °C/15 s), non-homogenised milk was chosen as a model for fresh milk. Milk samples were spiked with catalase (0.53–5.33 U/ml). Given that H₂O₂ as a parameter allows for the early indication of mastitis (in itself or in combination with other measurements), we believe that the SIRE technology could be developed further to meet the analytical requirements of such a detection system.