Investigation of the Pressure Transmission Characteristics of Miniaturised Air Bladders for Medical Compression Textiles

Compression therapy is considered as the cornerstone of treatment for all types of Chronic Venous Disease (CVD), which is the most prevalent vascular disease affecting the lower extremities. However, most of the existing medical compression textiles inherit a limitation of applying uniform pressure around the lower limb circumference. Previous research has shown that this limitation could be overcome by applying a radial force due to a pressure exerted by an air volume trapped inside a miniature bladder. Thus, this study analysed the pressure transmission characteristics of the miniature bladders via numerical modelling and laboratory experiments. The pressure transmission characteristics of miniaturised air bladders and the percentage of the area, where uniform pressure is applied were investigated for a variety of size and thickness parameters using numerical simulations. It was observed that the percentage of pressure transmission increased as the bladder size decreased while it increased as the thickness increased. Moreover, the percentage of area where the pressure is applied has a positive correlation with the bladder size while a negative correlation existed with its thickness. The experimental findings of this study further revealed that around 55% of the applied pressure into the miniaturised bladder was transmitted on a hard surface. Both experimental results and numerical simulations displayed similar results where the average interface pressure of the simulations had more than 95% agreement with the experimental pressure values obtained.