Modeling the mechanics of a medical compression stocking through its components behavior: Part 1 – modeling at the yarn scale

Abstract

The goal of this article is to propose practical and scientific explanations about the mechanics of compression by the medical compression stocking (MCS) to the phlebologist and angiologist societies. The first part presents the principle of pressure generated by the MCS. We explain how the surface of MCS fabric is structured from the yarn scale and how each component of the yarn contributes to generate the desired compression. The second part is dedicated to the mechanical behavior modeling of the covered yarn, which is the main yarn component of the elastic knitted fabric of the MCS. The structure analysis shows that the properties of the inlaid yarns reflect significantly the global behavior of the fabric. Therefore, by characterizing the elastic properties of the inlaid yarn, it is possible to predict the mechanical behavior of the entire MCS fabric. We suggest a few approaches to model the covered elastic yarns used in different types of products. The third part describes an identification procedure aiming to calculate the unknown parameters of the mathematical models with the yarn elongation curves. The principle is to divide the general model into several sub-models in order to avoid considering simultaneously a great number of parameters in the identification procedure. The last part presents a set of identification results that compare measured values with simulated data. With a reliable model of the elastic yarns, an efficient strategy can be conducted to define the proper inlaid yarn (for the MCS construction), aiming to treat efficiently vein diseases at different stages according to medical prescription and the patient’s need.

Prediction of Compression of Knitted Orthopaedic Supports by Inlay-Yarn Properties

“…The results demonstrate that by increasing the number of tested threads, the elongation value has a higher impact on tensile force. The compression level is directly in relation with pressure P [7]. The physical definition of pressure is :…”

Compression Garments for Medical Therapy and Sports

“…An analysis based on the elastomeric yarn wrapped with nylon will explain elongation performance. Figure 1 shows the theory of the superposition of two yarn models including elastomeric and plastic yarns in the elongation dynamics and they all contribute to the general model with the continuous purple curve [69]. From the beginning to ε 0 , the strain is mainly acquired from the elastomeric yarn with high elastic modulus, as shown by the red dashed curve.…”

In Vivo Measurement of the Friction Between Human Skin and Different Medical Compression Stockings

“…Medical compression stockings are known to be different from normal socks [17]. They include two components which are normally made of different materials: a layer of inlaid yarns and a layer of knitted loops.…”