Predictability of Pressure Characterization of Medical Compression Stockings (MCSs) Directly Based on Knitting Parameters

Abstract

Medical compression stockings (MCSs) is one of the most important medical devices for compression therapy. Pressure profile (pressure magnitude and compression gradient) exerted on patient’s lower limb is the key to an effective treatment for Chronic venous disease (CVD). The present study was conducted to engineer the knitting parameters technically to match directly pressure requirements. Initially, totally 81 types of compression tubes (Class I, II & III) for three main regions (ankle, calf, & thigh) were produced at machine settings based on orthogonal optimization of knitting parameters (PYF feeder speed, position of needle cylinder, knitting cam for ground stiches, and knitting cam for laid-in stiches). Furthermore, the fundamental relationship between the knitting parameters and pressure characterization of compression tubes was derived by multiple regression analysis. The derived equation had a good regression coefficient (R12=0.681) for Class Ι compression tubes, and lower regression coefficient (R22=0.360, R32=0.311) for Class II & III compression tubes. Finally, compression stockings (Class I, II & III) were technically knitted for varied girths of rigid legmodels, the pressure differences that measured pressure values with predicted data were within ±4 mmHg for most of the developed MCSs.