A method for measuring the dynamic behavior of medical compression hosiery during walking

BACKGROUND. Compression therapy is effective in patients suffering from venous disease. This therapy has proven to be especially effective in the ambulant patient. Therefore, the dynamic behavior of the medical compression hosiery (MCH) is more important than the static one in the treatment of patients. OBJECTIVE. The objective of this study was to develop a method for investigating the dynamic behavior of MCH during walking. METHODS. The changes in the circumference of the lower leg equipped with a MCH are registered on a treadmill. The dynamic movement is then exactly simulated using an artificial leg-segment model equipped with the same MCH. The dynamic behavior of the MCH can thus be investigated using this artificial leg-segment model. The dynamic stiffness index can be calculated from the dynamic pressure and circumference signals. RESULTS. The expansion of the MCH was only limited to the area underlying the expanding muscles and did not spread circularly. This resulted in relatively high pressure exerted by the MCH on the underlying tissues during walking. Insertion of nonelastic material into the MCH overlying the expanding muscles increased the dynamic pressure. CONCLUSIONS. The active behavior of the MCH during normal walking differed considerably from its passive behavior. We defined a new characteristic of the MCH: the dynamic stiffness index based on the dynamic pressure profile. Insertion of nonelastic materials into the MCH covering overlying the expanding muscles increased the dynamic stiffness index.