Diabetic Feet at Risk of Plantar Ulcers: a New Method of Analysis of Standing Foot Pressure Images with Variations in Foot Sole Properties

The most feared lower extremity problem among patients with diabetes is amputation, and the sequences of events leading to amputation are initiated by skin ulceration combined with sensation loss (Birke, J.A. et.al.1995). Therefore, it is essential to detect the foot at risk of plantar ulceration, at an early stage of sensation loss, so as to prevent complications and amputation, (Armstrong, D.G. et.al 1998). It is found that the foot pressure parameters are functions of the mechanical properties of foot sole soft tissue and also different levels of sensation loss. Therefore, this paper presents the results of the research study undertaken to find the relationship between the foot pressures characterized by a new parameter known as Power Ratio, PR (the ratio of high frequency power to the total power in the power spectrum of the foot pressure image) at different levels of sensation loss and the foot sole mechanical property (in terms of hardness of foot sole soft tissue characterized by its Shore level, Sh).