Relationship between peripheral vascular disease and high plantar pressures in diabetic neuro-ischaemic patients

It has been shown that high foot pressure in diabetic patients plays a crucial role in plantar ulcer development. The purpose of the study is to analyze the relationship between foot arterial pressures and plantar pressures in diabetic patients with both peripheral neuropathy vascular disease.

We have evaluated the relationship between foot arterial pressures and plantar pressure parameters (Peak Plantar Pressure, Foot-Floor Contact and Plantar Pressure Integral) in eleven diabetic patients with both peripheral neuropathy and peripheral vascular disease. Peripheral neuropathy was defined as a tuning fork score<4/8 measured at the great toe and internal malleolus with a Tuning fork (Rydel-Seiffer 128 Hz), the absence of both patellar and ankle reflexes and with a temperature discrimination more than +5 degrees C (Thermocross). The peripheral vascular disease (PVD) was evaluated by Doppler technique. Peak Plantar Pressure (PPP) and Foot-Floor Contact (FFC) were measured by Force-Sensing Resistive (FSR 174) sensors under the 1st, 3rd and 5th metatarsal heads as well as under the heel and big toe of both feet. The Plantar Pressure Integral (PPI) was defined by the integral of the pressure over the time.

We have found significant relationship between plantar pressure parameters (PPP, FFC, and PPI) under the first metatarsal heads and Doppler arterial pressures of both tibial posterior and dorsalis pedis artery. However, there was no relationship between Doppler arterial pressures and plantar pressure parameters (PPP, FFC, PPI) under 3rd and 5th metatarsal heads or under both the heel and the big toe.

According to our results, the peripheral vascular disease could contribute to the elevation of plantar pressures and to the prolonged duration of foot floor contact at each step in diabetic patients with both peripheral neuropathy and peripheral vascular disease. In such patients, severe ischaemia could lead to an increased risk of foot ulceration and consecutive lower extremity amputation.