The effect of weight-bearing pressure on the plantar circulation in diabetes mellitus.

Patients with diabetic neuropathy are prone to ulceration on the sole of the foot, especially in areas with high weight-bearing pressure. The relationship between weight-bearing pressure and nutritive skin circulation in the plantar region was studied. Gait analysis was performed with the EMED Gait Analysis System and the skin circulation was measured by fluorescein flowmetry in ten neuropathic diabetic patients and in eight healthy controls. The critical plantar foot pressure above which nutritional blood flow in the skin was arrested was 3 N cm-2 or more in both diabetic and control subjects. Below 3 N cm-2 the blood flow was independent of weight-bearing pressure both in diabetic and control subjects (correlation coefficient r = -0.01 and -0.19, respectively). Thus, our results indicate that the nutritional blood flow in the plantar region is not decreased in patients with diabetic neuropathy.