Skin Temperature Perception and Prosthetic Thermoregulation

This study will include four groups of participants including individuals with diabetes, individuals without a diagnosis of diabetes, individuals with lower limb amputations of diabetic etiology, and individuals with lower limb amputations of non-diabetic etiologies. To measure temperature perception, a thermode (a temperature changing device about the size of a coffee cup) will be placed on the lower leg of each participant. The thermode also included a laser Doppler flow meter, embedded in the center of the thermode, to measure blood flow in response to changes in skin temperature. The experimental protocol begins with the thermode set for 3 minutes at 30 °C, 32 °C, 34 °C, and 35 °C (random order). The temperature will then be either increased or decreased at a slow rate of 0.2 °C/sec until the participant perceives either a warming or cooling sensation. The analysis plan includes determining the threshold at which a temperature change was perceived relative to each initial temperature, whether there are differences in blood flow (vascular reactivity) when thermal stimuli are detected, and these measurements are altered by diabetes or amputation. The general hypotheses are that these populations will have (1) different warm and cool temperature perception thresholds depending on the initial skin temperature and (2) different changes in skin blood flow as a function of their temperature perception thresholds.