Evaluation of Plantar Foot Sensation, Balance, Physical Performance, and Fear of Movement in Substance Use Disorders

Perfusion, Stance and Plantar Pressure Asymmetries on the Human Foot in the Absence of Disease—A Pilot Study

Physiological perfusion asymmetries in the lower limb are known, although poorly understood, as are asymmetries reported in plantar pressure and stance. This preliminary study aims to explore potential relationships between perfusion and pressure variables in humans. A convenience sample of eight healthy individuals (25.25 ± 5.37 years old) of both sexes, was selected. Chosen variables were perfusion, plantar pressure, and stance. Perfusion was measured in both feet by laser Doppler flowmetry (LDF) and polarized light spectroscopy (PSp), and plantar pressure and stance obtained by a pressure plate. These were measured in baseline (Phase I) in a repeated squatting (Phase II), and in recovery (Phase III). A 95% confidence interval was adopted. Intraindividual significant perfusion asymmetries between both feet were detected by LDF in Phase I. These disappeared in Phase II and returned in Phase III. PSp did not detect any asymmetries. Plantar pressure was also asymmetric and differently distributed along both feet with no statistical significance except in the hindfoot. Significant correlations were found between BMI and mean Plantar Pressure in Phase I and Phase III, and an inverse correlation between LDF perfusion and Plantar Pressure in Phase I. These results seem to suggest an interesting direction for exploration and study of these asymmetries in the absence of disease.