Foot progression angle and medial loading in individuals with diabetes mellitus, peripheral neuropathy, and a foot ulcer

Foot progression angle (FPA) and duration of foot medial column loading during walking were studied in individuals with diabetes mellitus (DM), peripheral neuropathy (PN), and a forefoot ulcer (DMPN), and in age-matched control subjects. FPA was calculated from EMED-ST P-2 pressure maps as the angle formed between the longitudinal axis of the foot and the forward line of progression during walking. The medial loading duration was calculated as the amount of time the center of pressure line spent in the medial side of the foot pressure map. FPA was increased in the DMPN group, on the involved and uninvolved sides [15(9)° and 13(4)° respectively] compared the control group [9(4)°]. FPA and medial loading duration were significantly correlated in the DMPN group on the involved and uninvolved sides (r > 0.54, p < 0.036), but were not significantly correlated in the control group (r < |0.07|, p > 0.82). This study provides evidence that FPA is an important biomechanical contributor to the pattern of foot loading in individuals with DM, PN, and a forefoot ulcer.