Fourier analysis of vertical ground reaction forces distinguishes gait patterns in hip, knee, and ankle osteoarthritis

Abstract

Purpose: Osteoarthritis (OA) of the hip, knee, and ankle are prevalent diseases associated with pain and impaired function. Gait changes in OA include altered walking speeds, stance time, step time, step length, and stride length. Vertical ground reaction force (VGRF) curves reflect spring mechanics of the leg while the lower extremity interacts with the ground. In normal conditions, the VGRF is a bimodal curve wherein two maxima are separated by a local minimum near midstance. Previous studies of VGRFs in participants with OA have demonstrated reduced peak forces in OA compared to control participants; there were significant differences between hip (HOA) and knee OA (KOA) as well as HOA and ankle OA (AOA); however, there were no statistically significant differences between the KOA and AOA participants.