Comparison between an accelerometer and a three dimensional motion analysis system for estimating the vertical displacement of center of mass

Abstract

Background: The vertical displacement of center of mass (CoM) is related to walking efficiency, and is an important parameter to assess gait disorder. There are several methods to estimate CoM, for example, by using a force plate or a three-dimensional motion analysis system. However, these equipment are time-consuming, costly, limited to a single gait cycle, and restricted to a laboratory environment. One possible alternative to laboratory equipment is gait analysis by means of an accelerometer. This method permits a natural walking pattern over many repeated cycles. There have been previous studies comparing between accelerometer method and gold standard (e.g., force plate method and body segmental analysis method) for estimating the vertical displacement CoM at a comfortable walking speed, which show excellent relationship between the two methods, but little is known about the influence of walking speed.