Improving repeatability of setting volume origin and coordinate system for 3D gait analysis

Abstract

This study investigated the variability arising from replacement of different calibration objects. A new calibration object (L-Frame) was instigated which consisted of four markers screwed into fixed positions in the floor, to ensure consistency between replacements. The variability of a healthy subject's joint moments from replacement of different calibration objects (5 marker wand and L-Frame) was compared to the subject's stride-to-stride repeatability (SSR). Overall the L-Frame calibration object demonstrated the least amount of variation during object replacement for both sagittal and coronal joint moments. In particular for the coronal ankle moment the 5 marker wand positioned at the e..