Efficacy of using the pelvic method to estimate centre of mass position in response to gait perturbations

During gait the centre of mass (COM) should be maintained relative to the base of support for optimal efficiency of movement, and reduced risk of falling. The ability to control the COM position is challenged for every step, and is therefore an important tool in clinical practice to predict dynamic stability. To ensure accuracy and precision of COM estimation, motion analysis equipment and full body (FB) tracking is required. Difficulty implementing this due to time and expertise limitations causes clinicians to favour the pelvic model (P), assuming the COM can be represented by the centre point of the pelvis. This may trade accuracy and precision for clinical applicability. The aim of this study was to investigate COM representation during unperturbed and perturbed gait using a reduced kinematic model.