Study And Analysis Of Biomechanical Parameters Of Human Movement Based On Disability Indicators In Older Adults Through Multifactorial Analysis

Abstract

Introduction: Age-related decline and functional disability research present several challenges. Main objectives: To identify biomechanical determinants from various functional tasks that characterize the movement of community-dwelling older adults and to distinguish performance between those with and without functional disability. Methods: Two systematic reviews and one scoping review were conducted to: identify disability indicators, and respective assessment instruments (Study I); examine the application of principal component analysis in older adults' movement assessment (Study II); and gather guidelines for the kinematic assessment of older adults (Study III). Four cross-sectional studies assessed 60 community-dwelling older adults, with (n=25) and without (n=35) functional disability while performing gait (Study IV), stair negotiation and floor transitions (Study V), sit-to-stand and stand-to-sit transitions (Study VI), and the timed up and go (Study VII) using an optoelectronic system. Tridimensional lower limb joint positions and angular velocities, center of mass displacement and velocity, and other biomechanical variables were analyzed to develop principal component models. Results: Functional disability can be characterized by handgrip strength, balance, self-reported health status, basic and instrumental activities of daily living (Study I). Factor analysis has been applied to assess spatiotemporal gait parameters (Study II), and guidelines have been established for this assessment (Study III). Studies IV to VII identified key biomechanical domains defining older adults performance, emphasizing hip and knee control, temporal and variability measures, and trunk kinematics. Biomechanical differences between functional disability groups were observed in gait, stand-to-sit, timed up and go and stair negotiation at pace-related parameters, hip control, trunk kinematics and joint velocities. Conclusions: Older adults' biomechanical performance was characterized into domains, revealing structural relationships among variables that also differentiate functional disability.