Interpreting Spatiotemporal Parameters, Symmetry, and Variability in Clinical Gait Analysis

Abstract

Spatiotemporal parameters (STP) are widely studied variables in clinical gait analysis. Yet they often remain underutilized despite the rich information they provide about organization and control of the patient's progress. Building on them requires a broad knowledge of the "normal" gait, before to being able to understand the impact of pathological disorders. We hope to provide information to better grasp and understand the STP while highlighting important points. Through this chapter, we will introduce basics of the gait cycle, before considering the components for which the STP may be informative: rhythm, pace, phases, postural control, asymmetry, and variability. We will define main parameters for each component and discuss their use regarding state of the art. Then factors influencing STP will be addressed to understand how these parameters change during life, when a child learns to walk or when the advance in age-affected gait in the elderly, as well as the influence of diseases. Indeed, various pathologies affect the walk, and the most relevant STP are not always the same. We will consider Friedreich ataxia, which is a neurodegenerative disease, in which combination of cerebellar, pyramidal syndromes, and axonal neuropathy cause a rapid degeneration of the walking ability and therefore lead to various observable gait patterns. We will also illustrate how PST can be useful to 1 document the most appropriate time for a patient to change from one assistive device to another. The final portion will aim to give paths for clinical interpretation while thinking about the concepts of limitation and adaptation.