An Investigation of Two Methods for Quantifying Inter and Intra-Limb Control/Co-ordination Processes of Gait

This paper examines two methods of measuring pattern dynamics for characterising the inter- and intra- limb processes underlying gait control/coordination. A sample of eighteen subjects completed a twenty-minute treadmill test. Minimum foot clearance values were taken at successive bilateral events. Using detrended fluctuation\ud analysis, we computed α (self-similarity\ud parameter), a measure of the degree to which a\ud single value in a series of data is correlated with a\ud previous and subsequent value over different time\ud scales. Also, a ratio value ψ, provides a measure of the short term variability relative to long term variability obtained from the Poincaré plot. The two methods demonstrate a correlation between α and ψ for both intra-limb (r = -0.59) and interlimb processes (r = -0.64). Both methods indicate \ud correlations existing within the control processes of intra- and inter-limb MFC events