Coordination Variability During Walking and Running in Individuals With and Without Patellofemoral Pain Part 2: Proximal Segments Coordination Variability

Abstract

Although it has been proposed\xa0that individuals with patellofemoral pain show less lower limb intersegmental coordination variability, the evidence to support this hypothesis is rare. The purpose of this study was, therefore, to evaluate whether individuals with patellofemoral pain exhibit less intersegmental coordination variability compared with healthy individuals during walking and running. Also, it was hypothesized that increasing task demand would exacerbate group differences regarding coordination variability measures. Three-dimensional kinematics were collected while 17 females with patellofemoral pain and 17 healthy females walked at preferred speed, and ran at preferred and\xa0fixed speed on a treadmill, each trial\xa0for 30 seconds. An approach involving Hilbert transform was used to quantify the Continuous Relative Phase as a method to calculate the coordination variability of the thigh-shank and shank-foot couplings in different motion planes during stance and swing. Intersegmental coordination variability was compared between groups during 3 gait trials using a mixed-model repeated-measures ANOVA. The patellofemoral pain group was significantly less variable compared with the control group in the following couplings: thigh sagittal-shank transverse, thigh transverse-shank transverse, shank transverse-foot sagittal, shank sagittal-foot transverse at both running speeds, thigh frontal-shank transverse at preferred speed running, and shank transverse-foot transverse at fixed speed running, all during stance phase. No between-group difference was observed during walking. Only the patellofemoral pain group showed changes in coordination variability by increasing task demand, in a way that they showed less coordination variability at running trials compared with the walking and also at fixed speed compared with the preferred speed running for some of the examined couplings. Based on the results, less lower limb intersegmental coordination variability may be characteristic of females with patellofemoral pain during treadmill running. Increasing task demand from walking to running and also from preferred speed to fixed speed running which mainly resulted from increasing gait speed could exacerbate this altered coordination variability.