Inter-limb centre of pressure symmetry during gait among stroke survivors.

The purpose of the present study was to describe the spatial-temporal parameters of the centre of pressure (COP) trajectory during the single-support phase of gait among stroke survivors and relate these parameters to the severity of sensorimotor impairment. Fifty-seven participants were asked to walk at their preferred and fast speed over a pressure sensitive mat. Outcome measures included anterior-posterior (AP) COP displacement, AP-COP velocity, medial-lateral (ML) COP variability and foot region COP time. The results demonstrated an asymmetrical AP-COP displacement in favour of the non-paretic limb for the majority of participants. The inter-limb difference scores for AP-COP displacement and AP-COP velocity were related to the severity of sensorimotor impairment and greater among gait aid users. ML-COP variability was greater under the non-paretic limb, possibly suggesting difficulty with paretic limb swing phase. Reduced or absent forefoot COP time suggests difficulty with forward progression and modified foot function during push-off. The inter-limb difference in COP parameters highlights the asymmetrical nature of post-stroke gait and the challenge of maintaining single limb support. We view this information as potentially important to clinicians as an outcome measure for gait rehabilitation.