[Towards a better understanding and quantitative assessment of pushing, a postural behaviour caused by some strokes].
BACKGROUND
Postural control aims to build up and align the body orientation (posture) and stabilize body segments. The existence of two separate mechanisms, one for the control of body orientation with respect to gravity and one for its stabilisation, is an emerging concept that allows a better understanding of postural disorders, including pushing, after stroke. Objectives. - Literature review concerning pushing, one of the most puzzling postural behaviours after stroke.


METHODS
Critical review of papers indexed in Medline and book chapters dealing with pushing.


RESULTS
There is no agreement about the definition of pushing: some authors consider that pushers push himself toward the paretic side using the healthy arm or leg; others consider that pushers lean (list) toward the side opposite the lesion and resist any attempt to become more upright. Surprisingly, the push itself has never been measured. Some ordinal scales have been recently proposed, but their psychometric properties have not been analysed. These methodological insufficiencies explain in part the disagreements about frequency (from 5% to 50% of patients with stroke) and cause(s) of pushing.


CONCLUSIONS
Pushing may be the most dramatic clinical manifestations of an extreme bias in the construction of the biological vertical. We argue for a better assessment of vertical perception/representation after stroke involving the three modalities of the biological (subjective) vertical: the visual vertical, the haptic or tactile vertical, and especially the postural vertical.
Pérennou
D
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Service de rééducation neurologique et Inserm ERM 207, centre de médecine physique et réadaptation, CHU de Dijon, France. dominic.perennou@chu-dijon.fr
D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D011187:Posture / Q000502:physiology*; D011434:Proprioception / Q000502:physiology; D020521:Stroke / Q000503:physiopathology*