Interactions between foot placement, trunk frontal position, weight-bearing and knee moment asymmetry at seat-off during rising from a chair in healthy controls and persons with hemiparesis.
OBJECTIVE
To assess the interaction of foot placement, trunk frontal position, weight-bearing and knee moment asymmetry at seat-off when rising from a chair.


METHODS
Cross-sectional study.


METHODS
Seventeen subjects with hemiparesis and 15 healthy controls.


METHODS
Trunk position, weight-bearing and knee moment asymmetry were quantified by kinetic and kinematic analysis when the subjects rose from a chair using 3 different foot placements: spontaneous, symmetrical and asymmetrical. Asymmetry was defined by the ratio between sides.


RESULTS
In the healthy controls, the spontaneous and symmetrical foot placements were associated with an almost vertical trunk position and a symmetrical weight-bearing and knee moment. The asymmetrical foot placement resulted in a trunk displacement towards the foot placed behind, with more weight-bearing and higher moment on this side. The opposite was observed in the hemiparetic participants where the spontaneous and symmetrical foot conditions determined a trunk position and an asymmetry bias towards the unaffected side. Placing the affected foot behind the other reduced the asymmetrical behaviour.


CONCLUSIONS
Changes in weight-bearing are partly associated with the frontal trunk position, and foot placement manipulations can be used to modify weight-bearing distribution. Inference on weight-bearing is possible by observing the trunk position during the sit-to-stand task in persons with hemiparesis.
Lecours
Julie
J
Centre de recherche interdisciplinaire en réadaptation, Institut de réadaptation de Montréal, Canada.
Nadeau
Sylvie
S
Gravel
Denis
D
Teixera-Salmela
Luci
L
D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D005528:Foot; D006429:Hemiplegia / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D007717:Knee; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology; D000071939:Stroke Rehabilitation; D016474:Weight-Bearing / Q000502:physiology