Perception of Weight-Bearing Distribution During Sit-to-Stand Tasks in Hemiparetic and Healthy Individuals

Abstract

Background and Purpose-It is unknown whether hemiparetic individuals are aware of their weight-bearing asymmetry during sit-to-stand tasks. This study compared the error between hemiparetic and healthy individuals' perception of weight-bearing and their actual weight-bearing distribution during the sit-to-stand task and analyzed the association between the knee extensor muscle strength and the weight-bearing distribution and perception. Methods-Nineteen unilateral hemiparetic subjects and 15 healthy individuals participated in the study. They performed the sit-to-stand transfer on force platforms under different foot placements (spontaneous and symmetrical) and had to rate their perceived weight-bearing distribution at the lower limbs on a visual analog scale. The strength of the knee extensors was assessed with a Biodex dynamometer. Results-The hemiparetic individuals presented greater weight-bearing asymmetry and errors of perception than the healthy individuals. Although no significant association was found between strength and weight-bearing perception, moderate associations were found between strength and weight-bearing distribution for both the spontaneous (rϭ0.75, PϽ0.01) and symmetrical (rϭ0.71, PϽ0.01) foot position conditions. Conclusions-This study revealed that individuals with hemiparesis after a stroke do not perceive themselves as asymmetrical when executing the sit-to-stand transfer and that the knee extensor strength is a factor linked to their weight-bearing asymmetry, not to their perception. (Stroke. 2010;41:1704-1708.)

Weight-Bearing and Effort Distributions at the Lower Limbs during the Five-Repetition Sit-to-Stand Test in Hemiparetic and Healthy Individuals

“…The WB distribution on each side, expressed in percent of total WB, was determined using the VGRF of the seat and foot averaged over a 1 s time interval (from −0.5 s before seat-off to 0.5 s after; details in Brière et al [8]). The seat-off corresponded to the time when the forces on the force plates of the seat were null.…”

“…Following the dynamometric assessment, a height-adjustable chair instrumented with force plates under each thigh was used to assess the STS tasks (details in Brière et al [8]). Two AMTI (OR6-7-1000) force plates were used to record the forces under each foot.…”

“…In both groups, Pearson correlation coefficients were used to assess the associations between time to execute the 5R-STS test and WB and effort distributions. Also, as previous studies [8,9] have already established that hemiparetic individuals perform more asymmetrically than healthy ones, and as the two groups here did not have the same number of subjects, the group effect was not considered in the further analyses. Therefore, three one-way repeated-measures ANOVAs tested the effect of consecutive STSs (repeated factor) on WB distribution, effort distribution, and time cycle, respectively, separately in each group.…”

“…Following a stroke, STS and stand-to-sit transfers are performed with an asymmetrical weight-bearing (WB) distribution with more weight usually taken by the nonparetic limb [8,9]. The knee extensor joint moments are also asymmetrical with greater moments produced by the nonparetic side [10].…”

Influence of Foot Position in the Performance of Sit to Stand in Post Stroke Hemiparetic Patients

“…(18) Evidence suggests that muscle strength (especially the concentric activity of the knee extensors and ankle extensor and flexor eccentric plantar) and the weight distribution skill in the paretic side are important factors in the ability of standing up.…”