The impact of foot position on sit-to-stand stability and lower limb loading in hemiplegic stroke patients

Abstract

Objective To explore the effects of different foot positions on lower limb loading and the sit- to-stand stability of hemiplegic stroke patients. Methods Thirty-six hemiplegic stroke patients were recruited as the experimental group and 36 healthy elderly as the control group. Both groups of subjects completed sit-to-stand movements with 3 different foot positions： （ 1 ） both feet （BF） placed at 10° of ankle dorsiflexion; （2） the paretic foot placed posterior （PFP） for hemiparetic subjects or the undominant foot placed posterior （UDFP） for healthy subjects; （3） the non-paretic foot placed posterior （NPFP） for hemiparetic subjects or the dominant foot placed posterior （DFP） for healthy subjects. The time required to rise from sitting, the average load difference （ALD） be- tween the left and right feet and sway of the center of gravity in the mediolateral direction （COGX） were measured. Results Comparing BF with PFP positioning, the time to rise was not significantly different but the loads on the two legs, the ALD and the COGX in were all significantly different. Comparing NPFP with PFP positioning, all the indexes were significantly different, and the time to rise was significantly different from the BF positioning. For the control group, all the indexes significantly different in the BP and PFP positions, and the time to rise was signifi- cantly different from that required with the UDFP placement. In all 3 foot positions, all of the experimental group＇ s indices differed significantly from those of the control group. In both groups there was a strong positive correlation between the average ALD and COGX values in all three foot positions. Conclusions Foot placement influences lower limb loading and stability in rising from sitting for hemiplegic stroke survivors. The greater the symmetry of lower limb loading, the better the postural stability. Key words: Stroke ; Hemiplegia; Sit-to-stand ; Posture ; Lower limb loading