Weight-bearing perception during standing and sit-to-stand tasks in subacute post-stroke individuals undergoing intensive rehabilitation.

OBJECTIVE: It is well known that people with hemiparesis after stroke have asymmetric weight bearing (WB) when standing and during sit-to-stand (STS). However, few studies have quantified the WB perception during these tasks in rehabilitation, which might be an important consideration for therapists. This study assessed WB errors in perception during rehabilitation in subacute post-stroke individuals and identified factors that might explain greater errors in WB perception.

MATERIAL/PATIENTS AND METHODS: Sixteen participants (9 right lesions; 52.6 [±23] days post-stroke) admitted in a stroke unit agreed to participate. The first assessment (admission) was performed when they could stand alone 10 s and rise from sitting, and the second (discharge) a week before discharge. Their physical therapist performed the clinical tests. They were then assessed in the laboratory with force plates to characterize their WB distributions during three trials of standing and STS tasks using two-foot positions (spontaneous and standardised). They were also asked to rate their perceived WB distribution at the lower limbs on a visual analog scale. Multivariate and correlational analyses allowed comparison of real WB and WB perception while standing and rising at admission and discharge, and identification of factors that might influence the errors in WB perception.

RESULTS: WB asymmetry was present in the first months after stroke and persisted despite rehabilitation. Overall, WB asymmetry at admission and discharge were not different. The patients were able to identify the side on which the loading was higher but tended to overestimate the WB under the paretic foot. There were no effects of tasks, time of evaluation or foot position on the errors of WB perception. At admission, the mean values of absolute error were 8.23% (7.10) and 8.38% (6.24) for the spontaneous standing and STS tasks, respectively. Paretic lower limb motor function evaluated by Chedoke, and knee extensor strength were associated with errors in WB perception.

DISCUSSION - CONCLUSION: Therapists could not consider that WB perception is precise in subacute post-stroke individuals. It would be interesting in the future to further explore the size or the threshold of error in WB perception that has an effect on rehabilitation.