Effects of Dual-task Performance on Postural Sway of Stroke Patients with Experience of Falls

Fallers after stroke: a retrospective study to investigate the combination of postural sway measures and clinical information in faller's identification

Background

Falls can have devastating effects on quality of life. No clear relationships have been identified between clinical and stabilometric postural measures and falling in persons after stroke.

Objective

This cross-sectional study investigates the value of including stabilometric measures of sway with clinical measures of balance in models for identification of faller chronic stroke survivors, and the relations between variables.

Methods

Clinical and stabilometric data were collected from a convenience sample of 49 persons with stroke in hospital care. They were categorized as fallers (N = 21) or non-fallers (N = 28) based on the occurrence of falls in the previous 6 months. Logistic regression (model 1) was performed with clinical measures, including the Berg Balance scale (BBS), Barthel Index (BI), and Dynamic Gait Index (DGI). A second model (model 2) was run with stabilometric measures, including mediolateral (SwayML) and anterior-posterior sway (SwayAP), velocity of antero-posterior (VelAP) and medio-lateral sway (VelML), and absolute position of center of pressure (CopX abs). A third stepwise regression model was run including all variables, resulting in a model with SwayML, BBS, and BI (model 3). Finally, correlations between independent variables were analyzed.

Results

The area under the curve (AUC) for model 1 was 0.68 (95%CI: 0.53-0.83, sensitivity = 95%, specificity = 39%) with prediction accuracy of 63.3%. Model 2 resulted in an AUC of 0.68 (95%CI: 0.53-0.84, sensitivity = 76%, specificity = 57%) with prediction accuracy of 65.3%. The AUC of stepwise model 3 was 0.74 (95%CI: 0.60-0.88, sensitivity = 57%, specificity = 81%) with prediction accuracy of 67.4%. Finally, statistically significant correlations were found between clinical variables (p < 0.05), only velocity parameters were correlated with balance performance (p < 0.05).

Conclusion

A model combining BBS, BI, and SwayML was best at identifying faller status in persons in the chronic phase post stroke. When balance performance is poor, a high SwayML may be part of a strategy protecting from falls.

The correlation between muscle activity of the quadriceps and balance and gait in stroke patients

[Purpose] The purpose of this study was to examine the correlation between quadriceps muscle activity and balance and gait in stroke patients. [Subjects and Methods] Fifty-five stroke patients (30 males 25 females; mean age 58.7 years; stroke duration 4.82 months; Korean mini-mental state examination score 26.4) participated in this study. MP100 surface electromyography, BioRescue, and LUKOtronic were used to measure the quadriceps muscle activity, balance, and gait, respectively. [Results] There was a significant correlation between quadriceps muscle activity (vastus lateralis % reference voluntary contraction, vastus medialis % reference voluntary contraction) and balance (limits of stability) and gait (gait velocity) but there was none between vastus lateralis % reference voluntary contraction, vastus medialis % reference voluntary contraction. [Conclusion] An increase in quadriceps muscle activity will improve balance and gait ability. To improve function in stroke patients, training is needed to strengthen the quadriceps muscles.

The effect of virtual reality-based eccentric training on lower extremity muscle activation and balance in stroke patients

[Purpose] The purpose of this study was to examine the effect of virtual reality-based eccentric training on lower extremity muscle activity and balance in stroke patients. [Subjects and Methods] Thirty stroke patients participated, with 15 patients allotted to each of two eccentric training groups: one using a slow velocity (group I) and one using a fast velocity (group II). The virtual reality-based eccentric training was performed by the patients for 30 minutes once a day, 5 days a week, for 8 weeks using an Eccentron system. Surface electromyography was used to measure the lower extremity muscle activity, while a BioRescue was used to measure balancing ability. [Results] A significant difference in lower extremity muscle activation and balance ability was observed in group I compared with group II. [Conclusion] This study showed that virtual reality-based eccentric training using a slow velocity is effective for improving lower extremity muscle activity and balance in stroke patients.

Effect of dual-task training on postural stability in children with infantile hemiparesis

[Purpose] The aim of this study was to evaluate the influence of using a selected dual-task training program to improve postural stability in infantile hemiparesis. [Subjects and Methods] Thirty patients participated in this study; patients were classified randomly into two equal groups: study and control groups. Both groups received conventional physical therapy treatment including mobility exercises, balance exercises, gait training exercises, and exercises to improve physical conditioning. In addition, the study group received a selected dual-task training program including balance and cognitive activities. The treatment program was conducted thrice per week for six successive weeks. The patients were assessed with the Biodex Balance System. These measures were recorded two times: before the application of the treatment program (pre) and after the end of the treatment program (post). [Results] There was a significant improvement for both groups; the improvement was significantly higher in the study group compared to the control group. [Conclusion] The selected dual-task training program is effective in improving postural stability in patients with infantile hemiparesis when added to the conventional physical therapy program.

The effects of multidirectional stepping training on balance, gait ability, and falls efficacy following stroke

[Purpose] The purpose of this study was to determine whether a multidirectional stepping training improves balance, gait ability, and falls efficacy in stroke patients. [Subjects] Firty patients who met the selection criteria and agreed to participate in research at hospital N were randomly allocated and enrolled in this study. Twenty of the subjects were assigned to an experimental group that participated in combined stepping exercise, and the other twenty subjects were assigned to a control group that received general physical therapy. [Methods] In the two groups, balance was measured using the Berg Balance Scale, gait ability was measured using the 10-m Walk Test, and falls efficacy was measured using the Falls Efficacy Scale before training and after 6 weeks of training. [Results] Comparative analysis of the experimental group’s pretest and post-test results showed statistically significant differences in the Berg Balance Scale, 10-m Walk Test, and Falls Efficacy Scale scores. There were significant between-group differences in the Berg Balance Scale, 10-m Walk Test, and Falls Efficacy Scale scores. [Conclusion] The results suggest that a combined stepping exercise can be an effective intervention to improve the balance, gait ability, and falls efficacy in stroke patients.

Risk factors related to falling in stroke patients: a cross-sectional study

[Purpose] The purpose of this study was to investigate a comprehensive understanding of the factors associated with falls in poststroke patients. [Subjects] Forty-eight stroke patients (22 males and 26 females; age 63.79 years) participated in this study. [Methods] This study applied a cross-sectional design. Fear of falling [Falls Efficacy Scale (FES)], balance function [Berg Balance Scale (BBS) and Modified Rivermead Mobility Index (MRMI)], ADL performance level [Modified Barthel Index (MBI)] and cognitive function [Loewenstein Occupational Therapy Cognitive Assessment for Geriatric Populations (LOTCA-G)] were assessed. [Results] Falls efficacy was moderately correlated with ADL performance, balance, and cognition. In addition, stepwise linear regression analysis revealed that ADL performance was the explanatory variable closely associated with falls efficacy in stroke patients. [Conclusion] ADL performance was the primary explanatory variable of falls efficacy according to regression analysis. Thus, we suggest that these results may be used as basic data for developing rehabilitation programs for prevention of falls in stroke patients.

Effects of auditory feedback during gait training on hemiplegic patients' weight bearing and dynamic balance ability

[Purpose] This study examined the effects of auditory feedback during gait on the weight bearing of patients with hemiplegia resulting from a stroke. [Subjects] Thirty hemiplegic patients participated in this experiment and they were randomly allocated to an experimental group and a control group. [Methods] Both groups received neuro-developmental treatment for four weeks and the experimental group additionally received auditory feedback during gait training. In order to examine auditory feedback effects on weight bearing during gait, a motion analysis system GAITRite was used to measure the duration of the stance phase and single limb stance phase of the subjects. [Results] The experimental group showed statistically significant improvements in the duration of the stance phase and single limb stance phase of the paretic side and the results of the Timed Up and Go Test after the training. [Conclusion] Auditory feedback during gait training significantly improved the duration of the stance phase and single limb stance phase of hemiplegic stroke patients.

Relationship between Postural Sway and Dynamic Balance in Stroke Patients

[Purpose] The purpose of the current study was to investigate the relationship between postural sway and dynamic balance in post stroke patients. [Subjects] Thirty-one stroke patients (20 men and 11 women; age 64.25 years; stroke duration 12.70 months; MMSE-K score 26.35) participated in this study. [Methods] This study applied a cross-sectional design. A Good Balance system was used for measurement of the postural sway velocity (anteroposterior and mediolateral) and velocity moment of subjects under the eyes open and eyes closed conditions in a standing posture. The postural sway of subjects was measured under two surface conditions (stable and unstable surfaces). [Results] On the unstable surface (foam), no significant correlation was observed between postural sway and dynamic balance except for the berg balance scale (BBS) score and anteroposterior postural sway velocity under the eyes open condition, anteroposterior postural sway velocity under the eyes closed condition, and postural sway velocity moment. In addition, in the stable condition, no significant correlation was observed between postural sway and dynamic balance. [Conclusion] Our results indicate that a decrease in postural sway does not necessarily reflect improvement of dynamic balance ability. We believe that this finding may be useful in balance rehabilitation for prevention of falls after a stroke.

Recovery process of standing postural control in hemiplegia after stroke

[Purpose] The aim of this study was to investigate the recovery process of standing postural control in hemiplegia after stroke. [Subjects and Methods] Thirty-four inpatients with hemiparesis after first-onset stroke were included in this study. We measured the center of pressure fluctuations during quiet standing using a force platform at 2, 4, and 6 weeks after admission. We assessed weight-bearing asymmetry, and velocity and amplitude of body sway. [Results] Weight-bearing asymmetry diminished in the first 2 weeks of observation. Velocity of body sway also decreased significantly in the first 2 weeks, though its amplitude only decreased significantly after 4 weeks of observation. [Conclusion] Amplitude of body sway requires a longer time for significant improvement than weight-bearing asymmetry and velocity of body sway. Although the loading function of the paretic lower limb improved at an early stage, attainment of optimum postural control, including management of the affected paretic lower limb, requires much time.