Investigating the effects of visual biofeedback therapy on recovery of postural balance in stroke patients using a complexity measure

The Application of Biological Feedback in the Rehabilitation of Patients after Ischemic Stroke

Balance disorders are the main concern for patients after an ischemic stroke. They are caused by an abnormal force on the affected side or paresis, which causes uneven loading and visuospatial disorders. Minimizing the effects of stroke is possible through properly conducted rehabilitation. One of the known ways to achieve this objective is biological feedback. The lack of proper muscle tone on one side of the body is manifested by the uneven pressure of the lower extremities on the ground. The study and control groups were composed of two equal groups of 92 people each, in which the same set of kinesiotherapeutic exercises were applied. Patients in the study group, in addition to standard medical procedures, exercised five days a week on a Balance Trainer for four weeks. The examination and training with the device were recorded on the first day of rehabilitation, as well as after two and four weeks of training. The assessment was performed using the following functional tests and scales: Brunnström, Rankin, Barthel, Ashworth, and VAS. Patients in the control group started exercising on the Balance Trainer two weeks after the first day of rehabilitation using traditional methods. The study results reveal statistically significant reductions in the time the body’s center of gravity (COG) spent in the tacks, outside the tracks and in the COG distance, lower COG excursions in all directions. Post-stroke patients that received biofeedback training presented significantly better results than patients that did not receive such training.

THE EFFECTS OF TRAINING ON DIFFERENT SURFACES, ON BALANCE AND GAIT PERFORMANCE IN STROKE HEMIPLEGIA

ABSTRACT Although many studies have focused on balance exercises for elderly or stroke patients, no comprehensive studies have investigated the use of training on different surfaces (TDS) with analysis of gait performance in elderly male stroke patients. The active properties of balance and subjective reporting of functional gait ability were used to identify the effects of TDS. Static balance (SB), dynamic balance (DB) and gait analysis was measured in 30 elderly stroke patients. The patients were divided into the TDS group (n=15) and a control group (CG, n=15). Fifteen elderly stroke patients underwent TDS five times a week for 12 weeks. The data was analyzed using repeated measures analysis of variance. Significant differences were observed between the two groups (TDS and Control): SB (p < 0.0001), DB (OSI: p < 0.0001, APSI: p < 0.001, MLSI: p < 0.004) and gait analysis (right: temporal step time: p < 0.0001, temporal cycle time: p < 0.001, temporal double support time: p < 0.0001; left: temporal step time: p < 0.0001, temporal cycle time: p < 0.0001, temporal double support time: p < 0.0001). TDS in elderly male stroke patients suggests that the characteristics of gait performance in these patients may be improved by increasing static balance, dynamic balance and gait velocity. It is hoped that the results of this trial will provide new information on the effects of TDS on balance stability and gait ability in stroke patients, through changes in stability of the lower extremities. Level III, Case-control Study.

Cognitive Loading Produces Similar Change in Postural Stability in Patients With Chronic Ankle Instability and Controls

Purpose

While postural stability is compromised in individuals with chronic ankle instability (CAI), few studies have attempted to examine how performing simultaneous cognitive and balancing tasks may alter the complexity of the center of pressure. The purpose of this study was to compare postural stability in patients with CAI to controls during a dual-task condition via sample entropy.

Methods

Thirty participants (15 CAI, 15 healthy control) performed 3-trials of single-leg stance for 60-seconds each under two different conditions: single-task and dual-task (serial subtraction). Sample entropy (SampEn), a measure of pattern regularity, was calculated from the center of pressure excursion in the anterio-posterior (AP) and medio-lateral (ML) directions. 2x2 mixed-model ANOVAs determined any differences by task or group (p≤0.05).

Results

SampEn-AP decreased in the dual-task condition compared to single-task, single-leg balance across groups (F1,28=8.23, p=0.008, d=0.53). A significant interaction for group by task was found for SampEn-ML (F1,28=4.18, p=0.05), but post hoc testing failed to reveal significant differences. Serial subtraction was completed with significantly fewer errors during dual-task compared to single-task (F1,27=12.75, p=0.001, d=0.66).

Conclusions

Patients with CAI do not display differences in regularity of postural stability, even when attention is divided. However, the addition of serial subtraction increased the regularity of AP center-of-pressure motion. Increased regularity may suggest a change in motor control strategy, reducing natural fluctuations and flexibility within movement patterns during more challenging tasks. Clinicians could utilize dual-task situations during rehabilitation of patients with CAI, in order to adequately restore stability and function when attention is divided.

Effects of Fresnel prism glasses on balance and gait in stroke patients with hemiplegia: A randomized controlled trial pilot study

BACKGROUND

Fresnel prism shifts the field of view and converts object position in space, but its effect on stroke patients without unilateral neglect has not been examined.

OBJECTIVE

We aimed to investigate the effect of Fresnel prism glasses on balance and gait in stroke patients with hemiplegia.

METHODS

This study included 17 stroke patients with hemiplegia without unilateral neglect. Balance and gait training were applied in the control group (n= 9), and Fresnel prism glasses were applied with balance and gait training in the experimental group (n= 8). In all groups, interventions were done for 30 min/day for 5 times/week for 4 weeks. Motor-free visual perception test for visual perception (MVPT), Berg Balance Scale (BBS), and functional reach test (FRT) for dynamic balance ability, and gait were performed. Measurements were done before and after interventions.

RESULTS

MVPT showed no significant difference between the groups (p> 0.05). A significant increase in BBS and FRT results was found before and after interventions in the experimental group (p< 0.05). Gait variables showed significant difference in the experimental group (p< 0.05).

CONCLUSION

Fresnel prism glasses may effectively improve dynamic balance and gait functions by shifting body weight to the affected side of stroke patients with hemiplegia without vision loss.

Positive Balance Recovery in Ischemic Post-Stroke Patients with Delayed Access to Physical Therapy

BACKGROUND

Since patient's prognosis after stroke depends on its severity, brain location, and type early intervention is strongly recommended.

OBJECTIVE

We aimed to determine whether it is still possible to improve balance in chronic patients, who suffered Intracerebral Hemorrhagic Strokes (ICHS) or Ischemic Strokes (IS), after later intervention.

METHODS

34 patients who had unilateral ICHS or IS and involved the motor cortex or sub-cortical areas took part in the study. The patients underwent clinical balance evaluation (using the Berg Balance Scale) and posturographic assessment (with a capacitive pressure platform) at the time of admission to the physiotherapy and at the end of the study. The physiotherapy intervention consisted of 20 sessions of 60 minutes carried out 3 times per week, following standard protocols: stretching; passive range of motion (ROM); active assistive ROM; active ROM; resistance training; coordination and balance activities while sitting and standing, and Large-muscle activities such as walking, treadmill, stationary cycle, combined arm-leg ergometry, arm ergometry, seated stepper and circuit training.

RESULTS

In the posturographic assessment, the IS group had significant lower amplitude of center of pressure (COP) anteroposterior displacement, after physical therapy intervention. Also, the 95% confidence ellipse area of the COP and the total COP displacement showed significant interaction between the subtype of stroke and the assessment period, meaning the IS group improved their balance after treatment on the contrary of ICHS. The structural analysis of the COP reinforced these results. On the other hand, no difference was observed in the clinical scale, between the assessment periods, for any subtype of stroke.

CONCLUSION

Only IS patients have shown balance improvements after conventional intervention. COP measurements are more sensible to assess balance in chronic patients than Berg Balance Scale.