Impact of Spasticity on Balance Control during Quiet Standing in Persons after Stroke

Effects of dry needling on spasticity and motor function in paralympic athletes: a study protocol for a randomised controlled trial

No study has evaluated the effects of dry needling on Paralympic athletes. Therefore, in this study, we will evaluate the effect of dry needling on lower limb spasticity and motor performance, as well as the range of motion of Paralympic athletes. The study will be a triple-blinded, randomised controlled trial. Twenty-four athletes aged 18-45 in T35-T38 groups of the International Paralympic Committee classification will be included in the study. Twelve participants will receive dry needling of the quadriceps and gastrocnemius muscles, and 12 will receive placebo treatment with sham needles at similar points. We will assess the spasticity of the quadriceps and gastrocnemius muscles using the Modified Ashworth Scale, evaluate motor function using the Selective Control Assessment of the Lower Extremity Scale and measure ankle range of motion (ROM) with a goniometer. Considering our hypothesis, the athletes who will undergo the dry needling are supposed to achieve better improvements in spasticity, ROM and motor performance. This study can provide useful information to help better decide on managing complications in Paralympics and its long-term outcomes, to cover the current lack in the literature.

Reliability of force plate-based measures of standing balance in the sub-acute stage of post-stroke recovery

Background

Difficulty controlling balance is one of the major contributors to the increased risk of falls among individuals with stroke. It is important to use reliable and objective measures to improve examination of balance impairments post-stroke, and to in turn inform clinical decision-making. The main objective of this study was to examine the relative and absolute reliabilities of force plate-based balance measures in quiet standing, in the sub-acute stage of stroke recovery.

Methods

Twenty-four people with sub-acute stroke (mean age = 61 years) performed two trials of quiet standing, each 30 s long. Sixteen force plate-based balance measures in the time, frequency, or nonlinear domains were calculated. Within-session test-retest reliabilities were investigated using intraclass correlation coefficient (ICC), standard error of measurement, and minimal detectable change.

Results

Mean speed of displacements of the centre of pressure along the anterior-posterior axis (ICC = 0.91; CI95 % = [0.83, 0.95]), and directional weight-bearing asymmetry (ICC = 0.91; CI95 % = [0.82, 0.95]) demonstrated high relative reliabilities, followed by the speed-based symmetry index and absolute weight-bearing asymmetry (both ICCs = 0.86; CI95 % = [0.74, 0.93]).

Conclusions

Mean speeds of centre of pressure, directional weight-bearing asymmetry, and speed-based symmetry index are the most reliable force plate-based measures that were evaluated in our study, and can be included in the balance assessments of individuals within the sub-acute stage of post-stroke recovery. These findings can better inform clinicians about the specific balance problems experienced by people in this population.

Correlation analysis of balance function with plantar pressure distribution and gait parameters in patients with cerebral infarction in the basal ganglia region

Objective

To analyze the correlation between balance function and gait parameters of patients with basal ganglia infarction. And to observe the influence of balance function on plantar pressure and hemiplegia gait based on the Berg Balance Scale (BBS) score.

Methods

One hundred and forty patients with cerebral infarction hemiplegia in the basal ganglia region (a study group, n = 140) and healthy people (a control group, n = 140) were enrolled. The study group was evaluated with the BBS, the 10 m walking test (10MWT), and the timed up-and-go test (TUGT). The gait parameters and the peak plantar pressure were measured in both groups while walking, and the differences between the groups were compared. In addition, the characteristics of the plantar pressure curve of the hemiplegic and non-hemiplegic sides during walking and the correlation between the 10MWT, the TUGT, the plantar pressure peak, the gait parameters,and the BBS score were analyzed in the study group.

Results

The peak plantar pressure of the forefoot and heel, stride length, lateral symmetry, stand phase, swing phase, and dual stand phase of both sides in the study group were significantly lower than those in the control group (P < 0.05). The BBS score negatively correlated with the 10MWT, the TUGT, the peak plantar pressure of the hemiplegic forefoot, midfoot, and the non-hemiplegic midfoot, the anterior to posterior position (ant/post position), hemiplegic stand phase, and the dual stand phase (P < 0.05). The BBS score positively correlated with the hemiplegic swing phase and stride length (P < 0.05).

Conclusion

A correlation was found between the forefoot plantar pressure and the stand phase of the hemiplegic limbs, the ant/post position, and the balance function after basal ganglion cerebral infarction. This association can be used in walking and balance assessment for stroke rehabilitation. Correcting forefoot pressure or the front and ant/post position can improve balance function.

Automatic characterization of stroke patients' posturography based on probability density analysis

OBJECTIVE

The probability density analysis was applied to automatically characterize the center of pressure (COP) data for evaluation of the stroke patients' balance ability.

METHODS

The real-time COP coordinates of 38 stroke patients with eyes open and closed during quiet standing were obtained, respectively, from a precision force platform. The COP data were analyzed and characterized by the commonly used parameters: total sway length (SL), sway radius (SR), envelope sway area (EA), and the probability density analysis based parameters: projection area (PA), skewness (SK) and kurtosis (KT), and their statistical correlations were analyzed. The differences of both conventional parameters and probability density parameters under the conditions of eyes open (EO) and eyes closed (EC) were compared.

RESULTS

The PA from probability density analysis is strongly correlated with SL and SR. Both the traditional parameters and probability density parameters in the EC state are significantly different from those in the EO state. The obtained various statokinesigrams were calculated and categorized into typical sway types through probability density function for clinical evaluation of the balance ability of stroke patients.

CONCLUSIONS

The probability density analysis of COP data can be used to characterize the posturography for evaluation of the balance ability of stroke patients.

Effects of ankle-foot orthoses on the stability of post-stroke hemiparetic gait

BACKGROUND

Ankle-foot orthoses are used to improve gait stability in patients with post-stroke gait; however, there is not enough evidence to support their beneficial impact on gait stability.

AIM

To investigate the effects of ankle-foot orthoses on post-stroke gait stability.

DESIGN

An experimental study with repeated measurements of gait parameters with and without orthosis.

SETTING

Inpatients and outpatients in the Fujita Health University Hospital, Toyoake, Japan.

POPULATION

Thirty-two patients (22 males; mean age 48.3±20.0 years) with post-stroke hemiparesis participated in the study.

METHODS

Three-dimensional treadmill gait analysis was performed with and without ankle-foot orthosis for each participant. Spatiotemporal parameters, their coefficient of variation, and margin of stability were evaluated. Toe clearance, another major target of orthosis, was also examined. The effect of orthosis in the patients with severe (not able to move within the full range of motion, defying gravity) and mild ankle impairment (able to move within the full range but have problem with speed and/or smoothness of the ankle movement) was compared.

RESULTS

In the total group comparison, the decrease in the coefficient of variation of step width (P=0.012), and margin of stability on the paretic side (P=0.023) were observed. In the severe ankle impairment groups, the decreased in the coefficient of variation of the non-paretic step length (P=0.007), stride length (P=0.037), and step width (P=0.033) and margin of stability on the paretic side (P=0.006) were observed. No significant effects were observed in the mild ankle impairment group; rather, the coefficient of variation of non-paretic step length increased with the use of orthosis in this group (P=0.043); however, toe clearance increased with the use of ankle-foot orthosis (P=0.041).

CONCLUSIONS

Ankle-foot orthoses improved gait stability indices; however, the effect was either not significant or showed possible worsening in the patients with mild ankle impairment, while the effect on toe clearance was significant. These results suggest that the effects of using orthoses in patients with mild impairment should be carefully evaluated.

CLINICAL REHABILITATION IMPACT

Understanding the effects of ankle-foot orthoses on the stability of post-stroke gait and their relationship with ankle impairment severity may support clinical decision-making while prescribing orthosis for post-stroke hemiparesis.

Recent State of Wearable IMU Sensors Use in People Living with Spasticity: A Systematic Review

Spasticity is a disabling characteristic of neurological disorders, described by a velocity-dependent increase in muscle tone during passive stretch. During the last few years, many studies have been carried out to assess spasticity using wearable IMU (inertial measurements unit) sensors. This review aims to provide an updated framework of the current research on IMUs wearable sensors in people living with spasticity in recent studies published between 2017 and 2021. A total of 322 articles were screened, then finally 10 articles were selected. Results show the lack of homogenization of study procedures and missing apparatus information in some studies. Still, most studies performed adequately on measures of reporting and found that IMUs wearable data was successful in their respective purposes and goals. As IMUs estimate translational and rotational body motions, we believe there is a strong potential for these applications to estimate velocity-dependent exaggeration of stretch reflexes and spasticity-related characteristics in spasticity. This review also proposes new directions of research that should be challenged by larger study groups and could be of interest to both researchers as well as clinicians. The use of IMUs to evaluate spasticity is a promising avenue to provide an objective measurement as compared to non-instrumented traditional assessments.

Pendulum test in chronic hemiplegic stroke population: additional ambulatory information beyond spasticity

Spasticity measured by manual tests, such as modified Ashworth scale (MAS), may not sufficiently reflect mobility function in stroke survivors. This study aims to identify additional ambulatory information provided by the pendulum test. Clinical assessments including Brünnstrom recovery stage, manual muscle test, MAS, Tinetti test (TT), Timed up and go test, 10-m walk test (10-MWT), and Barthel index were applied to 40 ambulant chronic stroke patients. The pendular parameters, first swing excursion (FSE) and relaxation index (RI), were extracted by an electrogoniometer. The correlations among these variables were analyzed by the Spearman and Pearson partial correlation tests. After controlling the factor of motor recovery (Brünnstrom recovery stage), the MAS of paretic knee extensor was negatively correlated with the gait score of TT (r =  − 0.355, p = 0.027), while the FSE revealed positive correlations to the balance score of TT (r = 0.378, p = 0.018). RI were associated with the comfortable speed of 10-MWT (r = 0.367, p = 0.022). These results suggest a decrease of knee extensor spasticity links to a better gait and balance in chronic stroke patients. The pendular parameters can provide additional ambulatory information, as complementary to the MAS. The pendulum test can be a potential tool for patient selection and outcome assessment after spasticity treatments in chronic stroke population.

Efficacy and Optimal Dose of Botulinum Toxin A in Post-Stroke Lower Extremity Spasticity: A Systematic Review and Meta-Analysis

Post-stroke spasticity impedes patients’ rehabilitation progress. Contradictory evidence has been reported in using Botulinum Neurotoxin type A (BoNT-A) to manage post-stroke lower extremity spasticity (PLES); furthermore, an optimum dose of BoNT-A for PLES has not yet been established. Therefore, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to identify the efficacy and optimal dose of BoNT-A on PLES. "Meta" and "Metafor" packages in R were used to analyze the data. Hedges’ g statistic and random effect model were used to calculate and pool effect sizes. Twelve RCTs met the eligibility criteria. Muscle tone significantly improved in week four, week eight, and maintained to week twelve after BoNT-A injection. Improvements in functional outcomes were found, some inconsistencies among included studies were noticed. Dosage analysis from eight studies using Botox® and three studies using Dysport® indicated that the optimum dose for the commonest pattern of PLES (spastic plantar flexors) is medium-dose (approximately 300U Botox® or 1000 U Dysport®). BoNT-A should be regarded as part of a rehabilitation program for PLES. Furthermore, an optimal rehabilitation program combined with BoNT-A management needs to be established. Further studies should also focus on functional improvement by BoNT-A management in the early stage of stroke.

Role of Spasticity Severity in the Balance of Post-stroke Patients

Background: Lower limb spasticity after stroke is common that can affect the balance, increase the risk of falling, and reduces the quality of life. Objective: First, evaluate the effects of spasticity severity of ankle plantar flexors on balance of patients after stroke. Second, to determine the relationship between the spasticity severity with ankle proprioception, passive ankle dorsiflexion range of motion (ROM), and balance confidence. Methods: Twenty-eight patients with stroke based on the Modified Modified Ashworth Scale (MMAS) were divided into two groups: High Spasticity Group (HSG) (MMAS > 2) (n = 14) or a Low Spasticity Group (LSG) (MMAS ≤ 2) (n = 14). The MMAS scores, Activities-Specific Balance Confidence Questionnaire, postural sway of both affected and non-affected limbs under the eyes open and eyes closed conditions, timed up and go (TUG) test, passive ankle dorsiflexion ROM, and ankle joint proprioception were measured. Results: The ankle joint proprioception was significantly better in the LSG compared to the HSG (p = 0.01). No significant differences were found between the LSG and HSG on all other outcome measures. There were no significant relationships between the spasticity severity and passive ankle dorsiflexion ROM, and balance confidence. Conclusion: The severity of ankle plantar flexor spasticity had no effects on balance of patients with stroke. However, the ankle joint proprioception was better in patients with low spasticity. Our findings suggest that the balance is affected regardless of the severity of the ankle plantar flexor spasticity in this group of participants with stroke.

Short-Step Adjustment and Proximal Compensatory Strategies Adopted by Stroke Survivors With Knee Extensor Spasticity for Obstacle Crossing

Stroke survivors adopt cautious or compensatory strategies for safe and successful obstacle crossing. Although knee extensor spasticity is a common independent secondary sensorimotor disorder post-stroke, few studies have examined the step adjustment and compensatory strategies used by stroke survivors with knee extensor spasticity during obstacle crossing. This study aimed to compare the differences in the kinematics and kinetics during obstacle crossing between stroke survivors with and without knee extensor spasticity, and to identify knee extensor spasticity-related differences in step adjustment and compensatory strategies. Twenty stroke subjects were divided into a spasticity group [n = 11, modified Ashworth scale (MAS) ≥ 1] and a non-spasticity group (n = 9, MAS = 0), based on the MAS score of the knee extensor. Subjects were instructed to walk at a self-selected speed on a 10-m walkway and step over a 15 cm obstacle. A ten-camera 3D motion analysis system and two force plates were used to collect the kinematic and kinetic data. During the pre-obstacle phase, stroke survivors with knee extensor spasticity adopted a short-step strategy to approach the obstacle, while the subjects without spasticity used long-step strategy. During the affected limb swing phase, the spasticity group exhibited increased values that were significantly higher than those seen in the non-spasticity group for the following measurements: pelvic lateral tilt angle, trunk lateral tilt angle, medio-lateral distance between the ankle and ipsilateral hip joint, hip work contributions, the inclination angles between center of mass and center of pressure in anterior–posterior and medio-lateral directions. These results indicate that the combined movement of the pelvic, trunk lateral tilt, and hip abduction is an important compensatory strategy for successful obstacle crossing, but it sacrifices some balance in the sideways direction. During the post-obstacle phase, short-step and increase step width strategy were adopted to reestablish the walking pattern and balance control. These results reveal the step adjustment and compensatory strategies for obstacle crossing and also provide insight into the design of rehabilitation interventions for fall prevention in stroke survivors with knee extensor spasticity.

Effect of Ankle Plantar Flexor Spasticity Level on Balance in Patients With Stroke: Protocol for a Cross-Sectional Study

BACKGROUND

The lower limb spasticity after stroke can affect the balance and gait of patients with stroke.

OBJECTIVE

The aim of this study is to assess the effects of ankle plantar flexor spasticity level on balance in patients with stroke.

METHODS

Patients with stroke were recruited from neurology and physiotherapy clinics in Tehran, Iran. Based on the level of ankle plantar flexor spasticity according to the Modified Modified Ashworth Scale (MMAS), the eligible patients with stroke were divided into 2 groups: high spasticity (MMAS score≥2) and low spasticity (MMAS score<2). The primary outcome measures were the MMAS scores, Activities-Specific Balance Confidence questionnaire scores, eyes-open and eyes-closed posturography measures, and Timed Up and Go test results. The secondary outcome measures were the ankle passive range of motion and ankle joint proprioception. The t test, mixed model univariate analysis of variance, and Spearman rank correlation were used for statistical analysis.

RESULTS

Data collection and statistical analysis are complete. The interpretation of results is underway. We expect the results to be published in winter 2020.

CONCLUSIONS

We believe that patients with high ankle plantar flexor spasticity after stroke will demonstrate greater balance dysfunction, which will worsen with impaired proprioception, passive range of motion, and eyes closed.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/16045.

Fifteen Years of Wireless Sensors for Balance Assessment in Neurological Disorders

Balance impairment is a major mechanism behind falling along with environmental hazards. Under physiological conditions, ageing leads to a progressive decline in balance control per se. Moreover, various neurological disorders further increase the risk of falls by deteriorating specific nervous system functions contributing to balance. Over the last 15 years, significant advancements in technology have provided wearable solutions for balance evaluation and the management of postural instability in patients with neurological disorders. This narrative review aims to address the topic of balance and wireless sensors in several neurological disorders, including Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, stroke, and other neurodegenerative and acute clinical syndromes. The review discusses the physiological and pathophysiological bases of balance in neurological disorders as well as the traditional and innovative instruments currently available for balance assessment. The technical and clinical perspectives of wearable technologies, as well as current challenges in the field of teleneurology, are also examined.