What Is Wrong with Balance in Parkinson's Disease?

The vestibulo-ocular and vestibulospinal reflexes minimally impact the freezing of gait in patients with early-to-moderate Parkinson's disease

Introduction

Freezing of gait (FOG) is a disabling condition that often leads to falls and severe postural instability in patients with Parkinson's disease (PD). This study aimed to determine whether FOG is associated with the integrity of the vestibulo-ocular (VOR) and vestibulospinal reflexes (VSR).

Methods

We retrospectively collected 138 patients with de novo PD at a tertiary medical center between February 2022 and February 2025. Each patient was queried and assessed for FOG status during the initial assessment. All patients underwent video head-impulse tests (video-HIT), cervical vestibular-evoked myogenic potential (cVEMP), ocular vestibular-evoked myogenic potential (oVEMP), and motion analysis.

Results

FOG was observed in 23 patients (23/138, 17 %). The head impulse gain of the VOR did not differ between freezers and non-freezers in any semicircular canal. The new FOG questionnaire score showed no correlation with the VOR gain for any canal. The oVEMP and cVEMP parameters did not differ between freezers and non-freezers either. Multivariable logistic regression analysis revealed a positive association between FOG and MDS-UPDRS-III (p = 0.016). However, FOG was not associated with the VOR gain in any canal or abnormalities on oVEMP or cVEMP.

Conclusions

Our preliminary data suggest that FOG is associated with the severity of motor symptoms in patients with early-to-moderate PD. While the integrity of the VOR or VSR is not currently associated with FOG, a well-designed future study could provide more nuanced insights into the relationship with these factors.

Exploring Non-invasive Brain Stimulation Effects on Physical Outcomes in People With Parkinson's Disease: An Umbrella Evidence Mapping Review With Meta-analyses

Background. Non-invasive brain stimulation (NIBS) is sometimes used alongside medication to alleviate motor symptoms in people with Parkinson's disease (PD). However, the evidence supporting NIBS's effectiveness for improving motor function in PD patients is uncertain. Objective. This umbrella review aims to synthesize recent systematic reviews and meta-analyses that have evaluated the effectiveness of NIBS in improving motor function in people with PD, with a key focus being to examine the quality of the evidence presented. Methods. The review protocol was registered in PROSPERO (CRD42022380544) and conducted per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search strategy was guided by the Population, Intervention, Comparison, and Outcome framework, focusing on individuals with idiopathic PD (Hoehn and Yahr stages 1-4). The review included studies comparing various NIBS techniques (eg, repetitive transcranial magnetic stimulation and transcranial direct current stimulation) to sham or alternative treatments, targeting motor and cognitive regions. Six databases were searched up to June 2024. Methodological quality was assessed using Assessment of Multiple Systematic Reviews 2 (AMSTAR2), and random-effects meta-analyses were performed to pool standardized mean differences (SMDs). Results. The final analysis included 31 meta-analyses and 10 systematic reviews. Overall, the reviews were rated as moderate quality (54% average for AMSTAR2). NIBS showed a small-to-moderate effect on motor function (Unified Parkinson's Disease Rating Scale-Section III scores; SMD = -0.80), functional mobility (gait speed and timed-up-and-go; SMD = -0.39), and freezing of gait (SMD = -0.58), but no significant effect on balance. Conclusion. NIBS offers small-to-moderate benefits for motor symptoms and functional movement in PD, though it does not significantly impact balance. Practitioners should consider the variety of techniques and treatment parameters before application.

Evaluating the Effects of Levodopa on the Vestibulo-Ocular Reflex in Parkinson's Disease: A Case Series

PURPOSE

Parkinson's disease (PD) is a neurodegenerative disorder primarily affecting individuals over 60 years old. The disorder is characterized by motor symptoms due in large part to the loss of dopamine-producing neurons. The vestibular system, crucial for maintaining balance, may be impacted in PD, contributing to balance issues through dysfunction in the vestibulo-ocular reflex. In this study, we aim to describe differences in vestibular responses before and after use of levodopa (L-DOPA) in patients with PD.

METHOD

The study evaluated nine PD patients who underwent videonystagmography, video head impulse testing, and rotational chair testing both on and off their dopaminergic medications. Effect sizes of the mean difference was measured using Cohen's d.

RESULTS

The results revealed a general trend of increase in vestibular responses from the off stage to the on stage across all the vestibular testing mechanisms. The p values were all > .05, and the Cohen's d 95% confidence interval (CI) ranged from small to moderate effects with wide CIs consistent with the small sample.

CONCLUSIONS

In this case series of nine patients with PD, we identified a general trend of a small increase in vestibular responses in the on state of L-DOPA compared with the off state of L-DOPA. The significance and clinical implications of such differences should be evaluated in larger samples.

Sensory reweighting for balance in people living with Parkinson's Disease: Postural adaptation, muscle co-contraction, and perceptual delays

BACKGROUND

Postural instability is common in people with Parkinson's Disease (PwPD), increasing their risk of injurious falls. Evidence suggests a sensory reweighting deficit in PwPD, along with compensatory muscle co-contraction in response to postural challenges. During balance tasks requiring sensory reweighting, older adults exhibit elevated postural sway and muscle co-contraction, as well as longer perceptual delays, compared to young adults. Such responses may be exacerbated in PwPD, with implications for fall risk.

RESEARCH QUESTION

The aim of this study was to assess postural sway, muscle co-contraction, and perceptual delays in PwPD and healthy age-matched controls during a sensory reweighting balance task.

METHODS

Eleven PwPD and 16 control participants completed a sensory reweighting protocol: standing without vision on a fixed platform (2-min), which then undergoes a period of body sway-referencing (3-min) before returning to its fixed position (2.5-min). Anteroposterior (AP) path length, co-contraction index (CCI), and perceptual delay were analysed across task phases.

RESULTS

PwPD showed a longer delay in perceiving when the body sway-referenced platform returned to a fixed position. This perceptual delay in PwPD (43.40-s) was over double that observed in control participants (21.25-s). AP path length and co-contraction aftereffects were longer in control participants than PwPD.

SIGNIFICANCE

Where conditions require it, PwPD can effectively adjust their reliance on proprioceptive information for postural control. However, the significant delay shown by PwPD in perceiving changes to sensory conditions could be detrimental during everyday sensory transitions, potentially increasing fall risk.

A methodological scoping review on EMG processing and synergy-based results in muscle synergy studies in Parkinson's disease

Introduction

Parkinson's Disease is the second most common neurodegenerative disease in the world. It affects mainly people over 65 and the incidence increases with age. It is characterized by motor and non-motor symptoms and several clinical manifestations. The most evident symptom that affects all patients with Parkinson's Disease is the impairment of motor control, including bradykinesia, tremor, joint rigidity, and postural instability. In the literature, it has been evaluated with muscle synergies, a well-known method for evaluating motor control at the muscular level. However, few studies are available and there is still a major gap to fill to exploit the potential of the method for assessing motor control in Parkinson's Disease, both in the understanding of physiopathology and clinical practice.

Methods

In the light of understanding and fostering future developments for the field, in this review we initially screened 212 papers on Scopus and Web of Science and selected 15 of them to summarize the main features of investigations that employed muscle synergies to analyze patients with Parkinson's Disease. We detailed the features of the screened papers by reporting the clinical findings, a detailed report of EMG processing choices and synergy-based results.

Results

We found that synergistic control is in general altered in patients with Parkinson's Disease, but it can improve if patients are subjected to pharmacological and rehabilitation therapies. Moreover, a further understanding of synergistic control in Parkinson's patients is needed.

Discussion

We discuss the future developments in the field with a detailed assessment of the topic on the view of physicians, including the most promising lines of research for clinical practice and from the perspective of engineers, for methodological application of synergistic approaches.

Still Functional but Limited Postural Adaptation for Individuals With Parkinson's Disease in Goal-Directed Visual Tasks

Patients with Parkinson's disease (PD) notably exhibit impairments in posture and visual attention. The objective of the present study was to determine whether PD patients were able to exhibit adaptive postural control in a goal-directed visual task. We hypothesized that the patients would reduce their centre of pressure (COP) movement and/or postural sway to a lesser extent than age-matched controls in the goal-directed visual (search) task, compared with the control free-viewing task (i.e., a lower degree of relative postural adaptation). We also expected the PD patients to sway more than controls in the goal-directed task (i.e., a lower degree of absolute adaptive postural control). The study included 39 PD patients (mean age: 59; mean Hoehn and Yahr stage: 2.1; mean Movement Disorder Society-Unified Parkinson's Disease Rating Scale score: 22; mean Montreal Cognitive Assessment score: 28 (on-drug)) and 40 age-matched adults (mean age: 62 years). The participants gazed at domestic ecological images (visual angle: 100°). Movements of the COP, head, upper back and lower back and variations in pupil dilatation were analysed. As expected, PD patients exhibited greater COP and body sway than controls in both tasks (p < 0.05). Unexpectedly, the difference in COP and/or body sway between the two tasks was greater in PD patients than in controls (p < 0.05). Our results showed that PD patients are able to exhibit adaptive postural control for goal-directed visual tasks. On a practical level and at a more general level, our findings emphasize the likely benefits of rehabilitation with goal-directed tasks requiring a visual attentional focus (walking on footprints on the ground, etc.).

Motor actions across psychiatric disorders: A research domain criteria (RDoC) perspective

The motor system is critical for understanding the pathophysiology and treatment of mental illness. Abnormalities in the processes that allow us to plan and execute movement in a goal-directed, context-appropriate manner (i.e., motor actions) are especially central to clinical motor research. Within this context, the NIMH Research Domain Criteria (RDoC) framework now includes a Motor Actions construct within the recently incorporated Sensorimotor Systems Domain, providing a useful framework for conducting research on motor action processes. However, there is limited available resources for understanding or implementing this framework. We address this gap by providing a comprehensive critical review and conceptual integration of the current clinical literature on the subconstructs comprising the Motor Actions construct. This includes a detailed discussion of each Motor Action subconstruct (e.g., action planning/execution) and its measurement across different units of analysis (e.g., molecules to behavior), the temporal and conceptual relationships among the Motor Action subconstructs (and other relevant RDoC domain constructs), and how abnormalities in these Motor Action subconstructs manifest in mental illness. Together, the review illustrates how motor system dysfunction is implicated in the pathophysiology of many psychiatric conditions and demonstrates shared and distinct mechanisms that may account for similar manifestations of motor abnormalities across disorders.

Exercise, Neuroprotective Exerkines, and Parkinson's Disease: A Narrative Review

Parkinson's disease (PD) is a prevalent neurodegenerative disease in which treatment often includes an exercise regimen. Exercise is neuroprotective in animal models of PD, and, more recently, human clinical studies have verified exercise's disease-modifying effect. Aerobic exercise and resistance training improve many of PD's motor and non-motor symptoms, while neuromotor therapy and stretching/flexibility exercises positively contribute to the quality of life in people with PD. Therefore, understanding the role of exercise in managing this complex disorder is crucial. Exerkines are bioactive substances that are synthesized and released during exercise and have been implicated in several positive health outcomes, including neuroprotection. Exerkines protect neuronal cells in vitro and rodent PD models in vivo. Aerobic exercise and resistance training both increase exerkine levels in the blood, suggesting a role for exerkines in the neuroprotective theory. Many exerkines demonstrate the potential for protecting the brain against pathological missteps caused by PD. Every person (people) with Parkinson's (PwP) needs a comprehensive exercise plan tailored to their unique needs and abilities. Here, we provide an exercise template to help PwP understand the importance of exercise for treating PD, describe barriers confronting many PwP in their attempt to exercise, provide suggestions for overcoming these barriers, and explore the role of exerkines in managing PD. In conclusion, exercise and exerkines together create a powerful neuroprotective system that should contribute to slowing the chronic progression of PD.

EFFECTS OF TREADMILL GAIT TRAINING ON BALANCE IN PARKINSON'S PATIENTS AFTER DEEP BRAIN STIMULATION

Objective

After deep brain stimulation (DBS), patients with Parkinson's disease (PD) typically still present significant gait and postural stability problems, and thus additional interventions are needed. In this way, our purpose was evaluate the comparative effectiveness of treadmill training, with and without body weight support, on balance outcomes among patients with PD after DBS.

Methods

Eleven patients with PD that were using bilateral subthalamic nucleus DBS were evaluated using Time Up and Go test (TUG); Berg Balance Scale (BBS) and Static Posturography. In phase 1, all subjects participated in 8-weeks of treadmill training in conjunction with conventional physiotherapy. After six weeks (wash-out), each patient then participated in a subsequent 8-weeks of treadmill training with partial body weight support.

Results

After the phase 1, there were improvements on the cognitive TUG performance (Before: 15.7 ± 1,8 sec; After: 13.7 ± 3.1 sec; p < 0.01) and an increase of anteroposterior and medio-lateral body oscillation with eyes closed. After the phase 2, there were improvements in conventional (Before: 12.3 ± 2.0 sec; After: 10.7 ± 1.7 sec; p < 0.01) and cognitive (Before: 14.6 ± 3.5 sec; After: 12.5 ± 1.6 sec; p < 0.05) TUG performances. There were no significant changes in the Berg Balance Scale following either training protocol.

Conclusion

Both trainings improved static and dynamic balance and had similar results; however, supported treadmill training seemed to be a potentially superior option, as patients tended to feel safer. Level of Evidence II, therapeutic studies - investigation of treatment outcomes.

Dual-Task vs. Single-Task Gait Training to Improve Spatiotemporal Gait Parameters in People with Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

People with Parkinson's disease (pwPD) present alterations of spatiotemporal gait parameters that impact walking ability. While preliminary studies suggested that dual-task gait training improves spatiotemporal gait parameters, it remains unclear whether dual-task gait training specifically improves dual-task gait performance compared to single-task gait training. The aim of this review is to assess the effect of dual-task training relative to single-task gait training on specific gait parameters during dual-task tests in pwPD.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), searching three electronic databases. Two reviewers independently selected RCTs, extracted data, and applied the Cochrane risk-of-bias tool for randomized trials (Version 2) and the GRADE framework for assessing the certainty of evidence. The primary outcomes were dual-task gait speed, stride length, and cadence. Secondary outcomes included dual-task costs on gait speed, balance confidence, and quality of life.

RESULTS

We included 14 RCTs (548 patients). Meta-analyses showed effects favoring dual-task training over single-task training in improving dual-task gait speed (standardized mean difference [SMD] = 0.48, 95% confidence interval [CI] = 0.20-0.77; 11 studies; low certainty evidence), stride length (mean difference [MD] = 0.09 m, 95% CI = 0.04-0.14; 4 studies; very low certainty evidence), and cadence (MD = 5.45 steps/min, 95% CI = 3.59-7.31; 5 studies; very low certainty evidence). We also found a significant effect of dual-task training over single-task training on dual-task cost and quality of life, but not on balance confidence.

CONCLUSIONS

Our findings support the use of dual-task training relative to single-task training to improve dual-task spatiotemporal gait parameters in pwPD. Further studies are encouraged to better define the features of dual-task training and the clinical characteristics of pwPD to identify better responders.

Spatial variability and directional shifts in postural control in Parkinson's disease

Individuals with Parkinson's disease exhibit tremors, rigidity, and bradykinesia, disrupting normal movement variability and resulting in postural instability. This comprehensive study aimed to investigate the link between the temporal structure of postural sway variability and Parkinsonism by analyzing multiple datasets from young and older adults, including individuals with Parkinson's disease, across various task conditions. We used the Oriented Fractal Scaling Component Analysis (OFSCA), which identifies minimal and maximal long-range correlations within the center of pressure time series, allowing for detecting directional changes in postural sway variability. The objective was to uncover the primary directions along which individuals exerted control during the posture. The results, as anticipated, revealed that healthy adults predominantly exerted control along two orthogonal directions, closely aligned with the anteroposterior (AP) and mediolateral (ML) axes. In stark contrast, older adults and individuals with Parkinson's disease exhibited control along suborthogonal directions that notably diverged from the AP and ML axes. While older adults and those with Parkinson's disease demonstrated a similar reduction in the angle between these two control directions compared to healthy older adults, their reliance on this suborthogonal angle concerning endogenous fractal correlations exhibited significant differences from the healthy aging cohort. Importantly, individuals with Parkinson's disease did not manifest the sensitivity to destabilizing task settings observed in their healthy counterparts, affirming the distinction between Parkinson's disease and healthy aging.

Imbalance and gait impairment in Parkinson's disease: discussing postural instability and ataxia

Gait and balance difficulties pose significant clinical challenges in Parkinson's disease (PD). The impairment of physiological mechanisms responsible for maintaining natural orthostatism plays a central role in the pathophysiology of postural instability observed in PD. In addition to the well-known rigidity and abnormalities in muscles and joints, various brain regions involved in the regulation of posture, balance, and gait, such as the basal ganglia, cerebellum, and brainstem regions like the pontine peduncle nucleus, are affected in individuals with PD. The recognition of the cerebellum's role in PD has been increasingly acknowledged. Cortical areas and their connections are associated with freezing of gait, a type of frontal lobe ataxia commonly observed in PD. Furthermore, impairments in the peripheral nervous system, including those caused by levodopatherapy, can contribute to gait impairment and imbalance in PD patients. Consequently, individuals with PD may exhibit frontal ataxia, sensory ataxia, and even cerebellar ataxia as underlying causes of gait disturbances and imbalance, starting from the early stages of the disease. The complex interplay between dysfunctional brain regions, impaired cortical connections, and peripheral nervous system abnormalities contributes to the multifaceted nature of gait and balance difficulties in PD. Understanding the intricate mechanisms is crucial for the development of effective therapeutic approaches targeting these specific deficits in PD.

Older adults and individuals with Parkinson's disease control posture along suborthogonal directions that deviate from the traditional anteroposterior and mediolateral directions

A rich and complex temporal structure of variability in postural sway characterizes healthy and adaptable postural control. However, neurodegenerative disorders such as Parkinson's disease, which often manifest as tremors, rigidity, and bradykinesia, disrupt this healthy variability. This study examined postural sway in young and older adults, including individuals with Parkinson's disease, under different upright standing conditions to investigate the potential connection between the temporal structure of variability in postural sway and Parkinsonism. A novel and innovative method called oriented fractal scaling component analysis was employed. This method involves decomposing the two-dimensional center of pressure (CoP) planar trajectories to pinpoint the directions associated with minimal and maximal temporal correlations in postural sway. As a result, it facilitates a comprehensive assessment of the directional characteristics within the temporal structure of sway variability. The results demonstrated that healthy young adults control posture along two orthogonal directions closely aligned with the traditional anatomical anteroposterior (AP) and mediolateral (ML) axes. In contrast, older adults and individuals with Parkinson's disease controlled posture along suborthogonal directions that significantly deviate from the AP and ML axes. These findings suggest that the altered temporal structure of sway variability is evident in individuals with Parkinson's disease and underlies postural deficits, surpassing what can be explained solely by the natural aging process.

Effects of physical exercise interventions on balance, postural stability and general mobility in Parkinson's disease: a network meta-analysis

OBJECTIVE

To assess which type of physical exercise intervention has the most beneficial effects on balance, postural stability and general mobility in patients with Parkinson's disease. These parameters were assessed using the Activities-specific Balance Confidence (ABC) scale, Berg Balance Scale (BBS), Mini-Balance Evaluation Systems Test (MiniBESTest) and Timed Up and Go Test (TUG).

DESIGN

Network meta-analysis.

METHODS

The PubMed, Cochrane Central Register of Controlled Trials, and Web of Science databases were searched up to August 2022 to identify randomized controlled trials on the effects of physical exercise interventions on balance, postural stability, and general mobility. The network meta-analysis included pairwise and indirect comparisons of results on the ABC scale, BBS, MiniBESTest, and TUG across 8 categories of physical exercise.

RESULTS

Eighty-six studies with a total of 4,693 patients were included. For the ABC scale, the indirect comparison showed that the highest effect size was observed for balance vs sensorimotor training without including endurance interventions (0.62; 95% confidence interval (95% CI) 0.06, 1.17). The highest effect sizes for BBS were observed for alternative exercises (1.21; 95% CI 0.62, 1.81), body-weight supported (BWS) interventions (1.31; 95% CI 0.57, 2.05), dance (1.18; 95% CI 0.33, 2.03) and sensorimotor training, including endurance interventions (1.10; 95% CI 0.46, 1.75) vs control groups. Indirect comparisons showed that the highest effect size for the MiniBESTest were observed for balance (0.75; 95% CI 0.46, 1.04) and resistance (0.58; 95% CI 0.10, 1.07) vs control groups. For the TUG, comparisons showed a significant effect size for alternative exercises (-0.54; 95% CI -0.82, -0.26), balance (-0.42; 95% CI -0.75, -0.08), resistance (-0.60; 95% CI -0.89, -0.31), and sensorimotor training including endurance interventions (-0.61; 95% CI -0.95, -0.27) vs control comparisons.

CONCLUSION

Balance interventions improve balance, postural stability, and general mobility in people with Parkinson's disease. Moreover, alternative exercises, dance, BWS interventions, resistance, and sensorimotor training, including and not including endurance interventions, are also effective.

Methods for evaluating gait associated dynamic balance and coordination in rodents

Balance is the dynamic and unconscious control of the body's centre of mass to maintain postural equilibrium. Regulated by the vestibular system, head movement and acceleration are processed by the brain to adjust joints. Several conditions result in a loss of balance, including Alzheimer's Disease, Parkinson's Disease, Menière's Disease and cervical spondylosis, all of which are caused by damage to certain parts of the vestibular pathways. Studies about the impairment of the vestibular system are challenging to carry out in human trials due to smaller study sizes limiting applications of the results and a lacking understanding of the human balance control mechanism. In contrast, more controlled research can be performed in animal studies which have fewer confounding factors than human models and allow specific conditions that affect balance to be replicated. Balance control can be studied using rodent balance-related behavioural tests after spinal or brain lesions, such as the Basso, Beattie and Bresnahan (BBB) Locomotor Scale, Foot Fault Scoring System, Ledged Beam Test, Beam Walking Test, and Ladder Beam Test, which are discussed in this review article along with their advantages and disadvantages. These tests can be performed in preclinical rodent models of femoral nerve injury, stroke, spinal cord injury and neurodegenerative diseases.

Wearable devices for gait and posture monitoring via telemedicine in people with movement disorders and multiple sclerosis: a systematic review

INTRODUCTION

Wearable devices and telemedicine are increasingly used to track health-related parameters across patient populations. Since gait and postural control deficits contribute to mobility deficits in persons with movement disorders and multiple sclerosis, we thought it interesting to evaluate devices in telemedicine for gait and posture monitoring in such patients.

METHODS

For this systematic review, we searched the electronic databases MEDLINE (PubMed), SCOPUS, Cochrane Library, and SPORTDiscus. Of the 452 records retrieved, 12 met the inclusion/exclusion criteria. Data about (1) study characteristics and clinical aspects, (2) technical, and (3) telemonitoring and teleconsulting were retrieved, The studies were quality assessed.

RESULTS

All studies involved patients with Parkinson's disease; most used triaxial accelerometers for general assessment (n = 4), assessment of motor fluctuation (n = 3), falls (n = 2), and turning (n = 3). Sensor placement and count varied widely across studies. Nine used lab-validated algorithms for data analysis. Only one discussed synchronous patient feedback and asynchronous teleconsultation.

CONCLUSIONS

Wearable devices enable real-world patient monitoring and suggest biomarkers for symptoms and behaviors related to underlying gait disorders. thus enriching clinical assessment and personalized treatment plans. As digital healthcare evolves, further research is needed to enhance device accuracy, assess user acceptability, and integrate these tools into telemedicine infrastructure.

PROSPERO REGISTRATION

CRD42022355460.

An improved intermittent control model of postural sway during quiet standing implemented by a data driven approach

This paper proposes a new intermittent control model during human quiet standing, which is consisted of postulated "regular intervention" and "imminent intervention". The regular intervention is within the main control loop, and its trigger condition is equivalent to the switching frequency of center of pressure (COP) data calculated by wavelet transform. The imminent intervention will only be triggered after the postural sway angle exceeds a certain threshold. In order to prove the effectiveness of the new model, the simulation results of the new model and the model proposed by Asai et al. (2009) are compared with the experimental data. The setting parameters of both models are retrieved by Bayesian regression from the experimental data. The results show that the new model not only could exhibit two power law scaling regimes of power spectral density (PSD) of COP, but also show that indices of the probability density function distance, root mean square (RMS), Total Sway Path, displacement Range, 50% power frequency of center of mass (COP) between the simulation results and the experimental data are closer compared to the existing model. Moreover, the limit cycle oscillations (LCOs) obtained from the simulation results of the new model have a higher degree of matching with those retrieved from the experimental data.

Does Impaired Plantar Cutaneous Vibration Perception Contribute to Axial Motor Symptoms in Parkinson's Disease? Effects of Medication and Subthalamic Nucleus Deep Brain Stimulation

OBJECTIVE

To investigate whether impaired plantar cutaneous vibration perception contributes to axial motor symptoms in Parkinson's disease (PD) and whether anti-parkinsonian medication and subthalamic nucleus deep brain stimulation (STN-DBS) show different effects.

METHODS

Three groups were evaluated: PD patients in the medication "on" state (PD-MED), PD patients in the medication "on" state and additionally "on" STN-DBS (PD-MED-DBS), as well as healthy subjects (HS) as reference. Motor performance was analyzed using a pressure distribution platform. Plantar cutaneous vibration perception thresholds (VPT) were investigated using a customized vibration exciter at 30 Hz.

RESULTS

Motor performance of PD-MED and PD-MED-DBS was characterized by greater postural sway, smaller limits of stability ranges, and slower gait due to shorter strides, fewer steps per minute, and broader stride widths compared to HS. Comparing patient groups, PD-MED-DBS showed better overall motor performance than PD-MED, particularly for the functional limits of stability and gait. VPTs were significantly higher for PD-MED compared to those of HS, which suggests impaired plantar cutaneous vibration perception in PD. However, PD-MED-DBS showed less impaired cutaneous vibration perception than PD-MED.

CONCLUSIONS

PD patients suffer from poor motor performance compared to healthy subjects. Anti-parkinsonian medication in tandem with STN-DBS seems to be superior for normalizing axial motor symptoms compared to medication alone. Plantar cutaneous vibration perception is impaired in PD patients, whereas anti-parkinsonian medication together with STN-DBS is superior for normalizing tactile cutaneous perception compared to medication alone. Consequently, based on our results and the findings of the literature, impaired plantar cutaneous vibration perception might contribute to axial motor symptoms in PD.

A non-expensive bidimensional kinematic balance assessment can detect early postural instability in people with Parkinson's disease

Background

Postural instability is a debilitating cardinal symptom of Parkinson’s disease (PD). Its onset marks a pivotal milestone in PD when balance impairment results in disability in many activities of daily living. Early detection of postural instability by non-expensive tools that can be widely used in clinical practice is a key factor in the prevention of falls in widespread population and their negative consequences.

Objective

This study aimed to investigate the effectiveness of a two-dimensional balance assessment to identify the decline in postural control associated with PD progression.

Methods

This study recruited 55 people with PD, of which 37 were men. Eleven participants were in stage I, twenty-three in stage II, and twenty-one in stage III. According to the Hoehn and Yahr (H&amp;Y) rating scale, three clinical balance tests (Timed Up and Go test, Balance Evaluation Systems Test, and Push and Release test) were carried out in addition to a static stance test recorded by a two-dimensional movement analysis software. Based on kinematic variables generated by the software, a Postural Instability Index (PII) was created, allowing a comparison between its results and those obtained by clinical tests.

Results

There were differences between sociodemographic variables directly related to PD evolution. Although all tests were correlated with H&amp;Y stages, only the PII was able to differentiate the first three stages of disease evolution (H&amp;Y I and II: p = 0.03; H&amp;Y I and III: p = 0.00001; H&amp;Y II and III: p = 0.02). Other clinical tests were able to differentiate only people in the moderate PD stage (H&amp;Y III).

Conclusion

Based on the PII index, it was possible to differentiate the postural control decline among the first three stages of PD evolution. This study offers a promising possibility of a low-cost, early identification of subtle changes in postural control in people with PD in clinical practice.

Unveiling the Impact of Outpatient Physiotherapy on Specific Motor Symptoms in Parkinson's Disease: A Prospective Cohort Study

Understanding how outpatient physiotherapy impacts on specific motor symptoms in Parkinson's disease (PD) is important for multidisciplinary care, but these points have not been clarified. We investigated the impact of outpatient physiotherapy on individual motor symptoms in PD patients. Fifty-five PD patients participated in the prospective cohort study, which examined the changes in motor symptoms after 90 min of outpatient physiotherapy program (1×/week for 10 weeks) and at 3 months follow-up. Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor score and tremor, rigidity, bradykinesia, and axial scores were assessed and compared pre-intervention, post-intervention, and at follow-up. Significant level was set at 0.05. Their MDS-UPDRS motor score and axial score significantly decreased post-intervention and at the follow-up. In the analysis differentiating effects based on the severity of motor symptoms according to the MDS-UPDRS motor score, only the moderate-severe group showed significant decreases in their MDS-UPDRS motor score, bradykinesia, and axial scores post-intervention, as well as in their MDS-UPDRS motor score, rigidity, bradykinesia, and axial scores at the follow-up. These findings suggest the outpatient physiotherapy might provide benefits, particularly in managing axial symptoms and bradykinesia, for community dwelling PD patients with moderate-severe motor symptoms within a multidisciplinary care framework.

Do cervical stabilization exercises change the effects of conventional exercises in patients with Parkinson's disease?

OBJECTIVES

The aim of this study was to examine whether cervical stabilization exercises (CSEs) change the effects of conventional exercises (CEs) in patients with PD.

METHODS

Twenty-five patients with PD were randomized into two groups. While the experimental group (EG) received CSEs in addition to CEs, the control group (CG) received only CEs. Both programs lasted 8 weeks. Eighteen participants were able to complete the study. The outcomes were the changes in posture, cervical joint position sense (JPS), balance assessment, 10-m walking tests (10MWT), and the Timed Up & Go (TUG) test.

RESULTS

At the end of the study, significant improvement was observed in both groups in terms of trunk rotation angle and pelvic asymmetry, the time parameter of TUG, and the 10MWT (p < 0.05). In the EG, greater improvement was detected in the Berg Balance Scale, static posturography, postural alignment, JPS, and the cadence parameter of TUG (p < 0.05).

DISCUSSION

CEs and CSEs could improve walking speed and posture in patients with PD, but if CSEs are added to CEs, greater improvements could be achieved in JPS and postural control.(Clinical Trials ID: NCT03854747).

Validity, reliability and minimal detectable change of Mini-BESTest Turkish version in neurological disorders

AIMS

It is aimed to investigate the psychometric properties of Mini-BESTestTR in Turkish patients with neurological disorders.

METHODS

A total of 61 people between the ages of 42 and 80, who were patients with Parkinson's disease, stroke or multiple sclerosis for more than 1 year, were included in the study. For inter-rater reliability, two independent researchers applied the scale two times within 5 days for test-retest reliability. The relationship of mini-BESTestTR with Berg Balance Scale (BBS) to assess concurrent validity, and Timed Get up and Go (TUG), Functional Reach Test (FRT) and Functional Ambulation Classification (FAC) for convergent validity was investigated.

RESULTS

The scores of the two evaluators were within the range of agreement (mean = - 0.278 ± 1.484, p > 0.05), and the Mini-BESTestTR had excellent inter-rater reliability [ICC (95% CI) = 0.989 (0.981-0.993)] and test-retest reliability [ICC (95% CI) = 0.998 (0.996-0.999)]. Mini-BESTestTR had a strong correlation with BBS (r = 0.853, p < 0.001) and TUG (r =  - 0.856, p < 0.001), had a moderate correlation with FAC (r = 0.696, p < 0.001) and FRT (r = 0.650, p < 0.001).

CONCLUSIONS

Mini-BESTestTR showed significant correlations with other balance assessment measures, and concurrent and convergent validity of Mini-BESTestTR was demonstrated when administered to a sample of patients with chronic stroke, Parkinson's disease and multiple sclerosis.

Differences between physical therapist ratings, self-ratings, and posturographic measures when assessing static balance exercise intensity

Introduction

In order for balance therapy to be successful, the training must occur at the appropriate dosage. However, physical therapist (PT) visual evaluation, the current standard of care for intensity assessment, is not always effective during telerehabilitation. Alternative balance exercise intensity assessment methods have not previously been compared to expert PT evaluations. The aim of this study was therefore to assess the relationship between PT participant ratings of standing balance exercise intensity and balance participant self-ratings or quantitative posturographic measures.

Methods

Ten balance participants with age or vestibular disorder-related balance concerns completed a total of 450 standing balance exercises (three trials each of 150 exercises) while wearing an inertial measurement unit on their lower back. They provided per-trial and per-exercise self-ratings of balance intensity on a scale from 1 (steady) to 5 (loss of balance). Eight PT participants reviewed video recordings and provided a total of 1,935 per-trial and 645 per-exercise balance intensity expert ratings.

Results

PT ratings were of good inter-rater reliability and significantly correlated with exercise difficulty, supporting the use of this intensity scale. Per-trial and per-exercise PT ratings were significantly correlated with both self-ratings (r = 0.77-0.79) and kinematic data (r = 0.35-0.74). However, the self-ratings were significantly lower than the PT ratings (difference of 0.314-0.385). Resulting predictions from self-ratings or kinematic data agreed with PT ratings approximately 43.0-52.4% of the time, and agreement was highest for ratings of a 5.

Discussion

These preliminary findings suggested that self-ratings best indicated two intensity levels (i.e., higher/lower) and sway kinematics were most reliable at intensity extremes.

Functional balance training in people with Parkinson's disease: a protocol of balanceHOME randomized control trial with crossover

Introduction

Balance disturbances in Parkinson's Disease (PD) are usually assessed in a single-task as well as standard balance physiotherapy is carried out in isolated environments. Conversely, daily activities are developed in highly challenging environments. Although functional balance training (FBT) is included in the latest protocols, several methodological issues have not yet been considered. In the proposed single-blinded randomized control trial with crossover (NCT04963894), the aims are (1) to quantify the effects achieved by domiciliary FBT (balanceHOME program) in participants with and without cognitive impairment, and (2) to compare them with the effects of a passive-control period and a conventional face-to-face physiotherapy program for PD.

Methods

The initial recruitment was estimated at 112 people with idiopathic PD. Two-thirds of the participants will be randomized to one of the two groups to make the crossover. In contrast, the other third will do a face-to-face group program only. The balanceHOME protocol consists of challenging balance exercises incorporated into functional daily tasks, developed in-home and conducted two times per week for 60-min over an 8-weeks period. The primary strategy will consist of splitting functional tasks of daily life into static and dynamic balance components, besides standardized facilitate and disturbing strategies to execution of each exercise. Biomechanics and clinical performance of balance and gait, perception of quality of life, cognitive and mental functioning, and severity of PD will be measured at baseline (T0), post-8 weeks training (T1), and follow-up (T2).

Results

The primary outcome of the study will be the center of pressure sway area. The secondary outcomes consist of biomechanics and clinical variables related to static and dynamic balance. Outcomes from biomechanical of gait, quality of life, cognitive and mental state, and severity of PD, represent the tertiary outcomes.

Discussion

The balanceHOME program standardizes the FBT in demanding and daily environments for people with PD who prefer individualized treatment from home. This is the first time that the effects of group versus individual balance rehabilitation have been compared in people with and without cognitive impairment and evaluated in complex environments. This still-to-be-finished study will open the possibility of new strategies according to changes in post-pandemic therapeutic approaches.

Anticipatory Postural Adjustments and Compensatory Postural Responses to Multidirectional Perturbations-Effects of Medication and Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease

BACKGROUND

Postural instability is one of the most restricting motor symptoms for patients with Parkinson's disease (PD). While medication therapy only shows minor effects, it is still unclear whether medication in conjunction with deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves postural stability. Hence, the aim of this study was to investigate whether PD patients treated with medication in conjunction with STN-DBS have superior postural control compared to patients treated with medication alone.

METHODS

Three study groups were tested: PD patients on medication (PD-MED), PD patients on medication and on STN-DBS (PD-MED-DBS), and healthy elderly subjects (HS) as a reference. Postural performance, including anticipatory postural adjustments (APA) prior to perturbation onset and compensatory postural responses (CPR) following multidirectional horizontal perturbations, was analyzed using force plate and electromyography data.

RESULTS

Regardless of the treatment condition, both patient groups showed inadequate APA and CPR with early and pronounced antagonistic muscle co-contractions compared to healthy elderly subjects. Comparing the treatment conditions, study group PD-MED-DBS only showed minor advantages over group PD-MED. In particular, group PD-MED-DBS showed faster postural reflexes and tended to have more physiological co-contraction ratios.

CONCLUSION

medication in conjunction with STN-DBS may have positive effects on the timing and amplitude of postural control.

Rehabilitation Interventions for Improving Balance in Parkinson's Disease: A Narrative Review

INTRODUCTION

Postural instability is one of the latest clinical manifestations of Parkinson disease. Because of the limited therapeutic effect of pharmacological therapies, a favorable consideration has now become toward rehabilitation interventions. Thus, this study aimed to synthesize literature evidence to summarize the effects of rehabilitation interventions for improving balance in Parkinson disease.

MATERIALS AND METHODS

We conducted a narrative review of randomized-controlled clinical trials comparing the effects of interventions, control interventions, and no interventions on balance-related outcomes. A comprehensive search using the MEDLINE database was conducted from January 2000 to September 2021. This review included the following causes of balance-related impairments: inability to control body weight in the base of support, impaired attention and focus on balance, postural deformities, proprioceptive deficiency, sensory-motor integration, and coordination disorders, including visual and auditory-motor coordination.

RESULTS

Twenty randomized-controlled clinical trials were included in the review. Various balance-related outcomes were included. The included studies focused on the effectiveness of different rehabilitation interventions, including physical therapy, virtual reality and telerehabilitation, treadmill training, hydrotherapy, action observation training, balance and cues training interventions, and cognitive rehabilitation.

CONCLUSIONS

The results suggest that most of the included rehabilitation interventions have promising therapeutic effects in improving balance in Parkinson disease.

Clinical and MRI features of gait and balance disorders in neurodegenerative diseases

Gait and balance disorders are common signs in several neurodegenerative diseases such as Parkinson's disease, atypical parkinsonism, idiopathic normal pressure hydrocephalus, cerebrovascular disease, dementing disorders and multiple sclerosis. According to each condition, patients present with different gait and balance alterations depending on the structural and functional brain changes through the disease course. In this review, we will summarize the main clinical characteristics of gait and balance disorders in the major neurodegenerative conditions, providing an overview of the significant structural and functional MRI brain alterations underlying these deficits. We also will discuss the role of neurorehabilitation strategies in promoting brain plasticity and gait/balance improvements in these patients.

Validity and Reliability of the Thai Version of the Freezing of Gait Questionnaire in Individuals With Parkinson's disease

OBJECTIVE

To evaluate the validity and reliability of the Thai version of the Freezing of Gait Questionnaire (FOG-Q) in individuals with Parkinson's disease (PD).

METHODS

The FOG-Q was translated into Thai according to the standard process. Fifty-six individuals with PD participated in the study. The content validity was assessed using the content validity index (CVI). The construct validity was evaluated by correlating Thai FOG-Q with Thai version of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) items 2.13 and 3.11, Thai version of the Falls Efficacy Scale-International (FES-I), Timed Up and Go test (TUG) and Berg Balance Scale (BBS) using Spearman's correlation coefficient (rS). The correlation between Thai FOG-Q and clinical characteristics, for example, duration of PD and modified Hoehn and Yahr (mH&Y) stage was evaluated. Internal consistency and test-retest reliability were evaluated with Cronbach's alpha (Cα) and intraclass correlation coefficient (ICC), respectively.

RESULTS

The Thai FOG-Q had high content validity (CVI=0.96). The mean FOG-Q score was 9.0±4.9. The construct validity showed a strong positive correlation with MDS-UPDRS item 2.13 (rS=0.81), and moderate correlations with MDS-UPDRS item 3.11, FES-I, and TUG (rS=0.42-0.60). A negative correlation with BBS was found (rS=-0.32). It had a moderate correlation with mH&Y stage (rS=0.40). The Thai FOG-Q had good internal consistency (Cα=0.87) with excellent test-retest reliability (ICC=0.91).

CONCLUSION

The Thai FOG-Q has excellent validity and reliability. It is a useful instrument for the evaluation of FOG in individuals with PD.

Der Einfluss vom Exergaming mit kommerziell verfügbaren Spielkonsolen auf die Balance und Lebensqualität bei Menschen mit idiopathischem Parkinson-Syndrom – Eine systematische Übersichtsarbeit

Hintergrund Exergaming könnte als Kombination aus Spielspaß und Training ein effektiver Therapie-Ansatz bei Gleichgewichtsstörungen und verminderte Lebensqualität (QoL) bei Parkinson-Patient*innen sein. Zugängliche Arten von Exergaming mit kommerziellen Spielkonsolen wurden bisher nicht umfassend untersucht.

Ziel Untersuchung der Fragestellung, ob Exergaming mit kommerziell verfügbaren Spielkonsolen die Balance und QoL von Patient*innen mit Morbus Parkinson verbessert.

Methode Es erfolgte eine systematische Literaturrecherche in den Datenbanken MEDLINE, Cochrance Library, EMBASE, CINHAL und PEDro. Berücksichtigt wurden Studien, die Patient*innen mit Morbus Parkinson mit kommerziell verfügbaren Exergaming-Konsolen behandelten. Als Messinstrument für Balance wurden „Berg Balance Scale“ (BBS) und „Dynamic Gait Index“ (DGI) festgelegt. Die QoL wurde mittels „Parkinsonʼs Disease Questionnaire“ (PDQ-39) evaluiert. Das Verzerrungsrisikos wurde mithilfe der PEDro-Skala und MINORS eingeschätzt. Die Studienergebnisse wurden tabellarisch zusammengefasst und ausführlich gegenübergestellt.

Ergebnisse Es wurden insgesamt 6 randomisierte kontrollierte Studien sowie 6 Kohortenstudien eingeschlossen. Die Studien umfassten insgesamt 413 Proband*innen, wovon 205 die Exergaming-Intervention erhielten. Die Analyse dieser Studien bestätigte einen positiven Effekt von Exergaming mit kommerziellen Spielkonsolen auf die Balance (BBS, DGI) und QoL (PDQ-39) bei Patient*innen mit Morbus Parkinson im ersten bis dritten Hoehn-und-Yahr-Stadium (H&Y-Stadium).

Schlussfolgerung Exergaming mit kommerziell verfügbaren Spielkonsolen kann zur Verbesserung der Balance und QoL bei Patient*innen mit Morbus Parkinson im H&Y-Stadium 1–3 verwendet werden. Für die Untersuchung des Heim-Exergaming werden weitere Studien benötigt.

The Use of the Static Posturography to Assess Balance Performance in a Parkinson's Disease Population

The literature has shown contradictory results so far about the use of posturography, especially static posturography, to evaluate balance performance in Parkinson’s disease (PD) populations. This study aimed to investigate the use of static posturography as a valid method to evaluate balance in a PD population. Fifty-two participants diagnosed with PD (Hoehn & Yahr stage: 1−3) were included in this cross-sectional study. All participants completed the following assessments: Hoehn and Yahr scale, Movement Disorder Society-Unified Parkinson’s Disease Rating Scale, Tinetti Scale, Berg Balance Scale, Activities-specific Balance Confidence scale, Timed Up and Go test, and Functional Reach Test. Sway parameters were analyzed with a baropodometric platform, under eyes open (EO) and eyes closed (EC) conditions, in a bipodal stance. Small to large correlations were observed between clinical balance tests and static posturography parameters, although the majority of these parameters correlated moderately. Considering posturographic variables, the highest correlation values were detected for total excursion (TE), mean velocity (MV), mean (X-mean), and root-mean-square (X-RMS) displacements in the medio-lateral directions. It was observed that posturographic parameters worsened as the disease progresses, although differences were only significant between the stages 1 and 3 in the H&Y scale (p < 0.05). Regarding the test condition, the visual deprivation worsened significantly all the static posturography parameters (p < 0.05), except the antero-posterior mean displacement (Y-Mean). Comparing visual conditions, the EC presented slightly higher correlation values with the clinical balance tests. Static posturography could be used as an objective complementary tool to clinical balance tests in order to assess and control balance performance, mainly to detect postural instability problems.

Association of Depression With Early Occurrence of Postural Instability in Parkinson's Disease

OBJECTIVE

Depression in Parkinson's disease (PD) affects the quality of life of patients. Postural instability and gait disturbance are associated with the severity and prognosis of PD. We investigated the association of depression with axial involvement in early-stage PD patients.

METHODS

This study involved 95 PD patients unexposed to antiparkinsonian drugs. After a baseline assessment for depression, the subjects were divided into a depressed PD group and a nondepressed PD group. Analyses were conducted to identify an association of depression at baseline with the following outcome variables: the progression to Hoehn and Yahr scale (H-Y) stage 3, the occurrence of freezing of gait (FOG), levodopa-induced dyskinesia, and wearing-off. The follow-up period was 53.40 ± 16.79 months from baseline.

RESULTS

Kaplan-Meier survival curves for H-Y stage 3 and FOG showed more prominent progression to H-Y stage 3 and occurrences of FOG in the depressed PD group than in the nondepressed PD group (log-rank p = 0.025 and 0.003, respectively). Depression in drug-naïve, early-stage PD patients showed a significant association with the progression to H-Y stage 3 (hazard ratio = 2.55; 95% confidence interval = 1.32-4.93; p = 0.005), as analyzed by Cox regression analyses. In contrast, the occurrence of levodopa-induced dyskinesia and wearing-off did not differ between the two groups (log-rank p = 0.903 and 0.351, respectively).

CONCLUSION

Depression in drug-naïve, early-stage PD patients is associated with an earlier occurrence of postural instability. This suggests shared nondopaminergic pathogenic mechanisms and potentially enables the prediction of early development of postural instability.

Effects of Oral Levodopa on Balance in People with Idiopathic Parkinson's Disease

BACKGROUND

Balance impairment is a frequent cause of morbidity and mortality in people with Parkinson's disease (PD). As opposed to the effects of appendicular motor symptoms, the effects of Levodopa on balance impairment in idiopathic PD are less clear.

OBJECTIVE

To review the literature on the effects of oral Levodopa on clinical balance test performance, posturography, step initiation, and responses to perturbation in people with idiopathic PD (PwPD).

METHODS

A systematic search of three scientific databases (Pubmed, Embase, and Web of Science) was conducted in accordance with PRISMA guidelines. For the pilot meta-analysis, standardized mean differences with 95% confidence intervals were calculated using an inverse variance random effects model. Data not suitable for implementation in the meta-analysis (missing means or standard deviations, and non-independent outcomes) were analyzed narratively.

RESULTS

A total of 2772 unique studies were retrieved, of which 18 met the eligibility criteria and were analyzed, including data of 710 idiopathic PwPD. Levodopa had a significant positive effect on the Berg Balance Scale, the Push and Release test, and jerk and frequency parameters during posturography. In contrast, some significant negative effects on velocity-based sway parameters were found during posturography and step initiation. However, Levodopa had no significant effect on most step initiation- and all perturbation parameters.

CONCLUSION

The effects of Levodopa on balance in PwPD vary depending on the outcome parameters and patient inclusion criteria. A systematic approach with well-defined outcome parameters, and prespecified, sensitive and reliable tests is needed in future studies to unravel the effects of oral Levodopa on balance.

Short-Term Motor Outcomes in Parkinson’s Disease after Subthalamic Nucleus Deep Brain Stimulation Combined with Post-Operative Rehabilitation: A Pre-Post Comparison Study

Background

The effects of subthalamic nuclear deep brain stimulation therapy (STN-DBS) and combined postoperative rehabilitation for patients with Parkinson's disease with postural instability have yet to be well reported. This study investigated the effects of short-term postoperative rehabilitation with STN-DBS on physical function in patients with Parkinson's disease.

Methods

Patients diagnosed with Parkinson's disease who were admitted to our hospital for STN-DBS surgery were included in this study. Data were prospectively collected and retrospectively analyzed. Postoperative rehabilitation consisted of muscle-strengthening exercises, stretching, and balance exercises for 40–60 minutes per day for approximately 14 days. The Mini-Balance Evaluation Systems Test (Mini-BESTest), Timed Up and Go test (TUG) seconds and steps, Trunk Impairment Scale (TIS), seconds for 10 times toe-tapping, lower limb extension torque using StrengthErgo240, and center of pressure sway in the quiet standing posture were evaluated preoperatively, postoperatively, and at discharge. Mini-BESTest changes were also evaluated in the two groups classified by the presence or absence of postural instability. One-way and two-way repeated measures analyses of variance were performed for each of the three periods of change, and paired t-tests with the Bonferroni method were performed as multiple comparison tests. A stepwise multiple regression model was used to identify factors associated with balance improvement.

Results

A total of 60 patients with Parkinson's disease were included, and there were significant increases in Mini-BESTest, TIS, StrengthErgo240, and postural sway during closed-eye standing compared to pre- and postoperative conditions at discharge (p < 0.05), and they decreased significantly compared to the postoperative period (p < 0.05). On stepwise multiple regression analysis, decreased steps of TUG and improvement of TIS scores were related to improvement of the Mini-BESTest (p < 0.05). In addition, Mini-BESTest scores in both groups with and without postural instability were significantly increased at discharge compared to preoperative and postoperative conditions (p < 0.01).

Conclusion

Postoperative rehabilitation combined with STN-DBS may provide short-term improvements in physical function compared with the preoperative medicated status. The improvements in gait step length and trunk function may be important factors for obtaining improvement of postoperative postural stability.

Rasch Validation of the Mini-BESTest in People With Parkinson Disease

BACKGROUND AND PURPOSE

The Mini-BESTest is a balance measure with robust psychometric properties widely used in people with Parkinson disease. The aim of this study was to examine-with advanced psychometric techniques-some key properties of the Mini-BESTest (including unidimensionality, functioning of rating categories, internal construct validity, reliability indexes) in a consecutive sample of individuals with Parkinson disease admitted for balance rehabilitation.

METHODS

Confirmatory factor analysis and Rasch analysis (partial credit model) were performed on 193 individual raw scores of the Mini-BESTest items.

RESULTS

Confirmatory factor analysis fit indices and principal component analysis of the residuals confirmed the scale's unidimensionality. At Rasch analysis, the 3-level rating scale demonstrated appropriate functioning. All items fitted the Rasch model. Item response dependence was negligible. No differential item functioning was found across gender and age groups.

DISCUSSION AND CONCLUSIONS

We confirmed and extended the evidence (demonstrated in different populations) on the general psychometric soundness of the Mini-BESTest, even when tested with rigorous statistical methods. In addition, 2 forms were created: (i) to transform raw scores into linear estimates of dynamic balance; and (ii) to compare the individual's item responses with those expected by the Rasch model (thus providing an aid for tailored interventions) and manage missing responses. Further independent studies using advanced psychometric techniques are warranted, also in people with balance disturbances of different etiology. Our study further increases the confidence in using the Mini-BESTest to assess dynamic balance in people with Parkinson disease and provides some useful additional clinical aids for interpreting the results and calculating more precise change scores.See the Supplementary Video, available at: http://links.lww.com/JNPT/A384.

Dancing With Parkinson's Disease: The SI-ROBOTICS Study Protocol

Introduction: Parkinson's disease (PD) is one of the most frequent causes of disability among older people, characterized by motor disorders, rigidity, and balance problems. Recently, dance has started to be considered an effective exercise for people with PD. In particular, Irish dancing, along with tango and different forms of modern dance, may be a valid strategy to motivate people with PD to perform physical activity. The present protocol aims to implement and evaluate a rehabilitation program based on a new system called “SI-ROBOTICS,” composed of multiple technological components, such as a social robotic platform embedded with an artificial vision setting, a dance-based game, environmental and wearable sensors, and an advanced AI reasoner module.

Methods and Analysis: For this study, 20 patients with PD will be recruited. Sixteen therapy sessions of 50 min will be conducted (two training sessions per week, for 8 weeks), involving two patients at a time. Evaluation will be primarily focused on the acceptability of the SI-ROBOTICS system. Moreover, the analysis of the impact on the patients' functional status, gait, balance, fear of falling, cardio-respiratory performance, motor symptoms related to PD, and quality of life, will be considered as secondary outcomes. The trial will start in November 2021 and is expected to end by April 2022.

Discussions: The study aims to propose and evaluate a new approach in PD rehabilitation, focused on the use of Irish dancing, together with a new technological system focused on helping the patient perform the dance steps and on collecting kinematic and performance parameters used both by the physiotherapist (for the evaluation and planning of the subsequent sessions) and by the system (to outline the levels of difficulty of the exercise).

Ethics and Dissemination: The study was approved by the Ethics Committee of the IRCCS INRCA. It was recorded in ClinicalTrials.gov on the number NCT05005208. The study findings will be used for publication in peer-reviewed scientific journals and presentations in scientific meetings.

Therapeutic Implications of Caffeic Acid in Cancer and Neurological Diseases

Caffeic acid (CA) is found abundantly in fruits, vegetables, tea, coffee, oils, and more. CA and its derivatives have been used for many centuries due to their natural healing and medicinal properties. CA possesses various biological and pharmacological activities, including antioxidant, anti-inflammatory, anticancer, and neuroprotective effects. The potential therapeutic effects of CA are mediated via repression and inhibition of transcription and growth factors. CA possesses potential anticancer and neuroprotective effects in human cell cultures and animal models. However, the biomolecular interactions and pathways of CA have been described highlighting the target binding proteins and signaling molecules. The current review focuses on CA's chemical, physical, and pharmacological properties, including antioxidant, anti-inflammatory, anticancer, and neuroprotective effects. We further described CA's characteristics and therapeutic potential and its future directions.

Acceptability and Preliminary Results of Technology-Assisted Balance Training in Parkinson's Disease

(1) Background: Parkinson’s Disease (PD) is one of the most common causes of disability among older individuals. The advanced stages of PD are usually characterized by postural instability and, as a consequence, falls. Those are among the main factors that determine the quality of life, as well as the morbidity and mortality of a person with PD. In the field of PD rehabilitation, robotics is also rapidly gaining ground. As a primary aim, we evaluate the acceptability of the technology integrated intervention, using the Psychosocial Impact of Assistive Devices Scale (PIADS), in order to analyze the attitude of the participants towards the Tymo^® system. As a secondary outcome, we assess the result of the rehabilitation treatment integrated with the Tymo^® system on several patient’s features. (2) Methods: We studied a population of 16 patients with Parkinson’s Disease. Each recruited subject completed 10 treatment sessions, organized as two training sessions per week, for 5 weeks. The intervention included 30 min of traditional therapy and 20 min of technological treatment with a robotic system. PIADS is composed of three subscales (Competence subscale, Adaptability subscale, Self-esteem subscale) ranging from −3 to +3, reflecting, respectively, a negative or positive feeling towards the device. (3) Results: The Competence subscale, measuring feelings of competence and usefulness, obtained a score of 1.24 (SD = 0.78). The score of Adaptability subscale, indicating a willingness to try out new things and to take risks, was 1.83 (SD = 0.65). Finally, the Self-esteem subscale, indicating feelings of emotional health and happiness, reached a score of 1.31 (SD = 0.72). Moreover, statistical analysis reveals a significant effect on balance performance after intervention. (4) Conclusions: This feasibility study represents a starting point in the use of technology in the rehabilitation pathway of patients affected by Parkinson’s Disease. In fact, our results suggest that a standard therapy combined with an innovative treatment using Tymo^® may be accepted by PD patients, which may benefit especially from preserving balance.

Avaliação do risco de quedas entre pessoas com doença de Parkinson

RESUMO Objetivo identificar os fatores associados ao risco de quedas entre as pessoas com doença de Parkinson cadastradas na Associação Parkinson Santa Catarina. Método estudo transversal exploratório descritivo e de abordagem quantitativa, realizado com 53 pessoas cadastradas na Associação Parkinson Santa Catarina, no município de Florianópolis, Brasil, no período de junho a setembro de 2019. Foram aplicados questionário sociodemográfico, Escala de Hoehn e Yahr, Mini Exame do Estado Mental e Teste de Rastreio do Risco de Queda no Idoso. Os dados foram tabulados e analisados por meio do Sistema online de Ensino-Aprendizagem de Estatística SEstatNet®. Resultados foram identificados fatores de risco, como sexo, aumento da idade, redução da força muscular, instabilidade postural e diminuição da velocidade da marcha. Em relação aos estágios da doença, foi constatado que em todos houve piora da velocidade da marcha e o medo de cair é constante, aumentando com o agravamento da doença e o tempo de diagnóstico. Conclusão e implicações para a prática ao aprofundar o estudo do tema, o enfermeiro consegue compreender os acometimentos motores que levam à fragilização e à queda em pessoas com doença de Parkinson, elaborando estratégias para preveni-las.

The effect of Tai Chi on functional mobility, balance and falls in Parkinson's disease: A systematic review and meta-analysis of systematic reviews

BACKGROUND

The aim of the study was to evaluate the effect of Tai Chi on functional mobility, balance and falls in Parkinson's disease.

MATERIALS AND METHODS

A comprehensive literature search was conducted to identify the systematic reviews and meta-analyses up to the end of October 2021. 601 studies were identified, and 16 of them were included in our study.

RESULTS

According to our meta-analysis; there was a significant effect of Tai Chi on balance (SMD, -0.777 95% CI -0.921 to -0.633; p = 0.000), functional mobility (SMD, -0.719 95% CI -0.944 to -0.494; p = 0.000), and falls (SMD, -0.456 95% CI -0.668 to -0.245; p = 0.000) in PD.

CONCLUSION

Our systematic review and meta-analysis found significant effects of Tai Chi on functional mobility, balance and falls in patients with PD.

Cholinesterase inhibitors for gait, balance, and fall in Parkinson disease: a meta-analysis

Gait disturbance and imbalance are the major symptoms of Parkinson disease (PD), with fall being the most undesirable consequence. However, few effective evidence-based treatments are available for alleviating these symptoms and preventing falls. Cholinesterase inhibitors (ChEIs) are a well-established treatment for PD dementia with possible impacts on gait, balance, and fall reduction. The present study involved a meta-analysis of randomized controlled trials (RCTs) to investigate the effects of ChEIs on gait, balance, and fall in patients with PD. We searched for studies using the PubMed, Embase, and Web of Science databases. The major outcomes were effects on gait parameters, balance, and fall. This study was registered with PROSPERO (CRD42021254733). Five RCTs were included in the present meta-analysis. ChEIs did not significantly increase gait speed in PD patients (mean difference [MD]: 0.03 m/s, 95% confidence interval [CI]: -0.02 to 0.07, p = 0.29). However, ChEI treatment significantly decreased step or stride variability during the single task (standard MD: -0.43, 95% CI = -0.79 to -0.06, p = 0.02). Regarding fall and balance, trending but nonsignificant beneficial effects were observed with ChEI treatment. In conclusion, although ChEI treatment did not significantly improve gait speed and reduce fall, it can significantly reduce step or stride variability. Considering that gait disorder is a challenging issue in patients with PD and that ChEIs are generally tolerable, the present meta-analysis may provide more evidence for the benefit of ChEIs on PD gait disturbance as an alternative treatment consideration.

Influence of radial optic flow stimulation on static postural balance in Parkinson's disease: A preliminary study

The role of optic flow in the control of balance in persons with Parkinson's disease (PD) has yet to be studied. Since basal ganglia are understood to have a role in controlling ocular fixation, we have hypothesized that persons with PD would exhibit impaired performance in fixation tasks, i.e., altered postural balance due to the possible relationships between postural disorders and visual perception. The aim of this preliminary study was to investigate how people affected by PD respond to optic flow stimuli presented with radial expanding motion, with the intention to see how the stimulation of different retinal portions may alter the static postural sway. We measured the body sway using center of pressure parameters recorded from two force platforms during the presentation of the foveal, peripheral and full field radial optic flow stimuli. Persons with PD had different visual responses in terms of fixational eye movement characteristics, with greater postural alteration in the sway area and in the medio-lateral direction than the age-matched control group. Balance impairment in the medio-lateral oscillation is often observed in persons with atypical Parkinsonism, but not in Parkinson's disease. Persons with PD are more dependent on visual feedback with respect to age-matched control subjects, and this could be due to their impaired peripheral kinesthetic feedback. Visual stimulation of standing posture would provide reliable signs in the differential diagnosis of Parkinsonism.

Correlation between community balance and mobility scale (CB&M) with a battery of outcome measures to assess balance in Parkinson's disease - a cross-sectional study

BACKGROUND

Evaluating balance in a functional context that integrates challenging tasks frequently performed in the community is essential to identify community-dwelling individuals who are at risk of falls in early Parkinson Disease (PD) than a simple balance measure. Community Balance and Mobility (CB&M) scale is one such measure that evaluates severe deficits in gait, balance, and mobility. The risk of falling and fear of fall is common among PD individuals and this affects the day to day functioning as well as the quality of life. Early identification of individuals who may be at risk to fall will lead to intervention strategies that can help to with balance issues. The aim of this study was to correlate between Community Balance and Mobility with a battery of outcome measures commonly used to assess balance in Parkinson's disease.

METHODS

A cross sectional study design; with individuals referred to Outpatient physiotherapy department, diagnosed with idiopathic Parkinson's disease, independently mobile and on a stable drug regimen referred by the neurologist; were screened and recruited by convenience sampling. With written informed consent, demographic data gathered and scales such as Berg Balance scale, Community balance & mobility scale, Functional Reach test and Timed up and go test were administered with an ample amount of rest.

RESULTS

The results obtained were documented and analysed using Karl Pearson's correlation coefficient. Significant correlation between CB&M and BBS (r = 0.795) was found, CB&M and TUG (r = - 0.755), CB&M and FRT (r = 0.772).

CONCLUSION

CB&M is a useful measure which integrates items that challenge balance in the community context. It has been used to assess high functioning community dwelling individuals and hence may be apt for individuals with early Parkinson's, since the tasks to be performed in CB&M are challenging and these simulate community level activities where the risk of falls is higher. It may well be a good tool to assess early Parkinson's; their level of balance, community level activity and without need for sophisticated & expensive equipment.

Development of a Parkinson's disease specific falls questionnaire

BACKGROUND

Falls are a major health burden for older adults with Parkinson's disease (PD), but there is currently no reliable questionnaire to capture the circumstances and consequences of falls in older adults with PD. This study aimed to develop a PD-specific falls questionnaire and to evaluate its test-retest reliability in older adults with PD.

METHODS

A novel PD-specific falls questionnaire (PDF-Q) was developed in two modes (online and paper-based version) and used to assess falls and near-falls events over the past 12-months. Questions were agreed upon by an expert group, with the domains based on previous falls-related questionnaires. The questions included the number and circumstances (activities, location and direction) of falls and near-falls, and consequences (injuries and medical treatment) of falls. The PDF-Q was distributed to 46 older adults with PD (online n = 30, paper n = 16), who completed the questionnaire twice, 4 weeks apart. Kappa (κ) statistics were used to establish test-retest reliability of the questionnaire items.

RESULTS

Pooled results from both questionnaires for all participants were used to assess the overall test-retest reliability of the questionnaire. Questions assessing the number of falls (κ = 0.41) and the number of near-falls (κ = 0.51) in the previous 12-months demonstrated weak agreement, while questions on the location of falls (κ = 0.89) and near-falls (κ = 1.0) demonstrated strong to almost perfect agreement. Questions on the number of indoor (κ = 0.86) and outdoor (κ = 0.75) falls demonstrated moderate to strong agreement, though questions related to the number of indoor (κ = 0.47) and outdoor (κ = 0.56) near-falls demonstrated weak agreement. Moderate to strong agreement scores were observed for the most recent fall and near-fall in terms of the direction (indoor fall κ = 0.80; outdoor fall κ = 0.81; near-fall κ = 0.54), activity (indoor fall κ = 0.70; outdoor fall κ = 0.82; near-fall κ = 0.65) and cause (indoor fall κ = 0.75; outdoor fall κ = 0.62; near-fall κ = 0.56).

CONCLUSIONS

The new PDF-Q developed in this study was found to be reliable for capturing the circumstances and consequences of recent falls and near-falls in older adults with PD.

Comparison of the effect of whole-body vibration therapy versus conventional therapy on functional balance of patients with Parkinson's disease: adding a mixed group

OBJECTIVE

Assess the effect of Whole-Body Vibration (WBV) therapy in functional balance status of Parkinson's disease (PD) patients and compare this to conventional and combined therapy.

INTRODUCTION

PD patients experience a decreased mobility, inactivity, and loss of independence as consequence of disturbances in gait, posture, and balance. Rehabilitation therapy is a non-pharmacological way of improving functionality. One of the most studied modalities is WBV, with multiple studies showing improvement in motor function. However, results in this manner are inconsistent.

METHODS

Forty-five patients were enrolled in a non-randomized controlled trial and divided into three groups. Group 1 received conventional therapy (thermotherapy, stretching, strengthening, coordination and balance). Group 2 received WBV therapy, and group 3 patients underwent a combined therapy protocol. A total of 20 sessions (3 per week) were conducted, assessing Berg Balance Scale (BBS) before initial and after final session.

RESULTS

The 3 intervention groups showed significant improvement in BBS scores after concluding the 20-session trial compared to initial assessment. When comparing mean change in BBS score from initial to final assessment, the combined therapy group had a greater increase compared to conventional therapy, but no significant differences were observed comparing to WBV group. Mean change in BBS score showed no significant difference between conventional therapy and WBV therapy group.

CONCLUSIONS

WBV therapy is a useful tool as co-adjuvant in conventional therapy. The combination of both therapies is a significant therapeutic alternative for the improvement of functional balance status in PD patients compared to conventional therapy alone.

Abnormal center of mass feedback responses during balance: A potential biomarker of falls in Parkinson's disease

Although Parkinson disease (PD) causes profound balance impairments, we know very little about how PD impacts the sensorimotor networks we rely on for automatically maintaining balance control. In young healthy people and animals, muscles are activated in a precise temporal and spatial organization when the center of body mass (CoM) is unexpectedly moved that is largely automatic and determined by feedback of CoM motion. Here, we show that PD alters the sensitivity of the sensorimotor feedback transformation. Importantly, sensorimotor feedback transformations for balance in PD remain temporally precise, but become spatially diffuse by recruiting additional muscle activity in antagonist muscles during balance responses. The abnormal antagonist muscle activity remains precisely time-locked to sensorimotor feedback signals encoding undesirable motion of the body in space. Further, among people with PD, the sensitivity of abnormal antagonist muscle activity to CoM motion varies directly with the number of recent falls. Our work shows that in people with PD, sensorimotor feedback transformations for balance are intact but disinhibited in antagonist muscles, likely contributing to balance deficits and falls.

Establishing the Rotenone-Induced Parkinson's Disease Animal Model in Wistar Albino Rats

Objective The aim of this study was to establish the safe and effective dose of rotenone-induced Parkinson’s disease (PD) in Wistar albino rat.

Materials and Methods Male Wistar albino rats (n = 6) aged between 9 and 11 weeks, weight 200 to 250 g, were selected for the study. Rats were divided into four groups namely, A, B, C, and D; Group A served as control received only isotonic saline, groups B, C, and D were administered with rotenone 2, 2.5, and 3 mg/kg body weight (BW), respectively, with a specialized vehicle through intraperitoneal (IP) route once daily. During the procedure, they were observed for the development of the PD signs such as stooped posture, postural instability, akinesia, bradykinesia, and muscular rigidity. BW and behavioral pattern were recorded before the rotenone introduction and also after the onset of PD signs in them. They were sacrificed when the PD phenotype became debilitating and followed by neurochemical assay for dopamine and antioxidants; histological assay for TH-neuronal density and Lewy bodies were performed in the substantia nigra pars compacta (SNpc) of midbrain.

Results Group C and D animals were developed with the PD signs by the 9th day and also there was a significant decrease in the BW noticed in them. Additionally, histological studies revealed the decrease in neuronal density and the presence of Lewy bodies in the dopamine neurons of the SNpc. However, it was also noticed that the group D had shown more mortality rate when compared with the Group C.

Conclusion Rotenone with 2.5 mg/kg BW IP was an ideal dose to develop PD signs in Wistar albino rats model that is a highly reproducible and may offer an excellent tool to establish the new neuroprotective treatment strategies.

Does the impaired postural control in Parkinson's disease affect the habituation to non-sequential external perturbation trials?

BACKGROUND

How people with Parkinson's disease habituate their postural response to unpredictable translation perturbation is not totally understood. We compared the capacity to change the postural responses after unexpected external perturbation and investigated the habituation plateaus of postural responses to non-sequential perturbation trials in people with Parkinson's disease and healthy older adults.

METHODS

In people with Parkinson's disease (n = 37) and older adults (n = 20), sudden posterior support-surface translational were applied in 7 out of 17 randomized trials to ensure perturbation unpredictability. Electromyography and center of pressure parameters of postural response were analyzed by ANOVAs (Group vs. Trials). Two simple planned contrasts were performed to determine at which trial the responses first significantly habituate, and by which trials the habituation plateaus.

FINDINGS

Older adults demonstrated a first response change in trial 5 and habituation plateaus after trial 4, while for people with Parkinson's disease, the first change occurred in trial 2 and habituation plateau after trial 5 observed by center of pressure range. People with Parkinson's disease demonstrated a greater center of pressure range in trial 1 compared to older adults. Independent of trial, people with Parkinson's disease vs. older adults demonstrated a greater ankle muscle co-activation and recovery time.

INTERPRETATION

Despite the greater center of pressure range in the first trial, people with Parkinson's disease can habituate to unpredictable perturbations. This is reflected by little, to no difference in the time-course of adaptation for all but 2 parameters that showed only marginal differences between people with Parkinson's disease and older adults.

The relationship between attention and static balance disturbance in patients with Parkinson's disease

OBJECTIVE

Balance disturbance is one of the main complications of the Parkinson's disease (PD). As studies have shown that impairments in some cognitive processes can lead to balance problems, we investigated the relationship between focused and divided attention and static balance in patients with PD and a healthy control group.

METHODS

We included 111 patients with PD (M age = 49.41, SD = 6.33 years) and 142 healthy individuals (M age = 50.62, SD = 6.07 years). All participants were evaluated with the Trails Making Test A and B (TMT), and all participants' balance was evaluated with a Wii Balance Board, from which we measured the antero-posterior (AP), medio-lateral (ML), and total center of pressure (COP) velocity. We compared the two groups in terms of TMT-A, TMT-B, and COP velocity tests in both eyes-open and eyes-closed conditions with independent t-tests, and we calculated Pearson's correlation coefficients between the balance board-derived outcomes and the TMT scores.

RESULTS

The two groups differed significantly on TMT-A and TMT-B scores, in total and ML COP velocity in both eyes-closed and eyes-open conditions, and in AP COP velocity only in eyes-open condition. Among patients with PD, TMT-A and TMT-B scores were positively correlated with total, ML, and AP COP velocity, in both eyes-open and eyes-closed conditions.

CONCLUSIONS

Associated attention deficits may be among the causes of balance disturbances in patients with PD, though both attention and balance may have a common root in brain circuitry.