Early Screening for the Parkinson Variant of Multiple System Atrophy: A 6-Item Score

BACKGROUND

A 4-item score based on ≥2 features out of orthostatic hypotension, overactive bladder, urinary retention and postural instability was previously shown to early distinguish the Parkinson-variant of multiple system atrophy (MSA-P) from Parkinson's disease (PD) with 78% sensitivity and 86% specificity.

OBJECTIVES

To replicate and improve the 4-item MSA-P score.

METHODS

We retrospectively studied 161 patients with early parkinsonism [ie, ≤2 years disease duration or no postural instability, aged 64 (57; 68) years, 44% females] and a diagnosis of clinically established MSA-P (n = 38) or PD (n = 123) after ≥24 months follow-up.

RESULTS

The 4-item MSA-P score had a 92% sensitivity and 78% specificity for a final MSA-P diagnosis. By including dopaminergic responsiveness and postural deformities into a 6-item score (range: 0-6), reaching ≥3 points at early disease identified MSA-P patients with 89% sensitivity and 98% specificity.

CONCLUSIONS

The 6-item MSA-P score is a cost-effective tool to pinpoint individuals with early-stage MSA-P.

Clinicopathological study of dementia with grains presenting with parkinsonism compared with a typical case

Argyrophilic grain disease (AGD) is one of the major pathological backgrounds of senile dementia. Dementia with grains refers to cases of dementia for which AGD is the sole background pathology responsible for dementia. Recent studies have suggested an association between dementia with grains and parkinsonism. In this study, we aimed to present two autopsy cases of dementia with grains. Case 1 was an 85-year-old man who exhibited amnestic dementia and parkinsonism, including postural instability, upward gaze palsy, and neck and trunk rigidity. The patient was clinically diagnosed with progressive supranuclear palsy and Alzheimer's disease. Case 2 was a 90-year-old man with pure amnestic dementia, clinically diagnosed as Alzheimer's disease. Recently, we used cryo-electron microscopy to confirm that the tau accumulated in both cases had the same three-dimensional structure. In this study, we compared the detailed clinical picture and neuropathological findings using classical staining and immunostaining methods. Both cases exhibited argyrophilic grains and tau-immunoreactive structures in the brainstem and basal ganglia, especially in the nigrostriatal and limbic systems. However, Case 1 had more tau immunoreactive structures. Considering the absence of other disease-specific structures such as tufted astrocytes, astrocytic plaques and globular glial inclusions, lack of conspicuous cerebrovascular disease, and no history of medications that could cause parkinsonism, our findings suggest an association between AGD in the nigrostriatal system and parkinsonism.

Metronidazole-Induced Acute Cerebellitis in a Young Patient: Unusual Onset, Delayed Remission, and Characteristic Imaging Features

Metronidazole-induced acute cerebellitis is an exceptionally rare condition resulting from severe adverse reactions to metronidazole, a medication generally employed in the management of infections caused by anaerobic microbes. Although neuropathy has been linked to metronidazole use, reports of acute cerebellitis are infrequent. The neurological effects associated with metronidazole can include weakness, dysarthria, postural instability, seizures, giddiness, vertigo, ataxia, confusion, encephalopathy, headaches, and tremors. The onset of cerebellitis can vary, occurring as early as one day or after several weeks of metronidazole treatment. This article presents a case of a young girl who presented to us with weakness in both upper and lower limbs, dysarthria, and postural instability after exposure to 12 grams of metronidazole (suicidal, 30 tablets of 400 mg). With the above-mentioned complaints, the patient was advised of magnetic resonance imaging of the brain, which showed the features of cerebellitis.

The Effect of Visual Impairment on Postural Stability After Lumbar Spine Fracture: A Case Report and Review of the Literature

The role of vision in maintaining postural stability is crucial, and its loss, whether congenital or acquired, can significantly impact sensory-motor interactions, leading to musculoskeletal abnormalities and defective gait patterns. This case report discusses the complex interplay between visual impairment, post-traumatic kyphosis, and the development of spinal deformity in a 79-year-old blind patient. The patient sustained a simple fall resulting in an L1 compression fracture in 2016. Despite conservative treatment for the fracture, progressive spinal deformity became evident both clinically and radiographically. Further assessments, including evaluation of bone healing, facet arthroplasty, disc degeneration, and canal compromise, were performed. The patient's altered gait and postural abnormalities were indicative of the impact of visual impairment on postural stability. After addressing osteoporosis through endocrinology consultation and medical management, the patient underwent posterior spinal instrumentation and deformity correction, leading to a successful post-operative recovery with a return to baseline functional status. Visual impairment disrupts postural stability by limiting sensory input and prompting compensatory mechanisms, which may increase postural sway and instability. This abnormal gait further contributes to spinal deformities, and the fear of falling can exacerbate postural instability, limiting mobility. Over time, persistent postural imbalance leads to the creation of a state of continual asymmetric stress related to the spinal axis, which can progress to the development of spinal deformities, creating a self-perpetuating cycle.  This case underscores the significance of vision in postural stability and the adverse effects of visual impairment on spinal alignment. The development of spinal deformities in visually impaired individuals, especially in the presence of risk factors like osteoporosis, emphasizes the need for early intervention and postural training to prevent irreversible deformities. Decisions regarding surgical or non-surgical interventions for spinal deformities in visually impaired patients must consider multiple factors, including clinical symptoms, appearance, pain, functional limitations, and social issues. Future research should explore effective interventions for improving postural stability in visually impaired individuals and preventing the development of spinal deformity.

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&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&Y stages, only the PII was able to differentiate the first three stages of disease evolution (H&Y I and II: p = 0.03; H&Y I and III: p = 0.00001; H&Y II and III: p = 0.02). Other clinical tests were able to differentiate only people in the moderate PD stage (H&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.

A Deep Learning Approach for Automatic and Objective Grading of the Motor Impairment Severity in Parkinson's Disease for Use in Tele-Assessments

Wearable sensors provide a tool for at-home monitoring of motor impairment progression in neurological conditions such as Parkinson's disease (PD). This study examined the ability of deep learning approaches to grade the motor impairment severity in a modified version of the Movement Disorders Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) using low-cost wearable sensors. We hypothesized that expanding training datasets with motion data from healthy older adults (HOAs) and initializing classifiers with weights learned from unsupervised pre-training would lead to an improvement in performance when classifying lower vs. higher motor impairment relative to a baseline deep learning model (XceptionTime). This study evaluated the change in classification performance after using expanded training datasets with HOAs and transferring weights from unsupervised pre-training compared to a baseline deep learning model (XceptionTime) using both upper extremity (finger tapping, hand movements, and pronation-supination movements of the hands) and lower extremity (toe tapping and leg agility) tasks consistent with the MDS-UPDRS. Overall, we found a 12.2% improvement in accuracy after expanding the training dataset and pre-training using max-vote inference on hand movement tasks. Moreover, we found that the classification performance improves for every task except toe tapping after the addition of HOA training data. These findings suggest that learning from HOA motion data can implicitly improve the representations of PD motion data for the purposes of motor impairment classification. Further, our results suggest that unsupervised pre-training can improve the performance of motor impairment classifiers without any additional annotated PD data, which may provide a viable solution for a widely deployable telemedicine solution.

Unraveling the Twist: Spatial Navigational Challenges in Cervical Dystonia

BACKGROUND

Cervical dystonia (CD) is an intricate neurological condition with motor and nonmotor symptoms. These include disruptions in visual perception, self-orientation, visual working memory, and vestibular functions. However, the specific impact of CD on perceiving self-motion direction, especially with isolated visual or vestibular stimuli, remains largely unexplored.

OBJECTIVE

This study aimed to examine the effects of CD on linear motion perception, hypothesizing impaired heading discrimination in both vestibular and visual tasks, and that such deficits correlate with the disease severity.

METHODS

We employed a cutting-edge motion platform to precisely control whole-body linear motion. Through repeated two-alternative forced-choice tasks, we assessed vestibular heading direction discrimination. Participants observed dynamic star clouds in immersive virtual reality and indicated their perceived self-motion direction, evaluating visual heading direction discrimination. Sensitivity to direction variations and response accuracy errors were analyzed using robust Gaussian cumulative distribution psychometric functions.

RESULTS

Heading perception is impaired in individuals with CD, particularly evident in vestibular heading discrimination. CD severity correlated with elevated thresholds for both vestibular and visual heading discrimination. Surprisingly, lateralized CD did not introduce bias in either system, suggesting widespread disruption over localized effects.

CONCLUSIONS

Contrary to previous beliefs, our findings challenge the idea that CD-related heading discrimination issues mainly arise from peripheral vestibular effects. Instead, abnormal proprioceptive input from dystonic neck muscles introduces noise into the central mechanism integrating visual, vestibular, and proprioceptive signals. These insights into spatial navigation deficits have implications for future CD research. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Utility of Neurophysiological Evaluation in Movement Disorders Clinical Practice

Background

Quantitative and objective neurophysiological assessment can help to define the predominant phenomenology and provide diagnoses that have prognostic and therapeutic implications for movement disorders.

Objectives

Evaluate the agreement between initial indications and final diagnoses after neurophysiological evaluations in a specialized movement disorders center.

Methods

Electrophysiological studies conducted for movement disorders from 2003 to 2021 were reviewed. The indications were classified according to predominant phenomenology and the diagnoses categorized in subgroups of phenomenology.

Results

A total of 509 studies were analyzed. 51% (259) of patients were female, with a mean age of 51 years (ranges 5 to 89 years). The most common reasons for referral were evaluation of functional movement disorders (FMD), followed by jerky movements, tremor and postural instability. Regarding FMD referrals, there was a diagnostic change in 13% of the patients after electrophysiological assessment. The patients with jerky movements as indication had a diagnosis other than myoclonus in 27% of them, and tremor was not confirmed in 20% of the cases. In patients with an electrophysiological diagnosis of FMD, it was not suspected in 30% of the referrals. Similarly, tremor was not mentioned in the referral of 17% of the patients with this electrophysiological diagnosis and myoclonus was not suspected in 13% of the cases.

Conclusions

Electrophysiological assessment has utility in the evaluation of movement disorders, even in patients evaluated by movement disorders neurologists. More studies are needed to standardize the protocols between centers and to promote the availability and use of these techniques among movement disorders clinics.

Assessing the efficacy of perilymphatic fistula repair surgery in alleviating vestibular symptoms and associated auditory impairments

Perilymph Fistula (PLF), abnormal communication between the fluid-filled space of the inner ear and the air-filled space of the middle ear, is a significant cause of vestibular and auditory symptoms. This is a retrospective study of 22 cases treated with PLF repair surgery, selected based on our surgical indication. We analyzed the characteristics of these 22 cases and evaluated the efficacy of PLF repair surgery in treating vestibular and auditory symptoms. Cases with antecedent events had significantly shorter intervals before surgery. The postoperative recovery from vestibular symptoms following PLF repair surgery was strikingly rapid, with 82% of cases demonstrating marked improvement within a week, even in chronic cases. Despite the notable absence of a control group in the study, the marked improvements in vestibular symptoms and substantial reductions in Dizziness Handicap Inventory (DHI) scores suggest that the observed benefits are attributable to the surgical intervention. Further, timely surgery showed improvements in hearing, with some benefits also seen in late-stage surgeries. Using the perilymph-specific protein Cochlin-tomoprotein (CTP) as a diagnostic biomarker, we could prove that PLF could be responsible for disequilibrium and related auditory disturbances in these patients. A new hypothesis is proposed that the chronic disequilibrium experienced by many PLF patients is due to enhanced mobility of the utricle and not to endolymphatic hydrops. Further research is needed to fully elucidate PLF's symptoms and treatment efficacy using the surgical indication we developed.

Behind the Mask of Parkinsonism: A Case Report and Literature Review on Progressive Supranuclear Palsy

Progressive supranuclear palsy (PSP) is a neurodegenerative condition that typically emerges in adulthood and does not exhibit any familial inheritance pattern. PSP is characterized by gradual stiffness in the central body, an inability to move the gaze upward voluntarily, postural instability, and a decline in cognitive function linked to frontal lobe dysfunction. Clinical assessment reveals a variety of findings, and cases of PSP frequently go unnoticed or are incorrectly diagnosed as other conditions. Notably, prominent neurotransmitter-related changes in PSP involve damage to the dopaminergic nigrostriatal pathway and cholinergic impairment in multiple regions. We hereby present a case of a 71-year-old female patient whose medical journey unfolds as a perplexing riddle. Despite the collective expertise of several physicians, she found herself bearing the weight of a misdiagnosis ascribed to Parkinson's Disease (PD) erroneously. She initially presented with recurring falls due to postural instability and bradykinesia, which progressed such that she became dependent on a walking aid. A comprehensive physical examination revealed indicators consistent with PSP.

Postural Instability and Risk of Falls in Patients with Parkinson's Disease Treated with Deep Brain Stimulation: A Stabilometric Platform Study

Postural instability (PI) in Parkinson's disease (PD) exposes patients to an increased risk of falls (RF). While dopaminergic therapy and deep brain stimulation (DBS) improve motor performance in advanced PD patients, their effects on PI and RF remain elusive. PI and RF were assessed using a stabilometric platform in six advanced PD patients. Patients were evaluated in OFF and ON dopaminergic medication and under four DBS settings: with DBS off, DBS bilateral, and unilateral DBS of the more- or less-affected side. Our findings indicate that dopaminergic medication by itself exacerbated PI and RF, and DBS alone led to a decline in RF. No combination of medication and DBS yielded a superior improvement in postural control compared to the baseline combination of OFF medication and the DBS-off condition. Yet, for ON medication, DBS significantly improved both PI and RF. Among DBS conditions, DBS bilateral provided the most favorable outcomes, improving PI and RF in the ON medication state and presenting the smallest setbacks in the OFF state. Conversely, the more-affected side DBS was less beneficial. These preliminary results could inform therapeutic strategies for advanced PD patients experiencing postural disorders.

Identifying Postural Instability in Children with Cerebral Palsy Using a Predictive Model: A Longitudinal Multicenter Study

Insufficient postural control and trunk instability are serious concerns in children with cerebral palsy (CP). We implemented a predictive model to identify factors associated with postural impairments such as spastic or hypotonic truncal tone (TT) in children with CP. We conducted a longitudinal, double-blinded, multicenter, descriptive study of 102 teenagers with CP with cognitive impairment and severe motor disorders with and without truncal tone impairments treated in two specialized hospitals (60 inpatients and 42 outpatients; 60 males, mean age 16.5 ± 1.2 years, range 12 to 18 yrs). Clinical and functional data were collected between 2006 and 2021. TT-PredictMed, a multiple logistic regression prediction model, was developed to identify factors associated with hypotonic or spastic TT following the guidelines of "Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis". Predictors of hypotonic TT were hip dysplasia (p = 0.01), type of etiology (postnatal > perinatal > prenatal causes; p = 0.05), male gender, and poor manual (p = 0.01) and gross motor function (p = 0.05). Predictors of spastic TT were neuromuscular scoliosis (p = 0.03), type of etiology (prenatal > perinatal > postnatal causes; p < 0.001), spasticity (quadri/triplegia > diplegia > hemiplegia; p = 0.05), presence of dystonia (p = 0.001), and epilepsy (refractory > controlled, p = 0.009). The predictive model's average accuracy, sensitivity, and specificity reached 82%. The model's accuracy aligns with recent studies on applying machine learning models in the clinical field.

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.

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.

Real world validation of activity recognition algorithm and development of novel behavioral biomarkers of falls in aged control and movement disorder patients

The use of wearable sensors in movement disorder patients such as Parkinson's disease (PD) and normal pressure hydrocephalus (NPH) is becoming more widespread, but most studies are limited to characterizing general aspects of mobility using smartphones. There is a need to accurately identify specific activities at home in order to properly evaluate gait and balance at home, where most falls occur. We developed an activity recognition algorithm to classify multiple daily living activities including high fall risk activities such as sit to stand transfers, turns and near-falls using data from 5 inertial sensors placed on the chest, upper-legs and lower-legs of the subjects. The algorithm is then verified with ground truth by collecting video footage of our patients wearing the sensors at home. Our activity recognition algorithm showed >95% sensitivity in detection of activities. Extracted features from our home monitoring system showed significantly better correlation (~69%) with prospectively measured fall frequency of our subjects compared to the standard clinical tests (~30%) or other quantitative gait metrics used in past studies when attempting to predict future falls over 1 year of prospective follow-up. Although detecting near-falls at home is difficult, our proposed model suggests that near-fall frequency is the most predictive criterion in fall detection through correlation analysis and fitting regression models.

Case report: Saccadic ping-pong gaze in progressive supranuclear palsy with predominant postural instability

We report a 63-year-old female patient with progressive supranuclear palsy (PSP). She presented predominant postural instability and "saccadic ping-pong gaze" (SPPG). She had unprovoked falls recurrently within a year from the onset of gait disturbance. She tended to fall backward with eye closure but had no freezing of gait on examination. She showed no signs of nuchal dystonia, limb tremor, rigidity, spasticity, or ataxia. The dopaminergic response was negative. On the initial examination, her vertical eye movements were normal, but frequent macro square wave jerks and SPPG were observed. SPPG consisted of short-cycle, horizontal conjugate irregular pendular oscillations of the eye position from the midpoint with superimposed small saccades. SPPG was observed usually in the dark, not in the daylight, and with eye closure by using electrooculogram and infrared charge-coupled device imaging. One and a half years after the first examination, she was diagnosed as probable PSP with vertical supranuclear gaze palsy. SPPG was first described in patients who are unconscious by Johkura in 1998 as a "saccadic" variant of "ping-pong gaze (PPG)." PPG, short-cycle periodic alternating gaze, has been described in comatose patients since 1967. On the other hand, abnormal eye movement, which looks the same as SPPG in coma, has been described in conscious patients with PSP or spinocerebellar degeneration (SCD) in Japanese literature since 1975. However, it has been called "transient alternating saccades (TAS)." Nowadays, we believe it is more appropriate to call this abnormal eye movement "SPPG" instead of TAS. Here, we propose that PSP, a neuro-degenerative disease, should be added as one of the etiologies of SPPG. We discuss the differences between PPG/SPPG in coma and SPPG in PSP and the possible pathophysiological mechanism of SPPG in relation to cerebellar oculomotor dysfunctions.

[Postural stability and walking in Parkinson's disease]

The article is of an overview nature and is devoted to movement disorders in Parkinson's disease. The article discusses the existing problems according to the latest literature data, a review on the treatment and rehabilitation of postural instability. Special attention in the article is paid to dopamine receptor agonists - namely, piribedil, prescribed for the correction of these disorders.

The 'Pants-Sign': A Predictor for Falling in People with Parkinson's Disease?

BACKGROUND

A history of falls is the most established predictor of future falls in people with Parkinson's disease (PD). However, predicting a first fall remains challenging.

OBJECTIVE

To assess whether experiencing difficulties putting on pants while standing is a viable predictor of future falling, and specifically a first fall, in persons with PD. We define this 'Pants-sign' as people who resort to putting on their pants only while seated.

METHODS

264 persons with PD were included. Information on the Pants-sign, history of falls, disease severity (MDS-UPDRS part III), freezing of gait (N-FOGQ > 0), cognitive function (MoCA), self-reported disability (Schwab & England scale), health-related quality of life (SF-12), Timed-Up-and-Go, and one-legged stance were determined at baseline and after one-year follow-up. The association between the Pants-sign and future falling was examined by univariate logistic regression analysis. A multivariate step-wise logistic regression with forward selection was employed to identify the strongest associations in the entire cohort and a sub-cohort of people without falls in the year prior to baseline.

RESULTS

The Pants-sign was univariably associated with a future fall (OR = 2.406, 95% CI [1.313-4.409], p = 0.004]), but was not an independent predictor in the multivariate logistic regression; predictors were higher MDS-UPDRS part III scores (OR = 1.088, 95% CI [1.056-1.121], p < 0.001] and history of falls (OR = 5.696, 95% CI [2.650-12.243], p≤0.001]. For the sub-cohort of people without falls in the previous year (n = 189), the Pants-sign was not associated with future falls.

CONCLUSIONS

The Pants-sign is simple to assess and is associated with future falling in PD but is not an independent predictor.

Machine Learning and Wearable Sensors for the Early Detection of Balance Disorders in Parkinson's Disease

Dynamic posturography combined with wearable sensors has high sensitivity in recognizing subclinical balance abnormalities in patients with Parkinson's disease (PD). However, this approach is burdened by a high analytical load for motion analysis, potentially limiting a routine application in clinical practice. In this study, we used machine learning to distinguish PD patients from controls, as well as patients under and not under dopaminergic therapy (i.e., ON and OFF states), based on kinematic measures recorded during dynamic posturography through portable sensors. We compared 52 different classifiers derived from Decision Tree, K-Nearest Neighbor, Support Vector Machine and Artificial Neural Network with different kernel functions to automatically analyze reactive postural responses to yaw perturbations recorded through IMUs in 20 PD patients and 15 healthy subjects. To identify the most efficient machine learning algorithm, we applied three threshold-based selection criteria (i.e., accuracy, recall and precision) and one evaluation criterion (i.e., goodness index). Twenty-one out of 52 classifiers passed the three selection criteria based on a threshold of 80%. Among these, only nine classifiers were considered "optimum" in distinguishing PD patients from healthy subjects according to a goodness index ≤ 0.25. The Fine K-Nearest Neighbor was the best-performing algorithm in the automatic classification of PD patients and healthy subjects, irrespective of therapeutic condition. By contrast, none of the classifiers passed the three threshold-based selection criteria in the comparison of patients in ON and OFF states. Overall, machine learning is a suitable solution for the early identification of balance disorders in PD through the automatic analysis of kinematic data from dynamic posturography.

Digitizing a Therapeutic: Development of an Augmented Reality Dual-Task Training Platform for Parkinson's Disease

Augmented reality (AR) may be a useful tool for the delivery of dual-task training. This manuscript details the development of the Dual-task Augmented Reality Treatment (DART) platform for individuals with Parkinson's disease (PD) and reports initial feasibility, usability, and efficacy of the DART platform in provoking dual-task interference in individuals with PD. The DART platform utilizes the head-mounted Microsoft HoloLens2 AR device to deliver concurrent motor and cognitive tasks. Biomechanical metrics of gait and cognitive responses are automatically computed and provided to the supervising clinician. To assess feasibility, individuals with PD (N = 48) completed a bout of single-task and dual-task walking using the DART platform. Usability was assessed by the System Usability Scale (SUS). Dual-task interference was assessed by comparing single-task walking and walking during an obstacle course while performing a cognitive task. Average gait velocity decreased from 1.06 to 0.82 m/s from single- to dual-task conditions. Mean SUS scores were 81.3 (11.3), which placed the DART in the "good" to "excellent" category. To our knowledge, the DART platform is the first to use a head-mounted AR system to deliver a dual-task paradigm and simultaneously provide biomechanical data that characterize cognitive and motor performance. Individuals with PD were able to successfully use the DART platform with satisfaction, and dual-task interference was provoked. The DART platform should be investigated as a platform to treat dual-task declines associated with PD.

Evaluation of the Functional Status of the Posture Control System in Children with Detected Disorders in Body Posture

Screening tests for body posture defects and abnormalities conducted over the past several decades have revealed a significant and constantly increasing problem of health risks in children. A sedentary lifestyle, which is considered to be the primary cause, can result in proprioceptive disorders leading to postural instability. The aim of the study was to find the correlation between the level of proprioceptive control and the number of postural disorders. The study involved a representative group of 1090 children aged 8-10 years, from randomly selected primary schools. Subjects who scored from 1 to 5 points in a prior postural screening test were qualified for the examination of the postural control system. The examination of the postural control system was carried out using an electronic station enabling assessment of postural stability and proprioception. A single leg stance test showed that the number of postural disorders does not significantly impact proprioceptive control. Proprioceptive control was found to significantly increase with the age of the children, and girls presented significantly better proprioceptive control in relation to the boys in each age group.

Exercise to Improve Postural Stability in Older Adults with Alzheimer's Disease: A Systematic Review of Randomized Control Trials

In this systematic review, we aim to synthesize published evidence on the effects of exercise in improving postural stability among older adults with Alzheimer's Disease (AD). A systematic electronic literature search was undertaken in Pedro, Cochrane, MEDLINE, ProQuest, Science direct and Clinical trial databases involving human participants published from year 2000-2022. This search was updated in June 2022. The studies chosen were based on predetermined criteria. Data relating to the contents and parameters of exercise in persons with AD were gathered and analyzed. A total of 8 experimental studies met the inclusion criteria. Overall, the selected studies were of a medium quality. In these studies, information and physical exercises were used to improve postural stability in older adults with AD. The findings of the review suggest that performing combined strength, balance and executive function training can improve postural stability. However, we are unable to conclude the specific dose for specific type of exercise. More high-quality studies are required pertaining to exercise prescription for older adults with AD. Mostly, information and physical exercise were delivered via face-to-face sessions conducted by health professionals. The structure of exercises summarized in this review may be beneficial for older adults with AD to improve postural stability and as a result reduce falls.

Neuroprotective Effects of Cranberry Juice Treatment in a Rat Model of Parkinson's Disease

Rich in polyphenols, cranberry juice (CJ) with high antioxidant activity is believed to contribute to various health benefits. However, our knowledge of the neuroprotective potential of cranberries is limited. Previously, we have demonstrated that CJ treatment controls oxidative stress in several organs, with the most evident effect in the brain. In this study, we examined the capability of CJ for protection against Parkinson's disease (PD) in a rotenone (ROT) rat model. Wistar rats were administered with CJ in a dose of 500 mg/kg b.w./day (i.g.) and subcutaneously injected with ROT (1.3 mg/kg b.w./day). The experiment lasted 45 days, including 10 days pre-treatment with CJ and 35 days combined treatment with CJ and ROT. We quantified the expression of α-synuclein and apoptosis markers in the midbrain, performed microscopic examination, and assessed postural instability to evaluate the CJ neuroprotective effect. Our results indicate that the juice treatment provided neuroprotection, as evidenced by declined α-synuclein accumulation, Bax and cleaved/active caspase-9 expression, and normalized cytochrome c level that was accompanied by the enhancement of neuronal activity survival and improved postural instability. Importantly, we also found that long-term administration of CJ alone in a relatively high dose may exert a deleterious effect on cell survival in the midbrain.

Pseudo-pheochromocytoma due to obstructive sleep apnea: a case report

SUMMARY

Obstructive sleep apnea (OSA) is a condition of intermittent nocturnal upper airway obstruction. OSA increases sympathetic drive which may result in clinical and biochemical features suggestive of pheochromocytoma. We present the case of a 65-year-old male with a 2.9-cm left adrenal incidentaloma on CT, hypertension, symptoms of headache, anxiety and diaphoresis, and persistently elevated 24-h urine norepinephrine (initially 818 nmol/day (89-470)) and normetanephrine (initially 11.2 µmol/day (0.6-2.7)). He was started on prazosin and underwent left adrenalectomy. Pathology revealed an adrenal corticoadenoma with no evidence of pheochromocytoma. Over the next 2 years, urine norepinephrine and normetanephrine remained significantly elevated with no MIBG avid disease. Years later, he was diagnosed with severe OSA and treated with continuous positive airway pressure. Urine testing done once OSA was well controlled revealed complete normalization of urine norepinephrine and normetanephrine with substantial symptom improvement. It was concluded that the patient never had a pheochromocytoma but rather an adrenal adenoma with biochemistry and symptoms suggestive of pheochromocytoma due to untreated severe OSA. Pseudo-pheochromocytoma is a rare presentation of OSA and should be considered on the differential of elevated urine catecholamines and metanephrines in the right clinical setting.

LEARNING POINTS

Obstructive sleep apnea (OSA) is a common condition among adults. OSA may rarely present as pseudo-pheochromocytoma with symptoms of pallor, palpitations, perspiration, headache, or anxiety. OSA should be considered on the differential of elevated urine catecholamines and metanephrines, especially in patients with negative metaiodobenzylguanidine (MIBG) scan results.

Parkinson's Disease Motor Subtypes Change with the Progression of the Disease: Results from the COPPADIS Cohort at 2-Year Follow-Up

BACKGROUND

Motor phenotype (MP) can be associated with a different prognosis in Parkinson's disease (PD), but it is not fixed and can change over time.

OBJECTIVE

Our aim was to analyze how the MP changed over time and to identify factors associated with the changes in PD patients from a multicenter Spanish PD cohort.

METHODS

PD patients who were recruited from January-2016 to November-2017 (baseline visit; V0) and evaluated again at a 2-year±30 days follow-up (V2) from 35 centers of Spain from the COPPADIS cohort, were included in this study.MP was calculated at both visits based on Jankovic classification in TD (tremor dominant), IND (indeterminate), or PIGD (postural instability and gait difficulty). Sociodemographic and clinical data were collected, including serum biomarkers.

RESULTS

Five hundred eleven patients (62.57±8.59 years old; 59.2%males) were included in the study. At V0, MP was: 47.4%(242/511) TD; 36.6%(187/511) PIGD; 16%(82/511) IND. Up to 38%(194/511) of the patients changed their phenotype from V0 to V2, being the most frequent from TD to IND (8.4%) and from TD to PIGD (6.7%). A worse cognitive status (OR = 0.966) and less autonomy for activities of daily living (OR  =  0.937) at V0 and a greater increase in the globalNMS burden (OR  =  1.011) from V0 to V2 were associated with changing from TD to another phenotype after 2-year follow-up.

CONCLUSION

The MP in PD can change over time. With disease progression, the percentage of cases with non-tremoric MP increases. PD patients who changed from TD to postural instability and gait difficulty increased NMS burden significantly.

Dynamic Visual Stimulations Produced in a Controlled Virtual Reality Environment Reveals Long-Lasting Postural Deficits in Children With Mild Traumatic Brain Injury

Motor control deficits outlasting self-reported symptoms are often reported following mild traumatic brain injury (mTBI). The exact duration and nature of these deficits remains unknown. The current study aimed to compare postural responses to static or dynamic virtual visual inputs and during standard clinical tests of balance in 38 children between 9 and 18 years-of-age, at 2 weeks, 3 and 12 months post-concussion. Body sway amplitude (BSA) and postural instability (vRMS) were measured in a 3D virtual reality (VR) tunnel (i.e., optic flow) moving in the antero-posterior direction in different conditions. Measures derived from standard clinical balance evaluations (BOT-2, Timed tasks) and post-concussion symptoms (PCSS-R) were also assessed. Results were compared to those of 38 healthy non-injured children following a similar testing schedule and matched according to age, gender, and premorbid level of physical activity. Results highlighted greater postural response with BSA and vRMS measures at 3 months post-mTBI, but not at 12 months when compared to controls, whereas no differences were observed in post-concussion symptoms between mTBI and controls at 3 and 12 months. These deficits were specifically identified using measures of postural response in reaction to 3D dynamic visual inputs in the VR paradigm, while items from the BOT-2 and the 3 timed tasks did not reveal deficits at any of the test sessions. PCSS-R scores correlated between sessions and with the most challenging condition of the BOT-2 and as well as with the timed tasks, but not with BSA and vRMS. Scores obtained in the most challenging conditions of clinical balance tests also correlated weakly with BSA and vRMS measures in the dynamic conditions. These preliminary findings suggest that using 3D dynamic visual inputs such as optic flow in a controlled VR environment could help detect subtle postural impairments and inspire the development of clinical tools to guide rehabilitation and return to play recommendations.

Motor and Non-motor Symptoms Associated With Exercise Behavior in Parkinson's Disease Patients: Factors Differ Between Patients With and Without Postural Instability

Background: Exercise is an important treatment for Parkinson's disease (PD). Therefore, recognizing determinants of exercise behavior for PD based on disease stage is essential. We sought to find whether the determinants differ based on presence of postural instability (PI), which is indicative of disease stage in PD. Methods: We enrolled patients at Samsung Medical Center from September 2019 to November 2020, who had the ability to perform exercise [modified Hoehn and Yahr (HY) stage ≤ 3]. All the motor and non-motor symptoms were investigated. The exercise of the PD patients was evaluated using the Physical Activity Scale of the Elderly (PASE)-leisure score. We classified patients into PD without PI (HY stage 1 - 2) and PD with PI (HY stage 2.5 - 3) groups. Multivariate linear regression was performed using backward elimination in each group to determine factors associated with PASE-leisure score. Results: A total of 233 patients were enrolled. In the PD without PI group (n = 177), the positive determinant of exercise was Activities-Specific Balance Confidence (ABC) score (β = 0.142, p = 0.032), and the negative determinants were fatigue score (β = -0.228, p = 0.018), female (β = -6.900, p = 0.016) and currently employed status (β = -6.072, p = 0.046). In the PD with PI group (n = 56), the positive determinant was non-motor symptom scale (NMSS) score (β = 0.221, p = 0.017) and disease duration (β = 1.001, p = 0.036), while the negative determinants were UPDRS part 3 score (β = -0.974, p < 0.001), UPDRS part 4 score (β = -2.192, p = 0.002), and age (β = -1.052, p < 0.001). Conclusion: Different motor and non-motor symptoms were associated with the exercise in PD patients with and without PI. When encouraging PD patients to exercise, personalized and different strategies should be applied based on the presence of PI.

Pedunculopontine and Cuneiform Nuclei Deep Brain Stimulation for Severe Gait and Balance Disorders in Parkinson's Disease: Interim Results from a Randomised Double-Blind Clinical Trial

BACKGROUND

Dopa-resistant freezing of gait (FOG) and falls represent the dominant motor disabilities in advanced Parkinson's disease (PD).

OBJECTIVE

We investigate the effects of deep brain stimulation (DBS) of the mesencephalic locomotor region (MLR), comprised of the pedunculopontine (PPN) and cuneiform (CuN) nuclei, for treating gait and balance disorders, in a randomized double-blind cross-over trial.

METHODS

Six PD patients with dopa-resistant FOG and/or falls were operated for MLR-DBS. Patients received three DBS conditions, PPN, CuN, or sham, in a randomized order for 2-months each, followed by an open-label phase. The primary outcome was the change in anteroposterior anticipatory-postural-adjustments (APAs) during gait initiation on a force platformResults:The anteroposterior APAs were not significantly different between the DBS conditions (median displacement [1st-3rd quartile] of 3.07 [3.12-4.62] cm with sham-DBS, 1.95 [2.29-3.85] cm with PPN-DBS and 2.78 [1.66-4.04] cm with CuN-DBS; p = 0.25). Step length and velocity were significantly higher with CuN-DBS vs. both sham-DBS and PPN-DBS. Conversely, step length and velocity were lower with PPN-DBS vs. sham-DBS, with greater double stance and gait initiation durations. One year after surgery, step length was significantly lower with PPN-DBS vs. inclusion. We did not find any significant change in clinical scales between DBS conditions or one year after surgery.

CONCLUSION

Two months of PPN-DBS or CuN-DBS does not effectively improve clinically dopa-resistant gait and balance disorders in PD patients.

The Impact of Parkinson's Disease on Postural Control in Older People and How Sex can Mediate These Results: A Systematic Review

INTRODUCTION

Parkinson's disease is most prevalent among elderly people, 65 years and over, and leads to an alteration in motor control associated with postural instability. Current evidence shows that postural control decreases with the aging process. In addition, postural control is more altered in healthy aged men than in women. Until today, few studies have evaluated the combined impact of Parkinson's disease and sex on postural control. This review has allowed to evaluate the impact of Parkinson's disease and sex on postural control measurements in elderly people.

METHODOLOGY

Studies have been selected from two main databases: PubMed and EBSCO using the keywords "Parkinson", "postural control OR balance" and "sex". Articles related to the evaluation of postural control, including men and women with Parkinson's aged over 65 years old, regardless of stage, were included (n = 179). Articles were excluded if not written in French or English or not presenting original content.

RESULTS

Ten (10) studies out of 179 that fulfilled inclusion and exclusion criteria were reported in the final analysis, which cumulates a total of 944 individuals with Parkinson's (410 women). In general, results show greater postural instability among people with Parkinson's compared to healthy subjects, and this according to different objective measurements using stabilographic parameters from force platforms. Only two studies out of ten evaluated postural control while briefly considering distinctions between sex, but without showing a significant difference between men and women with Parkinson's. Parkinson's severity, length of time of Parkinson's disease and cognitive state of the person are the three variables with a negative impact on postural control.

CONCLUSION

Older people with Parkinson's disease have greater postural instability. Sex does not seem to influence the postural control of elderly people with Parkinson's, although more studies are necessary.

Short- and Long-Term Effects of DBS on Gait in Parkinson's Disease

The aim was to compare the short and long-term effects of subthalamic nucleus (STN) deep brain stimulation (DBS) on gait dysfunction and other cardinal symptoms of Parkinson's disease (PD). Two groups of patients were studied. The first group (short-term DBS, n = 8) included patients recently implanted with STN DBS (mean time since DBS 15.8 months, mean age 58.8 years, PD duration 13 years); the second group (long-term DBS, n = 10) included patients with at least 5 years of DBS therapy (mean time since DBS 67.6 months, mean age 61.7 years, PD duration 17.1 years). Both groups were examined using the Unified Parkinson's Disease Rating Scale (UPDRS) and Gait and Balance scale (GABS) during four stimulation/medication states (ON/OFF; OFF/OFF; OFF/ON; ON/ON). Data were analyzed using repeated measures ANOVA with time since implantation (years) between groups and medication or DBS effect (ON, OFF) within groups. In the short-term DBS group, stimulation improved all UPDRS subscores similar to dopaminergic medications. In particular, average gait improvement was over 40% (p = 0.01), as measured by the UPDRS item 29 and GABS II. In the long-term DBS group, stimulation consistently improved all clinical subscores with the exception of gait and postural instability. In these patients, the effect of levodopa on gait was partially preserved. Short-term improvement of gait abnormalities appears to significantly decline after 5 years of STN DBS in PD patients, while effectiveness for other symptoms remains stable. Progressive non-dopaminergic (non-DBS responsive) mechanisms or deleterious effects of high frequency STN stimulation on gait function may play a role.

Axial Impairment Following Deep Brain Stimulation in Parkinson's Disease: A Surgicogenomic Approach

Background:

Postoperative outcome following deep brain stimulation (DBS) of the subthalamic nucleus is variable, particularly with respect to axial motor improvement. We hypothesized a genetic underpinning to the response to surgical intervention, termed “surgicogenomics”.

Objective:

We aimed to identify genetic variants associated with clinical heterogeneity in DBS outcome of Parkinson’s disease (PD) patients that could then be applied clinically to target selection leading to improved surgical outcome.

Methods:

Retrospective clinical data was extracted from 150 patient’s charts. Each individual was genotyped using the genome-wide NeuroX array tailored to study neurologic diseases. Genetic data were clustered based on surgical outcome assessed by comparing pre- and post-operative scores of levodopa equivalent daily dose and axial impairment at one and five years post-surgery. Allele frequencies were compared between patients with excellent vs. moderate/poor outcomes grouped using a priori defined cut-offs. We analyzed common variants, burden of rare coding variants, and PD polygenic risk score.

Results:

NeuroX identified 2,917 polymorphic markers at 113 genes mapped to known PD loci. The gene-burden analyses of 202 rare nonsynonymous variants suggested a nominal association of axial impairment with 14 genes (most consistent with CRHR1, IP6K2, and PRSS3). The strongest association with surgical outcome was detected between a reduction in levodopa equivalent daily dose and common variations tagging two linkage disequilibrium blocks with SH3GL2.

Conclusion:

Once validated in independent populations, our findings may be implemented to improve patient selection for DBS in PD.

Falls in individuals with type 2 diabetes; a cross-sectional study on the impact of motor dysfunction, postural instability and diabetic polyneuropathy

AIM

To estimate the incidence of falls in individuals with type 2 diabetes compared to healthy controls and to describe the characteristics of fallers with type 2 diabetes in relation to motor dysfunction, postural instability and diabetic polyneuropathy (DPN).

METHODS

This is a cross-sectional study of individuals with type 2 diabetes with DPN (n = 54), without DPN (n = 38) and healthy controls (n = 39). Falls were recorded within the preceding year. DPN was defined by clinical scores and nerve conduction studies. Motor function was assessed by a 6-min walk test (6 MWT), five-time sit-to-stand test (FTSST) and isokinetic dynamometry at the non-dominant ankle and knee. An instability index (ST) was measured using static posturography. Univariate and bivariate descriptive statistics were used for group comparisons.

RESULTS

Compared with healthy controls, individuals with diabetes had a higher incidence of falls 36%, (n = 33) versus 15%, (n = 6), p = 0.02. There were no differences in falls when comparing individuals with and without DPN. Fallers had an impaired 6 MWT versus non-fallers (450 ± 153 m vs. 523 ± 97 m respectively), a slower FTSST (11.9 ± 4.2 s vs. 10.3 ± 2.9 s respectively) and a higher ST (53 ± 29 vs. 41 ± 17 respectively), p < 0.02 for all.

CONCLUSION

Individuals with type 2 diabetes reported a higher number of falls within the preceding year compared to healthy controls, irrespective of the presence of DPN. The main factors associated with falls were increased postural instability, lower walking capacity and slower sit-to-stand movements. The 6 MWT, FTSST and posturography should be considered in future screening programs in identification of individuals at risk for falls.

Cerebral Hemodynamic Responses to the Difficulty Level of Ambulatory Tasks in Patients With Parkinson's Disease: A Systematic Review and Meta-Analysis

Background. Ambulatory tasks are the important components of balance training which effectively improve postural stability and functional activities in persons with Parkinson's disease (PD). The difficulty level of an ambulatory task is usually set in the form of attention, direction, speed, or amplitude requirement. Objectives. This study aimed to explore the neural mechanisms of cerebral hemodynamic responses to the difficulty level of ambulatory tasks in persons with PD. Methods. We included ten studies that examined cerebral hemodynamic responses during ambulatory tasks at different difficulty levels in persons with PD. The change in hemodynamic responses was synthesized and meta-analyzed. Results. Patients during "ON" medication had higher relative change in oxygenated hemoglobin (ΔHBO₂) in the prefrontal cortex in response to difficulty levels of ambulatory tasks, which is comparable to that in healthy elderly individuals. However, patients during "OFF" medication did not show cortical activation in response to difficulty levels. During the lower-difficulty tasks, patients during "ON" medication demonstrated higher ΔHBO₂ than healthy elderly participants and patients during "OFF" medication. Factors found to significantly contribute to the heterogeneity across studies included subjects' type and cognitive status, task duration, setting, and filter used for functional near-infrared spectroscopy (fNIRS) data pre-processing. Conclusions. The findings suggest that ambulatory task at a higher difficulty level could be necessary to train the cortical capacity of PD persons, which should be conducted during "ON" medication; meanwhile, the contributing factors to the heterogeneity of studies would be useful as a reference when designing comparable fNIRS studies.

Golf as a Physical Activity to Potentially Reduce the Risk of Falls in Older Adults with Parkinson's Disease

Advanced age is associated with an increased risk for falls in aging adults. Older adults are also more likely to be diagnosed with Parkinson’s disease (PD), with advanced age as the most significant risk factor. PD is a neurodegenerative disorder with four Cardinal motor symptoms: rigidity, bradykinesia, postural instability, and tremor. Thus, people (person)-with-Parkinson’s disease (PwP) have an even greater risk of falling than non-disorder age-matched peers. Exercise is an activity requiring physical effort, typically carried out to sustain or improve overall health and fitness, and it lowers the risk of falls in the general population. The sport of golf provides a low-impact all-around workout promoting a range of motion, activation of muscles in the upper and lower body, flexibility, and balance. Swinging a golf club offers a unique combination of high amplitude axial rotation, strengthening postural musculature, coordination, and stabilization, demonstrating the potential to impact PD symptoms positively. Golf may be a novel exercise treatment regimen for PD to use in conjunction with traditional medical therapy. We completed a literature review to determine the relationship between the game of golf, PD, and the risk of falls. We concluded that regularly playing golf can lower the risk for falls in community ambulating older adults with PD and demonstrates the potential to improve quality of life for PwP.

Effectiveness of robotic balance training on postural instability in patients with mild Parkinson's disease: A pilot, single blind, randomized controlled trial

OBJECTIVE

To examine whether tailored robotic platform training could improve postural stability compared with conventional balance treatment in patients with mild Parkinson's disease.  Design: Randomized single-blind pilot study.

SUBJECTS

Twenty-two patients with mild Parkinson's disease (Hoehn and Yahr scale; HandY 1-2).

METHODS

Patients were randomly assigned to an experimental group for robotic balance training and to a control group for conventional balance training. Each patient received 20 treatments (45 min/session, 5 times/week). Blinded evaluations were conducted before and after the treatment and 1 month post-treatment. Primary outcome measures were Mini BESTest, and Berg Balance Scale; secondary outcome measures were 10-Meter Walk Test, Five Times Sit to Stand Test, and Parkinson's Disease Questionnaire 39.

RESULTS

Primary outcome measures in patients in both the experimental and control groups improved significantly after the balance treatment. Similar results were found for all the secondary outcome measures. The experimental group performed significantly better than the control group at both post-intervention and follow-up evaluation in the primary outcomes (p < 0.05). No significant differences be-tween groups were found in secondary outcomes.

CONCLUSION

Robot-assisted balance training may be a promising tool to improve postural stability in patients with mild Parkinson's disease.

Proprioception: the missing link in the pathogenesis of tinnitus?

OBJECTIVES

The object of this study was to relate cervical spine pathology to the occurrence of tinnitus and of cervical pain.

DESIGN

A retrospective analysis of 124 patients with tinnitus as main complaint and 300 patients with cervical pain as main complaint who visited our clinic in a two-year period.

RESULTS

In patients with tinnitus as main complaint, 64% of the patients have also cervical pain, and in patients with cervical pain as main complaint, 44% of the patients have tinnitus. Both groups of patients have in common a high prevalence of postural instability and dizziness, degeneration of the intervertebral disc between the fifth and seventh cervical vertebrae, and a large anterior spur in front of the fifth cervical vertebrae. Patients with cervical pain as main complaint have more degeneration of the intervertebral disc between the third and fourth cervical vertebrae, a larger anterior spur in front of the third cervical vertebrae and more loss of cervical lordosis.

CONCLUSIONS

Postural instability is an important discriminant factor in patients with cervical pain and in patients with tinnitus as main complaint. In patients with cervical pain postural instability was associated with the occurrence of tinnitus. In patients with tinnitus, there is evidence for two profiles of somatic tinnitus, discriminated by the occurrence of postural instability and low-frequency hearing loss. It seems that the combination of tinnitus and postural instability begins as a cervical pain syndrome and that the tinnitus aggravates in time, possibly by the occurrence of hearing loss, internal diseases, or surgery of the lower limb.

The Relationship of Rapid Eye Movement Sleep Behavior Disorder and Freezing of Gait in Parkinson's Disease

Rapid eye movement sleep behavior disorder (RBD) contributes to injury due to the alteration of the expected atonia during rapid eye movement (REM) sleep. It occurs before the overt signs of Parkinson's disease (PD). The co-expression of PD and RBD is characterized by non-tremor predominant subtype and higher incidence of freezing. Freezing of gait (FOG) is a debilitating symptom seen in PD patients that lead to falls. While this phenomenon is understood poorly, the involvement of the pedunculopontine nucleus (PPN) and the neural circuits that control locomotion and gait have been examined. This network has also the same control for REM sleep and arousal. The close relationship between PD and RBD and FOG's consequences has led us to explore the relationship between RBD and PD with FOG. This review provides an overview of the neural connections that control gait, locomotion, and REM sleep. The neural changes were seen in PD with FOG and RBD, and sensory and motor changes observed in these two diseases. The functional neuroanatomy that controls REM sleep, arousal, and locomotion overlap significantly with multiple neural circuits affected in RBD and PD with FOG. Visual perception dysfunction and motor symptoms that primarily affect gait initiation are common to both patients with RBD and FOG in PD, leading to freezing episodes. Prospective studies should be conducted to elucidate the relationship of RBD and PD with FOG subtype and find innovative treatment approaches and diagnostic tools for PD with FOG.

Yoga Improves Balance and Low-Back Pain, but Not Anxiety, in People with Parkinson's Disease

Individuals with Parkinson's disease (PD) experience postural instability, low-back pain (LBP), and anxiety. These symptoms increase the risk of falls and decrease quality of life. Research shows yoga improves balance and decreases LBP and anxiety in healthy adults, but its effects in PD are poorly understood. All participants were part of a larger intervention study. Participants received pretest and posttest evaluations, including the Balance Evaluation Systems Test (BESTest), Beck Anxiety Inventory (BAI), and Revised Oswestry Disability Index (ROSW). Total scores for each measure, as well as individual balance system section scores from the BESTest (biomechanical constraints, stability limits/verticality, transitions/anticipatory, reactive, sensory orientation, and stability in gait) were compared within groups pre- to posttest. Participants in the yoga group (n = 13) completed a twice-weekly 12-week yoga interve n t i o n , whereas controls (n = 13) continued their usual routines for 12 weeks. Both the yoga (Z = -3.20, p = 0.001) and control (Z = -2.10, p = 0.040) groups improved on the BESTest total score. The control group showed no changes in individual balance systems, whereas the yoga group improved in stability limits/verticality (Z = -2.3, p = 0.020), transitions/ anticipatory (Z = -2.50, p = 0.010), reactive (Z = -2.70, p = 0.008), and sensory orientation (Z = -2.30, p = 0.020). ROSW decreased in the yoga group only (Z = -2.10, p = 0.030). BAI did not change in either group. Yoga is a nonpharmacological intervention that can improve balance and LBP in people with PD. This study demonstrated that yoga is feasible for people with PD, and participants reported high levels of enjoyment and intent to practice yoga after the study.

Clinical and laboratory measures of balance and comparison of balance performances according to postural instability and gait disorders in individuals with Parkinson's disease

PURPOSE/AIM

Primary aim was to investigate the association between laboratory measures of balance and clinical balance tests in individuals with Parkinson's disease (PD). The secondary aim was to compare the balance performances according to postural instability and gait disorders (PIGD).

MATERIALS AND METHODS

Sixty-four individuals with PD were included in the study. Clinical data were investigated using modified Hoehn and Yahr Scale and Unified Parkinson's Disease Rating Scale (UPDRS). Berg Balance Scale (BBS), Timed Up&Go Test (TUG), Five Times Sit-to-Stand Test (FTSST) were used for clinical measures of balance. Laboratory measures of balance were evaluated by Balance Master System including the modified Clinical Test of Sensory Interaction of Balance (mCTSIB), Limits of Stability Test (LOS), Sit to Stand Test (STS), and Tandem Walk Test (TW). The relationship between clinical and laboratory measures of balance was determined. After participants were divided into two groups based on UPDRS: patients with and without PIGD, their balance performance was compared.

RESULTS

There were significant correlations between BBS and mCTSIB, LOS-Movement Velocity, and LOS-Endpoint Excursion. FTSST was correlated with STS-Weight Transfer and STS-Rising Index, and TUG was correlated with TW-Speed. Patients with PIGD had worse scores of balance assessments including FTSST, LOS-Movement Velocity, STS-Rising Index.

CONCLUSION

Laboratory measures are associated with clinical balance tests and they may reflect clinical balance outcome measures. Furthermore, PIGD may negatively affect balance performance in patients with PD.

Instrumental Assessment of Stepping in Place Captures Clinically Relevant Motor Symptoms of Parkinson's Disease

Fluctuations of motor symptoms make clinical assessment in Parkinson's disease a complex task. New technologies aim to quantify motor symptoms, and their remote application holds potential for a closer monitoring of treatment effects. The focus of this study was to explore the potential of a stepping in place task using RGB-Depth (RGBD) camera technology to assess motor symptoms of people with Parkinson's disease. In total, 25 persons performed a 40 s stepping in place task in front of a single RGBD camera (Kinect for Xbox One) in up to two different therapeutic states. Eight kinematic parameters were derived from knee movements to describe features of hypokinesia, asymmetry, and arrhythmicity of stepping. To explore their potential clinical utility, these parameters were analyzed for their Spearman's Rho rank correlation to clinical ratings, and for intraindividual changes between treatment conditions using standard response mean and paired t-test. Test performance not only differed between ON and OFF treatment conditions, but showed moderate correlations to clinical ratings, specifically ratings of postural instability (pull test). Furthermore, the test elicited freezing in some subjects. Results suggest that this single standardized motor task is a promising candidate to assess an array of relevant motor symptoms of Parkinson's disease. The simple technical test setup would allow future use by patients themselves.

Psychosocial research in the diabetic foot: Are we making progress?

BACKGROUND/METHODS

This review summarizes recent advances regarding the role of psychological factors in people with a diabetic foot ulcer (DFU). It describes the detrimental effects of diabeticfoot complications and in particular, Charcot Neuroarthropathy (CN), on health status and quality of life (QoL) and emphasizes the importance of utilizing DFU-specific assessment tools.

RESULTS

Diabetic neuropathy (DN)-related postural instability is key in generating depression in high DFU risk patients and in predicting offloading non-adherence those with active DFUs. Patients' views of their own DFU risk are largely inconsistent with biomedical models, resulting in a lack of preventive foot self-care. Furthermore, DFUs are a source of specific emotional responses, with fear of amputation predominant. While fear of amputation is associated with better preventive foot self-care, it appears to be linked to DFU non-healing, though mechanisms are yet to be elucidated. Until now, systemically released stress hormones were recognized as the only biological mechanism through which psychological stress influences healing. Recently, the skin has been found to be an extra-adrenal site for glucocorticoid synthesis with local, tissue-specific cortisol implicated in DFU non-healing.

CONCLUSIONS

These observations could potentially lead to future targets for therapeutic and psychological interventions.

[Deep brain stimulation effect on postural instability and gait disorders in Parkinson's disease]

An effect of deep brain stimulation on postural instability and gait disorders in Parkinson's disease S.G. Sultanova, N.V. Fedorova, E.V. Bril, A.A. Gamaleya, A.A. Tomskiy During the last time, surgical treatment of patients with Parkinson's disease has firmly taken its place in the general algorithm for managing patients with this pathology. Deep brain electrostimulation is the most advanced and promising method, which allows the reduction in the severity of main clinical manifestations of the disease, including axial symptoms. It is noted that certain temporal aspects of parkinsonian gait disorder remain therapeutically resistant. Subthalamic nucleus stimulation was also reported to improve levodopa-responsive freezing of gait. In this review, the authors summarize the effects of deep brain stimulation on gait and postural symptoms.

A Novel MRI Compatible Balance Simulator to Detect Postural Instability in Parkinson's Disease

Background: Postural instability is a debilitating and largely treatment-resistant symptom of Parkinson's disease (PD). A better understanding of the neural substrates contributing to postural instability could lead to new targets for improved pharmacological and neurosurgical interventions. However, investigating these neural substrates necessitates the use of functional MRI scanners, which are almost exclusively horizontally-based. Objective: We aimed to develop, and validate the use of, an MRI compatible balance simulator to study static and dynamic balance control in PD patients and elderly controls. Methods: Our MRI compatible balance simulator allowed participants to actively balance an inverted pendulum by activating postural muscles around the ankle joint while supine. Two studies were performed to compare static and dynamic balance performance between upright stance and simulated stance in PD patients and controls. Study 1 (14 PD; 20 controls) required participants to maintain static balance during upright and simulated stance for 120 s with eyes open and closed. In study 2 (20 PD; 22 controls) participants repeated the static balance task (80 s, eyes closed only), and also completed a dynamic balance task which required maintaining balance while experiencing random anterior-posterior perturbations applied to the trunk/pendulum. Postural sway of the body/pendulum was measured using an angular velocity sensor (SwayStar^TM, study 1) and Optotrak motion capture (study 2). Outcome measures were amplitude and frequency of center of mass sway for static balance, and peak and time-to-peak of center of mass displacement and velocity for dynamic balance. Results: PD patients had larger sway amplitude during both upright and simulated static balance compared to controls. PD patients had larger peak and time-to-peak sway, and larger time-to-peak sway velocity, during simulated, but not upright, dynamic balance compared to controls. Conclusions: Deficits in static and dynamic balance control can be detected in PD patients using a novel MRI compatible balance simulator. This technique allows for functional neuroimaging to be combined with balance-relevant tasks, and provides a new means to create insights into the neural substrates contributing to postural instability in PD.

Postural instability according to virtual reality program

Background: The popularity of virtual reality (VR) grew rapidly. Short guidelines with a lack of emphasis on safe use appears prior to usage. It is necessary for the user to realize how much potentially dangerous VR is. Aims/objectives: The aim of this study is to investigate the effect of VR on balance in normal people. Materials and methods: Mean equilibrium score (MES) of 15 adults who have normal sense of balance were obtained by using the sensory organization test (SOT). Conditions 1 and 2 were performed. Multiple VR programs were classified as three levels (Easy, Average, and Challenging) by the visual analog scale. Further SOT tests were performed during watching VR programs. MES of each test was used for statistical analysis. Results: MES of condition 1 was significantly higher than condition 2. Although there was no statistical difference between Eye open and Easy program (p = .097), MES of average and Challenging programs showed significantly decreased scores compared to Eye open. In addition, MES of Average and Challenging programs were significantly decreased than that of Easy program. Conclusions and significance: VR can cause postural imbalance to users. It is necessary to establish quantifiable and objective methods to measure imbalance caused by VR use.

Usefulness Differs Between the Visual Assessment and Specific Binding Ratio of 123I-Ioflupane SPECT in Assessing Clinical Symptoms of Drug-Naïve Parkinson's Disease Patients

Background: In clinical practice, assessment of the striatal accumulation in ¹²³I-ioflupane single photon emission computed tomography (SPECT) is commonly performed calculating the specific binding ratio (SBR) for the whole striatum. On the other hand, visual assessment of striatal accumulation in the SPECT was recently established. However, correlations of visual assessment with motor and cognitive functions in Parkinson’s disease (PD) have rarely been examined. Differences in the usefulness of these assessments at clinics are uncertain.

Objective: We performed this study to compare correlations of cognitive and motor functions in drug-naive PD between the SBR and visual assessment using ¹²³I-ioflupane SPECT.

Methods: Cognitive and motor assessments and ¹²³I-ioflupane SPECT were performed in 47 drug-naïve PD patients with Mini-mental State Examination scores of ≥25. Cognitive function was assessed using the total score and 6 subscores of the Montreal Cognitive Assessment (MoCA) and 10 separate subtests of the Neurobehavioral Cognitive Status Examination (COGNISTAT). Motor function was assessed using the Hoehn and Yahr scale and Unified Parkinson’s Disease Rating Scale. Accumulation of ¹²³I-ioflupane was determined by visual assessment based on five grades: 1, burst striatum; 2, egg-shaped; 3, mixed type; 4, eagle wing; 5, normal striatum; and by calculating SBR averaged for the bilateral striatum using the DaTView computer software commonly used in clinical practice. Each SPECT assessment was compared with each subscore for cognitive and motor assessments.

Results: Spearman correlation analysis showed SBR was significantly correlated with the MoCA subscores of visuospatial function and attention, and with COGNISTAT subtests of attention. Visual assessment showed significant negative correlation with the Hoehn and Yahr scale. Mean score of postural instability in patients with visual grade of 1 was significantly higher than those in patients with visual grades of 2 and 3.

Conclusion: Clinical symptoms reflected by ¹²³I-ioflupane SPECT differ between the SBR and visual assessment. SBR reflects some cognitive functions, whereas a visual assessment grade of 1, which signifies decreased uptake of ¹²³I-Ioflupane in the caudate nucleus, reflects postural instability. Thus, the caudate nucleus may play an important role in posture maintenance. Our results suggest that performing both assessments is of value.

7.0T ultrahigh-field MRI directly visualized the pedunculopontine nucleus in Parkinson's disease patients

OBJECTIVES

The pedunculopontine nucleus (PPN) is considered a promising new target for neurostimulation in Parkinson's disease (PD) patients with postural instability and gait disturbance that is refractory to other treatment modalities. However, the PPN is typically difficult to visualize with magnetic resonance imaging (MRI) at clinical field strengths, which greatly limits the PPN as a viable surgical target for deep brain stimulation (DBS). Thus, the aim of this study is to directly visualize the PPN based on 7.0T ultrahigh-field MRI.

METHODS

Five PD patients were enrolled and scanned using the MP2RAGE sequence on a 7.0T ultrahigh-field MRI scanner. Then, the MP2RAGE sequences were imported into a commercially available navigation system. The coordinates of the directly localized PPN poles were recorded in the navigation system relative to the anterior commissure-posterior commissure plane.

RESULTS

Our results indicated that the PPN presented intermediate signal intensity in the 7.0T ultrahigh-field MR images in comparison with the surrounding structure, such as the hypo-intensity of the periaqueductal gray and the hyperintensity of the neighboring white matter tracts, in PD patients. The mean coordinates for the rostral and caudal poles of PPN were 6.50 mm and 7.20 mm lateral, 1.58 mm and 2.21 mm posterior, and 8.89 mm and 13.83 mm relative to the posterior commissure.

CONCLUSION

Our findings provide, for the first time, direct visualization of the PPN using the MP2RAGE sequence on a 7.0T ultrahigh-field MRI, which may improve the accuracy of stereotactic targeting of the PPN and improve the outcomes in patients undergoing DBS.

Balance and mobility in patients with newly diagnosed Parkinson's disease - a five-year follow-up of a cohort in northern Sweden

Background: The presence of early balance impairment in patients with Parkinson's disease has not been fully investigated.Purpose: The purpose of this study was to examine balance and mobility, self-perceived unsteadiness, self-reported falls, and effects of medication on balance among patients at their first visit to a neurological clinic and during the ensuing five years.Materials and methods: The participants were collected from a prospective longitudinal study. One hundred and forty-five patients with idiopathic Parkinson's disease and 31 healthy controls were included. The outcome measures were the Berg Balance Scale, the Timed Up and Go, the Postural Stability test and a questionnaire.Results: At their first visit to the neurological clinic, the patients performed less well on the Berg Balance Scale (p < 0.001, r = 0.36), the Timed Up and Go (p < 0.001, r = 0.32), and the Postural Stability test (p < 0.001, r = 0.35) compared with the controls. In addition, a higher percentage of the patients reported self-perceived unsteadiness (p < 0.001, phi = 0.47). During the ensuing five years, balance and mobility worsened both with and without medication (p < 0.01, r = 0.24-0.37), although with small median differences.Conclusions: Further studies are needed to confirm that minor balance impairments exist even at the time of diagnosis and worsen during the ensuing five years.IMPLICATIONS FOR REHABILITATIONImpairments in balance and mobility may occur early in Parkinson's disease, especially in the elderly patients, and seem to worsen during the first five years.There is a need to use sensitive outcome measures and to ask the patients about unsteadiness and falls to detect balance impairment in this cohort.Parkinsonian medication has a limited effect on balance and may preferably be complemented with balance exercises to target balance impairment early in Parkinson's disease.

A posturographic procedure assessing balance disorders in Parkinson's disease: a systematic review

Postural instability is common in Parkinson's disease (PD), often contributing to falls, injuries, and reduced mobility. In the clinical setting, balance disorder is commonly diagnosed using clinical tests and balance scales, but it is suggested that the most sensitive measurement is the force platform. The aim of this systematic review was to summarize the methods and various posturographic procedures used to assess the body balance and gait in PD. A systematic review was conducted of papers published from 2000 to 2017. Databases searched were PubMed and EBSCO. Studies must have involved patients with PD, used force platform or motion analysis system as a measurement tool, and described posturographic procedure. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality of the included studies. A total of 32 studies met the inclusion criteria. The PEDro scores ranged from 5 to 7 points. The analysis of the objective methods assessing balance disorders revealed a large discrepancy in the duration and procedures of measurements. The number of repetitions of each trial fluctuated between 1 and 8, and the duration of a single trial ranged from 10 to 60 seconds. Overall, there are many scales and tests used to assess the balance disorders and disabilities of people with PD. Although in many included studies the authors have used posturography as a method to evaluate the postural instability of PD patients, the results are contradictory. To solve this issue, it is indicated to establish a "gold standard" of procedures of measures of balance.