Movement Disorders最新文献

Parkinson's disease is a complex neurodegenerative disorder characterized by degeneration of dopaminergic neurons, with patients manifesting varying motor and nonmotor symptoms. Previous studies using single-cell RNA sequencing in rodent models and humans have identified distinct heterogeneity of neurons and glial cells with differential vulnerability. Recent studies have increasingly leveraged multiomics approaches, including spatial transcriptomics, epigenomics, and proteomics, in the study of Parkinson's disease, providing new insights into pathogenic mechanisms. Continued advancements in experimental technologies and sophisticated computational tools will be essential in uncovering a network of neuronal vulnerability and prioritizing disease modifiers for novel therapeutics development. © 2025 International Parkinson and Movement Disorder Society.

Background: Wider step width and lower step-to-step variability are linked to improved gait stability and reduced fall risk. It is unclear if patients with spinocerebellar ataxia (SCA) can learn to adjust these aspects of gait to reduce fall risk.

Objectives: The aims were to examine the possibility of using wearable step width haptic biofeedback to enhance gait stability and reduce fall risk in individuals with SCA.

Methods: Thirteen people with SCA type 3 performed step width training (single session) using real-time feedback.

Results: Step width increased post-training (19.3 cm, interquartile range [IQR] 16.3-20.2 cm) and at retention (16.6 cm, IQR 16.2-21.1 cm), compared to baseline (11.0 cm, IQR 5.2-15.2 cm; P < 0.001). Step width variability decreased during post-training (19.7%, IQR 17.4%-26.2%) and at retention (22.3%, IQR 18.6%-30.2%), compared to baseline (44.5%, IQR 28.5%-71.2%; P < 0.001). Crossover steps, another mark of instability, decreased after training (P < 0.031).

Conclusions: These pilot results suggest that patients with SCA can use a novel, wearable biofeedback system to improve their gait stability. © 2025 International Parkinson and Movement Disorder Society.

Background: Essential tremor (ET) is a common type of tremor. Previous research has shown that wearable orthoses and biomechanical loading methods can suppress tremors.

Objective: This study aims to investigate the effect of a harmonic liquid dampener on upper extremity ET.

Methods: The study involved 9 women and 5 men from a neurology outpatient clinic. A 285-g liquid-based harmonic dampening wristband was used. Tremors were recorded from the wrist along the x-y-z axes using a vibrometer, and the Bain-Findley Rating Scale (BFRS) was employed for assessment.

Results: BFRS scores significantly improved after the wristband was used (mean difference 35.64, P = 0.001, Cohen's d effect size =2.979). The tremor amplitude decreased significantly along the x-axis (Cohen's d: 1.35, P = 0.001), y-axis (Cohen's d: 3.232, P = 0.001), and z-axis (Cohen's d: 3.321, P = 0.001).

Conclusion: The liquid-filled harmonic dampening wristband shows promise as a new, effective treatment option for ET patients. © 2025 International Parkinson and Movement Disorder Society.

Background: The recent Movement Disorders Society (MDS)-progressive supranuclear palsy (PSP) diagnostic criteria conceptualized three clinical diagnostic certainty levels: "suggestive of PSP" for sensitive early diagnosis based on subtle clinical signs, "possible PSP" balancing sensitivity and specificity, and "probable PSP" highly specific for PSP pathology.

Objective: The aim of this study was to prospectively validate the criteria against long-term clinical follow-up and characterize the diagnostic certainty increase over time.

Methods: Patients with "possible PSP" or "suggestive of PSP" diagnosis and clinical follow-up were recruited in two German multicenter longitudinal observational studies (ProPSP and DescribePSP). The cumulative percentage of patients longitudinally increasing diagnostic certainty was assessed over up to 2.5 years of follow-up. The sample size per arm required to detect 30% attenuated rate in diagnostic certainty increase in trials was estimated over multiple time intervals.

Results: Of 254 patients with available longitudinal data, 61 patients had low diagnostic certainty at baseline (48 suggestive of PSP, 13 possible PSP) and multiple clinical visits (median: 3, range: 2-4). The cumulative percentage of patients increasing diagnostic certainty progressed with follow-up duration (30.4% at 6 months, 51.7% at 1 year, 80.4% at 2.5 years). The sample size required to detect 30% reduction in diagnostic certainty increase rate within 1 year was 163, slightly smaller than that required using the PSP rating scale.

Conclusions: Most "suggestive of PSP" patients increased diagnostic certainty upon longitudinal follow-up, providing the first prospective multicenter validation of MDS-PSP diagnostic criteria. Our data support the design of trials tailored for these early-stage patients, suggesting the PSP rating scale and the diagnostic certainty increase rate as potential endpoint measures. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Background: Quantitative evidence of levodopa-induced beneficial effects on parkinsonian rigidity in Parkinson's disease (PD) is lacking. Recent research has demonstrated the velocity-dependent nature of objective rigidity in PD and revealed its neural underpinning.

Objective: The present study aimed to examine the effect of levodopa on objective rigidity in PD.

Methods: Eighteen patients with PD underwent clinical and instrumental evaluations of muscle tone in the OFF and ON states. The clinical assessments focused on rigidity in the most affected upper limb. The biomechanical components of objective rigidity were assessed using robot-assisted wrist extensions at seven angular velocities (5-280°/s). Surface electromyography of the flexor carpi radialis muscle enabled the concurrent evaluation of short- and long-latency stretch reflexes (SLR and LLR).

Results: Levodopa improved the clinical scores of rigidity. Biomechanical measurements showed that levodopa reduced the total and neural components of force but had no effect on viscoelastic components. Levodopa reduced the velocity dependence of the LLRs but did not affect the SLRs. Finally, we found significant clinical-instrumental correlations between levodopa-induced changes and biomechanical and neurophysiological measures of objective rigidity in PD.

Conclusions: Levodopa improved objective rigidity in PD by decreasing its biomechanical neural component as well as the size of LLRs. The beneficial effect of levodopa on biomechanical and neurophysiological features of objective rigidity was related to the specific angular velocity of wrist extensions; that is, the higher the angular velocity, the greater the beneficial impact of levodopa on objective rigidity. These findings allowed the description of a new pathophysiological model of rigidity in PD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.