Gait festination in parkinsonism: introduction of two phenotypes

Cough Correlates of Functional Swallow Outcomes in Atypical Parkinsonism

BACKGROUND

Swallow and cough impairments lead to aspiration and reduced clearance of aspirate material. Both behaviors are impaired in Parkinson's disease, but it is unknown whether a similar relationship of dysfunction exists in forms of atypical Parkinsonism (APD). Elucidating this association in APD may lead to early, comprehensive airway protection treatment.

OBJECTIVES

We tested the hypotheses that swallow deficits in APD are associated with impaired cough and that airway protective dysfunction is associated with longer disease duration.

METHODS

Swallowing difficulty was described by 11 participants with APD. Penetration-Aspiration Scale (PAS) and DIGEST scores for thin liquid trials were extracted from medical records of videofluoroscopic swallow study reports. Voluntary and capsaicin induced-reflex cough measures of flow, volume, and timing were analyzed.

RESULTS

While most participants did not have post-swallow residue, ~80% received abnormal PAS scores and reported swallowing difficulty. Those with abnormal PAS scores had lower voluntary cough expired volume (P = 0.037; mean rank difference = 5.0); lower reflex inspiratory flow rate (P = 0.034; mean rank difference = 5.5); and longer reflex expiratory flow rise time (P = 0.034; mean rank difference = 5.5). Higher PAS scores and reduced reflex cough volume acceleration were significantly correlated (r = -0.63; P = 0.04) and longer disease duration predicted larger voluntary cough expired volume (R2  = 0.72) and longer flow rise times (R2  = 0.47).

CONCLUSIONS

As swallow safety worsens, so might the ability to clear the airways with effective cough in in APD; particularly with longer disease duration. Assessing cough in conjunction with swallowing is important for informing airway protection treatment plans in APD.

Grid cells: the missing link in understanding Parkinson's disease?

The mechanisms underlying Parkinson's disease (PD) are complex and not fully understood, and the box-and-arrow model among other current models present significant challenges. This paper explores the potential role of the allocentric brain and especially its grid cells in several PD motor symptoms, including bradykinesia, kinesia paradoxa, freezing of gait, the bottleneck phenomenon, and their dependency on cueing. It is argued that central hubs, like the locus coeruleus and the pedunculopontine nucleus, often narrowly interpreted in the context of PD, play an equally important role in governing the allocentric brain as the basal ganglia. Consequently, the motor and secondary motor (e.g., spatially related) symptoms of PD linked with dopamine depletion may be more closely tied to erroneous computation by grid cells than to the basal ganglia alone. Because grid cells and their associated central hubs introduce both spatial and temporal information to the brain influencing velocity perception they may cause bradykinesia or hyperkinesia as well. In summary, PD motor symptoms may primarily be an allocentric disturbance resulting from virtual faulty computation by grid cells revealed by dopamine depletion in PD.

Residual effects of combined vibratory and plantar stimulation while seated influences plantar pressure and spatiotemporal gait measures in individuals with Parkinson's disease exhibiting freezing of gait

Introduction

Combined plantar pressure and vibratory stimulation has been shown to decrease freezing of gait (FOG) episodes and improve spatiotemporal gait parameters compared to single stimulation in Parkinson's disease (PD) patients with FOG. However, the effect of combined plantar stimulations on plantar pressure analysis has never been explored.

Methods

Forty PD patients with frequent FOG were allocated to either FOG shoes embedded with a 100 Hz vibratory stimulation at the Achilles tendons and a soft thickened silicone pad at the hallux and sole, or sham shoes with a non-working vibratory motor and a flat non-pressure silicone pad (20 patients per arm) while seated for 96 s. The objective gait and plantar pressure analysis were measured immediately after the stimulation. Outcomes included the normalized percentage of changes in percent FOG (%FOG) and plantar pressure in the heel-strike and push-off phase that were compared between pre- and post-stimulations.

Results

The FOG shoes group showed significantly decreased %FOG (81.5 ± 28.9% vs. 6.8 ± 22.1%, p < 0.001), plantar pressure in the heel-strike (47.8 ± 43.7% vs. 4.3 ± 9.8%, p < 0.001), plantar pressure in the push-off (57.7 ± 59.6% vs. 6.2 ± 11.6%, p < 0.001), force time integral (FTI) (40.9 ± 32.5% vs. 6.6 ± 17.3%, p < 0.001), and decreased heel contact time (19.3 ± 12.3% vs. 22.7 ± 32.5%, p < 0.001) when compared to the sham group. There was a strong negative correlation between %FOG and peak plantar pressure (r = -0.440, p = 0.005), plantar pressure in the heel-strike (r = -0.847, p < 0.001).

Conclusion

Our study demonstrated that the FOG shoe could decrease FOG episodes by improving the heel-strike pressure, toe push-off and normalized heel-to-toe plantar pressure, suggesting that modification inputs from the peripheral sensory systems might significant improvement in FOG in PD.

A Review of Artificial Intelligence-Based Gait Evaluation and Rehabilitation in Parkinson's Disease

Parkinson's disease (PD) is a long-term degenerative disease of the central nervous system that affects both motor and non-motor functions. In most cases, symptoms develop gradually, with non-motor symptoms increasing in frequency as the condition progresses. Tremors, stiffness, slow movements, and difficulty walking are some of the early symptoms. There may be problems with cognition, behavior, sleep, and thinking. Dementia caused by PD becomes more common as the disease progresses. The development of PD is linked to certain sequences of motion that eventually contribute to diminished function. Patients with Parkinson's disease (PWPD) have a sluggish, scattered gait that is accompanied by intermittent freezing of gait (FOG), in which efficient heading briefly pauses. In individuals with severe PD, FOG is a neurological deficit that is related to falls and has an unfavorable impact on the patient's standard of living. Artificial intelligence (AI) and ambient intelligence (AmI) are inextricably linked as intelligence is the ability to gain new information and employ it in novel contexts. The ambience is what accompanies us, while artificial represents something developed by humans. Wearable technologies are being designed to recognize FOG and support patients in the beginning to walk again via periodic cueing. The article proposes a unique automated approach for action description that utilizes AI to carry out a non-intrusive, markerless evaluation in real-time and with full robotics. This computerized method accelerates detection and safeguards from human error. Despite significant improvements brought about by the advent of novel technologies, the available assessment platforms still fail to strike the ideal equilibrium among expenditure, diagnostic precision, velocity, and simplicity. The value of the recommended approach can be seen through a comparison of the gait parameters collected by each of the motion-tracking gadgets.

Inpatient charges, complication, and revision rates for shoulder arthroplasty in Parkinson disease: a regional database study

BACKGROUND

Parkinson disease (PD) is an established risk factor for higher rates of complications and revision surgery following shoulder arthroplasty, yet the economic burden of PD remains to be elucidated. The purpose of this study is to compare rates of complication and revisions as well as inpatient charges for shoulder arthroplasty procedures between PD and non-PD patients using an all-payer statewide database.

METHODS

Patients undergoing primary shoulder arthroplasty from 2010 to 2020 were identified from the New York (NY) Statewide Planning and Research Cooperative System (SPARCS) database. Study groups were assigned based on concomitant diagnosis of PD at the time of index procedure. Baseline demographics, inpatient data, and medical comorbidities were collected. Primary outcomes measured were accommodation, ancillary, and total inpatient charges. Secondary outcomes included postoperative complication and reoperation rates. Logistic regression was performed to evaluate effect of PD on shoulder arthroplasty revision and complication rates. All statistical analysis was performed using R.

RESULTS

A total of 39,011 patients (429 PD vs. 38,582 non-PD) underwent 43,432 primary shoulder arthroplasties (477 PD vs. 42,955 non-PD) with mean follow-up duration of 2.9 ± 2.8 years. The PD cohort was older (72.3 ± 8.0 vs. 68.6 ± 10.4 years, P < .001), with greater male composition (50.8% vs. 43.0%, P = .001), and higher mean Elixhauser scores (1.0 ± 4.6 vs. 7.2 ± 4.3, P < .001). The PD cohort had significantly greater accommodation charges ($10,967 vs. $7,661, P < .001) and total inpatient charges ($62,000 vs. $56,000, P < .001). PD patients had significantly higher rates of revision surgery (7.7% vs. 4.2%, P = .002) and complications (14.1% vs. 10.5%, P = .040), as well as significantly higher incidences of readmission at 3 and 12 months postoperatively. After controlling for age and baseline comorbidities, PD patients had 1.64 times greater odds of reoperation compared to non-PD patients (95% CI 1.10, 2.37; P = .012) and a hazard ratio of 1.54 for reoperation when evaluating revision-free survival following primary shoulder arthroplasty (95% CI 1.07, 2.20; P = .019).

CONCLUSIONS

PD confers a longer length of stay, higher rates of postoperative complications and revisions, and greater inpatient charges in patients undergoing TSA. Knowledge of the associated risks and resource requirements of this population will aid surgeons in their decision making as they continue to provide care to a growing number of patients affected by PD.

Reliability and variability of physiotherapists scoring freezing of gait through video analysis

BACKGROUND

The "gold standard" marker for freezing of gait severity is percentage of time spent with freezing observed through video analysis.

OBJECTIVE

This study examined inter- and intra-rater reliability and variability of physiotherapists rating freezing of gait severity through video analysis and explored the effects of experience.

METHODS

Thirty physiotherapists rated 14 videos of Timed Up and Go performance by people with Parkinson's and gait freezing. Ten videos were unique, while four were repeated. Freezing frequency, total duration, and percentage of time spent with freezing were computed. Reliability and variability were estimated using ICC (2,1) and mean absolute differences. Between-group differences were calculated with the one-way ANOVA.

RESULTS

Inter- and intra-rater reliability ranged from moderate to good (ICC: inter-rater frequency = 0.63, duration = 0.78, percentage = 0.50; intra-rater frequency = 0.84, duration = 0.89, percentage = 0.50). Variability for freezing frequency was two episodes. Inter- and intra-rater variability for total freezing duration was 18.8 and 12.3  seconds, respectively. For percentage of time spent with freezing, this was 15.2% and 13.5%. Physiotherapy experience had no effect.

CONCLUSION

Physiotherapists demonstrated sufficient reliability, but variability was large enough to cause changes in severity classifications on existing rating scales. Percentage of time spent with freezing was the least reliable marker, supporting the use of freezing frequency or total duration instead.

Troubleshooting Gait Disturbances in Parkinson's Disease With Deep Brain Stimulation

Deep brain stimulation (DBS) of the subthalamic nucleus or the globus pallidus is an established treatment for Parkinson's disease (PD) that yields a marked and lasting improvement of motor symptoms. Yet, DBS benefit on gait disturbances in PD is still debated and can be a source of dissatisfaction and poor quality of life. Gait disturbances in PD encompass a variety of clinical manifestations and rely on different pathophysiological bases. While gait disturbances arising years after DBS surgery can be related to disease progression, early impairment of gait may be secondary to treatable causes and benefits from DBS reprogramming. In this review, we tackle the issue of gait disturbances in PD patients with DBS by discussing their neurophysiological basis, providing a detailed clinical characterization, and proposing a pragmatic programming approach to support their management.

Stepping up to meet the challenge of freezing of gait in Parkinson's disease

There has been a growing appreciation for freezing of gait as a disabling symptom that causes a significant burden in Parkinson’s disease. Previous research has highlighted some of the key components that underlie the phenomenon, but these reductionist approaches have yet to lead to a paradigm shift resulting in the development of novel treatment strategies. Addressing this issue will require greater integration of multi-modal data with complex computational modeling, but there are a number of critical aspects that need to be considered before embarking on such an approach. This paper highlights where the field needs to address current gaps and shortcomings including the standardization of definitions and measurement, phenomenology and pathophysiology, as well as considering what available data exist and how future studies should be constructed to achieve the greatest potential to better understand and treat this devastating symptom.

Using Motor Imagery to Access Alternative Attentional Strategies When Navigating Environmental Boundaries to Prevent Freezing of Gait – A Perspective

Freezing of gait can cause reduced independence and quality of life for many with Parkinson’s disease. Episodes frequently occur at points of transition such as navigating a doorway. Therapeutic interventions, i.e., drugs and exercise, do not always successfully mitigate episodes. There are several different, but not exclusive causes for freezing of gait. People with freezing of gait are able to navigate dynamic situations like stairways by utilizing a different attentional strategy to over-ground walking, but may freeze when passing through a doorway. The question is, is it possible to employ a special attentional strategy to prevent freezing at this point? Motor imagery allows for learning motor skills in absolute safety and has been widely employed in a variety of populations, including other neuro-compromised groups. Motor imagery is not studied in a homologous manner in people with Parkinson’s Disease, leading to conflicting results, but may have the potential to establish a different attentional strategy which allows a subject to mitigate freezing of gait episodes. This paper will identify and discuss the questions that still need to be answered in order to consider this approach i.e., can this population access motor imagery, can motor imagery alter the attentional strategy employed when moving through doorways, what is the best motor imagery approach for people with Parkinson’s Disease and freezing of gait, and what dosage is most effective, while briefly outlining future research considerations.

Impaired Weight-Shift Amplitude in People with Parkinson's Disease with Freezing of Gait

BACKGROUND

People with Parkinson's disease and freezing of gait (FOG; freezers) suffer from pronounced postural instability. However, the relationship between these phenomena remains unclear and has mostly been tested in paradigms requiring step generation.

OBJECTIVE

To determine if freezing-related dynamic balance deficits are present during a task without stepping and determine the influence of dopaminergic medication on dynamic balance control.

METHODS

Twenty-two freezers, 16 non-freezers, and 20 healthy age-matched controls performed mediolateral weight-shifts at increasing frequencies when following a visual target projected on a screen (MELBA task). The amplitude and phase shift differences between center of mass and target motion were measured. Balance scores (Mini-BESTest), 360° turning speed and the freezing ratio were also measured. Subjects with Parkinson's disease were tested ON and partial OFF (overnight withdrawal) dopaminergic medication.

RESULTS

Freezers had comparable turning speed and balance scores to non-freezers and took more levodopa. Freezers produced hypokinetic weight-shift amplitudes throughout the MELBA task compared to non-freezers (p = 0.002), which were already present at task onset (p < 0.001). Freezers also displayed an earlier weight-shift breakdown than controls when OFF-medication (p = 0.008). Medication improved mediolateral weight-shifting in freezers and non-freezers. Freezers decreased their freezing ratio in response to medication.

CONCLUSION

Hypokinetic weight-shifting proved a marked postural control deficit in freezers, while balance scores and turning speed were similar to non-freezers. Both weight-shift amplitudes and the freezing ratio were responsive to medication in freezers, suggesting axial motor vigor is levodopa-responsive. Future work needs to test whether weight-shifting and freezing severity can be further ameliorated through training.

Forward gait instability in patients with Parkinson's disease with freezing of gait

Freezing of gait (FOG) appears to be associated with increased risk of forward falls in patients with Parkinson's disease (PD). This study aimed to experimentally validate forward gait instability in PD patients with FOG (PD + FOG). Eleven PD + FOG patients, 9 PD patients without FOG (PD - FOG), and 13 healthy controls participated. Self-selected paced gait was analyzed by a three-dimensional motion-capture analysis system. We assessed the distance between the center of mass and the base of support (COM-BOS distance) and the margin of stability (MOS), considering the position and velocity of the COM as gait stability parameters, spatiotemporal gait parameters and kinematic parameters. The anteroposterior COM-BOS distance was smaller in PD + FOG patients than in PD-FOG patients and controls. Anteroposterior MOS was larger in PD + FOG and PD - FOG patients than controls (p < 0.05). PD + FOG patients showed smaller anteroposterior MOS than PD - FOG patients, when adjusting for disease severity (p < 0.05). Only in the PD + FOG group, when adjusting for disease severity, step length was positively correlated with the anteroposterior COM-BOS distance (p < 0.05), and cadence was negatively correlated with the anteroposterior MOS (p < 0.05). These results indicated that PD patients with FOG have forward gait instability and suggested that such instability may be associated with reduced step length and increased cadence.

Balance response to levodopa predicts balance improvement after bilateral subthalamic nucleus deep brain stimulation in Parkinson's disease

The effect of subthalamic nucleus deep brain stimulation (STN-DBS) on balance function in patients with Parkinson’s disease (PD) and the potential outcome predictive factors remains unclear. We retrospectively included 261 PD patients who underwent STN-DBS and finished the 1-month follow-up (M1) assessment in the explorative set for identifying postoperative balance change predictors, and 111 patients who finished both the M1 and 12-month follow-up (M12) assessment in the validation set for verifying the identified factors. Motor and balance improvement were evaluated through the UPDRS-III and the Berg balance scale (BBS) and pull test (PT), respectively. Candidate predictors of balance improvement included age, disease duration, motor subtypes, baseline severity of PD, cognitive status, motor and balance response to levodopa, and stimulation parameters. In the off-medication condition, STN-DBS significantly improved BBS and PT performance in both the M1 and M12, in both datasets. While in the on-medication condition, no significant balance improvement was observed. Higher preoperative BBS response to levodopa was significantly associated with larger postoperative off-medication, but not on-medication, BBS (p < 0.001) and PT (p < 0.001) improvement in both the M1 and M12. BBS subitems 8, 9, 11, 13, and 14 were the major contributors to the prediction of balance improvement after STN-DBS. STN-DBS improves short-term off-medication, but not on-medication, balance function assessed through BBS and PT. Preoperative BBS response to levodopa best predicts postoperative off-medication balance improvement. For patients who manifested severe balance problems, a levodopa challenge test on BBS or the short version of BBS is recommended.

The Transition from Standing to Walking Is Affected in People with Parkinson's Disease and Freezing of Gait

BACKGROUND

It has been hypothesized that freezing of gait (FOG) in people with Parkinson's disease (PD) is due to abnormal coupling between posture and gait.

OBJECTIVE

In this study, we examined the relationship between anticipatory postural adjustments (APAs) preceding gait initiation and the kinematics of the first two steps between people with FOG and without FOG.

METHODS

The kinetics and kinematics of self-initiated gait were recorded in 25 people with PD (11 with FOG, 14 without FOG). Outcome variables included the amplitude and timing of the ground reaction forces (GRFs), center of pressure (CoP) shifts and the spatial and temporal characteristics of the first and second steps.

RESULTS

The magnitude and timing of the APA phase of gait initiation were not significantly different between participants with and without FOG, yet the first step in the FOG group was distinguished by a significantly wider and less variable first step width, followed by a subsequent wider and shortened second step with reduced toe clearance. Multiple linear regression showed that the relationship between the initial conditions (stance width), APAs (posterior shift of the CoP) and the kinematics of the first step were different between groups with a significantly increased slope in the FOG group.

CONCLUSION

These findings demonstrate that the transition from standing to walking is different between those with and without FOG and that alterations in the initial conditions or APAs are more likely to impact the execution of the two steps in people with FOG.

The Minimal Clinically Relevant Change of the FOG Score

BACKGROUND

Freezing of gait is a highly disabling symptom in persons with Parkinson's disease (PwP). Despite its episodic character, freezing can be reliably evaluated using the FOG score. The description of the minimal clinically relevant change is a requirement for a meaningful interpretation of its results.

OBJECTIVE

To determine the minimal clinically relevant change of the FOG score.

METHODS

We evaluated video recordings of a standardized freezing-evoking gait parkour, i.e., the FOG score just before and 30 minutes after the intake of a regular levodopa dose in a randomized blinded fashion. The minimal clinically relevant response was considered a value of one or more on a 7-step Likert-type response scale [-3; +3] that served as the anchor. The minimal clinically relevant change was determined by ROC analysis.

RESULTS

37 PwP (Hoehn & Yahr stages 2.5-4, 27 male, 10 female) were aged 68.2 years on average (range 45-80). Mean disease duration was 12.9 years (2-29 years). Minimum FOG score was 0 and Maximum FOG score was 29. Mean FOG scores before medication were 10.6, and 11.1 after medication intake, with changes ranging from -14.7 to +16.7. The minimal clinically relevant change (MCRC) for improvement based on expert clinician rating was three scale points with a sensitivity of 0.67 and a specificity of 0.96.

CONCLUSIONS

The FOG score is recognized as a useful clinical instrument for the evaluation of freezing in the clinical setting. Knowledge of the MCRC should help to define responses to interventions that are discernible and meaningful to the expert physician and to the patient.

Muscular and cortical activation during dynamic and static balance in the elderly: A scoping review

Falls due to balance impairment are a major cause of injury and disability in the elderly. The study of neurophysiological correlates during static and dynamic balance tasks is an emerging area of research that could lead to novel rehabilitation strategies and reduce fall risk. This review aims to highlight key concepts and identify gaps in the current knowledge of balance control in the elderly that could be addressed by relying on surface electromyographic (EMG) and electroencephalographic (EEG) recordings. The neurophysiological hypotheses underlying balance studies in the elderly as well as the methodologies, findings, and limitations of prior work are herein addressed. The literature shows: 1) a wide heterogeneity in the experimental procedures, protocols, and analyses; 2) a paucity of studies involving the investigation of cortical activity; 3) aging-related alterations of cortical activation during balance tasks characterized by lower cortico-muscular coherence and increased allocation of attentional control to postural tasks in the elderly; and 4) EMG patterns characterized by delayed onset after perturbations, increased levels of activity, and greater levels of muscle co-activation in the elderly compared to younger adults. EMG and EEG recordings are valuable tools to monitor muscular and cortical activity during the performance of balance tasks. However, standardized protocols and analysis techniques should be agreed upon and shared by the scientific community to provide reliable and reproducible results. This will allow researchers to gain a comprehensive knowledge on the neurophysiological changes affecting static and dynamic balance in the elderly and will inform the design of rehabilitative and preventive interventions.

[The history of Freezing-of-gait in Parkinson's disease - from phenomena to symptom]

The background of the freezing-of-gait (FOG) phenomenon in Parkinson's syndrome is presented in this review. The following issues are addressed: characterization of the symptom freezing and its subtypes that challenge standardized diagnostic procedures; available assessment methods generating freezing-related parameters that not only support clinical studies but can also be applied in everyday care, and current therapy options. FOG exists in different subtypes, and clinical and diagnostic definitions are limited by subjective characterization and semi-standardized tests. FOG-specific drug options are not existing, apart from the optimization of dopaminergic medication, which may also be due to the poor discriminatory power of standardized diagnostics. This is also true for deep brain stimulation. Both of these therapeutic options may be due not only to the complex neural network alterations as a motor-control correlate of FOG, but also because of challenging diagnostic assessments methodologies. Innovative, wearable, sensor-based diagnostic strategies are currently being developed, and supportive therapies using tools and technologies focusing on 'cueing' are becoming increasingly well accepted. Even though high level evidence is missing, they provide a helpful treatment option for individualized therapy. It can be assumed that these options will become particularly popular due to technological progress and likely alter the everyday treatment challenges faced by doctors and therapists.

Effectiveness of Exercise on the Sequence Effect in Parkinson's Disease

Objective

To determine the benefits of motor training on the sequence effect (SE), an essential component of bradykinesia in Parkinson’s disease (PD).

Methods

Seven patients with de novo PD participated in this study. The patients performed regular pentagon drawing tests and exercises during four visits. The first two visits occurred before the start of medication, and the last two visits occurred at least six months after the start of medication. We assessed the severity of bradykinesia and SE at each visit and compared the results before and after exercise in both the de novo and treatment conditions.

Results

In the de novo condition, the severity of bradykinesia significantly improved after motor training (p = 0.018), but it did not resolve and only showed a trend of improvement after treatment (p = 0.068). The severity of the SE decreased significantly in the drug-naïve condition (p = 0.028) but not after medication (p = 0.273).

Conclusion

Our study suggests that regular motor training may be beneficial for the SE in PD.

A data-driven approach for detecting gait events during turning in people with Parkinson's disease and freezing of gait

BACKGROUND

Manual annotation of initial contact (IC) and end contact (EC) is a time consuming process. There are currently no robust techniques available to automate this process for Parkinson's disease (PD) patients with freezing of gait (FOG).

OBJECTIVE

To determine the validity of a data-driven approach for automated gait event detection.

METHODS

15 freezers were asked to complete several straight-line and 360 degree turning trials in a 3D gait laboratory during the off-period of their medication cycle. Trials that contained a freezing episode were indicated as freezing trials (FOG) and trials without a freezing episode were termed as functional gait (FG). Furthermore, the highly varied gait data between onset and termination of a FOG episode was excluded. A Temporal Convolutional Neural network (TCN) was trained end-to-end with lower extremity kinematics. A Bland-Altman analysis was performed to evaluate the agreement between the results of the proposed model and the manual annotations.

RESULTS

For FOG-trials, F1 scores of 0.995 and 0.992 were obtained for IC and EC, respectively. For FG-trials, F1 scores of 0.997 and 0.999 were obtained for IC and EC, respectively. The Bland-Altman plots indicated excellent timing agreement, with on average 39% and 47% of the model predictions occurring within 10 ms from the manual annotations for FOG-trials and FG-trials, respectively.

SIGNIFICANCE

These results indicate that our data-driven approach for detecting gait events in PD patients with FOG is sufficiently accurate and reliable for clinical applications.

Gait and postural disorders in parkinsonism: a clinical approach

Disturbances of balance, gait and posture are a hallmark of parkinsonian syndromes. Recognition of these axial features can provide important and often early clues to the nature of the underlying disorder, and, therefore, help to disentangle Parkinson’s disease from vascular parkinsonism and various forms of atypical parkinsonism, including multiple system atrophy, progressive supranuclear palsy, and corticobasal syndrome. Careful assessment of axial features is also essential for initiating appropriate treatment strategies and for documenting the outcome of such interventions. In this article, we provide an overview of balance, gait and postural impairment in parkinsonian disorders, focusing on differential diagnostic aspects.