Repeated Gait Perturbation Training in Parkinson's Disease and Healthy Older Adults: A Systematic Review and Meta-Analysis

Effects of protective step training on proactive and reactive motor adaptations in Parkinson's disease patients

The aim of this study was to investigate to what extent PD affects the ability to walk, respond to balance perturbations in a single training session, and produce acute short-term effects to improve compensatory reactions and control of unperturbed walking stability. Understanding the mechanism of compensation and neuroplasticity to unexpected step perturbation training during walking and static stance can inform treatment of PD by helping to design effective training regimens that remediate fall risk. Current rehabilitation therapies are inadequate at reducing falls in people with Parkinson's disease (PD). While pharmacologic and surgical treatments have proved largely ineffective in treating postural instability and gait dysfunction in people with PD, studies have demonstrated that therapy specifically focusing on posture, gait, and balance may significantly improve these factors and reduce falls. The primary goal of this study was to assess the effectiveness of a novel and promising intervention therapy (protective step training - i.e., PST) to improve balance and reduce falls in people with PD. A secondary goal was to understand the effects of PST on proactive and reactive feedback responses during stance and gait tasks. Multiple-baseline, repeated measures analyses were performed on the multitude of proactive and reactive performance measures to assess the effects of PST on gait and postural stability parameters. In general, the results indicate that participants with PD were able to use experiences with perturbation training to integrate and adapt feedforward and feedback behaviors to reduce falls. The ability of the participants with PD to adapt to changes in task demands suggests that individuals with PD could benefit from the protective step training to facilitate balance control during rehabilitation.

The effect of perturbation-based balance training on balance control and fear of falling in older adults: a single-blind randomised controlled trial

BACKGROUND

Perturbation-based balance training (PBT) is an emerging intervention shown to improve balance recovery responses and reduce falls in everyday life in older adults. However, perturbation interventions were heterogeneous in nature and need improvement. This study aims to investigate the effects of a PBT protocol that was designed to address previously identified challenges of PBT, in addition to usual care, on balance control and fear of falling in older adults at increased risk of falling.

METHODS

Community-dwelling older adults (age ≥ 65 years) who visited the hospital outpatient clinic due to a fall incident were included. Participants received PBT in addition to usual care (referral to a physiotherapist) versus usual care alone. PBT consisted of three 30-minute sessions in three weeks. Unilateral treadmill belt accelerations and decelerations and platform perturbations (shifts and tilts) were applied during standing and walking on the Computer Assisted Rehabilitation Environment (CAREN, Motek Medical BV). This dual-belt treadmill embedded in a motion platform with 6 degrees of freedom is surrounded by a 180° screen on which virtual reality environments are projected. Duration and contents of the training were standardised, while training progression was individualised. Fear of falling (FES-I) and balance control (Mini-BESTest) were assessed at baseline and one week post-intervention. Primary analysis compared changes in outcome measures between groups using Mann-Whitney U tests.

RESULTS

Eighty-two participants were included (PBT group n = 39), with a median age of 73 years (IQR 8 years). Median Mini-BESTest scores did not clinically relevantly improve and were not significantly different between groups post-intervention (p = 0.87). FES-I scores did not change in either group.

CONCLUSIONS

Participation in a PBT program including multiple perturbation types and directions did not lead to different effects than usual care on clinical measures of balance control or fear of falling in community-dwelling older adults with a recent history of falls. More research is needed to explore how to modulate PBT training dose, and which clinical outcomes are most suitable to measure training effects on balance control.

TRIAL REGISTRATION

Nederlands Trial Register NL7680. Registered 17-04-2019 - retrospectively registered. https://www.trialregister.nl/trial/7680 .

[New approaches in exercise therapy for Parkinson's disease]

BACKGROUND

Exercise therapy is an important component in the treatment of motor symptoms in people with Parkinson's disease (PD). In this context, goal-based task-specific training has shown to be particularly effective compared to nonspecific approaches.

OBJECTIVE

In this article two novel exercise interventions for targeted improvement of motor function in PD are presented: 1) task-specific training with perturbations and 2) combined task-specific and cardiovascular training.

MATERIAL AND METHODS

Summary and discussion of the current evidence for both therapeutic approaches.

RESULTS

First randomized controlled trials show that perturbation training is an effective task-specific training to improve gait and balance function and potentially reduce falls. Experimental findings on combined cardiovascular exercise and task-specific training suggest that processes of neuroplasticity are enhanced, thereby improving therapy outcomes. However, the quality of evidence for both therapeutic approaches is currently low.

CONCLUSION

The presented exercise approaches show promising results in first randomized controlled studies and have the potential to improve treatment outcomes in PD. Further high-quality clinical studies are needed to ensure an effective transfer into practice.

Perturbation-based balance training: Principles, mechanisms and implementation in clinical practice

Since the mid-2000s, perturbation-based balance training has been gaining interest as an efficient and effective way to prevent falls in older adults. It has been suggested that this task-specific training approach may present a paradigm shift in fall prevention. In this review, we discuss key concepts and common issues and questions regarding perturbation-based balance training. In doing so, we aim to provide a comprehensive synthesis of the current evidence on the mechanisms, feasibility and efficacy of perturbation-based balance training for researchers and practitioners. We address this in two sections: "Principles and Mechanisms" and "Implementation in Practice." In the first section, definitions, task-specificity, adaptation and retention mechanisms and the dose-response relationship are discussed. In the second section, issues related to safety, anxiety, evidence in clinical populations (e.g., Parkinson's disease, stroke), technology and training devices are discussed. Perturbation-based balance training is a promising approach to fall prevention. However, several fundamental and applied aspects of the approach need to be further investigated before it can be widely implemented in clinical practice.

The Effectiveness of Perturbation-Based Training in the Treatment of Patients With Stroke: A Systematic Review and Meta-Analysis

Purpose:

To investigate the effectiveness of perturbation-based training (PBT) on balance and balance confidence in patients with stroke.

Methods:

Systematic searching was performed from inception to November 2021. The inclusion criteria were RCTs assessed the effectiveness of PBT in patients with stroke. Data regarding participants, intervention parameters, outcome measures, follow-up, and main results were extracted. The outcomes were balance and balance confidence. Methodological quality and quality of evidence were assessed using the Physiotherapy Evidence Database (PEDro) scale and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system; respectively.

Data analysis:

A total of 7 articles )271 patients) were included. A meta-analysis using a random-effect model was performed on 6 studies. Standardized mean difference (SMD) with a 95% confidence interval was calculated for balance and balance confidence.

Results:

PEDro scale revealed 5 good-quality and 2 fair-quality studies. The currently available evidence showed significant effect of PBT in improving balance (SMD 0.60 [95% CI 0.15-1.06]; P = .01; very low-quality evidence) and non-significant in improving balance confidence (SMD 0.11 [95% CI −0.24 to 0.45]; P = .55; low-quality evidence).

Conclusion:

PBT may improve balance in patients with stroke, however its effect on balance confidence was limited. The quality of the evidence was low or very low with little confidence in the effect estimate, which suggests further high-quality trials are required.

Registration:

PROSPERO registration number (CRD42021291474).