The DizzyQuest Combined with Accelerometry: Daily Physical Activities and Limitations among Patients with Bilateral Vestibulopathy Due to DFNA9.

BACKGROUND: DFNA9 is a genetic disease of the inner ear, causing progressive bilateral sensorineural deafness and bilateral vestibulopathy (BV). In this study, DizzyQuest, a mobile vestibular diary, and the MOX accelerometer were combined to assess the daily life functional limitations and physical activity of patients with DFNA9 suffering from BV. These parameters might be appropriate as potential candidacy criteria and outcome measures for new therapeutic interventions for BV. METHODS: Fifteen DFNA9 patients with BV and twelve age-matched healthy controls were included. The DizzyQuest was applied for six consecutive days, which assessed the participants' extent of functional limitations, tiredness, types of activities performed during the day, and type of activity during which the participant felt most limited. The MOX accelerometer was worn during the same six days of DizzyQuest use, measuring the participants intensity and type of physical activity. Mixed-effects linear and logistic regression analyses were performed to compare the DFNA9 patients and control group. RESULTS: DFNA9 patients with BV felt significantly more limited in activities during the day compared to the age-matched controls, especially in social participation (p < 0.005). However, these reported limitations did not cause adjustment in the types of activities and did not reduce the intensity or type of physical activity measured with accelerometry. In addition, no relationships were found between self-reported functional limitations and physical activity. CONCLUSIONS: This study demonstrated that self-reported functional limitations are significantly higher among DFNA9 patients with BV. As a result, these limitations might be considered as part of the candidacy criteria or outcome measures for therapeutic interventions. In addition, the intensity or type of physical activity performed during the day need to be addressed more specifically in future research.

The ESA Parastronaut Feasibility Project: Investigating the Need and Contents of Physical Performance Tests for an Inclusive European Astronaut Corps.

INTRODUCTION: In 2022, the European Space Agency (ESA) held the first astronaut selection since the beginning of space flight that allowed physically impaired astronaut candidates to be selected in an inclusive European astronaut corp. The main objective of the 'parastronaut feasibility project' is to investigate if physical performance tests (PPTs) should be part of future astronaut recruitments for an inclusive ESA astronaut corps to test their flight readiness. The objectives of this study are (1) to assess if future (para-)astronaut recruitment campaigns should include PPTs to ensure flight readiness, safety, and mission success; (2) if so, which areas of physical performance should be tested to mimic nominal and off-nominal crew activities during all phases of a space mission; and (3) to assess whether PPTs are compatible with the ethical principles of equal opportunity for an inclusive pool of astronaut candidates. METHODS: 58 subject matter experts with specialisations in space physiology, operational human space flight, space medicine, medical ethics or parasports were interviewed in two rounds using the Delphi method. Both qualitative and quantitative data were obtained, analysed, categorised, and visualised using the qualitative research tool NVivo and Excel. RESULTS: Two thirds of the experts were in favour of adding PPTs to future astronaut selections and recommended to implement them for both physically unimpaired and physically impaired astronaut candidates. The main physical skills that should be examined are space-related, mission-specific coordination skills of the upper extremities, followed by endurance performance and stamina, dexterity of the upper extremities, motor learning ability and mobility. CONCLUSION: Based on this study, it is clear that PPTs should be part of future astronaut selection campaigns. However, the content of these PPTs must be carefully evaluated and validated using existing data on crew activities before, during, and after space flight, while considering equal opportunities in the context of human space flight. Historical considerations have influenced current astronaut requirements, but this study's findings indicate a need to reassess these requirements for future inclusive selection campaigns, as their validity and necessity remain uncertain.

Proportion of falls reported in persons with Parkinson's disease: A meta-analysis.

OBJECTIVE: Falls can be highly debilitating and have an important negative impact on the quality of life of patients with Parkinson's disease (PD). The aim of this systematic review and meta-analysis is to provide an up-to-date overview of the prevalence of ≥1 fall and ≥2 falls in idiopathic PD. DATA SOURCES: MEDLINE, Web of Science, Embase and Cinahl databases were systematically searched until 04 July 2022 for prospective studies reporting fall prevalence in persons with idiopathic PD. METHODS: Pooled prevalence rates with 95% confidence intervals (CIs) were computed using random-effects models. Heterogeneity among studies was assessed using the I2 statistic. RESULTS: A total of 54 studies (7546 participants) were included, and random-effects meta-analysis yielded a pooled proportional fall rate of 0.48 (95% CI [0.43-0.52], I2 = 93%, 46 studies, 6874 participants) for classification 1 (≥1 fall) and a pooled proportional fall rate of 0.32 (95% CI [0.27-0.37], I2 = 78%, 31 studies, 5672 participants) for classification 2 (≥2 falls). Subgroup analysis on the classification of falls, and length and method of monitoring falls did not reveal significant differences and did not reduce between-study variability. CONCLUSION: Pooled estimates suggest that one in two persons with PD fall at least once, and one in three fall at least twice within the registered time period. Substantial variability remains after pooling fall prevalence rates according to the length and method of monitoring. Therefore, no recommendations can be made concerning these methodological aspects. Future research on falls in PD is encouraged to implement best practice recommendations to monitor and report fall data.

Human movement in simulated hypogravity-Bridging the gap between space research and terrestrial rehabilitation.

Human movement is optimized to Earth's gravity and based on highly complex interactions between sensory and neuro-muscular systems. Yet, humans are able to adapt-at least partially-to extreme environments upon and beyond Earth's surface. With upcoming Lunar Gateway and Artemis missions, it is crucial to increase our understanding of the impact of hypogravity-i.e., reduced vertical loading-on physiological and sensory-motor performances to improve countermeasure programs, and define crewmember's readiness to perform mission critical tasks. Several methodologies designed to reduce vertical loading are used to simulate hypogravity on Earth, including body weight support (BWS) devices. Countering gravity and offloading the human body is also used in various rehabilitation scenarios to improve motor recovery in neurological and orthopedic impairments. Thus, BWS-devices have the potential of advancing theory and practice of both space exploration and terrestrial rehabilitation by improving our understanding of physiological and sensory-motor adaptations to reduced vertical loading and sensory input. However, lack of standardization of BWS-related research protocols and reporting hinders the exchange of key findings and new advancements in both areas. The aim of this introduction paper is to review the role of BWS in understanding human movement in simulated hypogravity and the use of BWS in terrestrial rehabilitation, and to identify relevant research areas contributing to the optimization of human spaceflight and terrestrial rehabilitation. One of the main aims of this research topic is to facilitate standardization of hypogravity-related research protocols and outcome reporting, aimed at optimizing knowledge transfer between space research and BWS-related rehabilitation sciences.

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

BACKGROUND: Balance impairment is a frequent cause of morbidity and mortality in people with Parkinson's disease (PD). As opposed to the effects of appendicular motor symptoms, the effects of Levodopa on balance impairment in idiopathic PD are less clear. OBJECTIVE: To review the literature on the effects of oral Levodopa on clinical balance test performance, posturography, step initiation, and responses to perturbation in people with idiopathic PD (PwPD). METHODS: A systematic search of three scientific databases (Pubmed, Embase, and Web of Science) was conducted in accordance with PRISMA guidelines. For the pilot meta-analysis, standardized mean differences with 95% confidence intervals were calculated using an inverse variance random effects model. Data not suitable for implementation in the meta-analysis (missing means or standard deviations, and non-independent outcomes) were analyzed narratively. RESULTS: A total of 2772 unique studies were retrieved, of which 18 met the eligibility criteria and were analyzed, including data of 710 idiopathic PwPD. Levodopa had a significant positive effect on the Berg Balance Scale, the Push and Release test, and jerk and frequency parameters during posturography. In contrast, some significant negative effects on velocity-based sway parameters were found during posturography and step initiation. However, Levodopa had no significant effect on most step initiation- and all perturbation parameters. CONCLUSION: The effects of Levodopa on balance in PwPD vary depending on the outcome parameters and patient inclusion criteria. A systematic approach with well-defined outcome parameters, and prespecified, sensitive and reliable tests is needed in future studies to unravel the effects of oral Levodopa on balance.

Movement in low gravity environments (MoLo) programme-The MoLo-L.O.O.P. study protocol.

BACKGROUND: Exposure to prolonged periods in microgravity is associated with deconditioning of the musculoskeletal system due to chronic changes in mechanical stimulation. Given astronauts will operate on the Lunar surface for extended periods of time, it is critical to quantify both external (e.g., ground reaction forces) and internal (e.g., joint reaction forces) loads of relevant movements performed during Lunar missions. Such knowledge is key to predict musculoskeletal deconditioning and determine appropriate exercise countermeasures associated with extended exposure to hypogravity. OBJECTIVES: The aim of this paper is to define an experimental protocol and methodology suitable to estimate in high-fidelity hypogravity conditions the lower limb internal joint reaction forces. State-of-the-art movement kinetics, kinematics, muscle activation and muscle-tendon unit behaviour during locomotor and plyometric movements will be collected and used as inputs (Objective 1), with musculoskeletal modelling and an optimisation framework used to estimate lower limb internal joint loading (Objective 2). METHODS: Twenty-six healthy participants will be recruited for this cross-sectional study. Participants will walk, skip and run, at speeds ranging between 0.56-3.6 m/s, and perform plyometric movement trials at each gravity level (1, 0.7, 0.5, 0.38, 0.27 and 0.16g) in a randomized order. Through the collection of state-of-the-art kinetics, kinematics, muscle activation and muscle-tendon behaviour, a musculoskeletal modelling framework will be used to estimate lower limb joint reaction forces via tracking simulations. CONCLUSION: The results of this study will provide first estimations of internal musculoskeletal loads associated with human movement performed in a range of hypogravity levels. Thus, our unique data will be a key step towards modelling the musculoskeletal deconditioning associated with long term habitation on the Lunar surface, and thereby aiding the design of Lunar exercise countermeasures and mitigation strategies.

Introducing the Concept of Exercise Holidays for Human Spaceflight - What Can We Learn From the Recovery of Bed Rest Passive Control Groups.

In an attempt to counteract microgravity-induced deconditioning during spaceflight, exercise has been performed in various forms on the International Space Station (ISS). Despite significant consumption of time and resources by daily exercise, including around one third of astronauts' energy expenditure, deconditioning-to variable extents-are observed. However, in future Artemis/Lunar Gateway missions, greater constraints will mean that the current high volume and diversity of ISS in-flight exercise will be impractical. Thus, investigating both more effective and efficient multi-systems countermeasure approaches taking into account the novel mission profiles and the associated health and safety risks will be required, while also reducing resource requirements. One potential approach is to reduce mission exercise volume by the introduction of exercise-free periods, or "exercise holidays". Thus, we hypothesise that by evaluating the 'recovery' of the no-intervention control group of head-down-tilt bed rest (HDTBR) campaigns of differing durations, we may be able to define the relationship between unloading duration and the dynamics of functional recovery-of interest to future spaceflight operations within and beyond Low Earth Orbit (LEO)-including preliminary evaluation of the concept of exercise holidays. Hence, the aim of this literature study is to collect and investigate the post-HDTBR recovery dynamics of current operationally relevant anthropometric outcomes and physiological systems (skeletal, muscular, and cardiovascular) of the passive control groups of HDTBR campaigns, mimicking a period of 'exercise holidays', thereby providing a preliminary evaluation of the concept of 'exercise holidays' for spaceflight, within and beyond LEO. The main findings were that, although a high degree of paucity and inconsistency of reported recovery data is present within the 18 included studies, data suggests that recovery of current operationally relevant outcomes following HDTBR without exercise-and even without targeted rehabilitation during the recovery period-could be timely and does not lead to persistent decrements differing from those experienced following spaceflight. Thus, evaluation of potential exercise holidays concepts within future HDTBR campaigns is warranted, filling current knowledge gaps prior to its potential implementation in human spaceflight exploration missions.

Falls Among People With Bilateral Vestibulopathy: A Review of Causes, Incidence, Injuries, and Methods.

Importance: People with bilateral vestibulopathy experience severe balance and mobility issues. Fear and anxiety are associated with reduced activity, which can further affect balance and fall risk. Understanding and intervening on falls in this population is essential. The aims of this narrative review are to provide an overview of the current knowledge and applied methods on fall incidence, causes, and injuries in bilateral vestibulopathy. Observations: Eleven articles reporting falls incidence in people with bilateral vestibulopathy were deemed eligible, including 3 prospective and 8 retrospective studies, with a total of 359 participants, of whom 149 (42%) fell during the assessed period. When reported, the most common perceived causes of falls were loss of balance, darkness, and uneven ground. Information on sustained injuries was limited, with bruises and scrapes being the most common, and only 4 fractures were reported. As most studies included falls as a secondary, descriptive outcome measure, fall data obtained using best practice guidelines were lacking. Only 6 studies reported their definition of a fall, of which 2 studies explicitly reported the way participants were asked about their fall status. Only 3 studies performed a prospective daily fall assessment using monthly fall diaries (a recommended practice), whereas the remaining studies retrospectively collected fall-related data through questionnaires or interviews. While most studies reported the number of people who did and did not fall, the number of total falls in individual studies was lacking. Conclusions and Relevance: The findings from this review suggest that falls in people with bilateral vestibulopathy are common but remain an understudied consequence of the disease. Larger prospective studies that follow best practice guidelines for fall data collection with the aim of obtaining and reporting fall data are required to improve current fall risk assessments and interventions in bilateral vestibulopathy.

Effect of age on treatment outcomes in benign paroxysmal positional vertigo: A systematic review.

BACKGROUND: Benign paroxysmal positional vertigo (BPPV) can lead to an increased fall risk in older adults. Therefore, we examined the influence of age on the effectiveness of canalith-repositioning procedures (CRPs) for the treatment of BPPV. METHODS: Pubmed, Web of Science, and the bibliographies of selected articles were searched for studies conducted before September 2020 that examined the effectiveness of treatments for BPPV in various age groups. Meta-analyses were performed to compare treatment effectiveness and recurrence rates for younger and older adults. Odds ratios were calculated in a random-effects model. Mean differences were calculated using a fixed-effects model. A significance level of p < 0.05 (95% confidence interval) was set. The risk of bias and the methodological quality of all included articles were examined. RESULTS: Forty-five studies were retrieved after full-text screening, of which 29 studies were included for a qualitative review. The remaining 16 studies were eligible for inclusion in the meta-analysis (3267 participants with BPPV). The success rate of a single CRP was higher in the younger group (72.5% vs. 67%, p < 0.001). An average of 1.4 and 1.5 CRPs was needed for complete recovery in the younger and older groups, respectively (p = 0.02). However, global treatment success did not differ between these groups (97.5% vs. 94.6%, p = 0.41). The recurrence rate was higher in the older population (23.2% vs. 18.6%, p = 0.007). CONCLUSIONS: Although more CRPs are needed, the rate of complete recovery in older adults is similar to that observed in younger adults.

The Relationship Between the Activities-Specific Balance Confidence Scale and Balance Performance, Self-perceived Handicap, and Fall Status in Patients With Peripheral Dizziness or Imbalance.

OBJECTIVE: Describe the relationship between the Activities-Specific Balance Confidence (ABC) scale and Dizziness Handicap Inventory (DHI) with balance performance, as well as fall status in patients with peripheral vestibular disorders. STUDY DESIGN: Retrospective. SETTING: Outpatient balance clinic, tertiary referral center. PATIENTS: Data from 97 patients (age: 54.8 ±â€Š12.3 yrs; 48 women) with dizziness or imbalance symptoms of peripheral vestibular origin were used for analysis. INTERVENTIONS: /. MAIN OUTCOME MEASURES: ABC-scores, DHI-scores, static and dynamic balance tests, and fall status of the past 4 weeks, 2 months, and 6 months before the time of measurement were collected. Spearman's rho correlations, χ2 with post-hoc testing, and Kruskal-Wallis with post-hoc Mann-Whitney U test results were interpreted. RESULTS: The ABC- and DHI-scores show moderate correlations with static balance (ABC: r = 0.44; DHI: r = -0.34) and dynamic balance tests (ABC: r = [-0.47;0.56]; DHI: r = [-0.48;0.39]) and a strong inverse correlation with each other (ABC: 70 ±â€Š25; DHI: 33 ±â€Š26; r = -0.84). Related to fall status, weak correlations were found (ABC: r = [-0.29;-0.21]; DHI: r = [0.29;0.33]). Additional results show that subjects in the low-level functioning (ABC) or severe self-perceived disability (DHI) categories have a poorer balance assessed by standing balance, Timed-Up-and-Go and Functional Gait Assessment and are more likely to have experienced multiple falls. CONCLUSIONS: The ABC-scale and DHI showed a strong convergent validity, additionally the ABC-scale showed a better concurrent validity with balance performances and the DHI with fall history. In general, patients with peripheral vestibular impairments reporting a lower self-confidence or a more severe self-perceived disability show worse balance performances and a higher fall incidence.

Paving the Way Toward Distinguishing Fallers From Non-fallers in Bilateral Vestibulopathy: A Wide Pilot Observation.

Patients with bilateral vestibulopathy (BVP) present with unsteadiness during standing and walking, limiting their activities of daily life and, more importantly, resulting in an increased risk of falling. In BVP patients, falls are considered as one of the major complications, with patients having a 31-fold increased risk of falling compared to healthy subjects. Thus, highlighting objective measures that can easily and accurately assess the risk of falling in BVP patients is an important step in reducing the incidence of falls and the accompanying burdens. Therefore, this study investigated the interrelations between demographic characteristics, vestibular function, questionnaires on self-perceived handicap and balance confidence, clinical balance measures, gait variables, and fall status in 27 BVP patients. Based on the history of falls in the preceding 12 months, the patients were subdivided in a "faller" or "non-faller" group. Results on the different outcome measures were compared between the "faller" and "non-faller" subgroups using Pearson's chi-square test in the case of categorical data; for continuous data, Mann-Whitney U test was used. Performances on the clinical balance measures were comparable between fallers and non-fallers, indicating that, independent from fall status, the BVP patients present with an increased risk of falling. However, fallers tended to report a worse self-perceived handicap and confidence during performing activities of daily life. Spatiotemporal parameters of gait did not differ between fallers and non-fallers during walking at slow, preferred, or fast walking speed. These results may thus imply that, when aiming to distinguish fallers from non-fallers, the BVP patients' beliefs concerning their capabilities may be more important than the moderately or severely affected physical performance within a clinical setting. Outcome measures addressing the self-efficacy and fear of falling in BVP patients should therefore be incorporated in future research to investigate whether these are indeed able to distinguish fallers form non-fallers. Additionally, information regarding physical activity could provide valuable insights on the contextual information influencing behavior and falls in BVP.

An exploratory investigation on spatiotemporal parameters, margins of stability, and their interaction in bilateral vestibulopathy.

Integration of accurate vestibular, visual, and proprioceptive information is crucial in managing the centre of mass in relation to the base of support during gait. Therefore, bilateral loss of peripheral vestibular function can be highly debilitating when performing activities of daily life. To further investigate the influence of an impaired peripheral vestibular system on gait stability, spatiotemporal parameters, step-to-step variability, and mechanical stability parameters were examined in 20 patients with bilateral vestibulopathy and 20 matched healthy controls during preferred overground walking. Additionally, using a partial least squares analysis the relationship between spatiotemporal parameters of gait and the margins of stability was explored in both groups. Patients with bilateral vestibulopathy showed an increased cadence compared to healthy controls (121 ± 9 vs 115 ± 8 steps/min; p = 0.02; d = 0.77). In addition, although not significant (p = 0.07), a moderate effect size (d = 0.60) was found for step width variability (Coefficient of Variation (%); Bilateral vestibulopathy: 19 ± 11%; Healthy controls: 13 ± 5%). Results of the partial least squares analysis suggest that patients with peripheral vestibular failure implement a different balance control strategy. Instead of altering the step parameters, as is the case in healthy controls, they use the single and double support phases to control the state of the centre of mass to improve the mechanical stability.

SWEAT2 study: effectiveness of trunk training on muscle activity after stroke. A randomized controlled trial.

BACKGROUND: Trunk training after stroke is an effective method for improving trunk control, standing balance and mobility. The SWEAT2 study attempts to discover the underlying mechanisms leading to the observed mobility carry-over effects after trunk training. AIM: A secondary analysis investigating the effect of trunk training on muscle activation patterns, muscle synergies and motor unit recruitment of trunk and lower limbs muscles, aimed to provide new insights in gait recovery after stroke. DESIGN: Randomized controlled trial. SETTING: Monocentric study performed in the RevArte Rehabilitation Hospital (Antwerp, Belgium). POPULATION: Forty-five adults diagnosed with first stroke within five months, of which 39 completed treatment and were included in the analysis. METHODS: Participants received 16 hours of additional trunk training (N.=19) or cognitive training (N.=20) over the course of four weeks (1 hour, 4 times a week). They were assessed by an instrumented gait analysis with electromyography of trunk and lower limb muscles. Outcome measures were linear integrated normalized envelopes of the electromyography signal, the amount and composition of muscle synergies calculated by nonnegative matrix factorization and motor unit recruitment calculated, by mean center wavelet frequencies. Multivariate analysis with post-hoc analysis and statistical parametric mapping of the continuous curves were performed. RESULTS: No significant differences were found in muscle activation patterns and the amount of muscle synergies. In 42% of the subjects, trunk training resulted in an additional muscle synergy activating trunk muscles in isolation, as compared to 5% in the control group. Motor unit recruitment of the of trunk musculature showed decreased fast-twitch motor recruitment in the erector spinae muscle after trunk training: for the hemiplegic (t[37]=2.44, P=0.021) and non-hemiplegic erector spinae muscle (t[37]=2.36, P=0.024). CONCLUSIONS: Trunk training improves selective control and endurance of trunk musculature after sub-acute stroke. CLINICAL REHABILITATION IMPACT: What is new to the actual clinical rehabilitation knowledge is that: trunk training does not alter muscle activation patterns or the amount of muscle synergies over time; a decrease in fast-twitch motor recruitment in the erector spinae muscle was found during walking after trunk training; trunk training seems to increase the fatigue-resistance of the back muscles and enables more isolated activation.

Aging and the Relationship between Balance Performance, Vestibular Function and Somatosensory Thresholds.

OBJECTIVES: The objective of this study was two-fold: (1) To evaluate the impact of the physiological aging process on somatosensory, vestibular, and balance functions, and (2) To examine the extent to which age and somatosensory and vestibular functions can predict balance performance. MATERIALS AND METHODS: In this cross-sectional study, 141 asymptomatic subjects were assessed for touch pressure thresholds (TPT) with Semmes-Weinstein monofilaments (SWF), vibration thresholds (VT) with a neurothesiometer (NT) and a Rydel-Seiffer tuning fork 128Hz (RSTF). Horizontal vestibulo-ocular reflexes (HVOR gain and asymmetry) were assessed using the video Head Impulse Test (vHIT). A modified version of the Romberg test was used to assess standing balance and the Timed Up and Go test (TUG) and tandem gait (TG) to evaluate dynamic balance. RESULTS: Significant age effects were found for TPT, VT, and balance but not for HVOR gain or asymmetry. Standing balance was explained for 47.2% by age, metatarsal 1 (MT1) (NT), and heel (SWF). The variance in TUG performance was explained for 47.0% by age, metatarsal 5 (MT5) (SWF), and medial malleolus (MM) (NT). Finally, the variance in TG performance was predicted for 43.1% by age, MT1 (NT), HVOR gain, and heel (SWF). CONCLUSION: Among asymptomatic adult population, both somatosensation and balance performance deteriorate with aging. In contrast, HVOR remains rather constant with age, which is possibly explained by the process of vestibular adaptation. Furthermore, this study provides evidence that the VT, TPT, HVOR gain, and age partly predict balance performance. Still, further research is needed, especially with bigger samples in decades 8 and 9.

SWEAT2 Study: Effectiveness of Trunk Training on Gait and Trunk Kinematics After Stroke: A Randomized Controlled Trial.

OBJECTIVE: Trunk training after stroke is an effective method for improving mobility, yet underlying associations leading to the observed mobility carryover effects are unknown. The purposes of this study were to investigate the effectiveness of trunk training for gait and trunk kinematics and to find explanatory variables for the mobility carryover effects. METHODS: This study was an assessor-masked, randomized controlled trial. Participants received either additional trunk training (n = 19) or cognitive training (n = 20) after subacute stroke. Outcome measures were the Tinetti Performance-Oriented Mobility Assessment (POMA), the Trunk Impairment Scale, spatiotemporal gait parameters, center-of-mass excursions, and trunk and lower limb kinematics during walking. Multivariate analysis with post hoc analysis was performed to observe treatment effects. Correlation and an exploratory regression analysis were used to examine associations with the mobility carryover effects. RESULTS: Significant improvements after trunk training, compared with the findings for the control group, were found for the Trunk Impairment Scale, Tinetti POMA, walking speed, step length, step width, horizontal/vertical center-of-mass excursions, and trunk kinematics. No significant differences were observed in lower limb kinematics. Anteroposterior excursions of the trunk were associated with 30% of the variability in the mobility carryover effects. CONCLUSIONS: Carryover effects of trunk control were present during ambulation. Decreased anteroposterior movements of the thorax were the main variable explaining higher scores on the Tinetti POMA Gait subscale. However, the implementation and generalizability of this treatment approach in a clinical setting are laborious and limited, necessitating further research. IMPACT: Trunk training is an effective strategy for improving mobility after stroke. Regaining trunk control should be considered an important treatment goal early after stroke to adequately prepare patients for walking.

An investigation of the spatio-temporal parameters of gait and margins of stability throughout adulthood.

Age-related changes in the way of walking may induce changes in dynamic stability. Therefore, the relationship between age, spatio-temporal characteristics and margins of stability was examined. One hundred and five healthy adults aged between 20 and 89 years old were analysed on spatio-temporal characteristics and margins of stability using three-dimensional motion analysis. Subjects walked barefoot over a 12-m-long walkway at their preferred walking speed. Covariance among gait characteristics was reduced using a factor analysis, identifying domains of gait. The influence of age, gender, body mass index (BMI) and leg length on domains of gait and margins of stability was investigated using linear mixed models. A stepwise linear regression identified domains of gait predicting the variance in margins of stability. Four domains of gait explaining 74.17% of the variance were identified. Age had a significant influence on the medio-lateral margin of stability and the 'variability', 'pace' and 'base of support' domain. BMI significantly influenced the medio-lateral margin of stability; gender and leg length had no influence on either of the margins of stability. The 'base of support' domain predicted 26% of the variance in the medio-lateral margin of stability. When considering the margins of stability, especially when comparing multiple groups, age, BMI and spatio-temporal parameters should be taken into account.

A Systematic Review on Balance Performance in Patients With Bilateral Vestibulopathy.

OBJECTIVE: Patients with bilateral vestibulopathy (BVP) have severe balance deficits, but it is unclear which balance measures are best suited to quantify their deficits and approximate the diversity of their self-reports. The purpose of this study was to explore measures of balance control for quantifying the performance of patients with BVP related to different balance domains, allowing targeted assessment of response to intervention. METHODS: MEDLINE, Web of Science, and Embase were systematically searched on October 9, 2019. The Scottish Intercollegiate Guidelines Network checklist for case-control studies was applied to assess each individual study's risk of bias. Standardized mean differences (SMD) were calculated based on the extracted numeric data and reported according to the type of sensory perturbation in the balance tasks. RESULTS: Twelve studies (1.3%) met the eligibility criteria and were analyzed, including data of 176 patients with BVP, 196 patients with unilateral vestibulopathy, and 205 healthy controls between 18 and 92 years old. In general, patients with BVP were either unable to maintain (or had reduced) balance during tasks with multisensory perturbations compared with healthy controls (range of mean SMD = 1.52-6.92) and patients with unilateral vestibulopathy (range of absolute mean SMD = 0.86-1.66). CONCLUSIONS: During clinical assessment to quantify balance control in patients with BVP, tasks involving multisensory perturbations should be implemented in the test protocol. IMPACT: As patients with BVP show difficulties with movement strategies, control of dynamics, orientation in space, and cognitive processing, clinicians should implement these aspects of balance control in their assessment protocol to fully comprehend the balance deficits in these patients.

Trunk biomechanics during walking after sub-acute stroke and its relation to lower limb impairments.

BACKGROUND: Trunk function and lower limb strength seem to be the primary predictors for functional independence in acute stroke patients. Gaining a better understanding of their relationship during walking aids in the identification of intrinsic trunk control deficits and underlying lower limb deficits resulting in compensatory trunk movements. METHODS: Fifty-seven subjects with stroke and 57 age- and gender-matched subjects without disability were included. Participants underwent an instrumented gait analysis with a standard total body Plug-In-Gait model, a clinical examination of the lower limbs based on range of motion, strength, muscle tone and several clinical assessment scales such as the Trunk Impairment Scale, Tinetti test and Functional Ambulation Categories. Spatiotemporal parameters and joint angular time profiles were compared between healthy adults and stroke survivors with severe and mild to moderate lower limb impairments. Spm1d was used to compare the joint angular time profiles between groups. FINDINGS: Truncal deviations are present during hemiplegic walking, sub-acute stroke survivors walked with increased thoracic tilt, a neutral frontal position of the pelvis during stance, a pelvic hike during swing, and a more rotated position without crossing of the midline. Patients with more severe lower limb impairments had more pronounced deficits in truncal motion. INTERPRETATION: Setting accurate rehabilitation goals is of major importance during stroke, as well as understanding the underlying mechanisms and causes of the truncal impairments. Although more compensatory trunk deviations were seen in participants with severe lower limb impairments, they should not be considered as the sole contributor of trunk impairments during walking. Results of this study suggest that intrinsic trunk deficits during walking are also present after stroke.

Prospective cohort study on the predictors of fall risk in 119 patients with bilateral vestibulopathy.

OBJECTIVES: To identify predictive factors for falls in patients with bilateral vestibulopathy (BV). Specific variables contributing to the general work-up of a vestibular patient were compared between BV patients experiencing falls and those who did not. DESIGN: Prospective multi-centric cohort study. SETTING: Department of Otorhinolaryngology & Head and Neck Surgery at two tertiary referral centers: Antwerp University Hospital and Maastricht University Medical Center. PARTICIPANTS: In total, 119 BV patients were included. BV diagnosis was defined in accordance with the diagnostic BV criteria, established by the Bárány Society in 2017. MAIN OUTCOME MEASURES: Patients were divided into fallers and non-fallers, depending on the experience of one or more falls in the preceding 12 months. Residual vestibular function on caloric testing, rotatory chair testing, video head impulse test (vHIT) and cervical vestibular evoked myogenic potentials (cVEMP) was evaluated as a predictive factor for falls. Furthermore, hearing function (speech perception in noise (SPIN)), sound localization performance, etiology, disease duration, sport practice, scores on the Dizziness Handicap Inventory (DHI) and the Oscillopsia Severity Questionnaire (OSQ) were compared between fallers and non-fallers. RESULTS: Forty-five (39%) patients reported falls. In a sub-analysis in the patients recruited at UZA (n = 69), 20% experienced three or more falls and three patients (4%) suffered from severe fall-related injuries. The DHI score and the OSQ score were significantly higher in fallers. Residual vestibular function, SPIN, sound localization performance, etiology, disease duration, age and sport practice did not differ between fallers and non-fallers. CONCLUSIONS: Falls and (severe) fall-related injuries are frequent among BV patients. A DHI score > 47 and an OSQ score > 27.5 might be indicative for BV patients at risk for falls, with a sensitivity of 70% and specificity of 60%. Residual vestibular function captured by single vestibular tests (vHIT, calorics, rotatory chair, cVEMP) or by overall vestibular function defined as the number of impaired vestibular sensors are not suitable to distinguish fallers and non-fallers in a BV population.

Stimulating balance: recent advances in vestibular stimulation for balance and gait.

Noisy galvanic vestibular stimulation (nGVS) can boost vestibular sensory thresholds via stochastic resonance and research on nGVS as an intervention for vestibulopathy has accelerated recently. Recent research has investigated the effects and associated mechanisms of nGVS on balance and gait. nGVS has potential as an intervention for balance and gait-related deficits in vestibulopathy, but further research into the mechanisms underlying these effects and consensus on stimulation protocols are required.