Effects of Task Demands on Postural Control in Children of Different Ages: A Cross-Sectional Study

This study evaluates the effect of dual tasks on balance during manipulation of visual information, the base of support, and cognitive tasks in 7–12-year-old children and adults. An equal number of girls (210) and boys (210) were selected from the schools by the cluster random sampling method (within the 7–12 age groups). Twenty young adults were also selected. Postural sway (PS) was measured in the anterior–posterior (AP) and mediolateral (ML) directions using a force plate in eight standing positions, including standing with closed eyes versus standing with open eyes and standing with feet together versus on a single limb, under the interference of cognitive dual tasks (DT) or a single task (ST). PS was found to decrease with advancing age. PS was also greater in men than women in both AP and ML directions (p < 0.05). PS was greater in the 7–12-year-old participants compared to adults under the manipulation of the base of support (p < 0.05). However, PS increased in all participants regardless of their age while manipulating both the base of support and visual information (p < 0.05). Children (within the 9–12 years age range) and adults could keep their balance while performing basic tasks; however, children had difficulty in maintaining their balance with higher task demands.

COVID and Post COVID Physical Therapy of a 63-year-old male with affection of Balance: A Case Report

Background: The global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease 2019 (COVID-19) has a harsh effect throughout the world. A wide range of neuromuscular symptoms including myalgia, anosmia, loss of taste and muscle weakness have been seen post COVID-19 infection. Some of these symptoms may impair balance and activities of daily living. Balance is defined as ability of an individual to maintain the line of gravity within the base of support. Objective: This case report study shows how physiotherapy management was helpful for a 63-year-old male during COVID and post-COVID rehabilitation to enhance his functional recovery. It also describes balance training strategies which were used in addition to regular pulmonary physiotherapy in a patient affected with COVID-19. Case Study: This study reports a four-month long physiotherapy protocol of a 63-year-old male patient admitted to a hospital due to COVID-19 in whom imbalance was also observed. Physiotherapy management was started for the same. The protocol included in-patient as well as out-patient exercises. Pulmonary physiotherapy along with neuro physiotherapy, in the form of balance training, were included. The patient showed good improvement in balance and regained his functional independence and hence discharged from physiotherapy treatment. Conclusion: Thus, Covid and post- COVID-19 physiotherapy rehabilitation is essential to elicit positive adaptive changes to improve the functional capacity, independence in the daily activities and QOL. KEY WORDS COVID-19, Static Balance, Dynamic Balance, Fatigue, Neuromuscular Disorders.

Characterization of Anticipatory Postural Adjustments in Lateral Stepping: Impact of Footwear and Lower Limb Preference

Lateral stepping is a motor task that is widely used in everyday life to modify the base of support, change direction, and avoid obstacles. Anticipatory Postural Adjustments (APAs) are often analyzed to describe postural preparation prior to forward stepping, however, little is known about lateral stepping. The aim of the study is to characterize APAs preceding lateral steps and to investigate how these are affected by footwear and lower limb preference. Twenty-two healthy young participants performed a lateral step using both their preferred and non-preferred leg in both barefoot and shod conditions. APA spatiotemporal parameters (size, duration, and speed) along both the anteroposterior and mediolateral axes were obtained through force plate data. APAs preceding lateral stepping showed typical patterns both along the anteroposterior and mediolateral axis. RM-ANOVA highlighted a significant effect of footwear only on medio-lateral APAs amplitude (p = 0.008) and velocity (p = 0.037). No differences were found for the limb preference. APAs in lateral stepping presented consistent features in the sagittal component, regardless of limb/shoe factors. Interestingly, the study observed that footwear induced an increase in the medio-lateral APAs size and velocity, highlighting the importance of including this factor when studying lateral stepping.

Small Directional Treadmill Perturbations Induce Differential Gait Stability Adaptation

Introducing unexpected perturbations to challenge gait stability is an effective approach to investigate balance control strategies. Little is known about the extent to which people can respond to small perturbations during walking. This study aimed to determine how subjects adapted gait stability to multidirectional perturbations with small magnitudes applied on a stride-by-stride basis. Ten healthy young subjects walked on a treadmill that either briefly decelerated belt speed ("stick"), accelerated belt speed ("slip"), or shifted the platform medial-laterally at right leg mid-stance. We quantified gait stability adaptation in both anterior-posterior and medial-lateral directions using margin of stability and its components, base of support and extrapolated center of mass. Gait stability was disrupted upon initially experiencing the small perturbations as margin of stability decreased in the stick, slip, and medial shift perturbations and increased in the lateral shift perturbation. Gait stability metrics were generally disrupted more for perturbations in the coincident direction. Subjects employed both feedback and feedforward strategies in response to the small perturbations, but mostly used feedback strategies during adaptation. Subjects primarily used base of support (foot placement) control in the lateral shift perturbation and extrapolated center of mass control in the slip and medial shift perturbations. These findings provide new knowledge about the extent of gait stability adaptation to small magnitude perturbations applied on a stride-by-stride basis and reveal potential new approaches for balance training interventions to target foot placement and center of mass control.

Theoretical Rationale for Design of Tasks in a Virtual Reality-Based Exergame for Rehabilitation Purposes

Virtual reality games are playing a greater role in rehabilitation settings. Previously, commercial games have dominated, but increasingly, bespoke games for specific rehabilitation contexts are emerging. Choice and design of tasks for VR-games are still not always clear, however; some games are designed to motivate and engage players, not necessarily with the facilitation of specific movements as a goal. Other games are designed specifically for the facilitation of specific movements. A theoretical background for the choice of tasks seems warranted. As an example, we use a game that was designed in our lab: VR Walk. Here, the player walks on a treadmill while wearing a head-mounted display showing a custom-made virtual environment. Tasks include walking on a glass bridge across a drop, obstacle avoidance, narrowing path, walking in virtual footsteps, memory, and selection tasks, and throwing and catching objects. Each task is designed according to research and theory from movement science, exercise science, and cognitive science. In this article, we discuss how for example walking across a glass bridge gives perceptual challenges that may be suitable for certain medical conditions, such as hearing loss, when perceptual abilities are strained to compensate for the hearing loss. In another example, walking in virtual footsteps may be seen as a motor and biomechanical constraint, where the double support phase and base of support can be manipulated, making the task beneficial for falls prevention. In a third example, memory and selection tasks may challenge individuals that have cognitive impairments. We posit that these theoretical considerations may be helpful for the choice of tasks and for the design of virtual reality games.

The ability to increase the base of support and recover stability is limited in its generalisation for different balance perturbation tasks

Background The assessment of stability recovery performance following perturbations contributes to the determination of fall resisting skills. This study investigated the association between stability recovery performances in two perturbation tasks (lean-and-release versus tripping). Methods Healthy adults (12 young: 24 ± 3 years; 21 middle-aged: 53 ± 5 years; 11 old: 72 ± 5 years) were suddenly released from a forward-inclined position attempting to recover stability with a single step. In a second task, all participants experienced a mechanically induced trip during treadmill walking. To assess dynamic stability performance, the antero-posterior margin of stability (MoS), the base of support (BoS), and the rate of increase in BoS were determined at each foot touchdown (TD) for both tasks. Results Only weak to moderate correlations in dynamic stability performance parameters were found between the two tasks (0.568 > r > 0.305, 0.001 < p < 0.04). A separation of participants according to the number of steps required to regain stability in the lean-and-release task revealed that multiple- (more than one step) compared to single-steppers showed a significantly lower MoS at TD (p = 0.003; g = 1.151), lower BoS at TD (p = 0.019; g = 0.888) and lower rate of increase in BoS until TD (p = 0.002; g = 1.212) after release. Despite these profound subgroup differences in the lean-and-release task, no differences between multiple- and single-steppers were observed in the stability recovery performance during tripping. Conclusion The results provide evidence that the ability to effectively control dynamic stability following a sudden balance disturbance in adults across a wide age range is limited in its generalisation for different perturbation tasks.

Evidence for constancy in the modularity of trunk muscle activity preceding reaching: Implications for the role of preparatory postural activity.

Postural muscle activity precedes voluntary movements of the upper limbs. The traditional view of this activity is that it anticipates perturbations to balance caused by the movement of a limb. However, findings from reach-based paradigms have shown that postural adjustments can initiate center of mass displacement for mobility, rather than minimize its displacement for stability. Within this context, altering reaching distance beyond the base of support would place increasing constraints on equilibrium during stance. If the underlying composition of anticipatory postural activity is linked to stability, coordination between muscles (i.e., motor modules) may evolve differently as equilibrium constraints increase. We analyzed the composition of motor modules in functional trunk muscles as participants performed multi-directional reaching movements to targets within and beyond arm's length. Bilateral trunk and reaching arm muscle activity were recorded. Despite different trunk requirements necessary for successful movement, and the changing biomechanical (i.e. postural) constraints that accompany alterations in reach distance, Non-negative Matrix Factorization identified functional motor modules derived from preparatory trunk muscle activity that shared common features. Relative similarity in modular weightings (i.e., composition) and spatial activation profiles that reflect movement goals across tasks necessitating differing levels of trunk involvement provides evidence that preparatory postural adjustments are linked to the same task priorities (i.e. movement generation rather than stability).

Research Note on Experiences and Attitudes Going Forward with and Beyond Delta (Version 1: late-September1 )

The attitudinal base of support for the current ‘elimination strategy’ regime in NZ is assessed using current and recent survey data – covering attitudes and reports in relation to social distancing and mask wearing, to the boundary, and the lockdown and its effects. Evidence is compiled, too, on attitudes towards any resetting of New Zealand’s Covid regime and possible pivots to alternatives.

RELATIONSHIP OF PELVIC ALIGNMENT WITH BALANCE AND GAIT IN PATIENTS WITH STROKE: A SYSTEMATIC REVIEW

Background- Pelvis is the key structure that connects the spine and the lower limbs. Altered Pelvic Alignment and asymmetrical weight bearing on affected lower limbs is a common problem leading to pelvic instability which may have an effect on balance and gait in patients with stroke. Hence, it was aimed to investigate the interdependence of these three components in patients with stroke. Methods- Four databases (PubMed, Google Scholar, Cochrane, Science Direct) were searched to identify eligible studies using the keywords Pelvic Alignment, Gait, Balance, Stroke. Only observational studies published in last 10 years (2010-2020) were included in this review. Results- Thirteen studies were included in the review conducted on sub-acute and chronic stage. All studies investigated the affection of pelvic mal-alignment, balance and gait in combination of two variables except 3 studies which investigated the combined effect of pelvic inclination on both balance and gait. The abnormal pelvic tilt results in lateral displacement of the pelvis on affected side, altered Base of Support, reduced balance control, asymmetry in weight bearing leading to altered gait. Conclusion- Pelvic tilt, anterior and lateral has a significant impact on static balance, gait variables, weight bearing symmetry.