Neurofeedback vibrotactile system for parkinsonians overcome freezing of gait first steps in detecting the most perceived frequency

Parkinson’s Disease is a neurodegenerative disorder for which there is still no cure affecting the non-motor and motor systems. One of the most serious gait disorders are the freezing episodes, denominated by freezing of gait. This paper address the development and validation of a neurofeedback vibrotactile system through a belt for patients with Parkinson’s Disease overcome the freezing episodes, aiming to detect the most perceived frequency. It was verified that the higher frequencies (above 160 Hz) are easily perceived independently of the time interval of vibrotactile feedback.This work is supported by the FCT – Fundação para a Ciência e Tecnologia - with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 - Programa Operacional Competitividade e Internacionalização (POCI) - with the reference project POCI-01- 0145-FEDER-00694

Perception of Time-Discrete Haptic Feedback on the Waist is Invariant with Gait Events

The effectiveness of haptic feedback devices highly depends on the perception of tactile stimuli, which differs across body parts and can be affected by movement. In this study, a novel wearable sensory feedback apparatus made of a pair of pressure-sensitive insoles and a belt equipped with vibrotactile units is presented; the device provides time-discrete vibrations around the waist, synchronized with biomechanically-relevant gait events during walking. Experiments with fifteen healthy volunteers were carried out to investigate users' tactile perception on the waist. Stimuli of different intensities were provided at twelve locations, each time synchronously with one pre-defined gait event (i.e. heel strike, flat foot or toe off), following a pseudo-random stimulation sequence. Reaction time, detection rate and localization accuracy were analyzed as functions of the stimulation level and site and the effect of gait events on perception was investigated. Results revealed that above-threshold stimuli (i.e. vibrations characterized by acceleration amplitudes of 1.92g and 2.13g and frequencies of 100 Hz and 150 Hz, respectively) can be effectively perceived in all the sites and successfully localized when the intertactor spacing is set to 10 cm. Moreover, it was found that perception of time-discrete vibrations was not affected by phase-related gating mechanisms, suggesting that the waist could be considered as a preferred body region for delivering haptic feedback during walking

Haptic wearables as sensory replacement, sensory augmentation and trainer - a review

Sensory impairments decrease quality of life and can slow or hinder rehabilitation. Small, computationally powerful electronics have enabled the recent development of wearable systems aimed to improve function for individuals with sensory impairments. The purpose of this review is to synthesize current haptic wearable research for clinical applications involving sensory impairments. We define haptic wearables as untethered, ungrounded body worn devices that interact with skin directly or through clothing and can be used in natural environments outside a laboratory. Results of this review are categorized by degree of sensory impairment. Total impairment, such as in an amputee, blind, or deaf individual, involves haptics acting as sensory replacement; partial impairment, as is common in rehabilitation, involves haptics as sensory augmentation; and no impairment involves haptics as trainer. This review found that wearable haptic devices improved function for a variety of clinical applications including: rehabilitation, prosthetics, vestibular loss, osteoarthritis, vision loss and hearing loss. Future haptic wearables development should focus on clinical needs, intuitive and multimodal haptic displays, low energy demands, and biomechanical compliance for long-term usage

Somatosensory stimulation to improve lower-limb recovery after stroke

Introduction Increasing lower-limb sensation could improve walking post-stroke but evidence for this is limited. This thesis reports: 1) Review of published literature on somatosensory stimulation of the foot to enhance lower-limb function post-stroke. 2) Development of standardised intervention protocols for testing in a feasibility trial. 3) Feasibility trial of somatosensory stimulation interventions combined with functional activity. Methods 1) Systematic review with narrative synthesis of somatosensory stimulation to the foot to improve balance and gait post-stroke. 2) Modified Nominal Group Technique with experienced therapists, informed by literature, to develop and seek consensus on three standardised therapy protocols. a) lower-limb mobilization and tactile stimulation (MTS) b) textured insole wearing (TI) c) task-specific gait training (TSGT) 3) Mixed-methods, single-blind feasibility study explored: recruitment, participant characteristics, attrition, intervention and outcome measures acceptability (responses, feasibility, costs), sample size requirements, and participants’ experiences. Adults 42–112 days post-stroke were randomized to either TIs+TSGT or MTS+TSGT. Lower-limb sensorimotor and functional outcomes were measured pre-randomization, post-intervention, and one-month later. Participants’ experiences and acceptability of interventions and outcomes were explored in focus groups, with qualitative data analysed thematically. Quantitative feasibility outcomes were analysed using descriptive statistics, and within-group changes calculated. Results 1) Seventeen trials included in the review confirmed that evidence for somatosensory stimulation to improve lower-limb function post-stroke is limited. 2) Validated trial intervention protocols for MTS, TIs and TSGT were developed, with consensus. 3) Thirty-four stroke survivors were recruited and completed the trial, with acceptable recruitment (48.57%) and attrition (5.88%) rates. Feasibility of outcomes, costs, delivery and acceptability of interventions and outcome measures were confirmed. Potential response to treatment was noted. Conclusion Somatosensory stimulation of the foot post-stroke warrants investigation. Feasibility of a larger trial of somatosensory stimulation interventions was confirmed. Participant characteristics, response over time, and variance of outcome measures will inform a future larger trial

The effect of aging, obesity and diabetes on foot health and its association with current and future footwear technologies

Changes in foot health trends are beginning to demand significant changes to foot health provision globally, for which appropriate provision to retail and health services is key. With the right input to innovation and design, footwear can help keep us fit and active and contribute to our overall wellbeing, creating exciting opportunities for the footwear market. Likewise, the development of orthotic materials, designs and manufacturing processes is enabling more complex solutions to equally complex developing foot conditions. There are three key issues driving the demand for specific footcare; the global increase in the number of people with diabetes, those who are obese and the fact we are all living longer. The populations of diabetic, elderly and obese adults require specific footcare solutions to meet the specific characteristics of their foot health issues such as wider-fit footwear and pressure relieving orthotic materials. Characteristics of these populations' feet relating to their morphology, tissue characteristics, vascular supply and sensation impact on their requirements from footwear. Additional characteristics relating to their overall health such as excess mass and instability additionally impact on the wear on the loading of the footwear and design features which may be beneficial

The Effects of Somatosensory Input on Gait in Individuals Post-Stroke

Background and Purpose: Stroke is a leading cause of disability that results in various neurological deficits, one of which is hemiplegia. This deficit alters the gait cycle, resulting in decreased propulsion force by plantar flexor muscles, decreased activation of dorsiflexor (DF) muscles, and increased coactivation of antagonistic ankle muscles. Stroke also leads to altered somatosensory input which results in decreased balance and gait speed, ultimately increasing fall risk. Therapies targeting increased somatosensory input have been shown to be beneficial in stroke as well as other neurological populations. However, no known studies have investigated the acute effects of local vibration to the plantar side of the foot. Our study aims to investigate the effect of vibratory insoles, referred to as tactor insoles, on propulsion forces, ankle joint kinematics and muscle activation in individuals with chronic post-stroke hemiparesis. Subjects: Fifteen participants with chronic stroke and fifteen age-similar, non-neurologically impaired participants were recruited. Inclusion criteria included \u3e6 months post-stroke with hemiparesis and ability to walk without an assistive device for 2 minutes. Exclusion criteria included cerebellar stroke and/or inability to walk without an assistive device for more than 2 minutes. Methods: All participants underwent assessment of anthropometrics, Lower Extremity Fugl-Meyer, and a 2-minute walk test. A 3-D motion capture system and instrumented treadmill were used to obtain lower extremity kinematics and propulsive/braking force profiles. Co-contraction index of lower leg musculature (tibialis anterior and medial gastrocnemius) electromyography was also obtained. Participants were asked to walk with No Tactor (NT) at a self-selected speed and then were randomly assigned to 4 different tactor vibration conditions (Bilateral Off [BOFF], Bilateral On {BON], Ipsilateral On [ION], and Contralateral On [CON]) at the same walking speed. A 3x5 mixed factorial ANOVA was used to compare each outcome variable between 3 legs and between the 5 tactor conditions. The 3 legs examined were paretic limb of participant post-stroke, non-paretic limb of participant post-stroke, and non-impaired limb of non-neurologically impaired individuals. Results: There was a significant interaction of limb and condition on ankle angle at heel strike. In the paretic limb, ankle dorsiflexion at heel strike was greater for ION and CON conditions when compared to NT condition. There was a significant main effect of limb for peak propulsive force, propulsive impulse, peak braking force, braking impulse, and ankle angle at toe-off. When five tactor conditions were combined, we observed that the paretic limb exhibited significantly less peak propulsive force, propulsive impulse, peak braking force, and braking impulse. A significant main effect of condition was found for peak braking force, ankle angle at toe-off, and peak plantarflexion during swing. When compared to NT condition, 3 limbs being combined showed that peak braking force was greater at BON condition, ankle plantarflexion at toe-off was smaller at BOFF condition, and peak plantarflexion during swing was smaller at BON condition. Discussion: We observed that gait in post-stroke individuals can be acutely modified by adding additional somatosensory input, particularly for ankle dorsiflexion at heel strike

Textured shoe insoles to improve balance performance in adults with diabetic peripheral neuropathy: study protocol for a randomised controlled trial

IntroductionPeripheral neuropathy is a major risk factor for falls in adults with diabetes. Innovative footwear devices which artificially manipulate the sensory environment at the feet, such as textured shoe insoles, are emerging as an attractive option to mitigate balance and walking problems in neuropathic populations. This study aims to explore whether wearing textured insoles for 4 weeks alters balance performance in adults with diabetic peripheral neuropathy.Methods and analysisA prospective, single-blinded randomised controlled trial with parallel groups will be conducted on 70 adults with diabetic peripheral neuropathy. Adults with a diagnosis of peripheral neuropathy (secondary to type 2 diabetes), aged ≥18 years, ambulant over 20 m (with/without an assistive device), will be recruited. Participants will be randomised to receive a textured insole (n=35) or smooth insole (n=35), to be worn for 4 weeks. During baseline and post intervention assessments, standing balance (foam/firm surface; eyes open/closed) and walking tasks will be completed barefoot, wearing standard shoes only, and two different insoles (smooth, textured). The primary outcome measure will be centre of pressure (CoP) velocity, with higher values indicating poorer balance. Secondary outcome measures include walking quality (gait velocity, base of support, stride length and double-limb support time), physical activity levels, foot sensation (light-touch pressure, vibration) and proprioception (ankle joint position sense), and other balance parameters (CoP path length, anteroposterior and mediolateral excursion). Patient-reported outcomes will be completed evaluating foot health, frequency of falls and fear of falling. Data will be analysed using a repeated measures mixed models approach (including covariates) to establish any differences between-groups, for all outcome measures, over the intervention period.Ethics and disseminationEthical approval has been obtained from the institutional Human Research Ethics Committee (#2017000098). Findings will be disseminated at national and international conferences, through peer-reviewed journals, workshops and social media.Trial registration numberACTRN12617000543381; Pre-results.</jats:sec