Sensory Electrical Stimulation Research Articles

Effects Of Sensory Training and Electrical Stimulation on Sole of The Foot Sensations in Patients With Acute Hemiplegia

Effects Of Sensory Training and Electrical Stimulation on Sole of The Foot Sensations in Patients With Acute Hemiplegia

Effects of Sensory Flicker and Electrical Flicker Stimulation.

Effects of Sensory Flicker and Electrical Flicker Stimulation.

Sensory mapping of lumbar facet joint pain: a feasibility study.

To evaluate the feasibility of sensory mapping of lumbar facet joint pain in patients scheduled to undergo radiofrequency (RF) denervation. Prospective cohort study. University teaching hospital. A total of 15 participants listed for RF denervation of lumbar facet joint. After written informed consent, participants were recruited to the study. Participants completed a pain diagram prior to their procedure. After successful image-guided placement of RF cannulas, the sensory detection threshold using 50 Hz stimulation was obtained, followed by application of suprathreshold stimulation. Participants mapped their stimulated area in comparison to their pre-procedure pain diagram. All 15 participants had previously undergone diagnostic blocks. All participants were able to report either pain or paraesthesia during suprathreshold stimulation. In total, 14 out of 15 participants reported complete coverage of their usual painful area with suprathreshold stimulation of nerves scheduled for RF denervation. In one of the participants, an area of upper lumbar pain was not covered during suprathreshold stimulation. Nearly two-thirds of the participants (n = 9), reported either pain or paraesthesia, outside their normal painful area during suprathreshold stimulation. A total of 71 nerves were scheduled for RF denervation. Sensory electrical stimulation was successfully achieved in 68 out of 71 nerves (96%). The average sensory detection threshold was found to be 0.3 V while the suprathreshold stimulation was 0.6 V. Lumbar facet joint pain can be mapped using suprathreshold sensory stimulation, which has the potential to introduce objectivity during RF denervation.

EFFECT OF SENSORY ELECTRICAL STIMULATION ON RESTING TREMORS IN PATIENTS WITH PARKINSON’S DISEASE AND SWEDDs

Patients with scans without evidence of dopaminergic deficits (SWEDDs) show symptoms (e.g., tremors) similar to those of Parkinson’s disease (PD) patients, so they are often misdiagnosed. Sensory electrical stimulation (SES) was reported to suppress essential tremor in patients, but SES was never applied to patients with PD and SWEDDs. As the pathophysiological mechanisms of PD and SWEDDs are likely to be different, we hypothesized that the effect of SES would also be different in the two patient groups. This study aimed to test that hypothesis. Fourteen patients with PD and nine with SWEDDs participated in this study. Three wrist muscles were stimulated for 15[Formula: see text]s using SES with a stimulation intensity lower than the motor threshold. Angular motion of the index finger was measured via a triaxial gyrosensor before, during, and after stimulation. Outcome measures included the amplitude and peak frequency of the angular motion of the index finger. Tremor amplitude decreased during and after SES in patients with PD ([Formula: see text]). However, tremor amplitudes during and after SES were not different from the base level in SWEDDs patients. The peak frequency of tremors temporarily decreased during stimulation in PD patients, but not in SWEDDs patients. SES suppressed tremors in patients with PD, but not with SWEDDs. The results could help understand the pathophysiological differences of tremors between PD and SWEDDs.

A rat model of somatosensory-evoked reflex seizures induced by peripheral stimulation

ObjectiveWe introduce a novel animal model of somatosensory stimulation-induced reflex seizures which generates focal seizures without causing damage to the brain. MethodsSpecifically, we electrically stimulated digits or forepaws of adult rats sedated with dexmedetomidine while imaging cerebral blood volume and recording neurophysiological activity in cortical area S1FL. For the recordings, we either inserted a linear probe into the D3 digit representation or we performed surface electrocorticography (ECoG) recordings. ResultsPeripheral stimulation of a digit or the forepaw elicited seizures that were followed by a refractory period with decreased neuronal activity, or another seizure or normal response. LFP amplitudes in response to electrical pulses during the seizures (0.28 ± 0.03 mV) were higher than during normal evoked responses (0.25 ± 0.05 mV) and refractory periods (0.2 ± 0.08 mV). Seizures generated during the stimulation period showed prolonged after-discharges that were sustained for 20.9 ± 1.9 s following the cessation of the stimulus. High-frequency oscillations were observed prior to and during the seizures, with amplitudes higher than those associated with normal evoked responses. The seizures were initially focal. Optical imaging of the cerebral blood volume response showed that they propagated from the onset zone to adjacent cortical areas, beyond the S1FL representation of the stimulated digit or forepaw. The spatial extent during seizures was on average 1.74 times larger during the stimulation and 4.1 times following its cessation relative to normal evoked responses. Seizures were recorded not only by probes inserted into cortex but also with ECoG arrays (24.1 ± 5.8 seizures per rat) placed over the dura matter, indicating that the seizures were not induced by damage caused by inserting the probes to the cortex. Stimulation of the forepaw elicited more seizures (18.8 ± 8.5 seizures per rat) than stimulation of a digit (1.7 ± 0.7). Unlike rats sedated with dexmedetomidine, rats anesthetized with urethane showed no seizures, indicating that the seizures may depend on the use of the mild sedative dexmedetomidine. SignificanceOur proposed animal model generates seizures induced by electrical sensory stimulation free of artifacts and brain damage. It can be used for studying the mechanisms underlying the generation and propagation of reflex seizures and for evaluating antiepileptic drugs.

Safety of transcutaneous electrical sensory stimulation of the neck in terms of vital parameters in dysphagia rehabilitation

Transcutaneous electrical sensory stimulation (TESS) devices are approved for use in Japan, but their safety when used through the neck skin for dysphagia rehabilitation has not been reported. This study aimed to verify the safety of TESS use through the neck skin. Twenty patients (mean age 86.5 ± 5.1 years) with aspiration pneumonia undergoing dysphagia rehabilitation were included in this retrospective observational and matched control study. We compared vital signs in 10 subjects who underwent swallowing rehabilitation with the TESS device, and matched control patients over 7 days. The results were the following: tachycardia, 0.60 ± 1.07 vs. 0.70 ± 0.67 days; high blood pressure, 0.40 ± 0.70 vs. 0.50 ± 1.08 days; low blood pressure, 0.40 ± 0.70 vs. 0.10 ± 0.32 days; low oxygen saturation, 0.60 ± 1.58 vs. 0.50 ± 1.08 days, p = 0.870; oxygen administration, 0.80 ± 2.20 vs. 1.20 ± 2.15 days; tachypnea, 0.50 ± 0.71 vs. 0.50 ± 0.53 days; elevated body temperature, 2.00 ± 1.41 vs. 1.60 ± 1.96 days. There were no significant differences in clinical stability between the TESS and control groups of patients with aspiration pneumonia. TESS through the neck appears safe as an intervention in dysphagia rehabilitation.

Efeito da estimulação elétrica periférica e cerebral na força isométrica máxima dos extensores do joelho: ensaio clínico aleatorizado

INTRODUÇÃO: Recentes evidências têm demonstrado resultados bastante promissores para o uso de estratégias não invasivas de neuromodulação na melhora de habilidades físicas ou esportivas. A estimulação elétrica periférica (EEP) e a estimulação transcraniana por corrente contínua (ETCC) são técnicas não invasivas e não farmacológicas bastante utilizadas para modular a excitabilidade neuronal de áreas cortico-motoras e estimular a recuperação funcional. No entanto, poucos estudos têm investigado o efeito dessas técnicas na melhora do desempenho muscular. OBJETIVO: Investigar o efeito da estimulação elétrica periférica sensorial (EEPs) seguida de estimulação elétrica periférica motora (EEPm) ou estimulação transcraniana por corrente contínua (ETCC) na força isométrica máxima dos extensores do joelho em indivíduos saudáveis. MÉTODO: 20 universitários saudáveis foram distribuídos aleatoriamente em dois blocos distintos de 10 participantes cada: Bloco n°1 EEPs real + EEPm real ou EEPs simulada + EEPm real e bloco n°2 EEPs real + ETCC real ou EEPs simulada + ETCC real em uma única sessão. A contração voluntária isométrica máxima (CVIM) dos extensores do joelho foi avaliada por meio da dinamometria manual antes, durante e 10 min pós-estimulação. RESULTADOS: A CVIM dos extensores do joelho aumentou significativamente 10 minutos pós-ETCC isolada (diferença média = 0,23 N/Kg; IC 95% = 0,01 a 0,44 N/Kg; p = 0,04). A ETCC isolada também apresentou maior proporção cumulativa de respondedores seguido de EEPs+ETCC. CONCLUSÃO: A estimulação transcraniana por corrente contínua induz a aumentos significativos na CVIM em indivíduos saudáveis. No entanto, a aplicação prévia de estimulação elétrica periférica sensorial não impulsiona os efeitos da estimulação elétrica periférica motora ou cerebral na CVIM.

Development of a training paradigm for voluntary control of the peri-auricular muscles: a feasibility study

BackgroundSpinal cord injury (SCI) can lead to severe and permanent functional deficits. In humans, peri-auricular muscles (PAMs) do not serve any physiological function, though their innervation is preserved in even high level SCI. Auricular control systems provide a good example of leveraging contemporary technologies (e.g., sEMG controlled computer games) to enable those with disabilities. Our primary objective is to develop and test the effectiveness of an auricular muscle training protocol to facilitate isolated and coordinated, bilateral voluntary control that could be used in individuals without volitional control of the vestigial PAMs.MethodsSeventeen non-disabled persons were screened; 13 were eligible and 10 completed the entire protocol. The facilitation phase, included one session of sub-motor threshold, sensory electrical stimulation followed by neuromuscular electrical stimulation paired with ear movement feedback for up to 8 additional sessions. Participants progressed to the skill acquisition phase where they dawned an auricular control device that used sEMG signals to control movements of a cursor through three levels of computer games, each requiring increasingly more complex PAM coordination.ResultsThe 10 who completed the protocol, finished the facilitation phase in 3 to 9 sessions and achieved some level of voluntary auricle movement that ranged between 1 and 5 mm. Qualitative analysis of longitudinal post-session auricular movement, revealed two subgroups of learners. Six successfully completed all 3 games—the “Learners”. Two were partially successful in game completion and two were unable to complete a single game--“Poor/Non-Learners”. Quantitative analysis revealed a significant group difference in auricular amplitude for both facilitation and skill phases (p < .05), and a significant relationship between performance in the two phases (R2 = 0.84, p = 0.004).ConclusionSixty percent of those who completed the facilitation phase were able to learn and demonstrate functional voluntary control of the vestigial PAMs. Those who progressed the fastest through facilitation were also those who were most proficient in skill acquisition with the device. There was considerable variability in progression through the two-phase protocol, with 20% deemed Poor/Non-Learners and unable to complete even the most basic game following training. There were no serious adverse events.Trial registrationClinicalTrials.gov Identifier: NCT02358915, first posted February 9, 2015.

Sensory Amplitude Electrical Stimulation via Sock Combined With Standing and Mobility Activities Improves Walking Speed in Individuals With Chronic Stroke: A Pilot Study.

Objective: To determine if sensory amplitude electrical stimulation (SES) delivered via sock electrode combined with standing and mobility activities improved gait speed, sensation, balance, and participation in chronic stroke. It was hypothesized that SES would enhance the effectiveness of exercise, resulting in reduced impairment and improved function.Design: Case Series.Setting: Home-based intervention.Participants: Thirteen adults (56.5 + 7.84 years old) with chronic stroke (8.21 + 4.36 years post) and hemiparesis completed the study. Participants were community ambulators.Intervention: Participants completed 6 weeks of self-administered SES delivered via sock electrode concurrent with standing and mobility activities for a minimum of 5 days/week for 30-min, twice daily.Outcome Measures: Berg Balance Scale (BBS), Stroke Rehabilitation Assessment of Movement—LE subscale (STREAM), 10 Meter Walk Test (10 MWT), Activities-Specific Balance Confidence Scale (ABC), Stroke Impact Scale (SIS), Perceptual Threshold of Electrical Stimulation (PTTES), and Monofilament testing were administered at pre-test, post-test, and 3-month follow up.Results: Baseline sensory scores and change scores on functional outcomes were analyzed using Pearson Product-Movement Correlation Coefficients, Friedman test, and Linear mixed models. There was a significant change with 10 MWT self-selected pace (Friedman's p = 0.038). Pre-post intervention changes in other outcome measures were not significant. According to the Cohen's effect size classification, there were medium effect sizes for both the STREAM-LE and Monofilaments.Conclusion: The use of home-based SES via sock electrode combined with standing and mobility activities may contribute to improve gait speed in chronic stroke.

CONTINUOUS SENSORY ELECTRICAL STIMULATION FOR THE SUPPRESSION OF PARKINSONIAN REST TREMOR

This paper aims to investigate the effect of continuous sensory electrical stimulation (SES) on the suppression of a Parkinsonian rest tremor. Fourteen patients with Parkinson’s disease participated in this study. Three wrist muscles were electrically stimulated on sensory level under motor threshold. Intensity of stimulation was determined for each muscle of each patient as the maximum tolerable current amplitude that does not induce muscle contraction. Tri-axial gyro sensors were attached to three upper limb segments. The angular velocity of each segment was measured for each of the three sessions, i.e., PRE-, ON- and POST- stimulations. Outcome measures were the tremor amplitude and main frequency of each axis in the power spectrum. Decrease in tremor amplitude was significant at ON and POST sessions in finger and at POST session in hand and forearm. Decrease in main frequency was significant mainly at ON session. About one-third of patients showed reduction in tremor power at ON-stimulation and at POST-stimulation. Subjects with suppression of tremor showed greater initial tremor amplitude than those without suppression. Continuous SES suppressed the Parkinsonian rest tremor. The results suggest that the properties of tremor-generating loop may be altered by continuous SES and the effect lasts temporarily.

Sensory Electrical Stimulation Cueing May Reduce Freezing of Gait Episodes in Parkinson's Disease.

Introduction Freezing of gait (FoG) is a movement abnormality that presents with advancing Parkinson's disease (PD) and is one of the most debilitating symptoms of the disease. The mainstay of nonpharmacological management of FoG is typically through external cueing techniques designed to relieve or prevent the freezing episode. Previous work shows that electrical stimulation may prove useful as a gait guidance technique, but further evidence is required. The main objective of this study was to determine whether a “fixed” rhythmic sensory electrical stimulation (sES) cueing strategy would significantly (i) reduce the time taken to complete a walking task and (ii) reduce the number of FoG episodes occurring when performing the task. Methods 9 participants with idiopathic PD performed a self-identified walking task during both control (no cue) and cueing conditions. The self-identified walking task was a home-based daily walking activity, which was known to result in FoG for that person. A trained physiotherapist recorded the time taken to complete the walking task and the number of FoG episodes which occurred during the task. Data were analyzed by paired t-tests for both the time to complete a walking task and the number of FoG episodes occurring. Results sES cueing resulted in a reduction in the time taken to complete a walking task and in the number of FoG episodes occurring during performance of this task by 14.23 ± 11.15% (p=0.009) and 58.28 ± 33.89% (p=0.002), respectively. Conclusions This study shows a positive effect of “fixed” rhythmic sES on the time taken to complete a walking task and on the number of FoG episodes occurring during the task. Our results provide evidence that sES cueing delivered in a “fixed” rhythmic manner has the potential to be an effective cueing mechanism for FoG prevention.

Effects of 8-week sensory electrical stimulation combined with motor training on EEG-EMG coherence and motor function in individuals with stroke

The peripheral sensory system is critical to regulating motor plasticity and motor recovery. Peripheral electrical stimulation (ES) can generate constant and adequate sensory input to influence the excitability of the motor cortex. The aim of this proof of concept study was to assess whether ES prior to each hand function training session for eight weeks can better improve neuromuscular control and hand function in chronic stroke individuals and change electroencephalography-electromyography (EEG-EMG) coherence, as compared to the control (sham ES). We recruited twelve subjects and randomly assigned them into ES and control groups. Both groups received 20-minute hand function training twice a week, and the ES group received 40-minute ES on the median nerve of the affected side before each training session. The control group received sham ES. EEG, EMG and Fugl-Meyer Assessment (FMA) were collected at four different time points. The corticomuscular coherence (CMC) in the ES group at fourth weeks was significantly higher (p = 0.004) as compared to the control group. The notable increment of FMA at eight weeks and follow-up was found only in the ES group. The eight-week rehabilitation program that implemented peripheral ES sessions prior to function training has a potential to improve neuromuscular control and hand function in chronic stroke individuals.

Synchronized Astrocytic Ca2+ Responses in Neurovascular Coupling during Somatosensory Stimulation and for the Resting State

SUMMARYThe role of astrocytes in neurovascular coupling (NVC) is unclear. Here, we applied a multimodality imaging approach to concomitantly measure synchronized neuronal or astrocytic Ca2+ and hemodynamic changes in the mouse somatosensory cortex at rest and during sensory electrical stimulation. Strikingly, we found that low-frequency stimulation (0.3–1 Hz), which consistently evokes fast neuronal Ca2+ transients (6.0 ± 2.7 ms latency) that always precede vascular responses, does not always elicit astrocytic Ca2+ transients (313 ± 65 ms latency). However, the magnitude of the hemodynamic response is increased when astrocytic transients occur, suggesting a facilitatory role of astrocytes in NVC. High-frequency stimulation (5–10 Hz) consistently evokes a large, delayed astrocytic Ca2+ accumulation (3.48 ± 0.09 s latency) that is temporarily associated with vasoconstriction, suggesting a role for astrocytes in resetting NVC. At rest, neuronal, but not astrocytic, Ca2+ fluctuations correlate with hemodynamic low-frequency oscillations. Taken together, these results support a role for astrocytes in modulating, but not triggering, NVC.

Does Transcranial Direct Current Stimulation Combined with Peripheral Electrical Stimulation Have an Additive Effect in the Control of Hip Joint Osteonecrosis Pain Associated with Sickle Cell Disease? A Protocol for a One-Session Double Blind, Block-Randomized Clinical Trial.

Chronic pain in Sickle Cell Disease (SCD) is probably related to maladaptive plasticity of brain areas involved in nociceptive processing. Transcranial Direct Current Stimulation (tDCS) and Peripheral Electrical Stimulation (PES) can modulate cortical excitability and help to control chronic pain. Studies have shown that combined use of tDCS and PES has additive effects. However, to date, no study investigated additive effects of these neuromodulatory techniques on chronic pain in patients with SCD. This protocol describes a study aiming to assess whether combined use of tDCS and PES more effectively alleviate pain in patients with SCD compared to single use of each technique. The study consists of a one-session double blind, block-randomized clinical trial (NCT02813629) in which 128 participants with SCD and femoral osteonecrosis will be enrolled. Stepwise procedures will occur on two independent days. On day 1, participants will be screened for eligibility criteria. On day 2, data collection will occur in four stages: sample characterization, baseline assessment, intervention, and post-intervention assessment. These procedures will last ~5 h. Participants will be divided into two groups according to homozygous for S allele (HbSS) (n = 64) and heterozygous for S and C alleles (HbSC) (n = 64) genotypes. Participants in each group will be randomly assigned, equally, to one of the following interventions: (1) active tDCS + active PES; (2) active tDCS + sham PES; (3) sham tDCS + active PES; and (4) sham tDCS + sham PES. Active tDCS intervention will consist of 20 min 2 mA anodic stimulation over the primary motor cortex contralateral to the most painful hip. Active PES intervention will consist of 30 min sensory electrical stimulation at 100 Hz over the most painful hip. The main study outcome will be pain intensity, measured by a Visual Analogue Scale. In addition, electroencephalographic power density, cortical maps of the gluteus maximus muscle elicited by Transcranial Magnetic Stimulation (TMS), serum levels of Brain-derived Neurotrophic Factor (BDNF), and Tumor Necrosis Factor (TNF) will be assessed as secondary outcomes. Data will be analyzed using ANOVA of repeated measures, controlling for confounding variables.

Interferential current sensory stimulation, through the neck skin, improves airway defense and oral nutrition intake in patients with dysphagia: a double-blind randomized controlled trial.

BackgroundNeuromuscular electrical stimulation with muscle contraction, administered through the skin of the neck, improves a patient’s swallowing ability. However, the beneficial effects of transcutaneous electrical sensory stimulation (TESS), without muscle contraction, are controversial. We investigated the effect of TESS, using interferential current, in patients undergoing dysphagia rehabilitation.MethodsThis double-blind, randomized controlled trial involved 43 patients who were prescribed in-hospital dysphagia rehabilitation for ≥3 weeks. Patients were randomly assigned to the sensory stimulation (SS) or sham groups; all received usual rehabilitative care plus 2 weeks of SS or sham intervention. Outcome measures included cough latency times against a 1% citric acid mist, functional oral intake scale (FOIS) scores, and oral nutritional intake – each determined after the second and third week following treatment initiation.ResultsMean patient age was 84.3±7.5 years; 58% were women. The SS and sham groups had similar baseline characteristics. Changes in cough latency time at 2 weeks (−14.1±14.0 vs −5.2±14.2 s, p=0.047) and oral nutrition intake at 3 weeks (437±575 vs 138±315 kcal/day, p=0.042) improved more in the SS group than in the sham group. Changes in cough frequency and FOIS scores indicated better outcomes in the SS group, based on substantial effect sizes.ConclusionTESS, using interferential current through the neck, improved airway defense and nutrition in patients suffering from dysphagia. Further large-scale studies are needed to confirm the technique’s effect on swallowing ability.

Mapping of the brain hemodynamic responses to sensorimotor stimulation in a rodent model: A BOLD fMRI study.

Blood Oxygenation Level Dependent functional MRI (BOLD fMRI) during electrical paw stimulation has been widely used in studies aimed at the understanding of the somatosensory network in rats. However, despite the well-established anatomical connections between cortical and subcortical structures of the sensorimotor system, most of these functional studies have been concentrated on the cortical effects of sensory electrical stimulation. BOLD fMRI study of the integration of a sensorimotor input across the sensorimotor network requires an appropriate methodology to elicit functional activation in cortical and subcortical areas owing to the regional differences in both neuronal and vascular architectures between these brain regions. Here, using a combination of low level anesthesia, long pulse duration of the electrical stimulation along with improved spatial and temporal signal to noise ratios, we provide a functional description of the main cortical and subcortical structures of the sensorimotor rat brain. With this calibrated fMRI protocol, unilateral non-noxious sensorimotor electrical hindpaw stimulation resulted in robust positive activations in the contralateral sensorimotor cortex and bilaterally in the sensorimotor thalamus nuclei, whereas negative activations were observed bilaterally in the dorsolateral caudate-putamen. These results demonstrate that, once the experimental setup allowing necessary spatial and temporal signal to noise ratios is reached, hemodynamic changes related to neuronal activity, as preserved by the combination of a soft anesthesia with a soft muscle relaxation, can be measured within the sensorimotor network. Moreover, the observed responses suggest that increasing pulse duration of the electrical stimulus adds a proprioceptive component to the sensory input that activates sensorimotor network in the brain, and that these activation patterns are similar to those induced by digits paw’s movements. These findings may find application in fMRI studies of sensorimotor disorders within cortico-basal network in rodents.

SUPPRESSION OF ACTION TREMOR BY SENSORY ELECTRICAL STIMULATION IN PATIENTS WITH ESSENTIAL TREMOR

Essential tremor (ET) is the most common movement disorder that includes postural tremor and action tremor. This study investigates whether sensory electrical stimulation (SES) is effective on the action tremor in patients with ET. One task in the clinical testing of action tremor, “Archimedes spiral drawing”, was performed in 18 patients for three sessions, which were named as pre-stimulation (PRE), stimulation on (ON), and 5[Formula: see text]min after stimulation (POST). SES (sub-motor threshold) was applied on the muscles of the elbow and wrist only at ON session. Three-dimensional (3D) angular velocities were measured on three segments (index finger, hand, and forearm) from which movements of metacarpophalangeal (MP) and wrist joints were derived. Average tremor intensity in each session was represented by root mean square of the vector sum of 3D angular velocities. Tremor intensities in ON session were smaller than in PRE session in one segment (finger) and two joints (MP and wrist) ([Formula: see text]). Tremor intensities in POST session were even smaller than in ON session in all segments and one joint (wrist) ([Formula: see text]). The results indicate that SES suppresses action tremor and the effect continues and even improves 5[Formula: see text]min after the termination of stimulation. The findings of this study may contribute to the improvement of the quality of life in patients with ET.

A Comparative Study Between Two Sensory Stimulation Strategies After Two Weeks Treatment on Older Patients with Oropharyngeal Dysphagia.

Oropharyngeal dysphagia (OD) is a prevalent geriatric syndrome. Treatment is based on compensatory strategies to avoid complications. New treatments based on sensory stimulation to promote the recovery of the swallowing function have proved effective in acute studies but prolonged treatment needs further research. Our aim was to evaluate and compare the effect of two, longer-term sensory treatment strategies on older patients with OD. 38 older patients (≥70years) were studied with videofluoroscopy (pre/posttreatment) and randomized into two 10-day treatment groups: Group A-transient receptor potential vanilloid 1 (TRPV1) agonist (capsaicin 1×10(-5)M) and Group B-transcutaneous sensory electrical stimulation (TSES) (Intelect VitalStim, biphasic pulses, 300μs, 80Hz). Patients were analyzed for treatment response. Patients were old (80.47±5.2years), with comorbidities (3.11±1.59 Charlson Index), polymedication (8.92±3.31 drugs/patient), and mild functional impairment (86.84±17.84 Barthel Index), and 28.9% were at risk of malnutrition (MNA-sf). Overall, all patients had videofluoroscopic signs of impaired safety of swallow (ISS) with delayed oropharyngeal swallow response (OSR). After sensory stimulation, prevalence of ISS decreased to 68.42% in both groups (P=0.019). There were 68.42% responders in Group A (TRPV1) and 42.11% in Group B (TSES). Group A responders showed an improvement in the penetration-aspiration scale (PAS, 5.23±2.04 to 3±1.47; P=0.002), and the same was true for those of Group B (4.63±1.41 to 2.13±0.64; P=0.007). 10-day sensory stimulation with either therapy improved safety of swallow and OSR in older patients with OD, reducing the severity of OD in a significant subgroup of these patients.

Efficacy of Sensory Transcutaneous Electrical Nerve Stimulation on Perceived Pain and Gait Patterns in Individuals With Experimental Knee Pain

ObjectivesTo examine the effect of experimental knee pain on perceived knee pain and gait patterns and to examine the efficacy of transcutaneous electrical nerve stimulation (TENS) on perceived knee pain and pain-induced knee gait mechanics. DesignCrossover trial. SettingBiomechanics laboratory. ParticipantsRecreationally active, individuals without musculoskeletal pain aged 18 to 35 years (N=30). InterventionsThirty able-bodied individuals were assigned to either a TENS (n=15) or a placebo (n=15) group. All participants completed 3 experimental sessions in a counterbalanced order separated by 2 days: (1) hypertonic saline infusion (5% NaCl); (2) isotonic saline infusion (0.9% NaCl); and (3) control. Each group received sensory electrical stimulation or placebo treatment for 20 minutes, respectively. Main Outcome MeasuresPerceived pain was collected every 2 minutes using a 10-cm visual analog scale (VAS) for 50 minutes and analyzed using a mixed model analysis of covariance with repeated measures. Gait analyses were performed at baseline, infusion, and treatment. Sagittal and frontal knee angles and internal net joint torque across the entire stance were analyzed using a functional data analysis approach. ResultsHypertonic saline infusion increased perceived pain (4/10cm on a VAS; P<.05) and altered right knee angle (more flexion and less abduction; P<.05) and internal net joint torque (less extension and greater abduction; P<.05) across various stance phases. TENS treatment reduced perceived pain and improved right sagittal gait abnormalities as compared with placebo treatment (P<.05). ConclusionsThis pain model increases perceived pain and induces compensatory gait patterns in a way that indicates potential quadriceps weakness. However, TENS treatment effectively reduces perceived pain and restores pain-induced gait abnormalities in sagittal knee mechanics.

A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation.

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.