Development and feasibility assessment of a virtual reality-based aerobic exercise program with real-time pulse rate monitoring on hemodynamic and arterial stiffness in healthy people: a pilot study

Introduction

Virtual reality (VR) exercises are reportedly beneficial as a physical activity tool for health promotion and rehabilitation, and can also help individuals exercise under professional supervision. We developed and investigated the potential feasibility of a VR-based aerobic exercise program using the XBOX ONE console and Kinect sensor with real-time pulse rate monitoring. The VR setting consisted of two-dimensional (2D) environments via computer, laptop, or television screens. In addition, the study investigated the potential feasibility of the VR-based exercise program on hemodynamic response and arterial stiffness in healthy participants of various ages.

Methods

Healthy participants (n = 30) aged > 18 years were enrolled in the VR exercise-based program. All participants were required to wear a polar heart rate (HR) monitor set for moderate-intensity exercise, targeting 40%-59% of their HR reserve. Hemodynamic and arterial stiffness (pulse wave velocity) were noninvasively measured. The Borg scale rate of perceived exertion (RPE) was also assessed.

Results

Following a VR-guided exercise routine, all participants performed moderate-intensity exercise with no adverse health outcomes during or after the exercise. The effects of VR-based aerobic exercise extended beyond enhanced central hemodynamic and arterial stiffness. However, neither hemodynamic nor arterial stiffness showed significant differences before and after the VR exercise, except for a higher RPE response following the exercise program.

Conclusion

VR-based aerobic exercise with pulse rate monitoring is a promising physical activity tool to induce physiological changes and impact dyspnea scales and is also feasible for administration to healthy populations.

Effects of virtual exercise on cardio-pulmonary performance and depression in cardiac rehabilitation phase I: A randomized control trial

BACKGROUND

Cardiac rehabilitation is recommended for patients undergoing open-heart surgery (OHS). During the hospital admission, these patients suffer from reduced cardiopulmonary performance and decreased psychological health, leading to poor physical function, depression, and morbidity. To prevent post-operative pulmonary complications, a pre and post-operative physical therapy intervention is recommended for patients undergoing heart surgery. Virtual reality (VR) promotes the health status of healthy individuals and those with health conditions. However, few studies have reported the beneficial effects of VR exercise programs on the pulmonary performance and mental health status of patients undergoing OHS.

OBJECTIVES

To determine whether by using training enhanced by VR, patients who have undergone OHS can more effectively attain cardiopulmonary performance and improve depression than through conventional physical therapy.

METHOD

60 participants were randomly assigned to a conventional physical therapy and VR exercise program. Each session was conducted once daily until discharge from the hospital. Cardiorespiratory performance and depression were evaluated before surgery and at the time of discharge from the hospital. A two-way mixed ANOVA was performed to compare within (i.e., pre and post-operation) and between (i.e., VR and conventional physical therapy) groups.

RESULTS

No significant cardiopulmonary performance gains were detected in patients receiving the VR exercise program when compared with those who participated in conventional physical therapy prior to post-operative OHS (p > 0.05). However, the conventional physical therapy group showed significantly higher depression scores than the VR group (∆4.00 ± 0.98 vs. ∆1.68 ± 0.92). However, cardiopulmonary performance did not differ in both VR exercise and conventional physical therapy.

Concurrent validity and reliability of new application for 6-min walk test in healthy adults

Background

Evaluation assessments for physical performance, such as walking tests, are important for measuring a person's well-being. As of current, medical technology is primarily used to administer these assessments. However, medical devices are not easily accessible and are intended for research purposes only, and hence inconvenient for clinical use. Therefore, we aimed to develop a prototype physical performance assessor device with a mobile application and explored concurrent validity and reliability between the standard 6-min walk test (6MWT) and wearable sensor 6MWT using 6-min walk distance in healthy adults.

Methods

Sixty healthy males and females, above 18 years of age, were required to attach a sensor to their dominant ankle while the standard protocol for 6MWT was performed. After completing the walking test, the distance from the wearable sensor 6MWT with a mobile application and the standard 6MWT were recorded and compared.

Results

There was no significant difference between the distance between the standard 6MWT (410.12 ± 74.03 m) and the distance obtained with the wearable sensor. Concurrent validity was found to be moderate, and Cronbach's alpha was 0.79, which indicated good internal consistency.

Conclusion

The innovative prototype wearable walking sensor with a mobile application can effectively evaluate physical performance in healthy individuals.Clinical trial registration number: TCTR20220801002.

Technological evaluation of strategies to get out of bed by people with Parkinson's disease: Insights from multisite wearable sensors

Background

Difficulty getting out of bed is a common night-time and early morning manifestation of Parkinson's disease (PD), rated by 40% of the patients as their most concerning motor symptoms. However, current assessment methods are based on clinical interviews, video analysis, and clinical scales as objective outcome measures are not yet available.

Objective

To study the technical feasibility of multisite wearable sensors in the assessment of the supine-to-stand (STS) task as a determinant of the ability to get out of bed in patients with PD and age-matched control subjects, and develop relevant objective outcome measures.

Methods

The STS task was assessed in 32 patients with PD (mean Hoehn and Yahr; HY = 2.5) in the early morning before their first dopaminergic medication, and in 14 control subjects, using multisite wearable sensors (NIGHT-Recorder®; trunk, both wrists, and both ankles) in a sleep laboratory. Objective getting out of bed parameters included duration, onset, velocity and acceleration of truncal rotation, and angle deviation (a°) from the z-axis when subjects rose from the bed at different angles from the x-axis (10°, 15°, 30°, 45°, and 60°) as measures of truncal lateral flexion. Movement patterns were identified from the first body part or parts that moved. Correlation analysis was performed between these objective outcomes and standard clinical rating scales.

Results

Compared to control subjects, the duration of STS was significantly longer in patients with PD (p = 0.012), which is associated with a significantly slower velocity of truncal rotation (p = 0.003). Moderate and significant correlations were observed between the mean STS duration and age, and the Nocturnal Hypokinesia Questionnaire. The velocity of truncal rotation negatively and significantly correlated with HY staging. Any arm and leg moved together as the first movement significantly correlated with UPDRS-Axial and item #28. Several other correlations were also observed.

Conclusion

Our study was able to demonstrate the technical feasibility of using multisite wearable sensors to quantitatively assess early objective outcome measures of the ability of patients with PD to get out of bed, which significantly correlated with axial severity scores, suggesting that axial impairment could be a contributing factor in difficulty getting out of bed. Future studies are needed to refine these outcome measures for use in therapeutic trials related to nocturia or early morning akinesia in PD.

Non-destructive measurement technique for water content in organic solvents based on a thermal approach

The water content of organic solvents is one of the crucial properties that affect the quality of the products and the efficiency of the manufacturing processes. The established water determination methods such as Karl Fischer titration and gas chromatography require skilled operators, specific reagents, and prolonged measurement time. Thus, they are not suitable for both on-line and in-line applications. In this study, we aim to develop a real-time and low-cost device with reliable accuracy. The proposed device based on a newly developed thermal approach could non-destructively detect the water content in multiple organic solvents at low concentrations with high accuracy and without the use of any specific reagent. Experiments were performed for the determination of water content in organic solvents such as methanol, ethanol, and isopropanol. The results show that the proposed device is feasible for the water content determination in methanol, ethanol, and isopropanol at 0–1% w/w. A Bland–Altman plot to illustrate the differences in measurements between the proposed device and coulometric Karl Fischer titration shows that most of the measurements lie within the limits of agreement where 95% of the differences between the two methods are expected to fall in the range of −0.13% and 0.09%.

The proposed device could non-destructively detect the water content in organic solvents at low concentrations with high accuracy and without any specific reagent. It could determine the water content in methanol, ethanol, and isopropanol at 0–1% w/w.

Classification of 41 Hand and Wrist Movements via Surface Electromyogram Using Deep Neural Network

Surface electromyography (sEMG) is a non-invasive and straightforward way to allow the user to actively control the prosthesis. However, results reported by previous studies on using sEMG for hand and wrist movement classification vary by a large margin, due to several factors including but not limited to the number of classes and the acquisition protocol. The objective of this paper is to investigate the deep neural network approach on the classification of 41 hand and wrist movements based on the sEMG signal. The proposed models were trained and evaluated using the publicly available database from the Ninapro project, one of the largest public sEMG databases for advanced hand myoelectric prosthetics. Two datasets, DB5 with a low-cost 16 channels and 200 Hz sampling rate setup and DB7 with 12 channels and 2 kHz sampling rate setup, were used for this study. Our approach achieved an overall accuracy of 93.87 ± 1.49 and 91.69 ± 4.68% with a balanced accuracy of 84.00 ± 3.40 and 84.66 ± 4.78% for DB5 and DB7, respectively. We also observed a performance gain when considering only a subset of the movements, namely the six main hand movements based on six prehensile patterns from the Southampton Hand Assessment Procedure (SHAP), a clinically validated hand functional assessment protocol. Classification on only the SHAP movements in DB5 attained an overall accuracy of 98.82 ± 0.58% with a balanced accuracy of 94.48 ± 2.55%. With the same set of movements, our model also achieved an overall accuracy of 99.00% with a balanced accuracy of 91.27% on data from one of the amputee participants in DB7. These results suggest that with more data on the amputee subjects, our proposal could be a promising approach for controlling versatile prosthetic hands with a wide range of predefined hand and wrist movements.

Development and validation of point-of-care testing of albuminuria for early screening of chronic kidney disease

INTRODUCTION

Chronic kidney disease (CKD) is a significant global health issue. As the prevalence of renal replacement therapy (RRT) in Thailand is increasing, early detection and management of CKD is the most important step to prevent CKD progression and the need for RRT. Current diagnostic tests for CKD are non-specific and expensive. We aimed to develop and validate antibody-based-albumin point-of-care testing (POCT) to detect patients with impaired kidney function at early stage.

METHODS

The prototype strip test was developed under the concept of competitive lateral flow immunochromatography assay, or strip test. Monoclonal antibodies (MAbs) to human serum albumin (HSA) were harvested from the hybridomas of spleen cells from immunized mice and mouse myeloma cells. Presence of MAbs was detected by enzyme-linked immunosorbent assay (ELISA). Spot urine was obtained from patients with kidney disease, type I, or type II Diabetes Mellitus upon their visit at King Chulalongkorn Memorial Hospital during 2018-2019. All samples were analyzed for urine albumin with our POCT (CU microalbumin) and the other two commercial POCTs (Microalbu PHAN and MICRAL). The results were validated against standard method for urine microalbumin measurement. A urine microalbumin concentration of less than 20 ug/ml was defined as normal. The sensitivity, specificity, and predictive values were calculated in comparison with the standard laboratory method.

RESULT

A total of 100 adult patients were included. CU microalbumin had a sensitivity of 86%, a specificity of 94%, and a positive predictive value of 96%. Our POCT showed good correlation with the laboratory results.

CONCLUSION

CU microalbumin correlated well with the standard method for quantitative measurement of urine albumin. Therefore, it has the potential for early screening of CKD, especially in primary health care facilities in resource limited settings.

Development and application of a respiratory device on blood pressure in adults with high blood pressure

Purpose

The purpose of this study is to develop a prototype of a novel respiratory device that we validated and assessed clinically and examined the effect of prototype of respiratory device on blood pressure (BP).

Methods

Prototype of respiratory device (TU-Breath Training) was designed with pressure cuff and application software was created. The immediate effect of resisted breathing was determined in 20 adults with high BP (systolic BP ≥ 130 mmHg and diastolic BP ≥ 90 mmHg). A crossover study was designed. A total of 20 eligible participants were asked to sit quietly for 10 min. Heart rate (HR), BP, and oxygen saturation (SpO₂) were measured and recorded. After the resting period, all participants were randomized and counterbalanced for undergoing the set of inspiratory muscle training by TU-Breath Training and control group. A set of respiratory training were composed of 10 times per set for three sets, while the control group was asked to sit for 10 min.

Results

After inspiratory training, both the systolic and diastolic BP decreased significantly. Compared with control group, using TU-Breath Training decreased systolic BP (−7.00 ± 5.93 mmHg) and diastolic BP (−5.95 ± 8.88 mmHg), but did not show differences in HR and SpO₂.

Conclusion

The study indicated that in high-BP participants, the prototype of respiratory device (TU-Breath Training) elicits decreased BP.

The Ambulatory Eye Shield Head Tracking Device with Real-Time Feedback for Gas Filled Eye Patients

Gas filled eye surgery is a part of treatment for vitreoretinal diseases such as retinal detachment and macular hole surgery. The patient compliance to maintain the correct position after treatment with gas filling procedure is one of key factor for successful of surgery treatment which helps to restore the vision. The objective of this study is to describe an innovation of eye shield that may improve the positioning compliance for gas filled eye patient and to demonstrate its reliability.The experiment was designed to assess the agreement of the different angles compared to a commercial inclinometer. The angulation was evaluated at 0°, 15°, 30°. 45°, 60°, 75°, 90°, 105°, 120°, 135°, 150°, 165° and 180°. The data analysis shows that the proposed devices have the same measurement as the standard measurement with an Intraclass correlation of >0.99.

Non-invasive textile based colorimetric sensor for the simultaneous detection of sweat pH and lactate

A non-invasive textile-based colorimetric sensor for the simultaneous detection of sweat pH and lactate was created by depositing of three different layers onto a cotton fabric: 1.) chitosan, 2.) sodium carboxymethyl cellulose, and 3.) indicator dye or lactate assay. This sensor was characterized using field emission scanning electron microscopy and fourier transform infrared spectroscopy. Then, this sensor was used to measure pH and lactate concentration using the same sweat sample. The sensing element for sweat pH was composed of a mixture of methyl orange and bromocresol green while a lactate enzymatic assay was chosen for the lactate sensor. The pH indicator gradually shifted from red to blue as the pH increased, whereas the purple color intensity increased with the concentration of lactate in the sweat. By comparing these colors with a standard calibration, this platform can be used to estimate the sweat pH (1-14) and the lactate level (0-25 mM). Fading of the colors of this sensor was prevented by using cetyltrimethylammonium bromide (CTAB). The flexibility of this textile based sensor allows it to be incorporated into sport apparels and accessories hence potentially enabling real-time and continuous monitoring of sweat pH and lactate. This non-invasive sensing platform might open a new avenue for personal health monitoring and medical diagnosis as well as for determining of the physiological conditions of endurance athletes.

Capturing nighttime symptoms in Parkinson disease: Technical development and experimental verification of inertial sensors for nocturnal hypokinesia

Although nocturnal hypokinesia represents one of the most common nocturnal disabilities in Parkinson disease (PD), it is often a neglected problem in daily clinical practice. We have developed a portable ambulatory motion recorder (the NIGHT-Recorder), which consists of 16-bit triaxial integrated microelectromechanical system inertial sensors that are specifically designed to measure movements, register the position of the body with respect to gravity, and provide information on rotations on the longitudinal axis while lying in bed. The signal processing uses the forward derivative method to identify rolling over and getting out of bed as primary indicators. The prototype was tested on six PD pairs to measure their movements for one night. Using predetermined definitions, 134 movements were captured consisting of rolling over 115 times and getting out of bed 19 times. Patients with PD rolled over significantly fewer times than their spouses (p = 0.03), and the position change was significantly smaller in patients with PD (p = 0.03). Patients with PD rolled over at a significantly slower speed (p = 0.03) and acceleration (p = 0.03) than their spouses. In contrast, patients with PD got out of bed significantly more often than their spouses (p = 0.02). It is technically feasible to develop an easy-to-use, portable, and accurate device that can assist physicians in the assessment of nocturnal movements of patients with PD.

Tremor's glove-an innovative electrical muscle stimulation therapy for intractable tremor in Parkinson's disease: A randomized sham-controlled trial

BACKGROUND

Medically refractory resting tremor is a debilitating symptom of Parkinson's disease (PD) patients. In our pilot study, modulation of peripheral reflex mechanism by electrical muscle stimulation (EMS) temporarily suppressed tremor.

OBJECTIVES

To investigate the efficacy of EMS, delivered using Tremor's glove, as a treatment of resting hand tremor.

PATIENTS AND METHODS

Thirty PD patients with medically refractory resting tremor were randomly allocated to a Tremor's glove group (n=15) or a sham glove group (n=15). Gloves were placed on the most tremulous hand for 30min per testing session. Demographics, clinical rating scales, and tremor parameters (RMS of angular velocity and angular displacement, peak magnitude, and frequency) were assessed before and during stimulation. Correlations with validated clinical rating scales were performed.

RESULTS

There were no statistically significant differences between groups in demographics, rating scales, or tremor parameters. During stimulation, significant reduction in RMS angular velocity (as percentage) in every axis and peak magnitude in axis (x-, y-) and UPDRS tremor score, were found with Tremor's glove compared to the sham groups (p<0.05, each). Significant moderate correlations were observed between a percentage reduction of RMS angular velocity in every axis and UPDRS tremor scores. Mean duration of tremor reduction after stimulation was 107.78±104.15s. No serious adverse events were observed.

CONCLUSION

In this study, EMS-based Tremor's glove was effective in suppressing resting hand tremor in PD patients. Tremor's glove is light-weight with a good safety profile, making it a future potential therapeutic option for PD patients with medically refractory tremor.

Rotigotine for nocturnal hypokinesia in Parkinson's disease: Quantitative analysis of efficacy from a randomized, placebo-controlled trial using an axial inertial sensor

BACKGROUND

Nocturnal hypokinesia is a common symptom in Parkinson's disease (PD), negatively affecting quality of life of both patients and caregivers. However, evidence-based treatment strategies are limited.

OBJECTIVE

To evaluate the efficacy of rotigotine transdermal patch, using a wearable sensor, in the management of nocturnal immobility.

METHODS

34 PD subjects with nocturnal immobility were randomized to receive rotigotine transdermal patch (mean ± SD of 10.46 ± 4.63 mg/24 h, n = 17) or placebo patch (n = 17). Treatment was titrated to an optimal dose over 1-8 weeks, then maintained for 4 weeks. Primary endpoints were objective parameters assessing axial rotation measured using an axial inertial sensor (the NIGHT-Recorder) over two nights at the patients' home. Scale-based assessments were also performed.

RESULTS

There was a significant difference, in favor of rotigotine, in change from baseline score in the number of turns in bed (ANCOVA, p = 0.001), and degree of axial turn (p = 0.042). These objective improvements were mirrored by significantly greater improvements in clinical scale-based assessments, including the Unified Parkinson's Disease Rating Scale (UPDRS) total scores (p = 0.009), UPDRS-motor scores (p < 0.001), UPDRS-axial scores (p = 0.01), the Modified Parkinson's Disease Sleep Scale (p < 0.001), the Nocturnal Akinesia Dystonia and Cramp Scale (p = 0.003) and the eight-item PD Questionnaire (PDQ-8) scores (p = 0.01) from baseline to end of treatment in patients given rotigotine compared to placebo.

CONCLUSION

We show that the rotigotine patch provides a significant improvement in nocturnal symptoms as assessed using both objective measures and clinical rating scales. The study demonstrates the feasibility of using wearable sensors to record objective outcomes in PD-related clinical trials.

Impaired bed mobility: quantitative torque analysis with axial inertial sensors

Difficulty in turning in bed is rated as the most troublesome night-time symptom among Parkinson’s disease (PD) patients. Aim: To develop a practical objective method for home assessment of a patient’s ability to turn in bed. Methods: Nocturnal parameters and torque of self-turning in bed from 17 PD couples were assessed and compared using a wearable axial sensor for two nights in their homes. Results: The torque of axial rotation which indicates the ability of PD patients to turn in bed was significantly less than their spouses (p < 0.001). Significant correlations were observed between the torque of turning in bed and total unified Parkinson’s Disease Rating Scale score (r = 0.71; p = 0.001), and total Nocturnal Akinesia Dystonia and Cramp score (r = 0.634; p = 0.006). Conclusion: Our study confirms a decreased ability in turning in PD.

Support vector machine classification of Parkinson's disease and essential tremor subjects based on temporal fluctuation

Tremor is a common symptom shared in both Parkinson's disease (PD) and Essential tremor (ET) subjects. The differential diagnosis of PD and ET tremor is important since the realization of treatment depends on specific medication. A novel feature is developed based on a hypothesis that tremor of PD subject has a larger fluctuation during resting than action task. Tremor signal is collected using a triaxial gyroscope sensor attached to subject's finger during kinetic and resting task. The angular velocity signal is analyzed by transforming a one-dimensional to two-dimensional signal using a relation of signal and its delay versions. Tremor fluctuation is defined as the area of 95% confidence ellipse covering the two-dimensional signal. The tremor fluctuation during kinetic and resting task is used as classification features. The support vector machine is used as a classifier and tested with 10-fold cross-validation. This novel feature provides a perfect PD/ET classification with 100% accuracy, sensitivity and specificity.

Quantitative demonstration of the efficacy of night-time apomorphine infusion to treat nocturnal hypokinesia in Parkinson's disease using wearable sensors

BACKGROUND

Nocturnal hypokinesia/akinesia is one of the common night-time symptoms in patients with Parkinson's disease (PD), negatively affecting quality of life of patients and caregivers. The recognition of this problem and treatment options are limited in clinical practice.

OBJECTIVES

To evaluate the efficacy of nocturnal apomorphine infusion, using a wearable sensor, in patients who are already on daytime continuous subcutaneous apomorphine infusion and still suffer from nocturnal hypokinesia.

METHODS

Nocturnal parameters in 10 PD patients before and during nocturnal infusion were assessed over two nights at their homes, using a wearable sensor (trunk). Nocturnal parameters included number, velocity, acceleration, degree, and duration of rolling over, and number of times they got out of bed. Correlations with validated clinical rating scales were performed.

RESULTS

Following nocturnal apomorphine infusion (34.8 ± 6.5 mg per night), there were significant improvements in the number of turns in bed (p = 0.027), turning velocity (p = 0.046), and the degree of turning (p = 0.028) in PD patients. Significant improvements of Modified Parkinson's Disease Sleep Scale (p = 0.005), the axial score of Unified Parkinson's Disease Rating Scale (p = 0.013), and Nocturnal Akinesia Dystonia and Cramp Scale (p = 0.014) were also observed.

CONCLUSION

Our study was able to demonstrate quantitatively the efficacy of nocturnal apomorphine infusion in PD patients with nocturnal hypokinesia and demonstrated the feasibility of using wearable sensors to yield objective and quantifiable outcomes in a clinical trial setting. More studies are needed to determine the long-term efficacy of this treatment in a large prospective cohort of PD patients.

Temporal fluctuations of tremor signals from inertial sensor: a preliminary study in differentiating Parkinson's disease from essential tremor

BACKGROUND

Parkinson's disease (PD) and essential tremor (ET) are the two most common movement disorders but the rate of misdiagnosis rate in these disorders is high due to similar characteristics of tremor. The purpose of the study is to present: (a) a solution to identify PD and ET patients by using the novel measurement of tremor signal variations while performing the resting task, (b) the improvement of the differentiation of PD from ET patients can be obtained by using the ratio of the novel measurement while performing two specific tasks.

METHODS

35 PD and 22 ET patients were asked to participate in the study. They were asked to wear a 6-axis inertial sensor on his/her index finger of the tremor dominant hand and perform three tasks including kinetic, postural and resting tasks. Each task required 10 s to complete. The angular rate signal measured during the performance of these tasks was band-pass filtered and transformed into a two-dimensional representation. The ratio of the ellipse area covering 95 % of this two-dimensional representation of different tasks was investigated and the two best tasks were selected for the purpose of differentiation.

RESULTS

The ellipse area of two-dimensional representation of the resting task of PD and ET subjects are statistically significantly different (p < 0.05). Furthermore, the fluctuation ratio, defined as a ratio of the ellipse area of two-dimensional representation of resting to kinetic tremor, of PD subjects were statistically significantly higher than ET subjects in all axes (p = 0.0014, 0.0011 and 0.0001 for x, y and z-axis, respectively). The validation shows that the proposed method provides 100 % sensitivity, specificity and accuracy of the discrimination in the 5 subjects in the validation group. While the method would have to be validated with a larger number of subjects, these preliminary results show the feasibility of the approach.

CONCLUSIONS

This study provides the novel measurement of tremor variation in time domain termed 'temporal fluctuation'. The temporal fluctuation of the resting task can be used to discriminate PD from ET subjects. The ratio of the temporal fluctuation of the resting task to the kinetic task improves the reliability of the discrimination. While the method is powerful, it is also simple so it could be applied on low resource platforms such as smart phones and watches which are commonly equipped with inertial sensors.

Exploring the effect of electrical muscle stimulation as a novel treatment of intractable tremor in Parkinson's disease

BACKGROUND

As the pathophysiology of tremor in Parkinson disease (PD) involves a complex interaction between central and peripheral mechanisms, we propose that modulation of peripheral reflex mechanism by electrical muscle stimulation (EMS) may improve tremor temporarily.

OBJECTIVES

To determine the efficacy of EMS as a treatment for drug resistant tremor in PD patients.

METHODS

This study was a single-blinded, quasi-experimental study involving 34 PD patients with classic resting tremor as confirmed by tremor analysis. The EMS was given at 50Hz over the abductor pollicis brevis and interrosseus muscles for 10s with identified tremor parameters before and during stimulation as primary outcomes.

RESULTS

Compared to before stimulation, we observed a significant reduction in the root mean square (RMS) of the angular velocity (p<0.001) and peak magnitude (p<0.001) of resting tremor while tremor frequency (p=0.126) and dispersion (p=0.284) remained unchanged during stimulation. The UPDRS tremor score decreased from 10.59 (SD=1.74) before stimulation to 8.85 (SD=2.19) during stimulation (p<0.001). The average percentage of improvement of the peak magnitude and RMS angular velocity was 49.57% (SD=38.89) and 43.81% (SD=33.15) respectively. 70.6% and 61.8% of patients experienced at least 30% tremor attenuation as calculated from the peak magnitude and RMS angular velocity respectively.

CONCLUSIONS

Our study demonstrated the efficacy of EMS in temporarily improving resting tremor in medically intractable PD patients. Although tremor severity decreased, they were not completely eliminated and continued with a similar frequency, thus demonstrating the role of peripheral reflex mechanism in the modulation of tremor, but not as a generator. EMS should be further explored as a possible therapeutic intervention for tremor in PD.

Temporal fluctuation analysis of tremor signal in Parkinson's disease and Essential tremor subjects

Tremor is a common symptom shared in both Parkinson's disease (PD) and Essential tremor (ET) subjects. The differential diagnosis of PD and ET tremor is important since the treatment depends on specific medication. A novel feature was developed based on a hypothesis stating that the tremor of PD subject has a larger fluctuation while performing resting task than action task. Tremor signal was collected using a gyroscope sensor attached to subject's finger. The angular velocity signal was analyzed by transforming a one-dimensional to two-dimensional signal based on relation of different units of time-delay. The tremor fluctuation was defined as the area of 95% confidence ellipse covering the two-dimensional signal. Experimenting with 32 PD and 20 ET subjects, a ratio of fluctuation of resting to kinetic task can be a sensitive feature to discriminate PD from ET with 100% accuracy.

Alteration of the end-plane angle in press-fit cylindrical stem radial head prosthesis: an in vitro study

PURPOSE

Many studies comparing the morphology of native radial head with the prosthesis have been published. However, there is limited information regarding the postoperative alignment of the articular surface following the radial head replacement. The purpose of this study is to evaluate the alteration of the end-plane angle in the modular radial head prosthesis with a press-fit cementless cylindrical stem.

METHODS

The study used 36 cadaveric radii. The press-fit size prosthesis with cylindrical stem was inserted into each specimen. The end-plane angles of the radial head before and after prosthetic replacement, were measured in coronal and sagittal planes with a digital inclinometer. The data were analyzed by paired t-test.

RESULTS

From paired t-test, there were statistically symmetrical end-plane angles before and after radial head replacement in both coronal and sagittal planes (p-value < 0.01). The mean of radial head end-plane angle alteration in the coronal plane was 3.62° (SD, 2.76°) (range, 0.3°-8.9°). In the sagittal plane, the mean of alteration was 5.85° (SD, 3.56°) degrees (range, 0.3° - 14.2°).

CONCLUSION

The modular radial head prosthesis with cylindrical stem is in vitro able to restore the native end-plane angles of radial heads statistically when used in a press-fit fashion.