Changes In Arm Position Research Articles

Reducing Motor Variability Enhances Myoelectric Control Robustness Across Untrained Limb Positions

Reducing Motor Variability Enhances Myoelectric Control Robustness Across Untrained Limb Positions

Laser flowmetry of microcirculation of the finger depending on the external temperature and the limb position

Introduction. The use of laser Doppler flowmetry (LDF) makes it possible to assess the condition and disorders of blood microcirculation, improving the quality of diagnosis of various cardiovascular diseases. Additional functional tests with laser flowmetric measurements are used to assess the state of the mechanisms that regulate the tissue blood flow. Objective. To identify patterns of blood flow changes in the microcirculatory bed when combining a postural test and a change in air temperature. Materials and methods. The study was conducted on a group of 20 subjects, which included an equal number of girls and boys aged 21–23 years, who were considered healthy and did not have cardiovascular diseases. The experiment was carried out in two stages: first in a room with an air temperature of 201 °C, then at 301 °C. To assess the difference in data between arm positions within the same study phase at the same temperature, the Student’s t-test was used to compare quantitative variables in two dependent samples. The Wilcoxon test was used to assess statistical differences in data for the same hand position but at different air temperatures. Changes were considered statistically significant at p<0.05. The subjects were measured the microcirculation of peripheral blood vessels on the phalanx of the finger in three positions relative to the level of the heart using a portable laser Doppler flowmeter LAZMA PF (Russia). Results. It is shown that an increase in ambient temperature leads to an increase in the difference in microcirculation of peripheral vessels when the arm position changes relative to the level of the heart. When a person is in a room with a temperature of 301 °C, dilation of blood vessels and changes in their tone occur, which explains the increase in microcirculation values in relative perfusion units. Conclusions. The results of the study showed an increase in statistically significant differences according to the Student’s t-test between the different hand positions with increasing room temperature (p<0.0001). In a comparative sample between the first stage (at an air temperature of 20±1 °C) and the second stage of the study (at an air temperature of 30±1 °C), statistically significant results (p<0.001) were obtained according to the Wilcoxon test for the hand position at the heart level and the raised arm.

Improving the Robustness of Human-Machine Interactive Control for Myoelectric Prosthetic Hand During Arm Position Changing.

Robust classification of natural hand grasp type based on electromyography (EMG) still has some shortcomings in the practical prosthetic hand control, owing to the influence of dynamic arm position changing during hand actions. This study provided a framework for robust hand grasp type classification during dynamic arm position changes, improving both the “hardware” and “algorithm” components. In the hardware aspect, co-located synchronous EMG and force myography (FMG) signals are adopted as the multi-modal strategy. In the algorithm aspect, a sequential decision algorithm is proposed by combining the RNN-based deep learning model with a knowledge-based post-processing model. Experimental results showed that the classification accuracy of multi-modal EMG-FMG signals was increased by more than 10% compared with the EMG-only signal. Moreover, the classification accuracy of the proposed sequential decision algorithm improved the accuracy by more than 4% compared with other baseline models when using both EMG and FMG signals.

Two-stage classification of electromyogram signals from hand grasps in the transverse plane

This paper presents a two-stage classification to resolve the effect of arm position changes on electromyogram (EMG) classification for hand grasps in the transverse plane. The proposed method combines the EMG signals with the signals from an inertial measurement unit in both the position and motion classification stages. To improve accuracy, we incorporate EMG data from the upper arm and shoulder with the forearm EMG signals. When evaluated on the five alternative object grasps placed on the nine positions, the proposed technique yields an average total classification error of 0.9%, which is a substantial improvement over the single-stage classification (4.3%).

Effect of Upper Arm Position Changes on the Occurrence of Ipsilateral Shoulder Pain After Single-Operator Port Thoracoscopy

BackgroundThe aim of this study was to explore the factors associated with the occurrence of ISP after VATS to reduce the incidence of ISP and improve patients' quality of life.MethodsThe data of patients were collected between June 2020 and August 2020 in the Department of Lung Cancer Surgery, Tianjin Medical University General Hospital. The angle of upper arm was measured intraoperatively. The patient's postoperative shoulder function was quantified using the Constant-Murley shoulder function rating score. The proportional hazards model was applied to identify multiple influence factors.ResultsA total of 140 eligible patients met criteria. At postoperative day 3, only the age influenced patients' shoulder pain. At postoperative day 14, univariate and multivariate logistic regression analyses showed that age (odds ratio [OR]: 1.098 [1.046-1.152]; P < 0.001) and upper arm Angle A (OR: 1.064 [1.011-1.121]; P = 0.018) were independent risk factors for low shoulder function scores. However, height was its protective factor (OR: 0.923 [0.871-0.977]; P = 0.006). At postoperative day 42, univariate and multivariate logistic regression analyses showed that age (OR: 1.079 [1.036-1.124]; P < 0.001) was a risk factor for low shoulder function scores, and height (OR: 0.933 [0.886-0.983]; P = 0.009) was its protective factor. In contrast, upper arm Angle B was not statistically associated with low shoulder function scores (P>0.05). In addition, the reduction in ipsilateral Shoulder scores after surgery was higher in patients with more than 113° of angle A (P = 0.025).ConclusionISP was closely related to the angle of anterior flexion of the upper arm on the patient's operative side intraoperatively. The increase in the degree of postoperative shoulder injury is more pronounced for an anterior flexion angle of >113°. Therefore, we recommend that the angle of anterior flexion of the upper extremity should be <113° intraoperatively.

Activities of Daily Living-Based Rehabilitation System for Arm and Hand Motor Function Retraining After Stroke.

Most stroke survivors have difficulties completing activities of daily living (ADLs) independently. However, few rehabilitation systems have focused on ADLs-related training for gross and fine motor function together. We propose an ADLs-based serious game rehabilitation system for the training of motor function and coordination of both arm and hand movement where the user performs corresponding ADLs movements to interact with the target in the serious game. A multi-sensor fusion model based on electromyographic (EMG), force myographic (FMG), and inertial sensing was developed to estimate users' natural upper limb movement. Eight healthy subjects and three stroke patients were recruited in an experiment to validate the system's effectiveness. The performance of different sensor and classifier configurations on hand gesture classification against the arm position variations were analyzed, and qualitative patient questionnaires were conducted. Results showed that elbow extension/flexion has a more significant negative influence on EMG-based, FMG-based, and EMG+FMG-based hand gesture recognition than shoulder abduction/adduction does. In addition, there was no significant difference in the negative influence of shoulder abduction/adduction and shoulder flexion/extension on hand gesture recognition. However, there was a significant interaction between sensor configurations and algorithm configurations in both offline and real-time recognition accuracy. The EMG+FMG-combined multi-position classifier model had the best performance against arm position change. In addition, all the stroke patients reported their ADLs-related ability could be restored by using the system. These results demonstrate that the multi-sensor fusion model could estimate hand gestures and gross movement accurately, and the proposed training system has the potential to improve patients' ability to perform ADLs.

RANCANG BANGUN MODUL 3 PRAKTIKUM SISTEM EMBEDDED BERBASIS RASPBERRY PI (PERCOBAAN 3: PENGONTROLAN LAMPU MELALUI APLIKASI ANDROID)

The role of university in supporting embedded system development and Internet Of Thingsimplementation seen with Embedded System + Lab Course in Electrical Engineering StudyPorgram, Engineering Faculty, Udayana University. Embedded System + Lab Course is a newcourse, so it’s not available yet learning tools in the terms of supporting the course, then it isnecessary to create Embedded System Practicum Module. Embedded System PracticumModule cosists of 4 kinds of experiment. 1st experiment: monitoring servo motor arm positionchange with PIR sensor in Android application. 2nd experiment: monitoring servo motor armposition change with ultrasonic sensor in Android application. 3rd experiment: controlling andmonitoring light bulb with Android application. 4th experiment: controlling and monitoring lightbulb with Telegram Bot. Given the many results of the discussion of experiments and subexperimentsin module 3, in this article, only experimental data 3 data will be discussed.Experimental data in 3rd module showing the success of tool performance and output datasuitability of monitoring and controlling lamp load status on Python Shell, Firebase and Androidapplication. Can be concluded in this research that the success of making 3rd ModuleEmbedded System Practicum(3rd Experiment : Lamp Controlling Through Android Application)has worked well. The overall experimental data can show the success of parsing JSON data onthe Python Shell platform, Firebase database, Android application.

Effect of static body and arm position on blood pressure in young healthy college students

While interarm blood pressure differences have been regularly reported in older, diseased populations, it is not entirely known whether interarm BP differences exist in young, healthy populations. It is also well established that body and arm position influence BP measurements, but it isn't fully clear whether this observation holds true for both arms. The purpose of this study was to examine whether interarm BP differences exist in different static body and arm positions in young, healthy subjects. It was hypothesized that no interarm BP differences would be observed, independent of body and arm position. Young (20.4y/o; SD=1.20), college student subjects (n=18; 9 males; 9 females) had BP taken from both arms while standing, sitting, and supine, with arm parallel and perpendicular to the body. Respiratory rate was locked at 15-20bpm for each subject, and BPs were obtained 1 minute after the change in body or arm position. Subject mean body mass index was 27.5kg/m2 (SD=5.74) and all subjects were college athletes. No within arm differences in BP were observed for the right or left arm, independent of body and arm position. The left arm tended to have higher mean systolic BP when parallel (stand 149.2mmHg, SD=22.2; sit 140.5mmHg, SD=20.8; supine 134.6mmH, SD=19.1) or perpendicular (stand 129.5mmHg, SD=20.7; sit 124.2mmHg, SD=18.0) compared to the right arm mean systolic BP when parallel (stand 125.3mmHg, SD=12.6; sit 124.6mmHg, SD=9.8; supine 121.2mmHg, SD=10.7) or perpendicular (stand 113.6mmHg, SD=13.1; sit 110.3mmHg, SD=11.2). The left arm also tended to have higher mean diastolic BP when parallel (stand 88.2mmHg, SD=14.4; sit 79.4mmHg, SD=13.4; supine 74.1mmHg, SD=10.2) or perpendicular (stand 68.1mmHg, SD=11.6; sit 64.1mmHg, SD=11.3) compared to the right arm mean diastolic BP when parallel (stand 75.6mmHg, SD=8.3; sit 74.0mmHg, SD=8.8; supine 66.8mmHg, SD=8.8) or perpendicular (stand 64.8mmHg, SD=9.6; sit 60.1mmHg, SD=9.4). However, no statistically significant interarm BP differences were observed, independent of arm or body position. Heart rate tended to decline as subjects moved from standing (86.7bpm, SD=12.8) to sitting (75.9bpm, SD=10.3) to supine (66.4bpm, SD=7.6), but this was not statistically significant. The results of this study should be taken into consideration when obtaining BPs from young, healthy people. This is particularly important given the regular reporting of interarm BP differences in older, diseased populations. Future studies should examine whether interarm BP differences exist in older, diseased populations in different body and arm positions.

Enhanced myoelectric control against arm position change with weighted recursive Gaussian process

In the last decade, there has been huge advancement in biomechatronic systems by the integration of pattern recognition and regression algorithms. In many myoelectric control studies, high accuracy in estimating a subject’s wrist movement was reported by measuring electromyography (EMG) signal from subjects’ forearms. However, many algorithms suffer from limited robustness against undesired disturbance in the real-world environment. In particular, arm position change is an inevitable disturbance that results in severe degradation of performance. In this study, the weighted recursive Gaussian process (WRGP) is proposed to overcome this effect. In the algorithm, the noise variance is weighted by covariate shift adaptation, which is able to handle the uncertainties. WRGP is compared with the commonly used linear regression (LR) and multilayer perceptron (MLP). LR, MLP, and WRGP are trained with the EMG dataset acquired at an arm position and tested with the different EMG dataset acquired at another arm position. Also, WRGP with uniform weights and WRGP with the weights estimated from the covariate shift adaptation are compared. The results show that WRGP with uniform weights is more robust than LR and MLP regardless of the arm position (0.16 and 0.16 higher average $$R^2$$ index, respectively). The performance of WRGP with the weights estimated from the covariate shift adaptation is significantly higher ( $$p<0.05$$ ) than the performance of LR and MLP (0.30 and 0.33 higher average $$R^2$$ index, respectively).

Limb Position Change Affects Tourniquet Pressure.

Limb position changes are likely during transport from injury location to definitive care. This study investigated passive limb position change effects on tourniquet pressure and occlusion. Triplicate buddy-applied OMNA® Marine Tourniquet applications to Doppler-based occlusion were done to sitting and laying supine mid-thigh (n=5) and sitting mid-arm (n=3). Tourniqueted limb positions were bent/straight/bent and straight/bent/straight (randomized first position order, 5 seconds/position, pressure every 0.1 second, two-way repeated measures ANOVA). Sitting thigh occlusion pressures leg bent were higher than straight (median, minimum-maximum; 328, 307-403mmHg versus 312, 295-387mmHg, p = .013). In each recipient, the pressure change for each position change for each limb had p < .003. In each recipient, when sitting, leg bent to straight increased pressure (326, 276-415mmHg to 371, 308-427mmHg bent first and 275, 233-354mmHg to 311, 241-353mmHg straight first), and straight to bent decreased pressure (371, 308-427mmHg to 301, 262-388mmHg bent first and 312, 265-395mmHg to 275, 233-354mmHg straight first). When laying, position changes from leg bent first resulted in pressure changes in each recipient but not in the same directions in each recipient. From laying leg straight first, in each recipient changing to bent increased the pressure (295, 210-366mmHg to 328, 255-376mmHg) and to straight decreased the pressure (328, 255-376 mmHg to 259, 210-333 mmHg). Sitting arm bent occlusion pressures were lower than straight (230, 228-252mmHg versus 256, 250-287mmHg, p = .026). Arm position changes resulted in pressure changes in each recipient but not in the same directions in each recipient. Changes in pressure trace character (presence or absence of rhythmically pulsatile traces) and Doppler-based occlusion were consistent with limb position-induced changes in tourniquet pressure (each p ≤ .001 leg, p = .071 arm traces, and p = .188 arm occlusion). Passive limb position changes can cause significant changes in tourniquet pressure. Therefore, tourniquet adequacy should be reassessed after any limb position change.

Biomechanical and Clinical Evaluation of the Optimal Arm Position After Rotator Cuff Surgery With an Adjustable Abduction Brace.

Abduction braces are used with the intention of relieving tension on the supraspinatus, thereby protecting an operative repair. It is not known, however, whether patients wearing a brace do deposit the weight of the arm on the brace effectively or actively stabilize the arm despite the brace. It is further unknown what position of the arm is most effective to relax the shoulder and is considered most comfortable. Twenty-two patients who had undergone an arthroscopic supraspinatus repair were postoperatively fitted with a standard abduction brace equipped with a torque sensor to measure the weight of the arm on the brace on the first and second postoperative days. The most comfortable arm position, tear size, and degenerative muscular changes on magnetic resonance imaging were assessed. Most patients (15 vs 5) preferred a low angle of abduction with the brace in the scapular rather than the true frontal plane irrespective of tear location or size. While loads applied to the brace were slightly higher at high abduction angles (70° and 90°) under regional anesthesia (day 1), they were significantly higher at low abduction angles (30° and 50°) with the arm fully awake (day 2). The most comfortable brace position-which is at low angles of abduction (30° to 50°) in the scapular plane-is associated with the highest load transfer to the brace in the unanesthetized arm. The authors therefore conclude that if an abduction brace is used, it should be fitted in the scapular plane with an abduction angle between 30° and 50°. [Orthopedics. 2021;44(1):e1-e6.].

Influence of arm position change from adduction to abduction on intracavitary electrocardiogram

The aim of this study is to evaluate the influence of arm movements from adduction to abduction on intracavitary electrocardiogram and the position of a catheter tip. Overall, 192 peripherally inserted central catheter lines were placed under intracavitary electrocardiogram guidance and 188 of them were enrolled in the study. The catheter was first placed at a time point corresponding to the peak P wave with the arm in adduction. The arm was then abducted to 90° without changing catheter insertion length. During the procedure, basal electrocardiogram, intracavitary electrocardiogram, and radiographs with the arm in adduction and abduction were recorded. Amplitude wave changes and catheter movements were measured on electrocardiogram records and radiographs, respectively. In 188 cases, the P wave displayed typical changes, and 97.8% (184/188) catheters were successfully placed correctly. At the peak P wave, the amplitude of the peak P wave was 8.64 times greater than that of the basal P wave, and the P/R ratio was 0.61. When the arm was abducted to 90°, the amplitude of the P wave dropped to 57% of its peak, P/R decreased from 0.61 to 0.34, and the catheter tip moved cephalad 1.00 and 0.77 vertebral body units in male and female patients, respectively. Peripherally inserted central catheter moves toward the heart when the arm position changes from abduction to adduction. Peripherally inserted central catheter tip placement at the peak P wave with patient's arm in adduction is accurate and can prevent the catheter from advancing too low. R wave can function as a reference for observing P wave changes during peripherally inserted central catheter placement.

Effect of Arm Position on Image Quality and Radiation Dose in Multidetector Computed Tomography

Background: Abdominal CT using a tube-current modulation technique may result in artifacts due to changes in the position of the patient’s arms, resulting in poor image quality and excessive radiation exposure. To solve these problems, the patient’s arm is positioned mainly on the head or outside the examination area. Objectives: An optimization method to acquire high-quality images in CT examination by comparing the radiation dose and image according to the change in arm position and the use of the tube-current modulation method in CT examination. Materials and Methods: To analyze the CT images, the mean, standard deviation (SD), and coefficient of variation (COV) of the Hounsfield unit (HU) of the CT were obtained by measuring the pixel values of the heart, chest, lung, and bone using region of interest (ROI) manage. The dose of computed tomography dose index (CTDI) and dose length product (DLP) according to the position of the arm. Results: The arms up position of CTDIvol and DLP values were lower than the arms down position. In the z-axis thickness modulation (Z-DOM), the tube current increased in the shoulders, decreased in the lungs, and increased in the abdomen. There was no artifact when the arms were raised, but an artifact was present when the arm was lowered. The calculated peak signal-to-noise ratio (PSNR) for the Z-DOM application in the CT scan of the anthropomorphic phantom by applying automatic exposure control (AEC) was 38.21 dB. There was no significant difference between SD and COV using Z-DOM and the fixed tube current technique (P > 0.05). Noise in the image increased when the arm was raised, and dose increased in the thyroid and upper chest. Conclusion: The position of the upper arms directly affects the image in the MDCT imaging of the anthropomorphic phantom. Therefore, it is possible to increase the quality of the image by reducing the amount of artifacts and the amount of radiation by orienting the arms upward. This optimal test method could be used in clinical practice to achieve high image quality and low noise in the MDCT of trauma patients.

Can visual feedback on upper trapezius high-density surface electromyography increase time to task failure of an endurance task?

We investigate whether visual feedback on the spatial distribution of upper trapezius muscle activity can prolong time to task failure of sustained shoulder abduction. Surface electromyographic signals were acquired with a 13x5 grid of high-density electromyography (HDEMG) electrodes from the right upper trapezius muscle of 12 healthy volunteers as they performed sustained isometric shoulder abduction at 20% of their maximum voluntary contraction torque (MVC) until volitional exhaustion. Data were collected in two sessions; one with HDEMG visual feedback on the spatial distribution of upper trapezius activity and one without feedback. Although the HDEMG amplitude maps could be voluntarily modified by the participants during the feedback condition (significant shift in the barycenter of activity towards the cranial direction, P = 0.038), this did not influence endurance time (total endurance time with HDEMG feedback: 149.01 ± 77.07 s, no feedback 141.74 ± 60.93 s, P = 0.532). Future studies should assess whether endurance performance can be enhanced by allowing changes in arm position during the task (changing fiber tension-length relationships), by providing a more individual motor strategy, and/or by manipulating the colours used for the HDEMG maps (lighter colours for higher contraction intensities).

Change in arm position alters DC and AC components of photoplethysmogram signals

Change in arm position alters DC and AC components of photoplethysmogram signals

Morphological and hemodynamical alterations in brachial artery and cephalic vein. An image-based study for preoperative assessment for vascular access creation.

The current study aims to computationally evaluate the effect of right upper arm position on the geometric and hemodynamic characteristics of the brachial artery (BA) and cephalic vein (CV) and, furthermore, to present in detail the methodology to characterise morphological and hemodynamical healthy vessels. Ten healthy volunteers were analysed in two configurations, the supine (S) and the prone (P) position. Lumen 3D surface models were constructed from images acquired from a non-contrast MRI sequence. Then, the models were used to numerically compute the physiological range of geometric (n=10) and hemodynamic (n=3) parameters in the BA and CV. Geometric parameters such as curvature and tortuosity, and hemodynamic parameters based on wall shear stress (WSS) metrics were calculated with the use of computational fluid dynamics. Our results highlight that changes in arm position had a greater impact on WSS metrics of the BA by altering the mean and maximum blood flow rate of the vessel. Whereas, curvature and tortuosity were found not to be significantly different between positions. Inter-variability was associated with antegrade and retrograde flow in BA, and antegrade flow in CV. Shear stress was low and oscillatory shear forces were negligible. This data suggests that deviations from this state may contribute to the risk of accelerated intimal hyperplasia of the vein in arteriovenous fistulas. Therefore, preoperative conditions coupled with post-operative longitudinal data will aid the identification of such relationships.

Structural Design of Industrial Robot

The robot is a planar joint robot composed of three degrees of freedom. Its main function is to carry out the handlingand movement of precision instruments and objects. Because of the small size, simple transmission principle, iswidely used in the electrical and electronic industry, household appliances, precision machinery industry and otherfi elds. The whole system consists of robot, robot arm, joint, stepper motor drive system and so on. Through the degreeof freedom of the stepper motor drive, complete the robot, the robot arm position changes. Specifi c design content:synchronous toothed belt drive design, screw nut design, the output shaft and shell design, stepper motor selection.On the basis of checking the strength of the structure, we optimize the structure of the robot.

Continuous Trajectory Point Control Research of Six Degree of Freedom Mechanical Intelligent Arm Position

In view of the low pointing accuracy problem of the hanging wire weight control method adopted in current mechanical arm control, for the control of the mechanical arm, a mechanical intelligent arm position control method based on continuous trajectory point control is proposed to improve the control accuracy of mechanical intelligent arm. The kinematic behavior planning model of the mechanical arm in six degree of freedom motion space is constructed. The end-effect inverse kinematics decomposition method is used to obtain the vector set of mechanical arm joint rotation. The parametric self-tuning regulation is used to control parameters optimization. Continuous trajectory point control method is adopted to improve the accuracy of mechanical intelligent arm position change and achieve high-precision arm control. Simulation results show that six degree of freedom mechanical intelligent arm accuracy control has higher precision, minimized convergence error and higher robustness with this control method.

Real-time robustness evaluation of regression based myoelectric control against arm position change and donning/doffing.

There are some practical factors, such as arm position change and donning/doffing, which prevent robust myoelectric control. The objective of this study is to precisely characterize the impacts of the two representative factors on myoelectric controllability in practical control situations, thereby providing useful references that can be potentially used to find better solutions for clinically reliable myoelectric control. To this end, a real-time target acquisition task was performed by fourteen subjects including one individual with congenital upper-limb deficiency, where the impacts of arm position change, donning/doffing and a combination of both factors on control performance was systematically evaluated. The changes in online performance were examined with seven different performance metrics to comprehensively evaluate various aspects of myoelectric controllability. As a result, arm position change significantly affects offline prediction accuracy, but not online control performance due to real-time feedback, thereby showing no significant correlation between offline and online performance. Donning/doffing was still problematic in online control conditions. It was further observed that no benefit was attained when using a control model trained with multiple position data in terms of arm position change, and the degree of electrode shift caused by donning/doffing was not severely associated with the degree of performance loss under practical conditions (around 1 cm electrode shift). Since this study is the first to concurrently investigate the impacts of arm position change and donning/doffing in practical myoelectric control situations, all findings of this study provide new insights into robust myoelectric control with respect to arm position change and donning/doffing.

A Pulse Wave Velocity Based Method to Assess the Mean Arterial Blood Pressure Limits of Autoregulation in Peripheral Arteries

Background: Constant blood flow despite changes in blood pressure, a phenomenon called autoregulation, has been demonstrated for various organ systems. We hypothesized that by changing hydrostatic pressures in peripheral arteries, we can establish these limits of autoregulation in peripheral arteries based on local pulse wave velocity (PWV).Methods: Electrocardiogram and plethysmograph waveforms were recorded at the left and right index fingers in 18 healthy volunteers. Each subject changed their left arm position, keeping the right arm stationary. Pulse arrival times (PAT) at both fingers were measured and used to calculate PWV. We calculated ΔPAT (ΔPWV), the differences between the left and right PATs (PWVs), and compared them to the respective calculated blood pressure at the left index fingertip to derive the limits of autoregulation.Results: ΔPAT decreased and ΔPWV increased exponentially at low blood pressures in the fingertip up to a blood pressure of 70 mmHg, after which changes in ΔPAT and ΔPWV were minimal. The empirically chosen 20 mmHg window (75–95 mmHg) was confirmed to be within the autoregulatory limit (slope = 0.097, p = 0.56). ΔPAT and ΔPWV within a 20 mmHg moving window were not significantly different from the respective data points within the control 75–95 mmHg window when the pressure at the fingertip was between 56 and 110 mmHg for ΔPAT and between 57 and 112 mmHg for ΔPWV.Conclusions: Changes in hydrostatic pressure due to changes in arm position significantly affect peripheral arterial stiffness as assessed by ΔPAT and ΔPWV, allowing us to estimate peripheral autoregulation limits based on PWV.