The authors disclose receipt of the following financial support for the research, authorship, and/or publication of this article: National Key R&#38;D Program of China, Grants No. 2018YFC2000900, National Natural Science Foundation of China, Grants No. 11802171, Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, and the Talent Program of Shanghai University of Engineering Science.

1. Fabrication of CH
<ol>
	<li>Programming
	<ol>
		<li>Open the STAT-Ds 615 MP stocking software and select Plain fabric to create a new sock construction.</li>
		<li>Select the following contents in order: Double welt 1 feed, Transfer without pattern, Plain medical leg from double welt 1 feed, Begin heel from plain medical leg, End of heel and plain medical foot, Begin toe from plain foot 1f, Plain toe with rosso and clip, Sock release without turning device, and End of sock. Press OK button to complete the sock design.</li>
		<li>Select 200 for the Needle and export the program file onto a USB flash disk.</li>
		<li>Switch to Quasar to change the fabrication parameters and click any blue button in the GRADUATION row to open a new window. For fabricating the CH with different structure, enter 500 in the Cylinder S and E columns and click OK to complete the setup.</li>
		<li>Click any one of blue buttons in the ELASTIC MOTORS row to open a new window and enter 800 in the WELT rows and the Cylinder S and E columns. In the Medical leg row, enter 800 in the S column and 650 in column E. Then enter 650 in the ANKLE row and the S and E column and click OK to complete the setup.</li>
		<li>Repeat steps 1.1.4 and 1.1.5. Respectively enter 350 and 650 when adjusting GRADUATION. Respectively enter 1000 and 1200 in the WELT row, and keep the ANKLE row as 650 when adjusting ELASTIC MOTORS. 
		NOTE: The elastic motors could control the tension of the elastane yarn. Fabricated CH should ensure that the tightness gradually increased from knee to ankle. Here, the elastic motor number in the ANKLE is fixed (650), while the elastic motor number in the WELT is changed (800, 1000, 1200) to fabricate CH samples with different tightness. The graduation could control the loop size of the whole CH sample. Larger loops usually result in looser CH, while smaller loops always generate a tight CH sample. Thus, we respectively input 350, 500, and 650 as the graduation. Finally, program files with altered elastic motors and graduation are generated.</li>
	</ol>
	</li>
	<li>Knitting
	<ol>
		<li>Prepare the ground yarn and elastane yarn on the CH fabrication machine.</li>
		<li>Turn on the machine, insert the USB flash disk, and select the program file obtained from step 1.1.3. The machine will automatically fabricates the CH sample. Alphabetically number these samples from A to I. 
		NOTE: Table 1 displays the fabrication parameters of these CH samples.</li>
	</ol>
	</li>
</ol>
2. Direct measurement
NOTE: All of the CH samples should be conditioned for 24 h in standard atmospheric environment (23 &#176;C, 65% relative humidity [RH]) prior to measurement. The CH samples are dressed on the artificial lower limb to test the pressure value. All measurements should be performed three times to calculate the average value and decrease the error.
<ol>
	<li>Mark the lines on the CH sample.
	<ol>
		<li>Place a sample onto an artificial lower limb.</li>
		<li>Mark six, evenly spaced, circle lines on the compressed hosiery sample dressings from the knee to the ankle. Number these lines as line 6, 5, 4.... These lines divide the CH sample into five parts, as shown in Figure 1a.</li>
	</ol>
	</li>
	<li>Pressure measurement
	<ol>
		<li>To perform a pressure measurement, place the interface pressure sensors under part 1 of the compressed hosiery sample in the anterior, posterior, medial, and lateral directions.</li>
		<li>In the measurement software, select the appropriate serial port COM and set the minimum threshold value as 0.</li>
		<li>Click Start Measurement. Real-time channel 1~4 will display the pressure data</li>
		<li>When the pressure is stable, click Stop Measurement. The software will automatically export the pressure data.</li>
		<li>Place the interface press sensors under other parts of CH sample and repeat steps 2.2.1&#8722;2.2.4.</li>
	</ol>
	</li>
	<li>After pressure measurement of the whole CH sample, remove the CH sample and then dress another CH sample on the artificial lower limb to prepare for the next measurement.</li>
</ol>
3. Indirect measurement
NOTE: The experiments here measure the necessary parameters of the cone and cylinder model. These parameters contain the deformation and structure parameters of the dressing and undressed CH samples, thickness, tension. All the CH samples should be conditioned for 24 h in standard atmospheric environment (23 &#176;C, 65% RH) prior to measurement. All measurements should be performed three times to calculate the average value and decrease the error.
<ol>
	<li>Structure parameter measurement of CH samples
	<ol>
		<li>Place a CH sample on the&#160;artificial lower limb.</li>
		<li>Use a measuring tape to measure the total length (L) of the sample.</li>
		<li>Use a pick glass to measure the course density and the Wales density of each divided part.</li>
		<li>Measure the circumference (c) of each circle line with measuring tape. Then, calculate the circumference (w) of each divided part of the CH sample by averaging the circumferences (c) of the neighboring circle lines.</li>
		<li>When all of the structure parameter measurements have been acquired, remove the sample from the limb. And then dress another sample on the artificial lower limb to prepare for next measurement.</li>
		<li>Measure the circumference (c&#8217;) of each circle line of an undressed CH sample. Then, calculate the circumference (w&#8217;) of each divided part of CH sample by averaging the circumferences of the neighboring circle lines.</li>
		<li>Measure the course density and the wales density of the same divided part of the undressed CH sample.</li>
	</ol>
	</li>
	<li>Thickness measurement
	<ol>
		<li>Smooth a compressed hosiery sample onto the steel round table of the thickness gauge.</li>
		<li>Turn on the thickness gauge to let another steel round slowly fall down to&#160;press onto&#160;the sample piece. The screen will display&#160;the thickness data (t).</li>
		<li>Move the sample and repeat steps 3.2.1 and 3.2.2 to test the thickness of other parts.</li>
	</ol>
	</li>
	<li>Tensile experiment
	<ol>
		<li>Cut all the CH samples along the marked circle lines.</li>
		<li>Clamp one piece of sample into the tensile testing instrument.</li>
		<li>Open the software for tensile experiment, input 5 N as the initial tension, 60 mm/,min&#160;as the tensile speed, and 200 mm as the initial tensile length. Keep the default setup for the other fields.</li>
		<li>When all of the measurement parameters have been set, click START to run tensile experiment automatically. The computer will export real-time stress and strain on the screen. The tensile experiment will automatically stop when the CH piece is broken.</li>
		<li>Then replace the broken piece of sample with a new sample piece for the next round of testing and repeat steps 3.3.3&#8722;3.3.4.</li>
	</ol>
	</li>
</ol>
4. Theoretical calculation
NOTE: The cylinder model and cone model are employed in the indirect measurement to calculate the exerted pressure. Each CH sample is separated into five parts from the knee to the ankle. In the cylinder model, human limbs are described as a cylinder with a constant radius while the radius of the limb is variable in the cone model. The schematic diagrams are illustrated in Figure 1b and Figure 1c. All calculation steps are performed in Matlab 2018a and the calculation program can be found in the Supplemental Coding File.
<ol>
	<li>Cylinder model
	<ol>
		<li>According to the measured results obtained from step 3.1.3&#8722;3.1.5, calculate the circumference difference (D) between the dressed CH and the undressed CH using the following equation: 
		<img alt="Equation 1" src="/files/ftp_upload/60852/60852equ01.jpg" /> 
		where i is the number of CH piece that is separated by marked circle lines. It is numbered according to the circle line number.</li>
		<li>Fit the stress-strain curve obtained in step 3.3.4 using an appropriate linear equation. The slope of the linear equation is the tensile modulus E.</li>
		<li>Calculate the tension in the dressing CH (T) by employing the equation: 
		<img alt="Equation 2" src="/files/ftp_upload/60852/60852equ02.jpg" /> 
		NOTE: Supplemental Table 1 displays the obtained original tensile modulus E and tension T.</li>
		<li>Based on the cylinder model and the thin wall assumption15, express the exerted pressure of CH piece i as: 
		<img alt="Equation 3" src="/files/ftp_upload/60852/60852equ03.jpg" /> 
		where r is the radius of divided part and equals to <img alt="Equation 5" src="/files/ftp_upload/60852/60852equ05.jpg" />, t is the thickness of CH sample, and T is the tension calculated from step 4.1.3.</li>
		<li>Calculate all the exerted pressure of CH pieces following steps 4.1.1&#8722;4.1.4.</li>
	</ol>
	</li>
	<li>Cone model
	<ol>
		<li>Calculate the exerted pressure of the CH piece i by the following equation14: 
		<img alt="Equation 4" src="/files/ftp_upload/60852/60852equ04.jpg" /> 
		where rc is the radius of circle line and equals to <img alt="Equation 6" src="/files/ftp_upload/60852/60852equ06.jpg" />, T is the tension calculated from step 4.1.3, l is the length of each divided piece and can be calculated by l = L/5 (herein, L is measured following step 3.1.2).</li>
	</ol>
	</li>
</ol>

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T., Kwok, Y. L., Li, Y., Ying, M. 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P., Ghosh, S., Mukhopadhyay, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mathematical+modeling+to+predict+the+sub-bandage+pressure+on+a+cone+limb+for+multi-layer+bandaging.">Mathematical modeling to predict the sub-bandage pressure on a cone limb for multi-layer bandaging.</a> Medical Engineering &amp; Physics. 38 (9), 917-921 (2016).</li><li>Zhang, L. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+structure+and+pressure+characteristics+of+graduated+compression+stockings:+experimental+and+numerical+study.">The structure and pressure characteristics of graduated compression stockings: experimental and numerical study.</a> Textile Research Journal. 89 (23-24), 5218-5225 (2019).</li></ol>

The authors have nothing to disclose.

In this study, we provide two methods to measure the exerted pressure of CH samples and these methods can be used to measure the exerted pressure of other garment dressing on the skin. In the direct method, the CH sample is dressed on the artificial lower limb and the interface sensor is placed under the CH sample. The pressure value can be displayed on the screen using data collection software. To compare with the direct method, we also supply an indirect method. Two theories involving the cylinder model and the cone mo...

Compressed hosiery (CH) provides pressure on the lower limb. It can press the skin and further change the vein radius. Thus, the venous blood flow velocity is raised when the patient is dressed in compressed hosiery. CH and other compressed garments could improve venous circulation in the lower limbs1,2,3,4. The therapeutic performance was dependent on the pressure characteristics of the CH5. It was widely believed that raw material and CH structure have a great influence on CH pressure characteristics. Elastane yarn in CH was primarily responsible for the pressure characteristics according to some published research6. For example, Chattopadhyay7 reported the pressure characteristics of knitted circular stretch fabrics by adjusting the feed tension of elastane yarn. In addition, Ozbayraktar8 also determined that the density of elastane yarn increased while the extensibility of CH decreased. Additionally, loop length9, knitted pattern9, and linear density of the yarns7,10 also exhibited the effects on the pressure characteristics.
A numerical model was presented to inspect the generation mechanism of the pressure characteristics of the CH. Laplace&#8217;s Law was used for predicting the pressure values. Thomas11 introduced Laplace&#8217;s Law into pressure prediction by combining pressure, tension, and body limb size. Similar work also was reported by Maklewska12. To precisely predict the pressure values exerted by the fabric, they presented a semi-empirical equation that was composed of the fitted stress-strain equation and Laplace&#8217;s Law. Additionally, Young&#8217;s modulus was presented by Leung13 to describe elongation of the CH.
The above-mentioned numerical studies showed deviated experimental results due to ignorance of the CH thickness14. In addition, some researchers believed that the hypothetical cylinder involved in Laplace&#8217;s Law was inappropriate to describe the body limbs because the radius of the lower limbs from the thigh to the ankle is not constant but gradually decreases. By combining the thick cylinder theory and Laplace&#8217;s Law, Dale14 and Al Khaburi15,16 respectively proposed numerical models to investigate the pressure exerted by the CH with multiple layers. Sikka17 presented a new cone model with a gradually decreased radius from the thigh to the ankle.
The pressure characteristics intrinsic to CH were difficult to quantitatively study because most of the experimental CHs in previous studies were usually purchased commercially. The influences such as pattern, yarn, raw material were uncontrollable. Therefore, in this study, the experimental CHs were controllably fabricated in house. Moreover, this study aims to provide two methods involving direct method and indirect method to measure the pressure characteristics. In the direct method, an interface sensor (Table of Materials) is placed between the skin and textiles to directly measure the pressure value. On the other hand, in the indirect method, the tension and some structure parameters of the CH sample dressing on the artificial lower limb are firstly measured. Then, the results are substituted into the cone model and the cylinder model to calculate the pressure value. The pressure values obtained as a result of the two methods are contrasted and analyzed to find a more appropriate model. The presented methods provide a guideline to the experimental measurement of pressure exerted by the compressed garment.

<table><tbody><tr><td>Artificial lower limb</td><td>Dayuan, Laizhou Electron Instrument Co., Ltd.</td><td>YG065C</td><td>Used for measuring the strength of stockings. The employing test standard is ISO 13934-1-2013, metioned this in section 3.3</td></tr><tr><td>CH fabrication machine</td><td>Hongda, Co., Ltd.</td><td>YG14N</td><td>Used for measuring the thickness of stockings, the test standard is ISO 5084:1996, metioned this in section 3.2</td></tr><tr><td>Elastane yarn</td><td>MathWorks, Co., Ltd.</td><td>2018a</td><td>Used for calculating the pressure, mentioned this in section 4.</td></tr><tr><td>FlexiForce interface pressure sensors</td><td>Qile, Co., Ltd.</td><td>Y115B</td><td>It is composed of magnifying glass with a fixed ruler. Used for counting the loops number per cm in the fabricated CH, metioned this in the sction 3.1.3 and 3.1.7.</td></tr><tr><td>FlexiForce measurement software</td><td>Santoni, Co., Ltd.</td><td>GOAL 615MP</td><td>Used for fabricating stockings, metioned this in section 1.2</td></tr><tr><td>Ground yarn</td><td>Santoni, Co., Ltd.</td><td></td><td>It is a kind of coverd yarn which is composed of 80% rubber and 20% viscose, metioned this in section 1.2.1</td></tr><tr><td>Matlab software</td><td>Santoni, Co., Ltd.</td><td></td><td>It is a kind of coverd yarn which is composed of 30% polyamide and 70% cotton, metioned this in section 1.2.1</td></tr><tr><td>Mechanical testing instrument and software</td><td>Santoni, Co., Ltd.</td><td>GOAL 615MP</td><td>Used for programing the fabrication parameters, metioned this in section.1.1</td></tr><tr><td>Pick glass</td><td>Shenmei, Inc.</td><td>F002</td><td>A standard artificial femal with 160 cm height. The size was consited with Chinese Standard GB 10000-1988. The artificial femal was made by glass-reinforced plywood and covered by fabric. Mentioned this in section 2.1.</td></tr><tr><td>STAT-Ds 615 MP stocking software</td><td>Tekscan, Inc.</td><td>A201</td><td>Used for measuring the pressure on the skin, metioned this in section 2.2.1</td></tr><tr><td>Thickness gauge</td><td>Weike, Co., Ltd.</td><td>1lbs</td><td>Used for recording the pressure, metioned this in section 2.2.2-2.2.4.</td></tr></tbody></table>

fabrication of compressed hosiery and measurement of its pressure characteristic exerted on the lower limbs

This article reports the pressure characteristic measurement of compressed hosiery via direct and indirect methods. In the direct method, an interface sensor is used to measure the pressure value exerted on the lower limbs. In the indirect method, the necessary parameters mentioned by the cone and cylinder model are tested to calculate the pressure value. The necessary parameters involve course density, wales density, circumference, length, thickness, tension, and deformation of the compressed hosiery. Compared with the results of the direct method, the cone model in the indirect method is more suitable for calculating the pressure value because the cone model considers the change in radius of the lower limb from the knee to the ankle. Based on this measurement, the relationship among fabrication, structure, and pressure is further investigated in this study. We find that graduation is the main influence that can change the wales density. On the other hand, elastic motors directly affect the course density and the circumference of the stockings. Our reported work provides the fabrication-structure-pressure relationship and a design guide for gradually compressed hosiery.

Course density gradually increases from the knee to the ankle in Figure 2a. This is explained by the influence of the elastic motor. From the knee to the ankle, the increased elastic motor gradually generates increasing tension from part 5 to part 1 in the CH fabrication process. Thus, the CH sample is gradually frapped and the loop number per cm is increased in the course direction. The experimental lines in Figure 2b can be divided into three groups: ABC, DEF,...

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Fabrication of Compressed Hosiery and Measurement of its Pressure Characteristic Exerted on the Lower Limbs

This article reports fabrication, structure and pressure measurement of compressed hosiery by employing direct and indirect methods.

This article reports the pressure characteristic measurement of compressed hosiery via direct and indirect methods. In the direct method, an interface ...

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2.3K Views.  Shanghai University of Engineering Science. Dit artikel rapporteert fabricage, structuur en drukmeting van gecomprimeerde kousen door gebruik te maken van directe en indirecte methoden.

Video: Fabrication of Compressed Hosiery and Measurement of its Pressure Characteristic Exerted on the Lower Limbs

Wicking Tests for Unidirectional Fabrics: Measurements of Capillary Parameters to Evaluate Capillary Pressure in Liquid Composite Molding Processes

During impregnation of a fibrous reinforcement in liquid composite molding (LCM) processes, capillary effects have to be understood in order to identify their influence on void formation in composite parts. Wicking in a fibrous medium described by the Washburn equation was considered equivalent to a flow under the effect of capillary pressure according to the Darcy law. Experimental tests for the characterization of wicking were conducted with both carbon and flax fiber reinforcement. Quasi-unidirectional fabrics were then tested by means of a tensiometer to determine the morphological and wetting parameters along the fiber direction. The procedure was shown to be promising when the morphology of the fabric is unchanged during capillary wicking. In the case of carbon fabrics, the capillary pressure can be calculated. Flax fibers are sensitive to moisture sorption and swell in water. This phenomenon has to be taken into account to assess the wetting parameters. In order to make fibers less sensitive to water sorption, a thermal treatment was carried out on flax reinforcements. This treatment enhances fiber morphological stability and prevents swelling in water. It was shown that treated fabrics have a linear wicking trend similar to those found in carbon fabrics, allowing for the determination of capillary pressure.

An experimental method to measure geometrical parameters and the apparent advancing contact angles describing capillary wicking in unidirectional synthetic and natural fabrics is proposed. These parameters are mandatory for the determination of the capillary pressures that must be taken into account for liquid composite molding (LCM) applications.

During impregnation of a fibrous reinforcement in liquid composite molding (LCM) processes, capillary effects have to be understood in order to identify ...

Computerized Dynamic Posturography for Postural Control Assessment in Patients with Intermittent Claudication

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic conditions. As part of a diagnostic assessment, the early detection of postural deficits is important so that appropriate and targeted interventions can be prescribed. The Sensory Organization Test (SOT) on the EquiTest determines an individual&#39;s use of the sensory systems (somatosensory, visual, and vestibular) that are responsible for postural control. Somatosensory and visual input are altered by the calibrated sway-referenced support surface and visual surround, which move in the anterior-posterior direction in response to the individual&#39;s postural sway. This creates a conflicting sensory experience. The Motor Control Test (MCT) challenges postural control by creating unexpected postural disturbances in the form of backwards and forwards translations. The translations are graded in magnitude and the time to recover from the perturbation is computed.
Intermittent claudication, the most common symptom of peripheral arterial disease, is characterized by a cramping pain in the lower limbs and caused by muscle ischemia secondary to reduced blood flow to working muscles during physical exertion. Claudicants often display poor balance, making them susceptible to falls and activity avoidance. The Ankle Brachial Pressure Index (ABPI) is a noninvasive method for indicating the presence of peripheral arterial disease and intermittent claudication, a common symptom in the lower extremities. ABPI is measured as the highest systolic pressure from either the dorsalis pedis or posterior tibial artery divided by the highest brachial artery systolic pressure from either arm. This paper will focus on the use of computerized dynamic posturography in the assessment of balance in claudicants.

Individuals with intermittent claudication exhibit poor balance compared to healthy controls. Computerized dynamic posturography is an objective method for measuring an individual's postural responses to balance disturbances. This provides an objective reflection of the person&#x2019;s ability to respond to situations under which sensory stimuli are altered and unexpected perturbations occur.

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic ...

Medicine

Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds

Gait termination caused by unexpected stimulus is a common occurrence in everyday life. This study presents a protocol to investigate the lower-limb biomechanical changes that occur during unplanned gait termination (UGT) under different walking speeds. Fifteen male participants were asked to perform UGT on a walkway at normal walking speed (NWS) and fast walking speed (FWS), respectively. A motion analysis system and plantar pressure platform were applied to collect lower-limb kinematic and plantar pressure data. Paired-sampled T-test was used to examine the differences in lower-limb kinematics and plantar pressure data between two walking speeds. The results showed larger range of motion in the hip, knee, and ankle joints in the sagittal plane as well as plantar pressure in forefoot and heel regions during UGT at FWS when compared with NWS. With the increase in walking speed, subjects exhibited different lower-limb biomechanical characteristics that show FWS associated with greater potential injury risks.

This study compared the biomechanical characteristics of the lower extremity during unplanned gait termination under different walking speeds. The lower-limb kinematic and kinetic data from fifteen subjects with normal and fast walking speeds were collected using a motion analysis system and plantar pressure platform.

Gait termination caused by unexpected stimulus is a common occurrence in everyday life. This study presents a protocol to investigate the lower-limb ...

Behavior

Revolutionizing Stroke Rehabilitation with Enhanced Grasping and Finger Recovery

A Flexible Wearable Supernumerary Robotic Limb for Chronic Stroke Patients

In this study, we present a flexible wearable supernumerary robotic limb that helps chronic stroke patients with finger rehabilitation and grasping movements. The design of this innovative limb draws inspiration from bending pneumatic muscles and the unique characteristics of an elephant's trunk tip. It places a strong emphasis on crucial factors such as lightweight construction, safety, compliance, waterproofing, and achieving a high output-to-weight/pressure ratio. The proposed structure enables the robotic limb to perform both envelope and fingertip grasping. Human-robot interaction is facilitated through a flexible bending sensor, detecting the wearer's finger movements and connecting them to motion control via a threshold segmentation method. Additionally, the system is portable for versatile daily use. To validate the effectiveness of this innovation, real-world experiments involving six chronic stroke patients and three healthy volunteers were conducted. The feedback received through questionnaires indicates that the designed mechanism holds immense promise in assisting chronic stroke patients with their daily grasping activities, potentially improving their quality of life and rehabilitation outcomes.

Author Spotlight: Enhancing Grasping Abilities for Hemiplegic Patients with Flexible Robotic Limbs 

This protocol introduces a flexible wearable supernumerary robotic limb tailored to assist in finger rehabilitation for stroke patients. The design incorporates a bending sensor to facilitate seamless human-robot interaction. Validation through experiments involving both healthy volunteers and stroke patients underscores the efficacy and dependability of the proposed study.

In this study, we present a flexible wearable supernumerary robotic limb that helps chronic stroke patients with finger rehabilitation and grasping ...

Application of Consistent Massage-Like Perturbations on Mouse Calves and Monitoring the Resulting Intramuscular Pressure Changes

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of massage on skeletal muscles, the molecular mechanisms behind are poorly understood. We have recently developed a simple device to apply local cyclical compression (LCC), which can generate intramuscular pressure waves with varying amplitudes. Using this device, we have demonstrated that LCC modulates inflammatory responses of macrophages in situ and alleviates immobilization-induced muscle atrophy. Here, we describe protocols for the optimization and application of LCC as a massage-like intervention against immobilization-induced inflammation and atrophy of skeletal muscles of mouse hindlimbs. The protocol that we have developed can be useful for investigating the mechanism underlying beneficial effects of physical exercise and massage. Our experimental system provides a prototype of the analytical approach to elucidate the mechanical regulation of muscle homeostasis, although further development needs to be made for more comprehensive studies.

Here we describe the protocols for applying defined mechanical loads to mouse calves and for monitoring the concomitant intramuscular pressure changes. The experimental systems that we have developed can be useful for investigating the mechanism behind the beneficial effects of physical exercise and massage.

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of ...

Immunology and Infection

Evaluation of Patients' Posture and Gait Profile After Lumbar Fusion Surgery by Video Rasterstereography and Treadmill Gait Analysis

This protocol provides guidance on how to perform high resolution video rasterstereography and treadmill gait analysis on patients after lumbar fusion surgery to obtain results about altered variables of gait and posture. These observed changes can then be correlated with the patient-reported outcome measure of pain relief. The rasterstereographic device projects lines of parallel light onto the surface of the tested subject&#39;s back. The deformation of these lines is recognized by the device. From these data, a special software then generates a 3-D profile based on the principle of triangulation. With an inaccuracy of only 0.2 mm it can measure changes in posture at very high precision. Gait and stance parameters are recorded using a treadmill equipped with an electric sensor mat that contains 10,200 miniature force sensors in the registering zone under the belt. Initial walking speed on the treadmill is 0.5 km/h. Speed is then gradually increased by increments of 0.1 km/h until each subject reaches his or her individual maximum well tolerable walking speed. At this speed, parameters are recorded during a 20 s measurement interval. Subjects are tested barefoot and without holding a handrail. Among various other parameters, stride width, step length, stance phase and foot rotation are measured. Both methods used reportedly have a high intra- and inter-observer reliability. The advantage of these highly accurate techniques is that they offer an objective and very detailed perspective on changes in the patient&#39;s posture and gait. Due to the amount of data generated, these techniques are, however, not so much suitable for everyday routine use, but rather interesting to scientifically evaluate long term alterations in posture and gait in patients like for example after lumbar fusion surgery.

Here, we present a protocol to analyze the posture and the gait of patients after lumbar fusion surgery by means of high-resolution video rasterstereography and a treadmill equipped with an integrated sensor mat. Allowing critical functional postoperative evaluation on a less subjective level may enhance accuracy and reliability of indication for surgery.

This protocol provides guidance on how to perform high resolution video rasterstereography and treadmill gait analysis on patients after lumbar fusion ...

A Novel Non-invasive Method for the Detection of Elevated Intra-compartmental Pressures of the Leg

Acute Compartment Syndrome is a devastating consequence of musculoskeletal trauma. Currently the diagnosis is based on clinical signs and symptoms, and while adjuncts such as invasive intra-compartmental pressure measurements are often used to corroborate the physical exam findings, there remains no reliable objective test to aid in the decision to perform a decompressive fasciotomy. In a cadaver model of compartment syndrome, an ultrasound (US) based method has been shown to be a reliable measurement of increased intra-compartmental pressure. An absolute pressure of &#62;100 mbar or a difference of 50 mbar in the CFFP between the legs can be considered pathologic. Using an ultrasound transducer, coupled with a pressure sensor, the pressure needed to flatten the superficial fascia of the anterior compartment of lower legs (Compartment Fascia Flattening Pressure [CFFP]) can be measured. The CFFP of the injured leg is compared to the CFFP of the uninjured leg. This US measured index can then serve as an adjunct to the physical exam in evaluating injured lower extremities and assessing the need for decompressive fasciotomy. The advantages of this protocol include: being a non-invasive method and an easily reproducible technique.

An ultrasound probe coupled with a pressure sensor is used to assess the intra-compartmental pressure of the leg by directly measuring the compartment fascia flattening pressure (CFFP). This non-invasive protocol will provide reliable assessment of the pressure inside the anterior muscular compartment of the lower leg.

Acute Compartment Syndrome is a devastating consequence of musculoskeletal trauma. Currently the diagnosis is based on clinical signs and symptoms, and ...

Lower Limb Biomechanical Analysis of Healthy Participants

Biomechanical analysis techniques are useful in the study of human movement. The aim of this study was to introduce a technique for the lower limb biomechanical assessment in healthy participants using commercially available systems. Separate protocols were introduced for the gait analysis and muscle strength testing systems. To ensure maximum accuracy for gait assessment, attention should be given to the marker placements and self-paced treadmill acclimatization time. Similarly, participant positioning, a practice trial, and verbal encouragement are three critical stages in muscle strength testing. The current evidence suggests that the methodology outlined in this article may be effective for the assessment of lower limb biomechanics.

This article introduces a comprehensive experimental methodology on two of the latest technologies available to measure the lower limb biomechanics of individuals.

Biomechanical analysis techniques are useful in the study of human movement. The aim of this study was to introduce a technique for the lower limb ...

Evaluation of Plantar Fasciitis Using Windlass Length Change

Predictive Measurement for Windlass Change in Length and Selected Treatment Outcomes in Chronic Plantar Fasciitis

Approximately 10% of patients with plantar fasciitis experience persistent and often severe symptoms, though little is known about its etiology. The goal of this study was to employ an objective, simple, and economical approach to measure the change in length of the windlass and assess the efficiency of a specified therapy protocol applied in this study over a one-month period. Age, weight, normal foot type, and gender were employed as matching factors in a matched design. Fifty individuals diagnosed with unilateral plantar fasciitis and an equal number of healthy volunteers all fulfilled the inclusion criteria and took part in this research. Pain assessment utilized a visual analogue scale and the pain subscale of the foot function index, while a valid goniometric method was employed to evaluate weight-bearing windlass, dorsiflexion and plantar flexion ranges of motion. Additionally, foot plantar pressure (both static and dynamic measures) and tape measurement of windlass change in length were assessed. The assessment was completed by all patients before and after their treatment program. Normal subjects were evaluated for control. Treatment methods encompassed ultrasonic therapy, application of an electrical heating pad, utilization of a night splint, engagement in stretching activities for the plantar aponeurosis and Achilles tendon, as well as both extrinsic and intrinsic strengthening exercises. After one month, the patients were reassessed and compared to control volunteers. In those suffering from plantar fasciitis, a substantial link was found between clinical measurements (tape measurement, windlass range of motion) and foot plantar pressure, indicating improvement. The chosen treatment protocol was effective in 96% of patients. For windlass length change, the measurement technique was found to be valid and objective. The chosen therapy procedure was successful in treating persistent plantar fasciitis in patients.

This protocol presents an objective, easy, and economical method to measure the change in length of the windlass in plantar fasciitis and assess the effectiveness of a selected treatment procedure employed in this study over a one-month period.

Approximately 10% of patients with plantar fasciitis experience persistent and often severe symptoms, though little is known about its etiology. The goal ...

Peripheral Vascular Exam Using a Continuous Wave Doppler

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Peripheral vascular disease (PVD) is a common condition affecting older adults and includes disease of the peripheral arteries and veins. While the history and physical exam offer clues to its diagnosis, Doppler ultrasound has become a routine part of the bedside vascular examination. The video titled &#34;The Peripheral Vascular Exam&#34; gave a detailed review of the physical examination of the peripheral arterial and venous systems. This video specifically reviews the bedside assessment of peripheral arterial disease (PAD) and chronic venous insufficiency using a handheld continuous wave Doppler.
The handheld Doppler (HHD) is a simple instrument that utilizes continuous transmission and reception of ultrasound (also referred to as continuous wave Doppler) to detect changes in blood velocity as it courses through a vessel. The Doppler probe contains a transmitting element that emits ultrasound and a receiving element that detects ultrasound waves (Figure 1). The emitted ultrasound is reflected off of moving blood and back to the probe at a frequency directly related to the velocity of blood flow. The reflected signal is detected and transduced to an audible sound with a frequency directly related to that of the received Doppler signal (thus, faster blood flow produces a higher frequency sound).
<img alt="Figure 1" src="/files/ftp_upload/10123/10123fig1.jpg" /> 
Figure 1. Generation of a Doppler signal. The handheld Doppler emits an ultrasound signal, which is then reflected back by moving blood, and finally received by the Doppler probe.
The HHD is easily used in the office or hospital setting to detect pulses, screen for PAD using the ankle brachial pressure index (ABPI), and localize venous insufficiency. This video reviews these procedures; however, it is not intended to be a comprehensive review of non-invasive vascular testing.

Fabrication of Compressed Hosiery and Measurement of its Pressure Characteristic Exerted on the Lower Limbs

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