Interface Pressure Measurement Research Articles

Design and Verification of an Automated Pressure Mapping System and Modulating Air Cells for Pressure Ulcer Prevention

This research focuses on developing an intelligent air mattress prototype based on commercially available alternating pressure air mattresses to prevent pressure ulcers. Force-sensitive resistors (FSRs) are installed under each air cell to measure interface pressure values occurring at different parts of the body. These collected values are then used to create pressure maps, indicating areas of high overpressure. The prototype incorporates a smart pneumatic control system divided into seven functional areas: head, back, waist, buttocks, thighs, calves, and heels. All operations are performed using LabVIEW software.

Double Optical Fiber Temperature Compensation Method for Measurement of Interface Pressure Between Simulated Cable and Accessory at High Temperatures

Reliable interface pressure between cables and accessories is closely associated with the safe operation of a power cable system. Using an external optical fiber Bragg grating temperature-compensating curvature sensor, a new method for online measurement of the interface pressure between a cable and an accessory at high temperatures is proposed. On the basis of the sensing principle of a fiber Bragg grating, a mathematical pure bending model, and a model of a thick-walled cylinder, a fiber Bragg grating temperature-compensating curvature sensor is fabricated using Dow Corning Sylgard-184 silicone rubber. The interface pressures of 10 kV cable accessories with different expansion rates at different temperatures are measured. The results of the measurements show that the temperature-compensated deviation of wavelength measurements made by the fiber grating curvature sensor ranges from -2.59% to 5.50%. The interface pressure between the cable and the accessory gradually increases with an increase in temperature from 30 to 60 °C. The results are consistent with the results of measurements made using a traditional piezoelectric sensor. This method is expected to evaluate the long-term reliability of the interface pressure of cable accessories in actual complex-temperature environments.

Validation of a Custom Interface Pressure Measurement System to Improve Fitting of Transtibial Prosthetic Check Sockets.

Achievement of fit between the residual limb and prosthetic socket during socket manufacture is a priority for clinicians and is essential for safety. Clinicians have recognised the potential benefits of having a sensor system that can provide objective socket-limb interface pressure measurements during socket fitting, but the cost of existing systems makes current technology prohibitive. This study will report on the characterisation, validation and preliminary clinical implementation of a low cost, portable, wireless sensor system designed for use during socket manufacture. Characterisation and benchtop testing demonstrated acceptable accuracy, behaviour at variable temperature, and dynamic response for use in prosthetic socket applications. Our sensor system was validated with simultaneous measurement by a commercial sensor system in the sockets of three transtibial prosthesis users during a fitting session in the clinic. There were no statistically significant differences between the sensor system and the commercial sensor for a variety of functional activities. The sensor system was found to be valid in this clinical context. Future work should explore how pressure data relates to ratings of fit and comfort, and how objective pressure data might be used to assist in clinical decision making.

Adjustable compression wraps: stretch, interface pressures and static stiffness indices.

Adjustable compression wraps (ACWs) may represent the future of compression for the treatment of the most severe stages of chronic venous diseases and lymphedema. We tested in five healthy subjects: Coolflex® from Sigvaris®; Juzo wrap 6000®, Readywrap® from Lohmann Rauscher®; Juxtafit® and Juxtalite® from Medi®, Compreflex® from Sigvaris®. The objective of this pilot study was to study the stretch, interface pressures, and Static Stiffness Index (SSI) of the six ACWs applied to the leg. The stretch was evaluated by stretching the ACWs to their maximum length. Interface pressure measurements were performed using a PicoPress® transducer and a probe placed at point B1. Interface pressures were measured in the supine resting position and in the standing position. We calculated the SSI. We started the measurements at 20 mmHg in the supine position and increased the pressures by 5 mmHg to 5 mmHg. Coolflex® (inelastic ACW) cannot exceed a maximum pressure of 30 mmHg at rest with a maximum SSI of approximately 30 mmHg. Juzo wrap 6000® (a 50% stretch) and Readywrap® (a 60% stretch) have a profile of stiffness very near one to the other. The optimal stiffness for Juzo is from 16 mmHg to of 30 mmHg for a resting pressure between 25 mmHg and 40 mmHg. For Readywrap, the optimal stiffness is from 17 mmHg to 30 mmHg with a maximum SSI of 35mmHg. The optimal application zone of this wrap at rest is 30 to 45 mmHg. Juxtafit®, Juxtalite® and Compreflex® (respectively 70%, 80%, 124% stretch) can be applied with pressures above 60 mmHg but with maximum SSI of 20 mmHg for Circaid® and>30 mmHg for Compreflex®. This pilot study allows us to propose a classification of wraps according to their stretch: inelastic ACW and short or long stretch ACW (50-60% and 70%, 80%, and 124% stretch). Their stretch and stiffness could help to better determine what could be expected of ACWs in clinical practice.

Test–retest reliability of muscular performance tests and compression garment interface pressure measurements: a comparison between consecutive and multiple day recovery

Test–retest reliability of muscular performance tests and compression garment interface pressure measurements: a comparison between consecutive and multiple day recovery

Thermo-mechanical and degradation properties of naturally derived biocomposites for prosthesis applications: Analysis of the interface pressure and stress distribution on the developed socket

Nowadays, the reduction of petroleum products has been aggressively studied due to their environmental concerns and for finding alternative synthetic materials for sustainable development. Thus, naturally derived biocomposites have great potential for creating a sustainable economy with reduced environmental pollution. The present study deals in two major parts; first, the fabrication of the knee prosthetic socket from different laminate biocomposites (FFF, KKK, and RRR) and examined their mechanical performance, thermal stability and degradation behaviour. The interface pressure between the developed socket and residual limb has been examined using the F-socket sensor. Second, the output data of experiential tests and measured interface pressure have been used for numerical analysis to examine the equivalent stress, deformation and safety factor of the sockets at different loading conditions (500 N, 700 N and 900 N). The results observed that FFF biocomposites have maximum compressive strength (121.0 6MPa), impact strength (36.86 kJ/m2), and shear strength (28.51 MPa) which is 8.15%, 49.53%, and 58.88% higher than RRR biocomposites and 2.74%, 34.62%, and 39.28% higher compared to KKK biocomposites, respectively. RRR biocomposites recorded higher hardness (68.42) and fatigue endurance stress (82.86 MPa) due to higher brittleness properties. The thermogravimetric analysis and degradation behaviour have been analyzed to examine thermal stability, degradation temperature, and degradation weight loss behaviour of biocomposites. Finally, the stress generation on the developed socket during the gait cycle is much lower than its calculated strength that did not affect the performance of the socket. Therefore, laminated biocomposites can be an alternative biomaterial to plastics and conventional materials due to their lighter weight, higher flexibility, and economical to provide greater comfort to the users for knee prosthesis applications.

Experimental Study on Measurement of Interfacial Pressure in Granular Materials

Abstract The properties of storage system structures were largely determined by the particle size and compressive modulus of the granular material inside, which is an important issue for silo structure design. The large compressibility and complex contact relationship of granular materials in the cell are needed for the reliable pressure measurement. A set of testing system and experiment method were designed to reveal the size effect of earth pressure cells in the loading and unloading process of granular materials. Different compressive moduli were adopted for the selection of the appropriate granular particle size. Four types of granular materials including fine sand, coarse sand, rapeseed, and wheat were used as raw materials. Three types of earth pressure cells were used in this study with different sizes, and a series of loading and unloading tests were conducted with liquid. The interaction between the cell and granular material and its main factors were discussed. The results show that the pressure exhibits a linear relationship with the strain in the loading and unloading process in liquid surroundings. Owing to the interaction between the cell and granular materials, the pressure increased linearly with the strain in the loading process as well as a nonlinear relationship were exhibited in the unloading process. In the unloading process, an exponential model was proposed to simulate the pressure and strain based on the significant hysteresis phenomenon observed during unloading process. The hysteresis ratio (R) index was adopted to evaluate the hysteresis. It was found that the material type of surroundings and particle size were believed to be the two major factors affecting the R value. To improve the accuracy of granular material interface pressure measurement, the earth pressure cell with a d/d0 ratio exceeding 11 was recommended. The results obtained in this study provide theoretical foundation for energy saving and safety granary structure design.

Method for Measuring Interface Pressure of High-Voltage Cables

In high-voltage cables, because of the close fit of their internal structures, interface pressure is generated between conductor and insulator, which affects the performance of the cable. Studies on the calculation and testing of the interfacial pressure of cable conductors are scarce because of the lack of a unified formula and the difficulty of direct measurement. As such, in this study, we devised two methods for calculating and measuring the interface pressure of cable conductors. In the first, we used two physical experimental methods. We used the friction between cable components to perform the calculation and create an experimental method for determining cable conductor interface pressure; on the basis of the equation of the pressure inside and outside a thick-walled cylinder using elasticity mechanics, we calculated the interface pressure on the basis of the measurement of the strain state of the inner and outer diameters of each layer of the cable under different assembly and stripping conditions. We verified the effectiveness of the methods through physical tests and simulations using a YJLW03 1 × 1200 high-voltage cable. Then, we used simulation software ANSYS and SolidWorks to calculate the interface pressure. With different simulation settings, we obtained results regarding interface pressure. Lastly, these simulated values were individually compared with two physical tests, and the error was calculated. Results obtained in the ANSYS environment showed that interface pressure values determined by the geometric interference normal stress, geometric interference pressure, contact interference normal stress, and contact interference pressure methods were 39.75, 36.84, 5.76, and 36.57 MPa, respectively. In SolidWorks software, we used the contact-stress and X-axis normal stress methods. Results were all 37.36 MPa. Then, simulation results and experimental results were compared, and error was calculated. The comparison showed that the X-axis orthogonal stress method was the most accurate. Errors between the X-axis orthogonal stress method and the two physical experiments were 1.5% and 0.48%. Through the above simulation and physical experiments, we determined the interface pressure between conductors and insulators in a high-voltage power cable. We obtained the cable interface pressure value through two kinds of physical experiments, and these two methods were clearly reliable. Simulation experiments showed that using SolidWorks software to simulate this problem obtained better results. Research results provide technical support and reference for the calculation and measurement of cable interface pressure and the optimization of cable performance.

Investigating the inaccuracies of indirect method of blood pressure measurement associated to the cuff constructing fabrics

Numerous cuffs have been manufactured using different materials in which textile fabric is the main constituent. There are no specific guidelines for the selection of the cuff fabric and its design. In this investigation, five different types of cuffs (made of woven and non-woven fabrics) were selected, and their pressure distribution was noted while mimicking the process of blood pressure measurement. It was achieved by measuring pressure at the interface of the selected cuffs and a bare metal cylinder. I-scan, an interface pressure measurement system was employed to record the interface pressure profiles under the cuffs against 140 mmHg to 40 mmHg pressure inside the cuffs. The data obtained from the pressure sensing system was processed in MATLAB to examine pressure distribution at 96 points in detail. The results show that the cuffs registered non-uniform pressure distribution at the interface which is also non-identical among the selected cuffs. The pressure at the interface is found to be lower than the pressure inside the cuff, which shows that pressure attenuates as transfers to the surface of the object underneath it. The range of the pressure difference varies from 10 mmHg to 15 mmHg. This study indicates that the pressure distribution under a cuff depends on the constructing fabric and its properties. It is concluded that there is a need to select appropriate fabric with optimized properties for desired pressure distribution which may lead to accurate estimation of blood pressure.

Follow-Up Study of Subdermal Low-Echoic Lesions in the Ischial Region in Wheelchair Users With Spinal Cord Injuries.

Objective:To follow up patients with spinal cord injuries with subdermal low-echoic lesions in the ischial region for abnormalities after 1 year.DesignA retrospective cohort study.SettingA Japanese rehabilitation center.ParticipantsWe included patients with chronic spinal cord injuries and subdermal low-echoic lesions who underwent routine inspection and palpation examinations (n = 7).InterventionsEducation on pressure injury and instruction on pressure relief and seating was provided and the patients were followed up for abnormalities after 1 year. Self-reports were obtained on wheelchair sitting time, and interface pressure was recorded while the patients were seated on the wheelchair. Interface pressure measurements at the bilateral ischial regions were recorded with a force-sensitive application pressure mapping system.Outcome MeasuresThe primary outcome was the presence of subdermal low-echoic lesions in the bilateral ischial regions on ultrasonography at the 1-year follow-up examination. Secondary outcomes included wheelchair sitting time and interface pressure in the bilateral ischial regions.ResultsOf the 10 areas that showed subdermal low-echoic lesions on ultrasonography, nine had improved after 1 year. One area that did not improve was an open wound. At the follow-up examination, the pressure duration was reduced in all patients, and the interface pressure could be reduced in 5/7 patients.ConclusionsThis is the first study to follow up with patients having spinal cord injuries and subdermal low-echoic lesions in the ischial region using ultrasonography. The low-echoic lesions improved within 1 year by reducing the pressure duration and interface pressure. Pressure injury prevention in patients with spinal cord injuries relies on the early detection of skin abnormalities, and education and instruction to change self-management behaviors are recommended.

Bandages Static Stiffness Index Is Not Influenced by Calf Mechanical Properties but Only by Geometrical Changes

Interface pressure applied by compression bandages is the therapeutic action of the treatment of some venous or lymphatic pathologies. The so-called Static Stiffness Index, which quantifies the pressure increase from supine to standing position, is usually used to differentiate compression bandages. It was hypothesized that this pressure increase was the consequence of a change in leg geometry (blood and muscle falling down) and a change in calf soft tissue mechanical properties (muscles contraction). Calf soft tissue global stiffness of both legs of 25 patients was characterized in a sitting and standing position. This characterization was combined with interface pressure measurements applied by six different bandages. Though soft tissue mechanical properties significantly increased from sitting to standing position, no correlation was observed with the corresponding pressure increase. Thus, pressure increase is mainly attributed to a change in leg geometry.

Predicting the cut‐off point for interface pressure in pressure injury according to the standard hospital mattress and polyurethane foam mattress as support surfaces

This study aimed to investigate the interface pressure (IP) of patients using a standard hospital mattress and polyurethane foam mattress as support surfaces and present cut‐off points for IP in patients who exhibited skin changes. A total of 189 inpatients enrolled from six general wards and three intensive care units at a Korean University Hospital. Skin changes were classified, and peak IP at the sacral and occipital regions was measured using a pressure scanner. Differences in IPs according to mattress type were analysed using independent t‐tests. The receiver operating characteristic curve was constructed to determine the cut‐off point, and the area under the curve with a 95% confidence interval was obtained using the Stata 15.1.program. The IP for a standard hospital mattress was significantly higher than that of a polyurethane foam mattress. The cut‐off points for IP at the sacral region were 52.90 and 30.15 mm Hg for a standard hospital mattress and polyurethane foam mattress, respectively. The cut‐off point for IP at the occipital region was 36.40 mm Hg for a polyurethane foam mattress. Using IP measurements to prevent pressure injuries is important and employ individualised interventions based on the cut‐off points for different support surfaces.

Predictive Value of the Interface Pressure and Frequency of Pressure Ulcer in Elderly Patients in the İnternal Medicine Intensive Care Units

Aim: Pressure ulcers develop frequently in immobile elderly. Pressure is extrinsic factor and it plays a major role in ulcer development. Nurses use a pressure ulcer risk assessment tools and risk assessment effectives as a means to ulcers preventing. To determine frequency and predictive value of interface pressure in pressure ulcer development in elderly patients hospitalized in internal medicine intensive care units. Materials and Methods: The study involved 140 patients admitted to internal intensive care clinics between May 2018 and August 2018 without pressure ulcers and who stayed in the ICU for more than 72 hours. Participants were scored using the Braden scale and were examined for the risk level of pressure ulcers. The inclusion criteria were age over 65 years and having a high risk of developing pressing ulcers. Patients were evaluated by “Questionnaire Form,“ Braden Risk Assessment Scale” and “ Palm Q-Portable Interface Pressure Sensor” every two days during their stay in the clinic. Results: Pressure ulcer developed in 22.1% of the patients but it didn’t develop in any of the oral feeding patients. The mean time for ulcer to develop was 6.90 (standard deviation 2.9) days. In patients with pressure ulcers, while the mean interface pressure value was 47.75 (standard deviation 6.79) mmHg at the beginning of the final evaluation position, 51.25 (standard deviation 6.71) mmHg at the end of the position. Conclusion: In all interface pressure measurements of patients who developed pressure ulcer, the interface pressure values increased at the end of the position compared to the beginning of the position.

An Exterior Optical Fibre Sensing Technology Used for Interface Pressure Measurement Between Cable and Accessory

Interface pressure between cable and accessory is the key to ensure the long-term reliable operation of cable accessories. The traditional measurement method of interface pressure is off-line measurement through a built-in piezoelectric sensor. However, this method is difficult to operate and damages the interface structure. In addition, the offline measurement cannot reflect the real-time dynamic change of interface pressure during the operation of cable accessories. Therefore, this paper proposes a new method for the on-line measurement of interface pressure between cable and accessory by means of an exterior optical fibre curvature sensor, whose design mechanism is based on the pure bending theory of optical fibre. Then the relationship model involving the exterior curvature of the cable accessory, the radial displacement and the inner interface pressure is established. Finally, interface pressures of the 8.7/10 kV cable accessory under different expansion ratios are measured by the calibrated optical fibre curvature sensor. The measurement results show that the optical fibre curvature sensor measures the exterior curvature of the accessory accurately; the average sensitivity reaches 7.679 nm/mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> , and the measurable curvature ranges from 0.03 to 0.05 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> . The conversion results of interface pressure are basically consistent with the results measured directly by a traditional piezoelectric sensor or simulated mechanically by finite element software. Therefore, the exterior optical fibre sensing technology proposed in this paper is expected to be used for the on-line measurement of the interface pressure between cable and accessory.

A Comparative Study of 2-Hour Interface Pressure in Different Angles of Laterally Inclined, Supine, and Fowler's Position.

Insufficient research exists for position change intervals to eradicate pressure ulcers. We tried to provide evidence for the position change interval by comparing peak pressure, risk area ratio, and the time to reach 30 mmHg and 60 mmHg, and presented this in detail, according to the angle in the three positions. The study conducted RCTs on a total of 64 healthy adults. For two hours, interface pressure measurements were compared with 30° and 90° tilting at the inclined, 0° and 45° head-of-bed (HOB) elevation at the supine, and 30° and 45° HOB elevation at the Fowler’s position. The peak pressure on 30° tilting remained less than 60 mmHg for 2 h, unlike 90° tilting. To reach 60 mmHg took 78.18 min at 30° tilting, within 30 min at the 30° supine, 30° and 45° at the Fowler’s position, and 39.55 min at 0° supine. The pressure difference according to the angles was only significant at 30° and 90° tilting, with no difference in the other groups. To prevent pressure ulcers, position changes are required every 2 h in the 30° tilting position, every 1.5 to 2 h at 0° supine, and at least every 1.5 h for all the other positions.

Effect of interface pressure and skin surface temperature on pressure injury incidence: a turning schedule pilot study.

This study aimed to evaluate the interface pressure and skin surface temperature in relation to the incidence of pressure injury (PI) using three different turning schedules. This was a pilot study with a three-armed randomised clinical trial design. Participants at risk of PI and treated in the high dependency care unit in a regional hospital in Makassar, Indonesia participated in this study. Patients were repositioned at three different turning schedules (two-, three- and four-hourly intervals). Interface pressure measurement and skin surface temperature were measured between 14:00 and 18:00 every three days. The incidence of PI was assessed during the two-week observation period. A total of 44 participants took part in the study. A one-way ANOVA test revealed no difference in interface pressure among the three different turning schedule groups within two weeks of observations: day zero, p=0.56; day four, p=0.95; day seven, p=0.56; day 10, p=0.63; and day 14, p=0.92. Although the average periumbilical temperature and skin surface temperature were not significant (p>0.05), comparison between these observation sites was significant on all observation days (p<0.05). Regarding the incidence of PI, the proportional hazard test for the development of PI in the three groups was considered not different (hazard ratio: 1.46, 95% confidence interval: 0.43-4.87, p=0.54). No difference in interface pressure and incidence of PI on the three turning schedules was observed; however, there was a potential increase in skin surface temperature in comparison with periumbilical temperature for all three turning schedules.

Design and fabrication of anisotropic textile brace for exerting corrective forces on spinal curvature

This study focuses on the fabrication of an anisotropic textile brace that exerts corrective forces based on the three-point pressure system to treat scoliosis, which is a medical condition that involves deformity of the spine. The design and material properties of the proposed anisotropic textile brace are discussed in detail here. A case series study with 5 scoliosis patients has been conducted to investigate the immediate in-brace effect and biomechanics of the proposed brace. Radiographic examination, three-dimensional scanning of the body and interface pressure measurements have been used to evaluate the immediate effect of the proposed brace on reducing the spinal curvature and asymmetry of the body contours and its biomechanics. The results show that the proposed brace on average reduces the spinal curvature by 11.7° and also increases the symmetry of the posterior trunk by 14.1% to 43.2%. The interface pressure at the corrective pad ranges from 6.0 to 24.4 kPa. The measured interface pressure shows that a sufficient amount of pressure has been exerted and a three-point pressure distribution is realized to reduce the spinal curvature. The obtained results indicate the effectiveness of this new approach which uses elastic textile material and a hinged artificial backbone to correct spinal deformity.

The accuracy and precision of interface pressure measuring devices: A systematic review.

Interface pressure measuring devices are used to assess the pressures exerted by compression. Their performance, however, has not been considered as a contributing factor to reported inconsistences in the application of compression. A systematic review was undertaken to investigate the performance of commercially available devices used to measure interface pressure. Six databases were searched identifying 17 devices, grouped into five sensor categories. A range of methodologies assessed the devices' accuracy and precision, including method of pressure application, device calibration and type of surface used. No sensor category outperformed the others, however some individual sensors showed higher accuracy and/or precision compared to others. Two major factors influenced the performance of a number of sensors: the amount of applied pressure and the calibration method used. Inconsistences in the application of compression may reflect, in part, issues related to accuracy and precision of the devices used to assess compression.

Comparison between the portable pressure measuring device and PicoPress® for garment pressure measurement on hypertrophic burn scar during compression therapy

PurposeThe current standard treatment for hypertrophic scars following burn injury is pressure garment therapy. The experimenters developed the novel portable pressure measuring device using silicon piezoresistive sensors. As PicoPress® is the most accurate (i.e., lowest variation and error) manometric sensor for pressure measurement, we sought to compare and examine the accuracy of the novel device regarding in vitro pressure measurements at the hypertrophic scar–pressure garment interface. MethodsThe novel device was designed to operate in non-corrosive media, such as air. The device can use up to six pressure sensing points and was developed to adjust the number of pressure sensors according to the size of the scar. Pressure measurements were acquired through a readout circuit consisting of an analog-to-digital converter, a microprocessor, and a Bluetooth transmission module for wireless data transmission to an external device. All signals were converted into mean pressure expressed in millimeters of mercury (mmHg). The mean pressure values measured by the sensors were compared to those obtained from PicoPress®. 55 garment pressures recordings were obtained from the sensors over this study conducted in 2018–February 2020. We then analyzed the test–retest reliability using the intraclass correlation coefficients (ICC). PicoPress® was also employed in the same pressure garments for obtaining similar measurements. A two way random effects model ICC with 95% confidence intervals was used to compare the mean pressure values obtained from the silicon piezoresistive sensors to the PicoPress® measurements. ResultsThe test–retest reliability of the pressure sensors was close to the acceptable level for clinical use regarding stationary interface pressure measurement (ICC = 0.99, 95% CI 0.990−0.997). The mean pressure obtained from the silicon piezoresistive pressure sensors showed an accordance with the measurements from PicoPress® (ICC = 0.97, 95% CI 0.947−0.985). ConclusionThe novel device may present a viable alternative to PicoPress® for garment pressure measurements. In addition, the novel device improves adaptability to the hypertrophic scar shape and size. Complementary characteristics such as wireless transmission to an external device may allow burn patients to continuously wear the device for real-time measurements during pressure garment therapy, thus improving existing devices including PicoPress®.

Review on the Interface Pressure Measurement for Below Knee Prosthetic Socket

The prosthesis consists of several essential parts such as socket, shank, ankle, and foot. A socket is an important part of prosthetic limbs; it is an interface between the residual limb and prosthetic parts. Biomechanics of socket-residual limb interface, particularly the effect of pressure and force distribution, has on the amputee regarding comfort and function. The most demanding process is designing and fitting of the socket. This is because each patient’s residual limb is unique and complex. It is very significant to take into account the interface pressure of an amputee patient. The prosthetic socket dispenses the entire weight of the amputee’s torso while in the walking cycle. This is why it is vital to measure the quantity of these interface stresses to measure the amount of damage the socket imposes on the residual limb tissues. Different types of methods have been utilized to identify the locations of extreme stresses that might cause skin breakdown. A comparison of stress distributed in a number of socket designs was made to assess interface cushioning and suspension systems, among others.