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The traditional way of making a prosthetic socket is by draping a heated thermoplastic sheet over the positive mould, or by applying layers of woven materials together with acrylic resins over the positive mould. This process is extremely labour intensive, and it usually takes two to three days to make one socket. This paper presents the development of a prosthetics Computer‐Aided‐Manufacturing (CAM) system that utilises Rapid Prototyping (RP) technology. The system reduces the socket making time from days to less than 4 h. Clinical and biomechanical studies are conducted to evaluate the comfort and fit of the new socket during gait. Preliminary investigation of the new socket shows that its functional characteristics are very similar to that of a traditional socket

The number of people with special needs, including citizens and military personnel, has increased as a result of terrorist attacks and challenging conditions in Iraq and other countries. With almost 80% of the world’s amputees having below-the-knee amputations, Iraq has become a global leader in the population of amputees. Important components found in lower limb prostheses include the socket, pylon (shank), prosthetic foot and connections.

There are two types of prosthetic feet: articulated and nonarticulated. The solid ankle cushion heel foot is the nonarticulated foot that is most frequently used. The goal of this study is to use a composite filament to create a revolutionary prosthetic foot that will last longer, have better dorsiflexion and be more stable and comfortable for the user. The current study, in addition to pure polylactic acid (PLA) filament, 3D prints test items using a variety of composite filaments, such as PLA/wood, PLA/carbon fiber and PLA/marble, to accomplish this goal. The experimental step entails mechanical testing of the samples, which includes tensile testing and hardness evaluation, and material characterization by scanning electron microscopy-energy dispersive spectrometer analysis. The study also presents a novel design for the nonarticulated foot that was produced with SOLIDWORKS and put through ANSYS analysis. Three types of feet are produced using PLA, PLA/marble and carbon-covered PLA/marble materials. Furthermore, the manufactured prosthetic foot undergoes testing for dorsiflexion and fatigue.

The findings reveal that the newly designed prosthetic foot using carbon fiber-covered PLA/marble material surpasses the PLA and PLA/marble foot in terms of performance, cost-effectiveness and weight.

To the best of the author’s knowledge, this is the first study to use composite filaments not previously used, such as PLA/wood, PLA/carbon fiber and PLA/marble, to design and produce a new prosthetic foot with a longer lifespan, improved dorsiflexion, greater stability and enhanced comfort for the patient. Beside the experimental work, a numerical technique specifically the finite element method, is used to assess the mechanical behavior of the newly designed foot structure.

A contactless electromyography (EMG) electrodes design and development for prosthetics, particularly the Touch Hand 3, was the main objective of this paper. The correlation between EMG electrodes and patch antenna are described, with the problem relating to the dimensions of the covidien electrodes. The purpose of this paper is to improve the signal strength of the EMG electrodes and having them to not be in contact with the skin to cause irritation in the person.

A combination of the contact covidien electrodes and aluminium foil was used to develop electrodes that were in a similar configuration than a Yagi antenna. Different layers of patch elements were designed, developed and implemented.

Different layers of Yagi-patch electrodes are tested with different volunteers and compared with the average signal strengths obtained from the covidien electrodes. An improvement in signal strength with the Yagi-patch electrodes has been found.

The purpose of the work was to design, develop and test EMG electrodes that are cost-effective, reusable and able to improve the signal strengths that are recorded, for better functionality of prosthetic devices.

The integration of EMG and antennae theory to implement a Yagi-patch EMG electrode to improve on signal reception. The electrodes have the properties of being cheap, easy available, can eliminate direct contact and avoiding patches on the skin. Comparison of different layered electrodes with the contactless electrodes close to the skin. Comparison of the different electrodes on a silicone sleeve, which are commonly worn by amputees, placed between the skin and the prosthetic’s socket. Testing the Yagi-patch electrodes with an application with the prosthetic Touch Hand, to allow for the control of a system such as the Touch Hand.

There are over 40 million amputees globally with more than 185,000 Americans losing their limbs every year. For most of the world, prosthetic devices remain too expensive and uncomfortable. This paper aims to outline advancements made by a multidisciplinary research group, interested in advancing the restoration of human motion through accessible lower limb prostheses.

Customization, comfort and functionality are the most important metrics reported by prosthetists and patients. The work of this paper presents the design and manufacturing of a custom made, cost-effective and functional three-dimensional (3D) printed transtibial prosthesis monocoque design. The design of the prosthesis integrates 3D imaging, modelling and optimization techniques coupled with additive manufacturing.

The successful fabrication of a functional monocoque prosthesis through 3D printing indicates the workflow may be a solution to the worldwide accessibility crisis. The digital workflow developed in this work offers great potential for providing prosthetic devices to rural communities, which lack access to skilled prosthetic physicians. The authors found that using the workflow together with 3D printing, this study can create custom monocoque prostheses (Figure 16). These prostheses are comfortable, functional and properly aligned. In comparison with traditional prosthetic devices, the authors slowered the average cost, weight and time of production by 95%, 55% and 95%, respectively.

This novel digital design and manufacturing workflow has the potential to democratize and globally proliferate access to prosthetic devices, which restore the patient’s mobility, quality of life and health. LIMBER’s toolbox can reach places where proper prosthetic and orthotic care is not available. The digital workflow reduces the cost of making custom devices by an order of magnitude, enabling broader reach, faster access and improved comfort. This is particularly important for children who grow quickly and need new devices every few months or years, timely access is both physically and psychologically important.

In this manuscript, the authors show the application of digital design techniques for fabricating prosthetic devices. The proposed workflow implements several advantageous changes and, most importantly, digitally blends the three components of a transtibial prosthesis into a single, 3D printable monocoque device. The development of a novel unibody transtibial device that is properly aligned and adjusted digitally, greatly reduces the number of visits an amputee must make to a clinic to have a certified prosthetist adjust and modify their prosthesis. The authors believe this novel workflow has the potential to ease the worldwide accessibility crisis for prostheses.

As an application of the computer aided design and computer aided manufacturing (CAD/CAM) technology in prosthetics, computer aided socket design and computer aided socket manufacturing (CASD/CASM) is becoming an active field in the prosthetics research. In this paper, a CASD/CASM method for prosthetic socket fabrication is described in detail. This is different from other fabrication methods in its novel combination of the CAD/CAM technology with fused deposition modeling (FDM) technology. Prosthetic sockets for volunteer amputees have been designed and fabricated in a FDM machine. In order to test the fabrication result, a final product was used to perform a clinical trial and some results are reported. In addition, the deficiency of the long fabrication time is addressed and some feasible solutions are discussed.

The purpose of this paper is to examine the transformations of prosthetic practices in China, as well as the daily experiences and dilemmas arising from the everchanging practices since 1949. On the basis of materials, this paper explores an everyday perspective to review the history of technology.

Ethnography was collected with the application of participant observations, informal interviews and in-depth interviews during a 13-months study at a rehabilitation center in Chengdu, China. The literature on prosthetic manufacturing was also reviewed for this paper.

China's prosthetic technology seems to evolve from traditional to modern. However, this progressive narrative – innovation-based timeline (Edgerton, 2006, xi) – has been challenged by daily practices. Due to institutional pressures, prosthetists are in a dilemma of selectively using their knowledge to create one kind of device for all prosthesis users with a certain kind of disability, thereby regulating the physical and social experiences of prosthesis users. Besides, prosthesis users are accustomed to prostheses made with old techniques, and must correct themselves from old experiences to the daily practices recognized by the selected techniques.

This paper provides a cross-cultural case to reexamine Edgerton's criticism of the progressive and orderly innovation-centric technological narrative. More importantly, it reviews the history and practices of China's prosthetics from daily experiences rather than Edgerton's concentration on technology; therefore, it provides an everyday perspective for future research on technological transformations.

A prosthetic socket worn by an amputee must serve a wide variety of functions, from stationary support to the transfer of forces necessary to move. Because a subject's residual limb changes volume throughout the day, it is desirable that the socket adapt to accommodate volume changes to maintain fit and comfort. The purpose of this paper is to provide steps towards designing a transtibial nylon prothestic socket, fabricated by selective laser sintering (SLS), that automatically adapts to volumetric changes of a residual limb.

An adaptive socket design that has both rigid and compliant regions is proposed to be manufactured by SLS and actuated by inflation. To assess the feasibility of this approach, thin membrane test specimens of various thicknesses and materials were created to understand the relationship between inflation pressure and deflection for SLS manufactured plastics. Finite element analysis (FEA) was assessed as a predictive design tool and verified with the experimental inflation/deflection results.

The initial flat test specimens could only achieve deflection of 2.13 mm at 145 kPa (nylon 12) and 3.38 mm at 340 kPa (nylon 11). A curved specimen is created that met performance goals with 7.67 mm maximum deflection at 714 kPa. FEA for the flat specimens is an accurate predictor of performance, but the results of analyzing the curved specimens are an order of magnitude different from the experimental data.

The success of the physical curved specimens is encouraging for future research, but the FEA will need to be further developed before socket performance can be predicted with confidence.

A socket that does not fit the subject well will cause movement problems, rehabilitation difficulties, and potentially long‐term health issues. This research shows great potential for developing a socket that provides greater comfort and fit.

The purpose of this paper is to evaluate the performance of 3D printed materials for use as rapid tooling (RT) molds in low volume thermoforming processes such as in manufacturing custom prosthetics and orthotics.

3D printed specimens of different materials were produced using the Z‐Corp process. The parts were post processed using both standard and alternative methods. Material properties relevant to the 3D printed parts such as pneumatic permeability, flexural strength and wear rate were measured and compared to standard plaster compositions commonly used.

Three‐dimensional printing (3DP) can replicate the performance of the plaster materials traditionally used in prosthetic/orthotic applications by using modified post process techniques. The resulting 3D printed molds can still be modified and adjusted using traditional methods. The results show that 3D printed molds are feasible for thermoforming prosthetic and orthotic devices such as prosthetic sockets while providing new flexibility.

The proposed method for RT of a mold for prosthetic/orthotic manufacturing provides great flexibility in the manufacturing and fitting process while maintaining proven materials in the final device provided to patients. This flexibility increases the value of digital medical records and efforts to develop model‐based approaches to prosthetic/orthotic device design by providing a readily available process for recreating molds. Depending on the needs of the practitioners and patients, 3DP can be incorporated at a variety of points in the manufacturing process.

Fused filament fabrication (FFF) using tough poly lactic acid (PLA) was determined to be the most suited method to achieve low-cost prosthetic sockets. However, improvement in the material properties is desirable to strengthen these sockets. This study aims to evaluate annealing as a potential method to improve material properties by a heat treatment of the object after 3D printing.

Four different annealing methods and a control group were tested according to ISO standard 527–1 and ISO standard 527–2. The four annealing methods included: oven; sand; water; and glycerol annealing. Tests were performed on longitudinal and transversal 3D printed samples. Deformation was determined on 3D printed test rings.

Annealing using an oven, sand and water resulted in a significant increase in tensile strength in longitudinally 3D printed tensile test samples. However, the tensile strength was decreased in the transversally 3D printed tensile test samples. The tensile modulus had no significant increase in the longitudinally and transversally printed samples. Sand annealing resulted in the least deformation, with a shrinkage of 2.04% of inner diameter and an increase in height of 1.99% for the horizontally annealed test rings.

The annealing of prosthetic sockets is not recommended as a decrease in tensile strength in transversally printed tensile test samples was observed. More research is needed towards the strengthening of tough PLA in both print directions.

This paper fulfils the need for understanding the impact of annealing on 3D printed items intended for daily use, such as a prosthetic socket.

Medical devices are undergoing rapid changes because of the increasing affordability of advanced technologies like additive manufacturing (AM) and three-dimensional scanning. New avenues are available for providing solutions and comfort that were not previously conceivable. The purpose of this paper is to provide a comprehensive review of the research on developing prostheses using AM to understand the opportunities and challenges in the domain. Various studies on prosthesis development using AM are investigated to explore the scope of integration of AM in prostheses development.

A review of key publications from the past two decades was conducted. Integration of AM and prostheses development is reviewed from the technologies, materials and functionality point of view to identify challenges, opportunities and future scope.

AM in prostheses provides superior physical and cognitive ergonomics and reduced cost and delivery time. Patient-specific, lightweight solutions for complex designs improve comfort, functionality and clinical outcomes. Compared to existing procedures and methodologies, using AM technologies in prosthetics could benefit a large population.

This paper helps investigate the impact of AM and related technology in the field of prosthetics and can also be viewed as a collection of relevant medical research and findings.